United States Environmental Monitoring Systems
Environmental Protection Laboratory
Agency Research Triangle Park NC 27711
Research and Development EPA-600/4-77-027a July 1984
X-/EPA Quality Assurance
Handbook for
Air Pollution
Measurement
Systems:
Volume II. Ambient
Air Specific Methods
Sections 2.1, 2.2,
2.6, and 2.9
-------
April 1984
Volume II
Table of Contents
Section Pages Date
Purpose and Overview of the Quality
Assurance Handbook 5 12-30-81
2.0 General Aspects of Quality Assurance for
Ambient Air Monitoring Systems
2.0.1 Sampling Network Design and Site
Selection 23 7-01-79
2.0.2 Sampling Considerations 9 7-01-79
2.0.3 Data Handling and Reporting 13 7-01-79
2.0.4 Reference and Equivalent Methods 6 7-01-79
2.0.5 Recommended Quality Assurance
Program for Ambient Air Measurements 5 7-01-79
2.0.6 Chain-of-Custody Procedures for
Ambient Air Samples 11 7-01-79
2.0.7 Traceability Protocol for Establishing
True Concentrations of Gases 6 6-15-78
Used for Calibration and Audits of Air 6 3-13-79
Pollution Analyzers (Protocol No. 2) 12
2.0.8 Calculations to Assess Monitoring
Data for Precision and Accuracy for
SLAMS and PSD Automated Analyzers
and Manual Methods 18 7-01-79
2.0.9 Specific Guidance for a Quality
Control Program for SLAMS and PSD
Automated Analyzers and Manual
Methods 27 7-11-79
2.0.10 USEPA National Performance Audit
Program 3 7-01-79
2.0.11 System Audit Criteria and Procedures
for Ambient Air Monitoring Programs 86 7-01-80
2.0.12 Audit Procedures for Use by State
and Local Air Monitoring Agencies 101 7-01-80
2.1 Reference Method for the
Determination of Sulfur Dioxide in
the Atmosphere (Pararosaniline Method)
2.1.1 Procurement of Equipment and
Supplies 3 1-10-83
2.1.2 Calibration of Equipment 14 1-10-83
2.1.3 Preparation of Reagents 4 1-10-83
2.1.4 Sampling Procedure 10 1-10-83
2.1.5 Analysis of Samples 7 1-10-83
2.1.6 Data Reduction, Validation and
Reporting 4 1-10-83
2.1.7 Maintenance 1 1-10-83
2.1.8 Auditing Procedure 4 1-10-83
2.1.9 Assessment of Monitoring Data for
Precision and Accuracy 2 1-.10-83
2.1.10 Recommended Standards for
Establishing Traceability 1 1-10-83
2.1.11 Reference Method 11 1-10-83
2.1.12 References 1 1-10-83
2.1.13 Data Forms 16 1-10-83
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April 1984
Table of Contents (continued)
Section Pages Date
2.2 Reference Method for the
Determination of Suspended
Particulates in the Atmosphere
(High-Volume Method)
2.2.1 Procurement of Equipment and
Supplies 2 1-10-83
2.2.2 Calibration of Equipment 13 1-10-83
2.2.3 Filter Selection and
Preparation 4 1-10-83
2.2.4 Sampling Procedure 8 1-10-83
2.2.5 Analysis of Samples 1 1-10-83
2.2.6 Calculations and Data Reporting 2 1-10-83
2.2.7 Maintenance 2 1-10-83
2.2.8 Auditing Procedure 4 1-10-83
2.2.9 Assessment of Monitoring Data for
Precision and Accuracy 1 1-10-83
2.2.10 Recommended Standards for
Establishing Traceability 1 1-10-83
2.2.11 Reference Method 10 1-10-83
2.2.12 References 1 1-10-83
2.2.13 Data Forms 10 1-10-83
2.3 Reference Method for the
Determination of Nitrogen Dioxide in
the Atmosphere (Chemiluminescence)
2.3.1 Procurement of Apparatus and
Supplies 8 7-01-79
2.3.2 Calibration of Equipment 27 7-01-79
2.3.3 Operation and Procedure 10 7-01-79
2.3.4 Data Reduction, Validation and
Reporting 5 7-01-79
2.3.5 Maintenance 2 7-01-79
2.3.6 Auditing Procedure 12 7-01-79
2.3.7 Assessment of Monitoring Data for
Precision and Accuracy 1 7-01-79
2.3.8 Recommended Standards for
Establishing Traceability 1 7-01-79
2.3.9 Reference Method 9 7-01 -79
2.3.10 References 1 7-01-79
2.3.11 Data Forms 17 7-01-79
2.4 Eqivalent Method for the
Determination of Nitrogen Dioxide in
the Atmosphere (Sodium Arsenite)
2.4.1 Procurement of Equipment and
Supplies 6 12-30-81
2.4.2 Calibration of Equipment 13 12-30-81
2.4.3 Preparation of Reagents 3 12-30-81
2.4.4 Sampling Procedure 10 12-30-81
2.4.5 Analysis of Samples 13 12-30-81
2.4.6 Data Reduction, Validation and
Reporting 3 12-30-81
2.4.7 Maintenance 2 12-30-81
2.4.8 Auditing Procedure 11 12-30-81
2.4.9 Assessment of Monitoring Data for
Precision and Accuracy 1 12-30-81
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April 1984
Table of Contents (continued)
Section Pages Date
2.4.10 Recommended Standards for
Establishing Traceability 2 12-30-81
2.4.11 Equivalent Methods 37 12-30-81
2.412 References 2 12-30-81
2.413 Data Forms 9 12-30-81
2.5 Equivalent Method for the
Determination of Sulfur Dioxide in
the Atmosphere (Flame Photometric
Detector)
2.5.1 Procurement of Apparatus and
Supplies 9 12-30-81
2.5.2 Calibration of Equipment 19 12-30-81
25.3 Operation and Procedure 10 12-30-81
2.5.4 Data Reduction, Validation and
Reporting 5 12-30-81
2.5.5 Maintenance 2 12-30-81
2.5.6 Auditing Procedure 11 12-30-81
2.5.7 Assessment of Monitoring Data for
Precision and Accuracy 1 12-30-81
2.5.8 Recommended Standards for
Establishing Traceability 2 12-30-81
2.59 Equivalent Method 1 12-30-81
2.5.10 References 1 12-30-81
2.5.11 Data Forms 15 12-30-81
2.6 Reference Method for the
Determination of Carbon Monoxide in
the Atmosphere (Non-Dispersive Infrared)
Spectrometry
2.6.1 Procurement of Equipment and
Supplies 4 1-10-83
2.6.2 Calibration of Equipment 6 1-10-83
2.6.3 Operation and Procedure 6 1-10-83
2.6.4 Data Reduction, Validation and
Reporting 3 1-10-83
2.6.5 Maintenance 2 1-10-83
2.6.6 Auditing Procedure 4 1-10-83
2.6.7 Assessment of Monitoring Data for
Precision and Accuracy 1 1-10-83
2.6.8 Recommended Standards for
Establishing Traceability 1 1-10-83
2.6.9 Reference Method 3 1-10-83
2.6.10 References 1 1-10-83
2.1.11 Data Forms 12 1-10-83
2.7 Reference Method for the
Determination of Ozone in the
Atmosphere (Chemiluminescence)
2.7.1 Procurement of Equipment and
Supplies 10 12-30-81
2.7.2 Calibration of Equipment 21 12-30-81
2.7.3 Operation and Procedure 10 12-30-81
2.7.4 Data Reduction, Validation and
Reporting 5 12-30-81
2.7.5 Maintenance 2 12-30-81
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April 1984
Table of Contents (continued)
Section Pages Date
2.7.6 Auditing Procedure 8 12-30-81
2.7.7 Assessment of Monitoring Data for
Precision and Accuracy 1 12-30-81
2.7.8 Recommended Standards for
Establishing Traceability 1 12-30-81
2.7.9 • Calibration of Ozone
Reference Methods 13 12-30-81
2.7.10 References 1 12-30-81
2.7.11 Data Forms 13 12-30-81
2.8 Reference Method for the
Determination of Lead in Suspended
Particulate Matter Collected from
Ambient Air (Atomic Absorption
Spectrometry)
2.8.1 Procurement of Equipment and
Supplies 4 12-30-81
2.8.2 Calibration of Equipment 4 12-30-81
2.8.3 Filter Selection and Procedure 1 12-30-81
2.8.4 Sampling Procedure 1 12-30-81
2.8.5 Analysis of Samples 14 12-30-81
2.86 Calculations and Data Reporting 12 12-30-81
2.8.7 Maintenance 3 12-30-81
2.8.8 Auditing Procedure 12 12-30-81
2.8.9 Assessment of Monitoring Data for
Precision and Accuracy 1 12-30-81
2.8.10 Recommended Standards for
Establishing Traceability 1 12-30-81
2.8.11 Reference Method 6 12-30-81
2.8.12 References 2 12-30-81
2.8.13 Data Forms 6 12-30-81
2.9 Reference Method for the
Determination of Sulfur Dioxide in
the Atmosphere (Fluorescence)
2.9.1 Procurement of Apparatus and
Supplies 5 9-10-82
2.9.2 Calibration of Equipment 10 9-10-82
2.9.3 Operation and Procedure 7 9-10-82
2.9.4 Data Reduction, Validation and
Reporting 1 9-10-82
2.9.5 Maintenance 2 9-10-82
2.9.6 Auditing Procedure 1 9-10-82
2.9.7 Assessment of Monitoring Data for
Precision and Accuracy 1 9-10-82
2.9.8 Recommended Standards for
Establishing Traceability 1 9-10-82
2.9.9 Equivalent Method 1 9-10-82
2.9.10 References 1 9-10-82
2.9.11 Data Forms 4 9-10-82
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Jan. 1983
Section 2.1.0
United States
Environmental Protection
Agency
Environmental Monitoring Systems
Laboratory
Research Triangle Park NC 27711
Research and Development
EPA-600/4-77-027a
oEPA
Test Method
Section 2.1
Reference Method for the
Determination of Sulfur
Dioxide in the Atmosphere
(Pararosaniline Method)
Outline
Section
Summary
Method Highlights
Method Description
1. Procurement of Equipment
and Supplies
2. Calibration of Equipment
3. Preparation of Reagents
4. Sampling Procedure
5. Analysis of Samples
6. Data Reduction, Validation,
and Reporting
7. Maintenance
8. Auditing Procedure
9. Assessment of Monitoring Data
for Precision and Accuracy
10. Recommended Standards for
Establishing Traceability
11. Reference Method
12. References
13. Data Forms
Documentation
2.1
2.1
2.1.1
2.1.2
2.1.3
2.1.4
2.1.5
2.1.6
2.1.7
2.1.8
2.1.9
2.1.10
2.1.11
2.1.12
2.1.13
Number of
Pages
14
4
10
7
4
1
4
2
11
1
16
Summary
When sulfur dioxide (SO?) is
absorbed from ambient air into a
solution of potassium
tetrachloromercurate (TCM), a
monochlorosulfonatomercurate
complex (MSM) is formed that resists
oxidation by oxygen in the air. This
complex can be considered stable at
15°±10°C only during sampling. The
sample then must be stored at 5°C
until analysis to prevent any further
degradation. (Thermally controlled
sampling equipment is commercially
available.) The MSM is reacted with
pararosaniline (PRA) and formalde-
hyde to form an intensely colored dye
(pararosaniline methyl sulfonic acid),
and the absorbance of the dye is
measured spectrophotometrically.
-------
Section 2.1.0
Jan. 1983
This method can be used to
determine S02 levels in ambient air
during sampling periods ranging from
30 mm to 24 h. The detection limit for
the method is 25 /jg S02/m3 (0.01
ppm) in an air sample of 30 standard
liters (short-term sampling) and 13^g
SOa/m3 (0 005 ppm) in an air sample
of 288 standard liters (long-term
sampling)
Based on extensive review and on
experience gained in audits and in
collaborative tests,1'2 the PRA method
description and the recommended
limits for quality checks and audits
presented herein sometimes differ
from and supersede those in the
guideline document.3 On the other
hand, that document contains
functional and error analyses that are
not included in this Handbook
A copy of the Reference Method is
in Section 2.1.11 Blank data forms in
Section 2.1.1 3 are for the
convenience of the Handbook user
Recommended equivalent methods
are published in the Federal Register
and quarterly in the Quality
Assurance Newsletter issued by the
U.S. Environmental Protection
Agency, Environmental Monitoring
and Support Laboratory, Cincinnati,
Ohio 45268. See Section 2.0.4 of this
volume of the Handbook for a
discussion of equivalency concepts.
Method Highlights
In this quality assurance document
for the SOa Reference Method, the
procedures are designed to serve as
guidelines for the development of
agency quality assurance programs.
Because recordkeeping is a critical
part of quality assurance activities,
several data forms are included to aid
in the documentation of necessary
data. The blank data forms (Section
2.1.13) may be used as they are, or
they may serve as guidelines for
preparing forms more appropriate to
the individual agency; partially filled-
in forms are interspersed throughout
the text of the method description to
illustrate their uses. Activity matrices
at the end of pertinent sections can
be used for quick review of the
material covered in the text sections
Following is a brief summary of the
material covered in this S02 method
description
1. Procurement of Equipment
Section 2.1.1 describes the selection
of equipment and the performance of
procurement and calibration checks of
the equipment; all are prerequisites
for a quality assurance program.
Section 2.1.1 conveniently identifies
the sections/subsections of this part
of the Handbook that pertain to
specific equipment and supplies, and
Figure 1.1 provides an example of a
permanent procurement record.
2. Calibration of Equipment Section
2 1 2 provides detailed calibration
procedures for flow measurement
equipment, analytical balance, timer,
and elapsed-time meter This section
can be removed, along with the
corresponding sections of the other
methods of this volume, to serve as a
calibration handbook. Table 2.4 at
the end of Section 2.1.2 provides a
summary of the acceptance limits for
calibration This section is unique in
that it contains detailed calibration
procedures for almost all flow
measurement equipment used in
ambient air sampling and analysis.
3. Preparation of Reagents Section
2.1 3 describes the preparation and
handling of reagents Reagents must
be carefully prepared, stored, and
maintained fresh (i.e., within the
acceptable limits of shelf life). Table
3 1 at the end of this section
summarizes the important activities
for their preparation and storage.
4. Sampling Procedure Section 2.1.4
provides a detailed description of the
selection and assembly of the
apparatus and the checkout of the
performance. The operator must
perform the initial and final flow
measurements and should perform
the operational checks listed in
Subsection 4.3 1 before collection of
the sample and the postsampling
checks listed in Subsection 4.3.2 after
the sample collection The data record
form (Figure 4.10 of Section 2.1.4)
summarizes the information required
to ensure the availability of good
quality data and background
information Because the SOz-TCM
complex is thermally unstable, the
SOz concentration depends greatly on
the temperature history of the TCM
absorbing solution. The user of this
method should also refer to Reference
8 in Section 2 1.12.
5. Analysis of Samples Section 2.1.5
contains a step-by-step procedure for
colonmetric analysis, acceptance
limits for the calibration curve,
traceability check, and laboratory data
log. The appropriate limits are given in
Table 5.2 at the end of Section 2.1.5.
6. Data Reduction, Validation, and
Reporting Section 2.1.6 describes
those activities pertaining to data
calculations and reporting. An
important part of a quality assurance
program is the final data review, the
data edit or validation, and the use of
standardized reporting procedures.
Independent checks of the data and
calculations are recommended to
ensure that the reported data are both
accurate and precise.
7. Maintenance Section 2.1.7
recommends periodic maintenance
schedules to ensure that the
equipment is capable of performing in
accordance with specifications.
8. Assessment of Data for Accuracy
and Precision Section 2.1.8 and 2.1.9
describe the assessment of the data
for accuracy and precision,
respectively. Independent audit
activities provide accuracy checks of
the flow rate measurements, the
analysis process with the use of
reference samples (EPA audit
samples), and the data processing
The precision check is performed by
using a collocated sampler as a
reference. The expected agreement
between two collocated sampling
trains is given in Table 9.1 and Figure
9 1 of Section 2.1.9.
9. Reference Information Section
2.1.10 discusses the traceability of
measurements to established
standards of higher accuracy, a
necessary prerequisite for obtaining
accurate data.
Sections 2.1.11 and 2.1.12 contain
the Reference Method and pertinent
references.
Section 2.1.13 contains blank data
forms for the convenience of the user.
-------
Jan. 1983 1 Section 2.1.1
Method Description
1.0 Procurement of Equipment and Supplies
Specifications for the sampling
equipment and for the analytical and
the support supplies for monitoring
sulfur dioxide (802) in ambient air are
described in Section 2.1.11. The list
below references the
sections/subsections of this
Handbook to help the user find
specific information needed for
procuring the equipment and supplies.
Item
Calibration Information
Wet test meter
Soap bubble meter
Mass flow meter
Rotameter
Flow-control devices
Analytical balance
E lapsed-time meter
Timer
Preparation of Reagents
Sampling Procedure
Absorber
A 24-h bubbler train
Temperature-controlled
shelter
Critical orifice
Vacuum pump
Moisture trap
Timer
Membrane paniculate filter
Analysis of Samples
Spectrophotometer
Maintenance
A 24-h bubbler train
Short-term sampling train
Section
2.1.2
2.1.2
2.1.2
2.1.2
2.1.2
2.1.2
2.1.2
2.1.2
2.1.3
2.1.4
2.1.4
2.1.4
2.1.4
2.1.4
2.1.4
2.1.4
2.1.4
2.1.5
2.1.7
2.1.7
Subsection
2.1.1
2.1.2
2.1.3
2.1.4
2.2
2.3
2.4
2.5
3.1-3.14
4.2.1-4.2.3. 4.2.5-4.2.7
4.2.6
4.2.6
4.2.7
4.3. 1. 4.3.2
4.3.2
4.3.1. 4.3.2
4.3.2
5.2. 5.3
7.1
7.2
The quality assurance functions are
summarized in Table 1.1. Upon receipt
of the sampling equipment, apparatus,
and supplies, the procurement checks
described in Table 1.1 should be
performed. All pertinent procurement,
disposition, and check information
should be recorded in a log such as
the one shown in Figure 1.1. This log
will serve as a permanent record for
future procurement needs, provide
continuity among users of equipment
and supplies, and provide a basis for
fiscal projections.
-------
Section 2.1.1
Jan. 1983
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Jan. 1983
Section 2.1.1
Table 1.1 Activity Matrix for Procurement of Equipment and Supplies
Equipment
Absorber
Vacuum pump
Acceptance limits
Reference Method,
Sec 2.1.11
Capable of maintaining an
air pressure differential
X). 7 atmosphere at
desired flow rate
Frequency and method
of measurement
Upon receipt, check
performance.
Upon receipt, check
performance.
Action if
requirements
are not met
Return to supplier.
Return to supplier.
Air flow control device
Spectrophotometer
Flow measurement devices
fwet-test meter, soap-bubble
meter, mass-flow meter, rota-
meter, flow-control devices,
analytical balance, elapsed-
time meter, timers)
Capable of controlling air
flow within 5% over the
length of the sampling
period
Suitable for measuring
absorbance at 548 ±5 nm
with an effective spectral
band width <15 nm
For acceptance limits rela-
tive to calibration checks,
see Table 2.4
Check upon receipt;
Sec. 2.2.
Verify wavelength calibra-
tion upon receipt and after
every 160 h of use or every
6 months, whichever comes
first, using NBS traceable
standard wavelength filter.
Upon receipt, conduct
calibration check.
Adjust using manufac-
turer's instructions, or
return to supplier.
Request calibration check
by manufacturer/supplier.
See Table 2.4.
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Jan. 1983
Section 2.1.2
2.0 Calibration of Equipment
Before beginning the SOa sampling
and analysis, be sure to calibrate the
sampling and analysis equipment. The
calibration activities are summarized
in Table 2.4 at the end of this section.
Many of these calibration checks
should also be used for the initial
procurement activities.
All data and calculations in the
calibration activities should be
recorded in a separate calibration log;
that is, the log should be arranged so
that a separate section is designated
for each calibrated apparatus and
sampler
2.1 Calibration of Flow
Measurement Equipment
The sampling procedure for
determination of SO2 in ambient air
can be implemented by use of one of
two basic sampling trains. The
differences between the two sampling
trains are the flow rate, absorber
design, and flow control system. The
short-term sampling train consists of
all glass midget impingers and utilizes
either a needle valve or critical orifice
to control the flow. Short-term
sampling periods range between 30
minutes and 3 hours and utilize flow
rates of 900 to 1100 cmVmin for 30-
minute samples to 450 to 550
cmVmin for 1- to 3-hour samples.
The long-term sampling train
consists of a polypropylene absorber
tube with a glass impinger stem and
utilizes a critical orifice to control the
flow. The sampling period is 24 hours,
and the flow is between 180 to 220
cmVmin
Although both trains have a flow-
controlling device that must be
calibrated to obtain the appropriate
range for the sampling rate, these
devices cannot be used to measure
the actual sampling flow rate. The
actual sampling flow rate is
determined on site before and after
each sampling period by use of an
appropriate flow-measuring device
that is not part of the sampling train.
Typical flow measuring devices are
wet-test meters, soap-bubble meters,
mass-flow meters, and rotameters—
all of which require calibration.
2.1.1 Wet- Test Meters —
Calibration Check - Wet-test meters
are calibrated by the manufacturer to
an accuracy of ±0.5 percent; the
calibration must be checked initially
(upon receipt) and quarterly thereafter
at standard temperature and pressure
and at the flow rates at which the
meter will be used. The following
liquid positive-displacement technique
can be used to verify and make any
adjustments to the accuracy of the
wet-test meter to ±1 percent.
1. Level the wet-test meter by
adjusting the legs until the bubble on
the top of the meter is centered.
2. Adjust the water volume in the
meter until the pointer in the water
level gauge just touches the
meniscus. Refer to manufacturer's
instructions because some types of
meters may require additional
adjustments.
3. Adjust the water manometer in the
meter to zero by moving the scale or
by adding water to the manometer.
4. Set up the calibration apparatus as
shown in Figure 2.1. Do not attach
the saturator at this time.
a. Fill the 5-gal jug (the reservoir)
with distilled water almost up to the air
inlet tube, and allow it to equilibrate to
room temperature (about 24 h) before
use.
b. Start water siphoning through
the system at a flow rate of
approximately 200 ml/min, and
collect the water in a 1-gal
container located in place of the
volumetric flask (Figure 2.1).
5. Check the physical operation of
the meter. If the manometer reading
is <10 mm (<0.4 in.) H2O, the meter
is in proper working condition.
Continue to Step 6. If it is >10 mm
(0.4 in.) H20, the wet-test meter is
defective. Return it to the
manufacturer for repair if the defect(s)
(e.g., bad connections or joints) cannot
be found and corrected.
6. Attach the saturator and continue
the operation until the 1-gal container
is almost full, and then use a pinch
clamp to turn the siphoning system
off.
7. Read the initial volume (V,) from
the wet-test meter dial, and record it
on the wet-test calibration log (Figure
2.2).
8. Place a clean, dry, 2000-ml
volumetric flask (Class A) under the
siphon tube; open the pinch clamp;
and fill the flask to the 2000-ml mark.
Thermometer
Water
Reservoir
(5-gal jug)
Saturator
Water Out \_=r=-
Level Adjust
TO Valve
2000-ml Line
Volumetric
Flask
(Class A)
Figure 2.1 Calibration check apparatus for wet-test meter.
-------
Section 2.] .2
Jan. 1983
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Jan. 1983
Section 2.1.2
9. Record the manometer reading
while the water is flowing. Also
record the following data:
a. Meter and reservoir air
temperatures, °C (°F),
and
b. Barometric pressure, mm (in.) Hg.
10. When the volumetric flask
reaches its calibrated capacity, read
the final volume (Vf) from the wet-test
meter dial and record. Calculate the
indicated volume measured by the
wet-test meter (Vmina = V( - V,).
11. Repeat steps 7 through 1Q twice.
12. Calculate the volume passing
through the meter (Vmact), using
Equation 2-1, for each test.
,T,,
Equation 2-1
where
Pb = barometric pressure, mm Hg
APm = wet-test meter manometer read-
ing, mm Hg
T, = temperature of reservoir, K = °C +•
273.2
Tm = temperature at wet-test meter,
K = °C + 273.2
Vt = volume measured by volumetric
flask, liters.
An example of this calculation is:
Barometric pressure, Pb = 742.2 mm
Hg
Reservoir temperature, T, = 23.0°C +
273.2 = 296.2 K
Meter temperature, Tm = 22.5°C +
273.2 = 295.7K
Meter manometer reading = 35 mm
•H20
APm = 35 mm HaO x 0.074 mm
Hg/mm HzO = 2.6 mm Hg;
Volume measured by wet test
meter
Vm'nd= 2.020 - 0.005 = 2.015 liters.
Volume measured by volumetric
flask, V. = 2.0000 liters
Corrected volume at meter condi-
tions:
VmMl = / 295.7 \ 2.000 = 1.9966 liters.
V296.2 /
13. Calculate the relative percent
error as follows:
% error =
100 =
(2.01 S-1.9966
V 1.9966 /
Equation 2-2
The error should not exceed ±1
percent. If it does, check all
connections within the test apparatus
for leaks; gravimetrically check the
volume of the standard flask; and
repeat the calibration procedure. If the
tolerance level is still not met, adjust
the liquid level within the meter until
the specifications in the
manufacturer's manual are met or
return the meter to the manufacturer.
Use of the wet-test meter for the
calibration of flow rate devices such
as rotameters and mass-flow meters
requires corrections for temperature,
barometric pressure, and possibly the
vapor pressure of the water. If the
device to be calibrated is placed after
the wet-test meters (as shown later in
Figure 2.5), no correction for the
vapor pressure of water is required.
Equation 2-3 is presented to assist
the user with these corrections to the
standard conditions of 760 mm (29.92
in.) Hg, 25°C (77°F), and 0 percent
water vapor.
Flow rate at standard conditions
= vol(ml) XP- Pvx 298
time (min) 760 273 + T
Equation 2-3
where
P= atmospheric pressure, mm Hg,
Pv= vapor pressure of water (see Table
2.1 on next page) mm Hg, and
T= temperature of gas, °C
Example: Assume the temperature to
be 20°C and the atmospheric
pressure to be 710 mm Hg.
Flow rate at standard conditions
= vol(ml) V710- 17.54X 298
time (min) 760 273 + 20
= vol(ml) x 0.927 = ml/min.
time (min)
2.1.2 Soap -Bubble Meter -
Calibration checks - Soap-bubble
meters calibrated by the manufacturer
to an accuracy of ±0.25 percent are
commercially available; the volume of
each of these soap-bubble meter tubes
is traceable to a National Bureau of
Standards (NBS) displacement
volume. Frequently, however, soap-
bubble meters are constructed in the
laboratory by use of a burette of
appropriate volume.
Two calibration methods are
commonly used for soap-bubble
meters: (1) the volume-displacement
method described for the wet-test
meter, and (2) the volume-
displacement method measured
gravimetrically. The gravimetric-
displacement method requires less
effort than the volume-displacement
method. The displacement volume of
a soap bubble meter does not change
with use; therefore, it requires only
initial calibration upon receipt from
the manufacturer. The soap-bubble
meter can be used only within the
volume range for which it was
calibrated. A calibration procedure by
the gravimetric method is presented
here.
1. Secure a clean displacement
tube to a ringstand, and attach a
stopcock to the bottom (as shown in
Figure 2.3).
Soap-Bubble Meter Tube
Displacement Volume
Stopcock
Ground-Glass
\ Stoppered Flask
r
Figure 2.3
Test apparatus for soap-
bubble meter.
2. Obtain an appropriately sized and
stoppered groundglass volumetric
flask that will contain the volume of
the displacement tube of the soap-
bubble meter.
3. Determine the weight of the
flask and the stopper to the following
specifications:
a. 10-ml flask - weigh to the nearest
0.001 g
b. 100-ml flask - weigh to the
nearest 0.01 g
c. 1000-ml flask - weigh to the
nearest 0.1 g
Record the weight on the calibration
log. Figure 2.4; a blank form for the
Handbook user is in Section 2.1.13.
4. Fill the displacement tube with
distilled water, drain the system until
all air bubbles are removed, and
collect the water in a beaker and
discard it.
5. Fill the displacement tube so that
the bottom of the meniscus is at the
top mark.
6. Determine the temperature of
the water within the displacement
tube, and record it in the log.
-------
Section 2.1.2
Jan. 1983
Table 2.
Temp
°C
— 15
— 14
— 13
— 12
— 11
-10
— 9
— 8
— 7
— 6
— 5
4
— 3
— 2
— 1
— 0
0
1
2
3
4
5
6
7
8
9
JO
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
1 Saturation Vapor Pressure Over Water (°C, mm Hgl
(Values for fractional degrees between 50 and 89 obtained by interpolation)
Temp
0.0 0.2 0.4 0.6 0.8 °C 0.0 0.2 0.4
1.436
1.560
1.691
1.834
1.987
2.149
2.326
2.514
2.715
2.931
3.163
3.410
3.673
3.956
4.258
4.579
4.579
4.926
5.294
5.685
6.101
6.543
7.013
7.513
8.045
8.609
9.209
9.844
10.518
11.231
11.987
12.788
13.634
14.530
15.477
16.477
17.535
18.650
19.827
21.068
22.377
23.756
25.209
26.739
28.349
30.043
31.824
33.695
35.663
37.729
39.898
42.175
44.563
47.067
49.692
1.414
1.534
1.665
1.804
1.955
2.116
2.289
2.475
2.674
2.887
3.115
3.359
3.620
3.898
4.196
4.513
4.647
4.998
5.370
5.766
6.187
6.635
7.111
7.617
8.155
8.727
9.333
9.976
10.658
1 1.379
12. 144
12.953
13.809
14.715
15.673
16.685
17.753
18.880
20.070
21.324
22.648
24.039
25.509
27.055
28.680
30.392
32.191
34.082
36.068
38. 155
40.344
42.644
45.054
47.582
50.231
1.390
1.511
1.637
1.776
1.924
2.084
2.254
2.437
2.633
2.843
3.069
3.309
3.567
3.841
4.135
4.448
4.715
5.070
5.447
5.848
6.274
6.728
7.209
7.722
8.267
8.845
9.458
10. 109
10.799
1 1.528
12.302
13.121
13.987
14.903
15.871
16.894
17.974
19.113
20.316
21.583
22.922
24.326
25.812
27.374
29.015
30.745
32.561
34.471
36.477
38.584
40.796
43.117
45.549
48. 102
50.774
1.368
1.485
1.611
1.748
1.893
2.050
2.219
2.399
2.593
2.800
3.022
3.259
3.514
3.785
4075
4.385
4.785
5.144
5.525
5.931
6.363
6.822
7.309
7.828
8.380
8.965
9.585
10.244
10.941
11.680
12.462
13.29O
14.166
15.092
16.071
17.105
18.197
19.349
20.565
21.845
23. 198
24.617
26.117
27.696
29.354
31.102
32.934
34.864
36.891
39.018
41.251
43.595
46.050
48.627
51.323
1.345
1.460
1.585
1.720
1.863
2.018
2.184
2.362
2.553
2.757
2.976
3.21 1
3.461
3.730
4.016
4.320
4.855
5.219
5.605
6.015
6.453
6.917
7.411
7.936
8.494
9.086
9.714
10.380
11.085
1 1.833
12.624
13.461
14.347
15.284
16.272
17.319
18.422
19.587
20.815
22. 1 10
23.476
24.912
26.426
28.021
29697
31.461
33.312
35.261
37.308
39.457
41.710
44.078
46.556
49. 157
51.879
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
61.50
64.80
68.26
71.88
75.65
79.60
83.71
88.02
92.51
97.20
102.09
10720
112.51
118.04
1 23.80
129.82
136.08
142.60
149.38
156.43
163.77
171.38
179.31
187.54
196.09
204.96
214.17
223. 73
233.7
243.9
254.6
265.7
277.2
289.1
301.4
314.1
327.3
341.0
355.1
369.7
384.9
400.6
416.8
433.6
450.9
468.7
487.1
506.1
525. 76
546.05
566.99
588.60
610.90
633.90
657.62
682.07
707.27
62.14
65.48
68.97
7262
76.43
80.41
84.56
88.90
93.5
98.2
103.1
108.2
113.6
119 1
125.0
131.0
137.3
143.9
150.7
157.8
165.2
172.9
180.9
189.2
197.8
206.8
216.0
225.7
235.7
246.0
256.8
268.0
279.4
291.5
303.8
316.6
330.0
343.8
358.0
372.6
388.0
403.8
420.2
437.0
454.4
472.4
491.0
510.0
529.77
550. 18
571.26
593.00
615.44
638.59
662.45
687.04
712.40
62.80
66.16
69.69
73.36
77.21
81.23
85.42
89.79
94.4
99.1
104.1
109.3
114.7
120.3
126.2
132.3
138.5
145.2
152.1
159.3
166.8
174.5
182.5
190.9
199.5
208.6
218.0
227.7
237.7
248.2
259.0
270.2
281.8
294.0
306.4
319.2
332.8
346.6
361.0
375.6
391.2
407.0
423.6
440.4
458.0
476.0
494.7
513.9
533.80
554.35
575.55
597.43
620.01
643.30
667.31
692.05
717.56
0.6
63.46
66.86
70.41
74.12
78.00
82.05
86.28
90.69
953
100.1
105.1
110.4
115.8
121.5
127.4
133.5
139.9
146.6
153.5
160.8
168.3
176.1
184.2
192.6
201.3
210.5
219.9
229.7
239.7
250.3
261 2
272.6
284.2
296.4
308.9
322.0
335.6
349.4
363.8
378.8
394.4
410.2
426.8
444.0
461.6
479.8
498.5
517.8
537.86
558.53
579.87
601.89
624.61
648.05
672.20
697. 10
722. 75
0.8
64.12
6756
71.14
74.88
78.80
82.87
87.14
91.59
96.3
101.1
106.2
111.4
116.9
122.6
128.6
134.7
141.2
148.0
155.0
162.3
169.8
177.7
185.8
194.3
203.1
212.3
221.8
231.7
241.8
252.4
263.4
274.8
286.6
298.8
311.4
324.6
338.2
352.2
366.8
381.8
397.4
413.6
430.2
447.5
465.2
483.4
502.2
521.8
541.95
562.75
584.22
606.38
629.24
652.82
677. 12
702.17
727.98
-------
Jan. 1983
Section 2.1.2
Table 2.1 (continued) Saturation Vapor Pressure Over Water (°C, mm Hgj
(Values for fractional degrees between SO and 89 obtained by interpolation)
Temp Temp
°c
39
40
41
0.0
52.442
55.324
58.34
0.2
53.009
55.91
58.96
0.4
53.580
56.51
59.58
0.6
54. 156
57.11
60.22
0.8
54.737
57.72
60.86
°C
99
100
101
0.0
733.24
760.00
787.57
0.2
738.53
765.45
793. 18
0.4
743.85
770.93
798.82
0.6
749.20
776:44
804.50
0.8
754.58
782.00
810.21
Mptpr serif*/ n^rnhf^r
D/Sp/3CGI71Gnt VOiUfTIG*
/fX> ML.
n.,. Z/27/W
Calibrated by <^~'D
-------
Section 2.1.2
Jan. 1983
11. Compute_the average displace-
ment volume (Vd) from the three tests:
Vd =
Equation 2-5
12. Compute the percent error as
follows'
% error
100
Equation 2-6
where V is the displacement volume
(ml) stated by the manufacturer. The
example calculation of % error below
assumes that V = 100 ml and Vd =
100.267:
=/100- 100.267\
V 100.267 /
%Brrnr
100.267
x 100 = -0.27%.
The error should not exceed ±1
percent.
Use of the soap-bubble meter for
the calibration of flow rate devices
such as rotameters and mass-flow
meters requires corrections for
temperature, barometric pressure,
and the vapor pressure of the soap
bubble (which is considered to be the
vapor pressure of water). Equation 2-3
is repeated here to assist the user
with these corrections to the standard
conditions of 760 mm (29.92 in.) Hg,
25°C (77°F), and 0% water vapor.
Flow rate at standard conditions
= vol(ml) yP_-P,
time (min) 760
298
273 + T
Equation 2-3 (repeated)
where
P =atmospheric pressure, mm Hg
Pv = vapor pressure of water (see Table
2.1), mm Hg
T = temperature of gas, °C
Example: Assume the temperature to
be 20°C and the atmospheric pressure
to be 710 mm Hg
Flow rate at standard conditions
= vol(ml) y710- 17.54* 298
time (min) 760 273 + 20
= vol(ml) x Q.927 = ml/min.
time (min)
2.1.3 Mass-Flow Meter Calibration
Check - Mass-flow meters operate
on a thermal principle that depends
on the mass flow of the gas and on its
heat capacity to gauge the
temperature within a heated conduit.
Because these meters measure the
true mass flow, they have the
advantage of not requiring corrections
for changes of temperature and
pressure. Flow rate values are usually
given in standard cubic centimeters of
air per minute, which are measures of
the volume occupied by a mass of air
at standard temperature and pressure,
as specified by the manufacturer
Mass-flow meters are not volume
displacement devices; therefore, they
require calibration at least quarterly
against a displacement device such as
a bubble meter or a wet-test meter,
which serves as a secondary
calibration standard. Before
calibration of a mass flow meter
against an already calibrated wet test
meter, reference should be made to
the manufacturer's instructions for
the flow rate capacity. The following
procedure should then be used.
1. Be sure that the mass flow
meter is off. Use the adjustment
screw below the meter face to set the
pointer needle on zero.
2. Turn the meter on, and allow it
to warm up for 1 h.
3. After the warmup period, adjust
te electronic zero as follows:
a. Plug the inlet and the outlet of
the transducer.
b. Use the adjust screw to set the
electronic zero on the meter.
c Unplug the ends of the
transducer before connecting it to the
test apparatus (as illustrated in Figure
2.5).
4. Turn the vacuum pump on, and
use the needle valve to adjust the
flow rate to approximately 75 percent
of the full scale of the mass-flow
meter.
5. Allow the system to equilibrate
for approximately 10 revolutions of
the wet-test meter.
6. Read the manometer on the wet-
test meter in mm H2O; convert to mm
Hg (mm H2O x 0.0738 = mm Hg); and
record the Apm on the calibration log
(Figure 2.6). Because the air passing
through the calibration apparatus has
been presaturated, no correction for
water vapor is necessary
7. As the wet-test meter pointer
passes zero, use a precision
stopwatch to begin the timing. As the
wet-test meter pointer passes the
three-quarter revolution mark, take a
reading and record the mass-flow
meter reading in the log. As the wet-
test meter pointer passes the starting
point, stop the stopwatch and record
the elapsed time (t).
8. Record the wet-test meter
volume in the column headed by Vm,
and record the wet-test meter fluid
temperature (Tm) in K.
9. Calculate Pm = Pb - APm and use
Equation 2-7 to calculate Vs by using
the recorded value of Pm, Tm, and Vm;
Ts = 298 K and Ps = 760 mm Hg.
Record the V5 value.
Vs =
PsTm /
2-7
Mass-Flow
Meter Face
Thermometer \-
Air Inlet
Figure 2.5 Mass-flow meter calibration apparatus.
-------
Jan. 1983
Section 2.1.2
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Section 2.1.2
Jan. 1983
where
Pm= Pb - APm = measured
barometric pressure corrected
for internal meter pressure, mm
Hg
Ps= pressure at standard
conditions, 760 mm Hg
Tm= measured temperature of
air, K
Ts= temperature at standard
conditions, 25°C = 298 K and
Vm= measured volume from wet
test meter.
10. Calculate the flow rate (Qs)
from Vs and t:
Qs= Vs. Equation 2-8
t
where
Qs = flow rate at standard
conditions, liters/mm
Vs= volume of gas at standard
conditions, liters
t= time, mm.
Record Qs.
11 Plot Qs versus the mass-flow
meter readings on rectangular graph
paper.
12. Repeat Steps 6 through 11 for
five other flow rates within the range
of the mass-flow meter.
13. Construct a best-fit curve for
the points generated, and use this
relationship for future work using the
mass-flow meter.
2.1.4 Calibration of Rotameter - A
commonly used method for measuring
gas flow rates is the rotameter or
variable-area flow meter. It is usually
a round glass tube housing one or
more floats that are free to move
vertically up and down the tube axis
On the sides are reference marks,
which may be either linearly or
exponentially inscribed on the tube
As the gas flows up the tube, the float
is displaced and continues to move
upward until equilibrium is reached
This.occurs when the gravitational
force of the float equals the buoyant
force of the moving gas stream.
Float design will vary depending on
the manufacturer and the flow rate
desired. Most lower-range rotameters
use spherical floats. Readings are
conventionally taken at the widest
point of the float.
Although the manufacturer
generally provides reasonably
accurate calibration curves,
rotameters should be recalibrated at
the conditions that will be used
Rotameters separate from the tram
used as flow measuring devices must
be calibrated against a previously
calibrated wet-test meter, soap bubble
meter, or mass-flow meter.
Rotameters can be calibrated by use
of a bubble meter as a secondary
standard as follows'
1 Assemble the equipment as
shown in Figure 2.7. Note
Rotameters calibrated in a vacuum
situation should be used only in a
similar (vacuum) situation.
2 Read and record room
temperature and barometric pressure
on the rotameter calibration data form
(Figure 2 8 on following page).
3 Turn on vacuum pump
4 Adjust the needle valve until the
rotameter float is about 20 percent of
full scale
5 Touch the surface of the soap
solution with the open end of the
bubble meter so that a soap bubble
will start to travel up the bubble meter
tube. Repeat several times or until
bubbles will travel the full length of
the tube without breaking.
6 Touch the surface of the soap
solution with the open end of the
bubble meter so that a single bubble
starts to travel up the bubble tube
When the bubble passes the first line
of graduated scale, start stopwatch
Record time and volume displaced.
7. Repeat Step 6 two more times
Record time and volume each time.
8. Calculate average time and
volume displacement for three runs.
9. Correct average volume
displacement to standard conditions of
760 mm Hg and 25°C by use of
Equation 2-9,
Vs=Vn
Equation 2-9
Bubble
Trap
where
Vm= measured volume from bubble
meter, ml
Pb= barometric pressure, mm Hg
Pv= vapor pressure of water in
soap bubble meter at the
temperature employed, mm Hg
(see Table 2.2)
Ps= pressure at standard conditions
= 760 mm Hg
Ts= temperature at standard
conditions, 298 K
Tm= temperature of soap bubble
meter, K.
10. Divide the corrected volume
displacement by the average time to
determine the flow rate.
11. Repeat Steps 4 through 10 for
each of five or more uniformly spaced
points on the rotameter scale, going
from low values to high values.
1 2. Plot the rotameter units versus
the flow rate Qs on linear graph
paper, constructing a best fit smooth
curve through the data points by use
of a flexible rule A typical calibration
relationship is presented in Figure
2.9. All data points should be within
±2 percent of the curve of best fit.
13 Should the rotameter be used
in a field location where the
barometric pressure and/or
temperature is different than those
conditions when the rotameter was
calibrated, the following corrections
must be applied to convert the flow
rate to standard conditions. This
correction factor is not advisable for
conditions that differ greatly from
those at which the rotameter was
calibrated Greater accuracy can be
obtained by developing calibration
Surge Tank
(Volume, 0.25-0.5 Liters)
Beaker with
Soap Solution
Vacuum
Pump
Needle
Valve
Stopwatch
Figure 2.7 Rotameter calibration apparatus.
* Volume tubes available 10 ml to 1000 ml
-------
Jan. 1983
Section 2.1.2
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-------
Section 2.1.2
10
Jan. 1983
Table2.2 Absolute Density of Water
Temp, °C
(Values numerically equal to absolute density of Hz
Density, g/ml Temp, °C
Density, g/ml
15
16
17
18
19
20
21
22
23
24
0.99913
0.99887
0.99880
0.99862
0.99843
0.99823
0.99802
0.99780
0.99756
0.99732
25
26
27
28
29
30
31
32
33
34
0.99707
0.99681
0.99654
0.99626
0.99597
0.99567
0.99537
0.99505
0.99473
0.99440
300
250
200
£ 150
|
i£
100
50
Flow Meter Serial No.
Location
Temperature (°C),
Atmos. Pressure^fmm Hg,
Calibrated by
0.2
0.4
0.6 0.8 1.0 1.2 1.4
Flow rate at STP fQsJ,, l/min
Typical rotameter calibration curve.
1.6
1.8
2.0
Figure 2.9
curves for expected conditions.
__
\760 T,
where
Equation 2-10
Qt= flow rate at field conditions
from calibration curve, ml/min
Pf= barometric pressure at field
conditions, mm Hg
Ti= temperature at field conditions,
K.
2.2 Sampling Train Flow
critical orifices used as flow-control
devices in the SOz sampling trains
should be checked for the appropriate
range of sampling rates, but they do
not require strict calibration because
their values cannot be used to
determine the sample volume. The
sample volume is determined from the
sampling time and the sample flow
rate measured before and after
sampling by use of a flow
measurement device connected to the
inlet of the absorber.
Flow rate requirements for different
sampling periods and typical
hypodermic, needle sizes that will give
these flow rates are:
1. 30 minutes of sampling at 0.9 to
1.1 liters/min. Use a 1-inch 22-gauge
hypodermic needle.
2. One hour of sampling at 450 to
550 cmVmin. Use a 5/8-inch, 23-
gauge, hypodermic needle.
3. 24-hours of sampling at 180 to
220 cmVmin Use a 3/8-inch 27-
gauge, hypodermic needle.
In the short-term sampling train
only, a rotameter and needle valve
covering the appropriate range may be
used.
The flow control devices in the
assembled sampling train should be
checked to ensure that the
appropriate range can be obtained
before they are taken into the field.
Any needle unable to give the
accepted range should be discarded.
The flow rates are checked by use of
the procedures described for
determining the flow rates before and
after sampling in Section 2.1.4,
Subsection 4 4.
Constant flow rates through
hypodermic needles can be achieved
only when critical flow conditions are
met. These conditions exist when the
absolute pressure downstream of the
needle (Pd) is <0.45* of the absolute
pressure upstream of the needle
(Pu)—that is, when Pd <0.45 Pu. For
the SOa sampling trains, the upstream
pressure (Pu) is usually 25 mm (1.0
in.) Hg less than the barometric
pressure, and the downstream
pressure (Pd) is equal to the
barometric pressure minus the
pressure from the vacuum gauge (PQ).
Since the barometric pressure
decreases with altitude, the critical
flow conditions are satisfied at lower
vacuum gauge readings at higher
altitudes. Vacuum gauge readings for
critical flows at several altitudes are
shown in Table 2.3. A minimum safety
Q.= flow rate corrected to standard Control Devices
conditions from field conditions, The rota meters and needle valves
ml/min
(short-term sampling only) or the
•Reference 8 of the Reference Method, Section
2111, verifies the 0 45 for use with the
hypodermic needle Reference 5 of Section
2.1.12 gives 053 as a purely theoretical value.
-------
Jan. 1983
11
Section 2.1.2
Table 2.3 Vacuum Gauge Readings to Achieve Critical Flow for Various Elections
(Assumed pressure drop across samp/ing train = 25 mm (1.0 in.) Hg)
Elevation Standard Gauge reading
above sea level barometric pressure . for critical flow
m
0
305
610
915
1220
1525
1830
ft
0
WOO
2000
3000
4000
5000
6000
mm Hq
760
732
706
680
656
632
609
in. Hg
29.9
28.8
27.8
26.8
25.8
24.9
24.0
mm Hg
429
414
399
385
372
359
346
in. Hg
16.9
16.3
15.7
15.2
14.6
14.1
13.6
factor of 20 percent of the gauge
reading should be added to the table
values to ensure critical flow during
the total sampling period
Flow rates through hypodermic
needles used as critical orifices are
directly affected by upstream
pressures, which are in turn affected
by barometric pressures. Care must
be exercised when needles are used
at elevations that differ greatly from
that at which they were checked.
2.3 Calibration of Analytical
Balance
The balance calibration should be
verifed when the balance is (1) first
iurchased, (2) any time it is moved or
'subjected to rough handling, and (3)
during routine operations when a
standard weight cannot be weighed
within ±0.5 mg of its stated weight. If
at any time, one or more of the
standard weights cannot be measured
within ±0.5 mg of its stated value, the
manufacturer should be asked to
recalibrate and adjust the balance.
The results of all balance checks
should be recorded in the log (Figure
2.10).
2.4 Calibration of E lapsed-
Time Meter
The elapsed-time meter
(synchronous motor, type 60 Hz)
should be checked on site or in the
laboratory every 6 mo against a
timepiece of known accuracy. If the
indicator shows any signs of being
temperature-sensitive, it should be
checked on site during each season of
the year; a gain or loss of more than 2
min in a 24-h period warrants an
adjustment or replacement of the
indicator. Results of these checks
should be recorded in the calibration
log.
2.5 Calibration of On-Off
Timer
The on-off timer should be
calibrated and adjusted by using an
already-calibrated elapsed-time meter
as the reference. The calibration
procedure should be performed
quarterly, and the calibration data
should be recorded in the timer log.
(See Figure 2.11 for an example and
Section 2.1 13 for a blank form.) An
example calibration procedure is
presented below.4 Figure 2.12 is a
wiring diagram for the calibration.
1. Plug a correctly wired timer into
an electrical outlet.
2, Set the timer to the correct time.
3. Set the on and the off time
trippers for the 24 h.
4. Plug the test light into one of the
output plugs, and plug an elapsed-
time meter into the other
5. Check the system by manually
operating the switch on and off.
6. Allow the system to operate for
the 24-h period, and determine the
elapsed time from the elapsed-time
meter. If the elapsed time is 24 h ±15
mm, the timer is acceptable for field
use; if not, adjust the tripper switches,
and repeat the test.
-------
Section 2.1.2
12
Jan. 1983
Analytical Balance Quality Control Log
Date
7/29/74
7/29/74
7/29/74
7/30/74
7/31/74
7/31/74
7/31/74
7/31/74
7/31/74
8/1/74
8/1/74
8/1/74
8/1/74
8/1/74
8/1/74
8/1/74
8/2/74
8/2/74
8/2/74
8/2/74
8/2/74
8/2/74
8/2/74
8/3/74
8/3/74
8/5/74
8/5/74
8/5/74
8/5/74
8/5/74
8/5/74
8/5/74
8/6/74
8/6/74
8/6/74
8/6/74
8/6/74
8/6/74
8/7/74
8/7/74
8/7/74
8/7/74
8/7/74
8/8/74
9/24/74
9/26/74
Time
11.07
1208
2.40
4:03
957
1056
11-57
204
305
9:03
10.05
11:10
12:12
1 43
2:42
345
8:54
9-56
1059
12-16
1 55
303
400
8-41
11 16
8.42
945
1044
11.46
1:16
221
315
9-37
11 05
12-10
2 10
3:09
405
8:50
9:46
1-10
2:20
325
9:46
3.50
3:01
Class S Weights (qj
0.5000
05000
0.5002
05000
0.4996
0.4994
04995
0.4994
0.5001
0.5000
0.4998
04993
0.5000
0.4998
0.5000
0.5001
05001
0.5000
05000
0.5003
0.5001
0.4990
05000
0.5000
04999
0.5002
0.5001
05000
0.5000
0.5000
05001
0.5001
0.5000
0.4999
0.5000
0.4999
0.5000
05000
0.5000
0.5000
0.4996
05001
0.5001
0.5002
0.5000
0.5001
0.5001
1 0000
1 0002
1 0003
1 0000
09999
1 0000
09992
09994
1 0000
1.0000
09992
09992
1.0001
09997
1 0001
1 0001
1.0000
1 0001
1 0000
09999
1.0002
1 0002
0.9999
09998
09996
1.0002
1.0000
1 0000
1.0000
1.0001
1 0000
1.0000
1 0000
1.0000
0.9998
09998
0.9998
1 0000
1 0000
1 0002
0.9992
1 0000
1 OOOO
1.0001
1.0000
1 0001
7.0007
20000
20000
2000?
73393
20002
20000
7 9993
79994
2.0002
20000
7 9992
7 9992
20007
7 9933
20002
20007
20007
20007
2.0007
7 9998
20002
20001
20001
79999
7 9995
2.0002
20000
20000
2.0000
20000
2.0000
2.0007
20007
2.0000
7.9994
7 9999
20000
20000
20000
20003
7 9990
20000
2.0000
2.0000
20000
20007
20007
Technician
BSM
DEK
DEK
JLK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
Figure 2.10 Example of an analytical balance performance record.
-------
Jan. 1983
13
Section 2.1.2
,<0 <0
8.H
£ o
11;
II
II *i
Uj
w S
If
o-S-S
5li
o
o
8
Q
-------
Section 2.1.2
14
Jan. 1983
On-Off Timer
f+15 mm/24 hi
Indicator Lamp
Elapsed- Time Meter
(+2 mm/24 h>
Figure 2.12 Diagram of a timer calibration system.
Table 2.4 Activity Matrix for Calibration of Equipment
Equipment
Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
Wet-test meter
Soap-bubble meter
Mass-flow meter
Rotameter
Flow control devices, rota-
meter and needle value or
hypodermic needles
Analytical
balance
Elapsed-time meter
On-off timer
%error<1%(Fig22)
% error <1% (Fig 2.4)
All data points within ±2%
of best-fit curve
As above
Appropriate range for
sampling period: rotameter,
450 to 1100 cm3/min;
orifices, 900 to 1100 cm2/
min. 30-min sampling, 450
to 550 cm3/mm, 1 - to 3-
hour sampling, 180 to 220
cm3/'min, 24-hour
sampling
Standard weights ±0,5 mg
of stated values
±2 min/24 h
±15 min/24 h
Check upon receipt and
quarterly with liquid
positive displacement
(Subsec 2.1.1).
Calibrate upon receipt from
manufacturer with gravi-
metric displacement
(Subsec 2.1.2).
Calibrate quarterly with
bubble or wet test meter
(Subsec 2.1.3).
Calibrate quarterly with
bubble meter (Subsec.
2.1.4).
Check flow rate initially
and before and after each
sampling period with cali-
brated flow measuring
device.
Verify calibration when
first purchased, after
moving or rough handling,
and when a standard
weight is not within ±0.5
mg of stated value.
Check every 6 mo with
timepiece of known
accuracy.
Use calibrated elapsed-
time meter quarterly
fSubsec 2.4).
Adjust by manufacturer's
instructions, or return to
manufacturer.
As above
As above
As above
Clean or rep/ace rotam-
eter; discard hypodermic
needles.
Repeat check to verify
malfunction; have man-
ufacturer recalibrate and
adjust as needed.
Adjust or replace.
Adjust the tripper switches;
repeat test.
-------
Jan. 1983
Section 2.1.3
3.0 Preparation of Reagents
The quality control functions for
preparation of reagents are
summarized in Table 3.1 at the end of
this section.
3.1 Distilled Water
The standard specification for
reagent water is described in the
ASTM designation D 1193-72; this
document requires the Type-ll grade
of water, which is prepared by use of
a still designed to produce a distillate
having a conductivity of <1.0
micromho/ cm at 25°C (77°F) and a
pH range of 6.6 to 7.2.
The following purity test should be
performed after each lot of water
reagent is prepared if the slope and
intercept of the standard curve fail to
meet the specified criteria (Section
2.1.5).
1. Add 0.20 ml of a potassium
permanganate (KMnCU) solution
(0.316 g KMnO4/liter) to a mixture of
500 ml of distilled water and 1 ml of
sulfuric acid (H2S04) in a stoppered
bottle made of chemically resistant
glass. If the KMn04 color (pink) does
not disappear completely after
standing for 1 h at room temperature,
the water is suitable for use; if the
color disappears, the water must be
purified before using.
2. Water that fails the purity test
can be purified as follows:
a. Add 1 g each of KMnO* and
barium hydroxide (BaOH) for each liter
of distilled water.
b. Redistill the water in an all-glass
still.
c. Perform the test for purity
described above.
3. Repeat both the purification
procedure and the test for purity until
the slope and the intercept of the
standard curve meet the specified
limits.
4. Store the reagent water in an
inert container with a vent guard. (A
suitable guard is a drying tube filled
with equal parts 8-20 mesh soda
lime, oxalic acid, and 4-8 mesh
calcium chloride separated from each
other by a glass-wool plug.) Replace
the vent guard drying materials every
30 days.
3.2 Absorbing Reagent
3.2.1 Reagent Preparation - The
0.04M potassium tetrachloromercu-
rate (TCM) absorbing reagent should
be prepared according to the following
procedure.
1. Dissolve 10.86 g of mercuric
chloride, 0.066 g EDTA
(ethylenediaminetetraacetic acid
disodium salt) and 6.0 g of potassium
chloride in distilled water, and dilute
to 1 liter. Usually it is necessary to
prepare larger quantities of the
absorbing reagent to meet the
sampling requirements of the agency.
Warning: The reagent is highly
poisonous. Rubber gloves should be
worn when preparing the absorbing
reagent. If spilled on the skin, it must
be flushed off with water immediately.
2. Label the reagent bottle, and
include the date of preparation.
3.2.2 Reagent pH Test - For each lot
of absorbing reagent prepared for
sampling, the following pH test
procedure should be conducted.
1. Standardize the pH meter with
buffer solutions of pH 4.0 and pH 7.0.
2. Measure the pH of the absorbing
reagent. The optimal pH is 4.0.
3. Discard the reagent if the pH is
<3.0 or >5.0. Dispose of the
absorbing solution according to one of
the disposal techniques described in
Section 2.1.5, Subsection 5.5.
3.2.3 Reagent Storage - The
absorbing reagent should be stored in
a toppered container, and the reagent
should be discarded if it is >6 mo old
(normally stable for 6 mo). It should
be visually examined before each use
and discarded if a precipitate is
visible. The absorbing solution should
be discarded in accordance with one
of the disposal techniques described
in Section 2.1.5, Subsection 5.5.
3.3 Sulfamic Acid (0.6%)
Sulfamic-acid (0.6 g) should be
dissolved in a 100-ml volumetric flask
with water and diluted to the 100-ml
mark. The solution should be kept in a
glass- stoppered flask while not in
use, and it should be prepared fresh
daily.
3.4 Formaldehyde (0.2%)
Five milliliters (5 ml) of formaldehyde
solution (36-38%) should be diluted to
1000 ml with distilled water. The
0.2% solution should be kept in a
stopped container while not in use,
and it should be prepared fresh daily.
3.5 Starch Indicator
Solution
A starch solution for iodimetric
determinations should be prepared by
following these three steps:
1. Triturate 0.4 g of soluble starch
and 0.002 g mercuric iodide
(preservative) with a small amount of
water to form a paste.
2. Add the paste slowly to 200 ml
of boiling water, and continue the
boiling until the solution is clear.
3. Allow to cool, and transfer to a
glass-stoppered bottle.
Alternatively, a solution of stabilized
starch for iodimetric determinations
can be purchased commercially.
3.6 Stock Iodine Solution
(0.1N)
The procedure for preparing the 0.1
N iodine solution is as follows.
1. Place 12.7 g of iodine in a 250-ml
beaker.
2. Add 40 g of potassium iodide (Kl)
and 25 ml of water to the beaker.
3. Stir until dissolved.
4. Transfer the contents of the
beaker to a 1000-ml flask, and dilute
to the mark with distilled water. Keep
the stock solution in a glass-stoppered
dark bottle, and store in a cool place.
3.7 Working Iodine Solution
(0.01 N)
The approximately 0.01N iodine
solution should be prepared by
diluting 50 ml of the 0.1N stock
solution to 500 ml with distilled
water. The 0.01N working solution
should be kept in a glass-stoppered
dark bottle or dark flask, and it should
be prepared fresh daily.
3.8 Hydrochloric Acid (IN)
The solution of 1N HCI should be
prepared by slowly adding 86 ml of
concentrated HCI (12N) to 500 ml of
distilled water. After it has been
allowed to cool, it should be diluted to
1000 ml with distilled water.
3.9 Stock Sodium
Thiosulfate Solution (0.1N)
A 0.1N stock solution should be
prepared by dissolving 25 g of sodium
thiosulfate (Na2S203 • 5H2O) in 100 ml
of freshly boiled but cooled distilled
water and by adding 0.1 g of sodium
carbonate to the solution. The solution
-------
Section 2.1.3
Jan. 1983
should be allowed to stand 1 day
before standardizing.
The procedure for standardizing
against a potassium iodate (KI03)
standard before each use is as
follows:
1. Dry ACS reagent grade KI03 at
180°C (356°F) for 3 h in a drying
oven.
2. Cool the dried KIOs in a
desiccator.
3. Weigh and record the weight to
the nearest 0.1 mg of the 1 5 g of the
dried cooled KIOs.
4. Add the weighed sample of KI03
to a 500-ml volumetric flask, and
dilute to the 500-ml mark.
5. Pipette 50 ml of the KIOs solution
into a 500-ml flask; add 2 g of Kl and
10 ml of 1N hydrochloric acid (HCI).
6. Stopper the flask and wait 5 min
before titrating to a pale yellow with
the 0.1 N stock thiosulfate solution.
7. Add 5 ml of a starch indicator
solution, and continue the titration
until the blue color disappears.
8. Calculate the normality (Ns) by
using the following equation:
N,=WX2.80
M
Equation 3-1
where
N,= normality of stock thiosulfate
solution
W= weight of KIOs, g
M= volume of thiosulfate required,
ml
2.80 =.
0.1 (KIO3fractionused)x103
(convert g to mg).
35.67 (equivalent weight of KIO3)
Store the 0.1N sodium thiosulfate
stock solution in a glass-stoppered
flask.
3.10 Sodium Thiosulfate
Titrant (0.01 N)
The 0.1 N stock thiosulfate solution
(100 ml) should be accurately pipetted
into a 1000-ml volumetric flask and
diluted to the mark with freshly boiled
but cooled distilled water. This 0.01 N
solution is not stable, and must be
prepared fresh daily from the stock
thiosulfate solution. It should be kept
in a glass-stoppered flask or bottle
when not in use. The normality of the
sodium thiosulfate titrant (NT) should
be calculated as follows:
NT = Nsx 0.100
Equation 3-2
3.11 Standard Sulfite-TCM
Solution
This solution is prepared by
dissolving 0.30 g of sodium
metabisulfite (NazSzOs) or 0.40 g of
sodium sulfite (NazSOs) in 500 ml of
freshly boiled but cooled distilled
water. (Because sulfite solution is
unstable, water of the highest purity
should be used to minimize the
instability.) This solution contains the
equivalent of 320 to 400//g SO2/ml;
the actual concentration is determined
by adding excess iodine and by back-
titrating with the 0.01 N standard
sodium thiosulfate solution. The
working sulfite-absorbing reagent
solution (see Subsection 3.12) should
be prepared while the iodine solution
is being added to the flasks.
The procedure for standardizing the
sulfite solution is as follows:
1. Label each of three 500-ml
flasks with an A, and label three other
flasks with a B.
2. Pipette 50 ml of the 0.01
working iodine solution into each of
the six labelled 500-ml flasks.
3. To each A flask (blank), add 25
ml of distilled water; to each B flask
(sample), pipette 25 ml of the
standard sulfite solution.
4. Stopper the flasks, and allow the
solutions to react for 5 min.
5. Use a 50-ml burette containing
standardized 0.01 N thiosulfate to
titrate each flask to a pale yellow.
6. Add 5 ml of starch solution to
each flask, and shake thoroughly;
continue the titration until the blue
color disappears.
Store the standardized sulfite-TCM
solution in a glass-stoppered bottle or
flask.
3.12 Working Sulfite-TCM
Solution
A quantity of 5 ml of the standard
solution (prepared above) should be
pipetted into a 250-ml volumetric
flask, and diluted to the mark with
0.04M absorbing reagent. The SO2
concentration in the working solution
should be calculated by using the data
in Subsection 3.10, as follows:
ug sn./mi = /32.000 (A-B)NT)* n m
\ 25 /
Equation 3-3
where A and B are averages of the
three replicate titrations, and
32,000= milliequivalent weight of
SO2, fjg
A= volume of thiosulfate
needed for the blank, ml
B = volume of thiosulfate for
the sample, ml
NT= normality of thiosulfate
titrant
0.02= dilution factor
25 = vol. of standard sulfite
solution, ml.
This solution is stable for 30 days at
5°C (41 °F) if refrigerated. If not kept
at 5°C, it should be prepared fresh
daily.
3.13 Pararosaniline Stock
Solution
Harleco Co. offers high purity
pararosaniline (PRA) dye that can be
used without purification for the
preparation of the standard curve
(described in Subsection 5.2) if the
slope, the intercept, and wavelength
of maximum absorbance are within
specifications. If the specifications are
not met, the dye must be purified.
3.13.1 Dye Specifications - Dye
specifications are as follows:
1. The dye must have a maximum
absorbance at a wavelength of 540
nm when assayed in a buffered
solution of 0.1 M sodium acetate-
acetic acid.
2. The absorbance of the reagent
blank, which is temperature-sensitive
(0.015 absorbance unit/°C), must not
exceed 0.170 at 22°C with a 1-cm
optical path length when the blank is
prepared according to the specified
procedure.
3. The calibration curve (Subsection
5.2) must have a slope equal to 0.030
±0.002 absorbance unit//ug S02 with
a 1 -cm optical path length when the
dye is pure and the sulfite solution is
properly standardized.
3.13.2 Purification Procedure for
PRA - The following purification
procedure is given in the event that
the PRA does not meet the
specifications.
1. Place 100 ml each of 1-butanol
and 1N HCI in a 250-ml separatory
funnel, shake, and allow to
equilibrate. Note: Certain batches of
1-butanol contain oxidants that create
an SO2 demand. Check before using
by placing 20 ml of 1-butanol and 5
ml of 20 percent Kl in a 50-ml
separatory funnel and shaking
thoroughly. If a yellow color appears
in the alcohol phase, either redistill
the 1 -butanol from the silver oxide
and collect the middle fraction, or
purchase a new supply of 1-butanol.
2. Weigh 100 mg of pararosaniline
hydrochloride in a small beaker; add
to it 50 ml of the equilibrated acid
(drained from the bottom of the
separatory funnel in Step 1); and then
let the mixture of PRA and acid stand
for several minutes.
3. Add to a 125-ml separatory
funnel 50 ml of the equilibrated 1 -
butanol (drawn from the top of the
separatory funnel in Step 1), transfer
to the funnel the acid solution
-------
Jan.1983
Section 2.1.3
containing the dye, and then extract.
The violet impurity will transfer to the
organic phase (top layer).
4. Transfer the lower aqueous
phase from the separatory funnel into
another separatory funnel, add 20 ml
of 1-butanol, and extract again.
Repeat the extraction procedure in
Step 4 with three more 10-ml
portions of 1-butanol This procedure
usually removes most of the violet
impurity that contributes to the blank,
but the extracted phase (bottom) will
still be red.
5. After the final extraction, filter
the acid (bottom) phase through a
cotton plug into a 50-ml volumetric
flask, and dilute to the mark with 1N
HCI. This PRA stock reagent will be
yellowish red
3.13.3 Assay of Pararosaniline
Stock Solution The following assay
should be performed after each
preparation or purchase of a new lot
of PRA.
1. To prepare a buffer stock
solution with a pH of 4.79, dissolve
13.61 g of sodium acetate trihydrate
m distilled water in a 100-ml
volumetric flask, add 5.70 ml of
glacial acetic acid, and dilute to the
mark with water.
2. Dilute 1 ml of the purified PRA
stock solution (Subsection 3.13.2) to
the mark in a 100-ml volumetric flask
with distilled water.
3. Transfer a 5-ml aliquot to a 50-
ml volumetric flask; add 5 ml of the
acetate/acetic acid buffer solution
(from Step 1); and dilute the mixture
to the mark with distilled water. Let
the mixture stand for 1 h.
4. Measure the absorbance at 540
nm with a spectrophotometer.
Compute the percent purity of the
PRA:
%PRA = AK
W Equation 3-4
where
%PRA= PRA purity, %
A= measured absorbance of
the final mixture, absorbance
units.
K= conversion factor value
(molar absorptivity),
dependent on quality of
spectrophotometer and
associated equipment5 (e.g.,
1-cm cuvettes and a spectral
band width half intensity of
<11 nm, K = 21.3);/Vote; If
these specifications are not
met, the dye analysis will be
incorrect;
W= weight of dye in 50 ml of
PRA stock solution, g (e.g., if
100 mg is used to prepare
50 ml in the purification
procedure, W = 0.100 g; and
if 0.5 g is used to prepare
250ml, W is still 0.1 OOg;
when obtained from
commercial sources, use the
stated concentration to
compute W; for 0.20 percent
concentration of 98 percent
purity PRA, W = 0.098 g per
50 ml).
5. Record the results of the assay
in a calibration log.
3.14 Pararosaniline Reagent
The procedure for preparing a
pararosaniline reagent is as follows:
1. To a 250-ml volumetric flask,
add 20 ml of PRA stock solution.
2. Add an additional 0.2 ml of stock
solution for each percentage that the
stock assayed below 100 percent.
3. Add 25 ml of 3M phosphoric
acid. Dilute to the 250-ml mark with
distilled water.
This reagent, stored in a glass-
stoppered bottle, is stable for at least
9 mo.
-------
Section 2.1.3
Jan. 1983
Table3.1 Activity Matrix for Preparation of Reagents
Reagent
Distilled water
Acceptance limits
KMnOt color (pink)
Frequency and method
of measurement
Test only if slope and
Action if
requirements
are not met
Purify the water.
Water storage
Absorbing reagent pH test
Absorber reagent storage
Sulfamic acid
Formaldehyde
Starch indicator solution
Stock iodine solution
Working iodine solution
Hydrochloric acid
Stock sodium thiosulfate
Sodium thiosulfate titrant
Standard sulfite-TCM solution
Working sulfite-TCM solution
Stock pararosaniline solution
PRA reagent
persists after 1 h at room
temperature
Inert container with vent
guard
30
-------
Jan. 1983
Section 2.1.4
4.0 Sampling Procedure
The quality assurance activities for
sampling are presented in Table 4 1 at
the end of this section.
4.1 Selection of Sampling
Train
A suitable sampling probe consists
of a Teflon® or glass tubing and an
inverted funnel of one of these
materials. The funnel is oriented to
preclude the sampling of precipitation
and large particles. The residence
time of the sample in the probe
should be less than 20 seconds (see
Section 7 of 40 CFR Part 58,
Appendix E).
A midget impinger sampling train
(Figure 4.1) is needed for short-term
sampling (<3 h). With this sampling
train, the flow control is maintained
either by a critical flow orifice or by a
needle valve with a rotameter to
indicate the flow rate. For short-term
sampling (30 mm or 1 h), a 30-ml all-
glass midget impinger should be used,
as specified in the Reference Method,
Section 2.1.11 (Figure 4.2). The nozzle
of the impinger should have an inside
diameter of 1.0 mm (0.05 in.), and it
should deliver 2.5 to 3.1 liters/min
(0.09 to 0.11 ftVmin) at 305 mm (12
in.) H2O vacuum.
The sampling train commonly used
for 24-h sampling (Figure 4.3)
consists of polypropylene bubbler
tubes and critical orifices for flow
control. For 24-h sampling, the
absorber selected should consist of:
1. A polypropylene container that is
164 mm (6.5 in.) in depth and 32 mm
5mml.D.-+\
L_ 1 70 mm i
88 mm
I
-I —
r
VI
v_
-«
f ,
...*
•< —
/t M
/ 25 mm
Inside 0. 0.
Clearance
3 to 5 mm
_L_
10 mm O.D.
24/40 Concentric with
Outer Piece and with
Nozzle
Graduations at 5 ml
Intervals. All the
Way Around
-Nozzle I. D. Exactly
1 mm; passes 009 to 0.11
cfm at 12 in, H2O Vacuum
Pieces Should Be Inter-
shangeable. Maintaining
Nozzle Centering and
Clearance to Bottom
Inside Surface
Figure 4.2 Midget Impinger
specifications.
(1.26 in.) in diameter and has a
permanent mark indicating 50 ml
volume. (Available from Bel Art
Products, Pequannock, New Jersey).
2. A two-port polypropylene tube
closure (commercially available).
Rubber stoppers are not acceptable.
3. A glass impinger tube that is 158
mm (6V* in.) in length and 6 mm (0.24
in.) in diameter and has an outlet
orifice diameter that fits a No. 79
jeweler drill. (No. 78 is too large.) The
required orifice size is between 0.368
and 0.406 mm (0.014 and 0.016 in.).
Hypodermic
Needle
' Rubber
Septum
m To Vacuum
Pump
Needle Valve
f—fc*J— -^ T° Vacuum
Pump
Flow Meter
Figure 4.1 Midget impinger sampling train.
Clearance from the bottom of the
absorber to the tip of the stem must
be 6 ±2 mm.
4.2 Preparation of Sampling
Train
4.2.1 Cleaning the Absorber -
Before each use, the following
procedure should be used for cleaning
each absorber.
1. Wash in hot water.
2. Wash 1 h in an acid bath (1 part
HN03, 2 parts HCI, 4 parts distilled
H20).
3. Rinse with distilled water.
4. Air dry (drain).
4.2.2 Dispensing the TCM - The
quantity of TCM absorbing reagent
needed for the desired sampling
period is transferred to the absorber
as follows:
1. Transfer of 50 ml of TCM with
an automatic reagent dispenser is
acceptable for 24-h periods.
2. Transfer of 10 ml of TCM is
required for 30-min and 1-h periods.
Warning: TCM is highly poisonous.
Wear rubber gloves when dispensing
TCM. If spilled on the skin, flush with
water immediately. Ship the TCM in
test tubes with screw caps (Figure
4.4) that have Teflon or equivalent
inner seals.
4.2.3 Assembly of Absorber - The
absorber is assembled as follows:
1. After inspecting the impinger tip
for damage during shipment and
replacing if necessary, place the
impinger stem in the outer sleeve of
the all-glass unit for 30-min and 1-h
sampling. Seal by placing a thin film
of silicone stopcock grease around the
ground-glass joint.
2. Assemble the absorber as shown
in Figure 4.5 for 24-h sampling.
4.2.4 Identifying the Sampling
Apparatus - A stick-on label should be
used to mark the following
information on each absorber.
1. Date of preparation
2. Sampling site number
3. Date to be used
Record the absorber and the orifice
identifications in the laboratory log
book.
4.2.5 Packing for Shipment to the
Field - The absorber should be packed
either in a wooden block container
that has been predrilled for absorber
-------
Section 2.1.4
Jan. 1983
Glass Inlet Manifold
Caps on
Unused Nipples
J
Glass or Teflon
Sampling Line
Caps on Unused Nipples
Brass Vacuum
Manifold
<=» Outlet
Vacuum \ \* Muffler
auge
Funnel
Polypropylene
Tube
Absorber for
24h sampling
Trap
Note. A Midget Impinger is
Used for 1 -hour sampling.
Figure 4.3 Twenty-four-hour sampling train.
' Screw Top
To Sample Inlet
Manifold
To Vacuum
System
•^-Polypropylene Tube
Etched 50 ml Mark
Absorbing Reagent
50 ml (TCM)
Screw Top
Polypropylene
2-Port
Closure
Glass
Impinger
Polypropylene
Tube —
Etched 50-ml
Mark
Absorbing
Reagent
(TCM)
Figure 4.4
Screw-top bubbler for
shipment
Figure 4.5
Absorber for 24-hour
sampling
flasks according to the EPA-NASN
design, or in a light-weight shipping
container that has an "Etha foam"
insert designed with appropriately
sized holes to support the bubbler
tubes. This insert can be used in a
heavy-duty fiberboard container for
shipment to the field, and it will
reduce the shipping costs by a factor
of approximately 5. Caution: Collected
SO2 samples must be shipped and
stored at <5°C (<41 °F); therefore, the
packing process described may be
suitable for shipping absorber tubes to
the field, but not for returning the
collected SC>2 samples (unless ice
packs are used).
4.2.6 Connecting the 24-h Samp/ing
System Components - The sampler
components shown in Figure 4.6
should be assembled as follows:
1. Attach the sample inlet line
consisting of the Teflon® or glass
tubing and the funnel, as shown.
2. Extend the funnel-and-sample
inlet line out-of-doors through a
window or other opening to avoid
obstructions to air flow near the inlet.
See Section 2.0.2 for siting
guidelines.
3. Support and secure the tube and
funnel in their positions so that they
will not come loose during sampling.
(The funnel should be hung down so
that rain will not be drawn into the
sampler)
4 Use a temperature-controlled
shelter. The temperature of the
absorbing solution must be
maintained at 15° ±10°C during
sampling. As soon as possible
following sampling and until analysis,
the temperature of the collected
sample must be maintained at 5°
±5°C Where an extended period of
time may elapse before the collected
sample can be moved to the lower
storage temperature, a collection
temperature near the lower limit of
the 15 ±10°C range should be used
to minimize losses during this period.
Thermoelectric coolers specifically
designed for this temperature control
are available commercially and
normally operate in the range of 5° to
15°C. Small refrigerators can be
modified to provide the required
temperature control; however, inlet
lines must be insulated from the
lower temperatures to prevent
condensation when sampling under
humid conditions. A small heating pad
may be necessary when sampling at
low temperatures (<7°C) to prevent
the absorbing solution from freezing.
The thermostat in the shelter should
be checked to ensure that it is
operating properly. The absorbing
solution must be shielded from light
during and after sampling. Most
commercially available sampler trains
are enclosed in a light-proof box.
5. Use vacuum-type tubing to
connect the metal vacuum manifold to
the intake of the vacuum pump; place
a pinch clamp on this section of
tubing (as shown in Figure 4.6), but
do not tighten it; and be sure all
connections are airtight, but without
constrictions in the tubing.
6. Electrically connect the vacuum
pump to the timer switch (Figure 4.6);
connect the timer to a 24-h 110-VAC
outlet, and connect the sampler box to
a 24-h outlet. A timer is
recommended to initiate and stop
sampling for the 24-hour period. The
timer is not a required piece of
equipment; however, without the
timer a technician would be required
to start and stop the sampling
manually. An elapsed-time meter is
-------
Jan. 1983
Section 2.1.4
Sample Inlet Line
and Funnel
Tubing to Connect
Exhaust Manifold
to Vacuum Pump
Sampling
Tram
Vacuum Pump
Figure 4.6 Diagram of an SO2 sampling apparatus.
also recommended to determine the
duration of the sampling period.
4.2.7 Installing the Critical Orifice -
Tubing for the absorber and the
sampling apparatus should be color-
coded to facilitate proper positioning
of absorbers and correct connections
for tubes (Figure 4.7). Accordion-type
tubing is used to connect the glass
intake manifold to the impinger tube
of the absorber; smooth tubing is used
for all other connections. A step-by-
step installation procedure for the 24-
h bubbler is presented here.
3. Transfer the caps from the
reagent-filled absorber to the used
absorber. Note: Always install the
tube cap or the tubing on the
impinger tube (color-coded side of
absorber) first and remove it last;
otherwise, some of the absorbing
reagent/sample may be forced out of
the impinger opening and lost.
4. Gently but firmly insert the
accordion inlet tube from the glass
manifold onto the color-coded tube
(impinger tube) of the absorber lid,
and be sure that the fit is airtight.
5. Gently but firmly insert the
smooth tubing from the trap to the
unpamted outlet tube of the absorber.
6. If the hypodermic needle is to be
replaced, insert the new needle into
the center of the rubber septum
attached to the membrane filter unit
(Figure 4.8). The needle must be put
in straight. If the needle is accidently
bent, it should be destroyed and
discarded, and another needle should
be used
7. Slide the base of the needle onto
the metal vacuum manifold (Figure
4.9) Manipulate the needle and/or
rotate the trap, if necessary, to obtain
a tight connection
8 Leak-check the total system by
activating the vacuum pump, capping
off the plastic sample inlet nipple,
and visually checking for bubbling
Should a leak be detected, check all
fittings for leaks. Heat-shrink material
(as shown in Figure 4.3) can be used
to retain the cap seals if there is any
chance of the caps coming loose
during sampling, shipment, or storage.
(Also see Subsection 4.3.1.)
9. Shield the absorber from
sunlight during and after sampling if
the sampling train is not housed in a
closed box. One means of
accomplishing this is to wrap the
absorber in aluminum foil.
10. Recheck the arrangement,
alignment, and tightness of all
connections, and verify the following
points:
a. The accordion tubing from the
glass manifold goes to the color-coded
side of the absorber lid.
b. The needle is not bent or
obstructed.
c. The needle fits the exhaust
manifold tightly.
d. The inlet filter and tubing are
connected tightly.
e. The vacuum pump connections
are tight
4.3 Collection of the
Sample
Operation of the sampling
apparatus is started and stopped by
the timer. Ranges of sample air flow
rates to be used for different sampling
periods are as follows
1. Remove the used absorber from
he sampling train by gently but firmly
'pulling the inlet and the outlet tubing
from the absorber.
2. Exchange the reagent-filled
absorber for the used absorber.
Sampling period, h
Flow rate, cmVmm
Hypodermic needle
size and gauge
1/2
1 to 3
24
900 to 1100
450 to 550
180 to 220
1 in., 22 gauge
5/8 in., 23 gauge
3/8 in., 27 gauge
-------
Section 2.1.4
Jan. 1983
Figure 4.7. Closeup view of absorber installation.
Figure 4.8. Installation of the critical orifice in the sampling train.
4.3.1 Operational Check -
Procedural steps described in this
subsection are performed by the
operator prior to the actual collection
of the sample. These operational
checks can be performed any time
before the sampling. Normally, they
are performed immediately after the
prior sample is removed.
1. If a rotameter equipped with a
needle valve is used, adjust the
system flow rate to the prescribed
value on the sample record form
(Figure 4.10). The manufacturer's
calibration chart may be used to
obtain this approximate setting.
Proceed to step No. 7 below.
2. If a critical orifice is used,
completely close the pinch clamp
between the sampler and the vacuum
pump or kink the tubing between the
orifice and the vacuum pump.
3. Turn the vacuum pump on, and
record the vacuum reading ("Start-
Clamps," Figure 4.10).
4 If the vacuum gauge reading is
below 530 mm (21 in.) Hg, make sure
the pinch clamp (or kink) is closed and
the tubing is securely connected to
the pump inlet.
5. If the vacuum reading remains
below the reference value (Step 4),
repair or replace the pump.
6. Turn the vacuum pump off.
7. Open the pinch clamp (if
necessary). Record the reading of the
elapsed-time meter unless a bubble
meter is used to measure the flow. If
a bubble meter is to be used, record
elapsed time after the initial flow
measurement.
8. Leak-check and measure the
initial flow rate at the inlet to the
absorber by using one of the
procedures in Subsection 4.4.
9. Turn on the vacuum pump and
record the vacuum gauge reading on
the sample record form in the space
marked "Start-Open."
10. Gently lift the sampling train
halfway out of the sampler box, and
check to be sure the absorber is
bubbling. If not, check for loose
connections or a plugged line.
11. Turn the timer off, and set it for
the sampling period.
12. Record the date and time on
the sample record form.
4.3.2 Postsampling Check - Steps
listed in this subsection are performed
by the operator after the sample
collection.
1. For apparatus with a rotameter:
a. Measure the final flow rate,
using the same procedure as that
used for the initial flow rate, and
record on the sample record form.
b. Turn the timer switch off.
c. Record the elapsed-time meter
reading.
2. For apparatus with a critical
orifice:
a. Leak-check and measure the
final flow rate, using the same
procedure as that used for the initial
flow rate, and record on sample
record.
b. Record the vacuum gauge
reading on the sample record form (in
the space marked "End-Open") and
record the elapsed-time meter
reading.
-------
Jan. 1983
Section 2.1.4
Figure 4.9. Connecting the critical ofifice to the exhaust manifold
c. Close the pinch clamp tightly.
d. Record the vacuum gauge
reading on the sample record form in
the space marked "End-Clamp."
e. Turn the time switch off
3 Check the condition of the
membrane filter, and replace the filter
if it is discolored or cracked The
porosity of the filter should be 0 8 to 2
fjm. It is used to protect the flow
controller from particles during long-
term sampling. This item is optional
for short-term sampling Check the
moisture trap and replace the silica
gel if more than three-fourths of the
indicator is pink Glass wool may be
substituted for silica gel during the
collection of short-term samples (1
hour or less), or for long-term (24-
hour) samples if flow changes are not
routinely encountered
4. If the ambient temperature is
lower than the thermostat setting in
the sampling box, check to be sure
that the thermostat and the heater are
functioning.
5. Record the average temperature
of the absorbing solution for the
sampling period For 30-mm and 1-h
samples, the temperature immediately
before, after, or at any time during the
sampling period is adequate. For 24-h
samples, a recording thermometer is
recommended for use within the
sampling tram shelter, record the
mean of the readings from the
recording thermometer kept in the
sampling box. A minimum-maximum
thermometer has also been used for
this purpose, but it only provides an
indication of the degree of
temperature control within the
sampling box; if the minimum-
maximum thermometer readings are
unavailable, record the normal
thermostatic setting of the sampling
box or the ambient temperature for
the sampling period, whichever is
greater. Note' Unfortunately, the SO2-
TCM complex is thermally unstable. The
SO2 concentration measured in an air
sample depends greatly on the
temperature of the TCM absorbing
solution during sampling and after
sample collection. That is, the SO2 is
lost from the collected samples at
rates that are highly dependent on
temperature and that are independent
of concentration as long as EDTA is
used as called for, as shown by the
following6-
Temperature,
°C °F
20
30
40
50
68
86
104
122
Rate of S02 loss,
%/day
0.9
5.0
25.0
73.6
The temperature of the absorbing
solution during sampling must be
maintained between 5° and 25°C.
During storage and transport, the
temperature must be maintained at 5°
±5°C
6 Record the barometric pressure
for the sampling period (obtained with
a calibrated instrument or from the
local weather bureau)
7. Check the absorber for any
reagent loss due to evaporation Mark
the level of the solution with a piece
of tape or a grease pencil. Record an
estimate of the quantity of absorbing
reagent on the sample record form or
state under "Remarks" that there was
no evaporation
4.3.3 Samp/ing Time Period - The
sampling time period should be
recorded on the sample record form.
For 24-h samples, the sample must
be voided if the sampling period is
<23 h or >25 h. The actual sampling
period must be known to within ±15
mm (see Section 2.1 2)
4.3.4 Sample Handling - The
procedure for sample handling is as
follows:
1. First remove the accordion
tubing (color-coded) from the absorber
impmger tube.
2. For 24-h samples, estimate the
volume of absorber reagent remaining
in the absorber flask after sampling,
mark the TCM level in the absorber
with tape or some other easily
removable indicator, and record the
estimate on the sample record form.
To assist in this estimation, mark the
tubes at the 35- and 50-ml levels with
a marking pen. If <35 ml of sampling
reagent remains after sampling, void
the sample, and indicate this on the
form. If 50 ml of sampling reagent
remains after sampling, state (under
"Remarks" on the sample record
form) that no evaporation occurred
during the sampling.
3. If there is evidence of
malfunction (e g , absorbing reagent
forced out of absorber into the
vacuum system), record this on the
sample record form Normally, the
sample is invalid under this
circumstance
4. Place the tube caps first on the
impmger tube (color coded) of the
absorber and then on the suction
tube Press caps firmly in place, and
place the absorber in the shipping
block. Note: For 30-mm and 1 -h
samples collected in glass impmgers,
shake the absorber thoroughly,
quantitatively transfer all of the
exposed reagent to a test tube or
small bottle with a Teflon-lined
threaded cap, and place the sample in
the shipping block
5 Record on the sample record
form any pertinent observations
relative to sources, weather
-------
Section 2.1.4
Jan. 1983
Station Location
City & State
Site & Address
Protect
Site No
12-
Gas Bubbler Data Record
Open Clamp
Vacuum Reading Start A-jjJ
Vacuum Reading End
Start Samp/ing
mo
Stop Samp/ing &
Pollutant
Sampler ID No. —
Type of Flow Measuring Device —
Identification Number of Device
Initial Flow *Q*f ml/Hll/]
. Sample No.
Elapsed Time Start
Elapsed Time Stop
Nominal Flow Rate
?£0_
Final Flow
204
% Difference
A0_
202.
2.05
Average
Average sample temperature
Ambient temperature: Start _
Barometric pressure. Start —
REMARKS
"7.0
Average
205 *.//
°C Relative humidity
. °C. Stop °C. Average^
nm Hg, Stop mm Hg. Averagel-HUmm Hg
Meteorological conditions (or use when anomaly occurs
WIND calm \s light gusty
VISIBILITY r clear hazy
SKY * clear scattered overcast
HUMIDITY dry —^L. moderate humid rainy
TEMP °F <20 20-40 41 -60 ^ fit -80 _
Sample collected within
guidelines given below
.>80
Guidelines
Proper flow rate — 1/2-h samples - 900-1100 cm3/mm
1 -h samples - 450-550 cm3/min
24-h samples - 180-220 cm3/mm
24-h sampling — 23 h < sampling time < 25 h
— >35 ml of absorbing reagent remain after samp/ing
— sampler timer accuracy ±15 min/24 h
Figure4. JO. Sample record form.
conditions, etc., that might affect the
SO2 level.
6. Complete the sample record form
in duplicate, return the original copy
with the absorber in the shipping
block, and file the duplicate in the site
log book.
7. If samples must be stored before
shipment for analysis, store them in a
refrigerator or cooler at 5°C (41 °F). A
shipping container that can maintain
a temperature of 5° ±5°C is used to
transport the sample from the
collection site to the analytical
laboratory. Ice coolers or refrigerated
shipping containers have been found
to be satisfactory. The use of eutectic
cold packs instead of ice will provide a
better temperature control. Such
equipment is commercially available
from Cole-Parmer Company, 7425
North Oak Park Avenue, Chicago,
Illinois 60648.
4.4 Determination of the
Flow Rate of SCh Sampling
Trains
The SOz sampling train that is used
for short-term periods of 30 minutes
and 1 hour normally has one of two
flow control systems. One system has
a needle valve and indicates the flow
rate with a rotameter. The other uses
various sizes of stainless steel
hypodermic needles to control the
flow. The 24-h sampling trains also
use stainless steel hypodermic
needles to control the flow. For short-
term samples, the standard flow rate
is determined at the sampling site at
the initiation and completion of
sample collection by use of a
calibrated flow-measuring device
connected to the inlet of the absorber.
For 24-hour samples, the standard
flow rate is determined at the time
the absorber is placed in the sampling
train and again when the absorber is
-------
Jan. 1983
Section 2.1.4
removed from the train for shipment
to the analytical laboratory. A
calibrated flow-measuring device
connected to the inlet of the sampling
train is used for this purpose. The
flow rate determination must be made
with all components of the sampling
system in operation (e.g., the
absorber temperature controller and
any sample box heaters must be
operating).
4.4.1 Flow Rate Measurement -
Three step-by-step procedures for
measuring the sampling flow rates
are presented here. They involve the
use of a mass-flow meter, a
rotameter, or a soap-bubble meter.
The reference method requires that
the flow rate of each S02 sampling
train be measured before and after
each sampling period. The initial and
final flow rates must agree within ±5
percent or the sample is voided.
Therefore, it is very important that the
flow-measuring device selected have
the appropriate range, accuracy, and
readability to meet this specification.
The typical flow rates for 30-min, 1-
hour, and 24-hour samples are 1000,
500, and 200 ml/min, respectively.
The range of a mass-flow meter
sed as a flow measuring device
hould be such that the measured
flow is between 50 and 90 percent of
full scale Regardless of the range,
the mass-flow meter must have a
readability and reproducibility of 1
percent of the measured flow to
ensure that only samples from trains
whose flow rate did change by more
than 5 percent are invalidated. Mass-
flow meters should be calibrated
according to procedures given in
Subsection 2.1.3.
Rotameters used as flow measuring
devices should have a minimum scale
of 6-in. (150 mm) with no less than
100 divisions The measured flow
should be between 50 and 90 percent
of full scale. If these conditions are
met, only samples from the trains
whose flow rate did change by more
than 5 percent should be invalidated.
Rotameters should be calibrated
according to procedures presented in
Subsection 2.1.4.
Bubble meters should be of a size
that the volume is displaced in 10 to
30 seconds during the flow
measurement. Bubble meters are
calibrated according to procedures
presented in Subsection 2 1.2
When flow measurements are made
iy inserting a mass-flow meter or
rotameter between the probe and the
absorber, the time required for the
initial and final flow measurements
should be included in the total
sampling time.
Bubble meters are not as easily
inserted between the probe and
absorber inlet, and the solution in the
bubble meter will absorb at least
some of the SOa. Therefore, the time
required to do the initial and final flow
measurements should not be included
in the sampling time, and a charcoal
scrubber should be Inserted between
the bubble meter and the absorber to
ensure the removal of SOz. Care must
be exercised in the selection of the
charcoal tube so that the pressure
drop across the sampling system will
not be increased enough to alter the
sampling rate.
4.4.2 With a Mass Flow Meter - The
following procedure should be used to
measure the flow before and after
sampling.
1. Assemble the equipment for
sampling, as shown in Figure 4.11.
2. Be sure all connections are tight.
3. Be sure the absorber inlet line is
connected to the mass-flow meter
transducer outlet.
4. Zero the mass-flow meter.
5. Turn the vacuum pump on and
adjust the needle valve to obtain
approximately the desired flow (prior
to sampling only). Record the vacuum
reading on the sheet.
6. Check for bubbles in the
sampling tube. Plug the inlet of the
mass-flow meter, and check for zero
flow on the rotameters. If a zero flow
is not obtained, check for leaks.
Unplug the inlet.
7. Read the flow rate on the mass-
flow meter after the meter indicator
has stabilized (about 30 s) and shut
off the pump.
8. Turn the pump on, and repeat
Step 7 two more times.
9. Average the three flow rates.
4.4.3 With a Rotameter - The
following procedure should be used to
measure the flow before and after
sampling.
1. Assemble the equipment, as
shown in Figure 4.12.
2. Place a new rubber septum on
the tube (prior to sampling only).
3. Be sure all connections are
tight.
4. Be sure the line from the surge
tank outlet is connected to the inlet of
the sampling tube absorber.
5 Turn the vacuum pump on, and
check the vacuum by placing a finger
over the end of the vacuum line. (The
vacuum gauge should read at least
530 mm (21 in.) Hg at a barometric
pressure of 760 mm (29.92 in.). Turn
the vacuum pump off.
6. Insert a needle through the
center of the septum, perpendicular to
the plane of the septum face.
7. Turn the vacuum pump on. Slide
the needle holder snugly into the
recess at the base of the needle, and
check for bubbles in the sampling
tube. Plug the inlet to the rotameter
and check to see that bubbling ceases
in the absorber. If bubbling persists,
check for leaks. Unplug the inlet.
8. Read the ball position on the
rotameter; record the flow rate
corrected to STP, 760 mm (29.92 in.)
Hg and 25°C (77°F), from the
rotameter calibration curve; and read
the vacuum gauge to make sure the
vacuum is sufficient during the flow
measurement.
9. Repeat Step 8 two more times.
Turn pump off and then back on after
each run.
1 0. Record the ambient temperature
and pressure or obtain the average for
the sampling period from the local
weather bureau.
1 1 . Average the flow rates of the
three runs4
1 2. If the rotameter is used in a
field location where the barometric
pressure and/or temperature is
different from the conditions under
which the rotameter was calibrated,
apply the following corrections to
convert the flow rate to standard
conditions. This correction factor is
not advisable for conditions that differ
greatly from those at which the
rotameter was calibrated. Greater
accuracy can be obtained by
developing calibration curves for
expected conditions.
\760 Ti /
Equation 4-1
where
Qs = flow rate corrected to standard
conditions from field conditions,
ml/min
Qt= flow rate at field conditions
from calibration curve, ml/min
Pf= barometric pressure at field
conditions, mm Hg
Tf= temperature at field conditions,
4.4.4 With a Bubble Meter - The
following procedure should be used to
measure the flow before and after the
sampling.
1. Assemble the equipment for
sampling, as shown in Figure 4.13.
2. Place a new rubber septum on
the sampling tube only prior to
sampling.
3. Be sure all connect' * -re tight.
-------
Section 2.1.4
Jan. 1983
Note: Rotameter and needle valve can
be replaced with appropriately sized
hypodermic needle (Section 2.1.11).
To Probe
In
Out
Mass-Flow meter
Needle
Valve
— \ Rotameter
To Vacuum Pump
Glass wool or
Silica Gel
Trap
Impinger
Figure 4.11 Determination of flow rate of short-term sampling train using a mass-flow meter.
Rotameter
To Probe
Surge Tank
(Voiume-
0.25-0.5 L)
Teflon or
Glass
- D> — »
To Sample Probe
Glass
Impinger 1 •
Stem
propylene Tube — *
\
1
t*
t
^
i
&
\
Polypropylene
- 2-Port Tube Closure
Absorber for
24 h Sampling
Trap
Note A midget impmger is
used for 1 -hour sampling.
Figure 4.12 Determination of flow rate of long-term sampling train using a rotometer.
4. Be sure the charcoal tube is
connected between the bubble meter
and the inlet of the sampling tube
impinger.
5. Turn the vacuum pump on and
check the vacuum by placing a finger
over the end of the vacuum line. (The
vacuum gauge should read at least
530 mm (21 in.) Hg at a barometric
pressure of 760 mm (29.92 in.) Hg.
Turn the pump off.
6. Insert a needle through the
center of the septum, perpendicular to
the plane of the septum face.
7. Turn the vacuum pump on.
8. Slide the needle holder snugly
into the recess at the base of the
needle, and check for bubbles in the
sampling tube. Plug the inlet to the
bubble meter and check to see that
bubbling ceases in the absorber. If
bubbling persists, check for leaks.
Unplug the inlet.
9. Touch the surface of the soap
solution with the open end of the
bubble meter so that a soap bubble
will start to travel up the bubble meter
tube. Repeat several times or until the
bubble travels the full length of tube
without breaking.
10. Touch the surface of the soap
solution with the open end of bubble
meter so that a single bubble starts to
travel up the bubble tube. When the
bubble passes the first line of the
graduated scale, start the stopwatch
arid record the time and volume
displaced. Read the vacuum gauge to
make sure the vacuum is sufficient
during flow measurement.
11. Repeat Step 10 two more
times. Record the time and the
volume each time.
12. Record the ambient
temperature and pressure, or obtain
the average for the sampling period
from the local weather bureau.
13. Average the times and volume
displacements for the three runs.
14. Divide the average volume
displacement by the average time to
determine the flow rate.
-------
Jan. 1983
Section 2.1.4
6-in. Tube
6-10 Mesh
Activated
Charcoal
Bubble
Meter
WO ml
Polypropylene
, 2-Port Tube Closure
To Sample Probe
1 Membrane Filter
J
Glass
Impinger-
Stem
Polypropylene Tube-
Hypodermic Needle
0 ml
Beaker with
Soap Solution
Vacuum
Gauge
Absorber for
24h Sampling
Trap
\Stopwatch
Figure 4.13 Determination of flow rate of long-term sampling train using soap-bubble meter
15. Correct the average flow rate to
standard conditions of 760 mm (29.92
in.) Hg and 25°C (77°F), using
Equation 4-2.
Q5t
-------
Section 2.1.4
10
Jan. 1983
Table4.1 Activity Matrix for Sampling Procedure
Activity
Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
Absorber selection
Cleaning absorber
Dispensing TCM
Assembly of absorber
Determination of flow rates
before and after sampling
Sample ID
Packing for shipment
Sampler assembly. 24-h
bubbler
Installation of absorber and
critical orifice
Collection of sample
Storage of sample before
analysis
/; Short-term, <3 h;
30-ml all-glass midget
impinger
2) 24-h sample; poly-
propylene tube and
closure with glass
impinger tube
31 Orifice ID >#79 drill
and <#78 drill
Clean absorber
1) Short-term period, 10
ml TCM
2) 24-h period. 50 ml TCM
As diagrammed
Percent difference <5%
All required information
Shipped in insulated coo/-
pack container
NASN specifications (Figs
4.6. 4.7. 4.8)
See Subsec. 4.2.6 and
4.2.7.
Air flow rate ±5% (Subsec.
4.3); absorbing solution at
15 ±10°C during sampling
and prior to recovery
Store at 5° ±5°C
Visually check each
sample.
Water and acid bath prior
to each use
Visually check each
sample.
Visually check.
Calibrated flow measuring
device (Sec. 2.1.2).
Visually check.
As above
As above
As above
Initial and Final (Subsection
4.4). Check thermometer
for each sample, Subsec.
4.3.2.
As above
Select proper absorber
Clean it.
Correct the discrepancy
Reassemble.
Void sample.
Complete the stick-on
label/
Repack as appropriate.
Reassemble if necessary.
Reassemble and/or select
proper orifice.
Void sample.
Void sample.
Void sample.
-------
Jan. 1983
Section 2.1.5
5.0 Analysis of Samples
The quality control functions for
analysis of samples are summarized
in Table 5 2 at the end of this section
5.1 Verification of Field
Record Form
Procedures for verifying the field
record are as follows:
1. Examine the sample record form,
and invalidate the sample if vital
information is missing and cannot be
obtained from field personnel Remove
the samples from the shipping
container. If the shipping period
exceeded 12 hours, verify that the
sample temperature is below 10°C. If
the temperature is above 10°C,
invalidate the sample. Check to see
that the initial and final flow rates
meet the ±5 percent criterion (see
Subsection 4.5.2). Invalidate the
sample if the flow rates differ by more
than 5 percent. If the flow rates differ
by less than 5 percent, the average
value will be used to determine the
S02 concentration. Calculate the
sample volume, using Equation 5-1
Vs,d =
Equation 5-1
where
Vstd= sampling volume, std liters
Q,= standard flow rate determined
at the initiation of sampling, std
liters/mm
Qt^ standard flow rate determined
at the completion of sampling,
std liters/min
t= total sampling time, min.
2. Log the sample into the sample-
receiving log book.
3. Verify the volume marked on the
absorber and recorded on the sample
record form against the sample
volume received. If the volume
received is more than 10 ml for long-
term sampling (2 ml for short-term
sampling) lower than the volume
marked on the absorber, significant
leakage has occurred. Void the
sample. If valid samples have <50 ml
of absorbing reagent, add distilled
water to bring the volume to 50 ml
and continue with the analysis. If
samples have a volume of >50 ml,
measure the volume with a graduated
cylinder (Class A) and record the
volume. Continue with the analysis.
Valid short-term samples are ready for
analysis. If samples are to be stored
before analysis, place them in a
refrigerator at 5°C
5.2 Colorimetric Analyses
The following step-by-step
procedure should be used to obtain
the calibration curve for the
spectrophotometer and to show the
relationship of the /jg of S02 to the
absorbance. Calibration Option 1 of
the reference method is discussed.
The procedure described is intended
to be used with matched
spectrophotometer cells. If an
unmatched pair of cells is used, the
correction listed in the reference
method (Subsection 2..1.11) must be
applied.
1 Prepare a dilute working sulfite-
TCM solution by diluting 10 ml of the
sulfite-TCM solution to 100 ml with
TCM absorbing reagent.
2 Accurately pipette the indicated
volumes (Table 5.1) of the sulfite-TCM
solutions into six 25-ml volumetric
flasks.
3. Add the indicated volumes of
TCM absorbing reagent to bring the
volume in each flask to 10 ml.
4. Add 1 ml of 0.6% sulfamic acid
to each, and allow to stand 10 min.
5. Accurately pipet 2 ml of 0.2%
formaldehyde to each.
6. Add 5 ml of PRA solution to
each, and start the timer.
7. Add recently boiled and cooled
distilled water to bring each flask to
the 25-ml mark. Mix thoroughly.
8. Place all six flasks in a water
bath for at least 30 min, but no longer
than 60 min, at 20°±0.2°C
(68°±0.4°F).
9. Allow at least 5 min for the
spectrophotometer to warm up; adjust
the zero control to bring the meter
needle to infinity absorbance on the
scale; standardize the light control by
Table 5.1
inserting a 1-cm cuvette filled with
distilled water into the sample holder
and adjusting the light control until
the meter reads zero absorbance.
Note: The wavelength scale should be
checked with a standard wavelength
filter traceable to the National Bureau
of Standards initially and after each
160 hours of normal use or every 6
months, whichever occurs first. Use
commerically available, optically
matched 1 -cm cuvettes.
10. Remove the six samples from
the water bath, pour a portion of each
(one at a time) into a cuvette,
immediately read the absorbance at
548 nm, and record on the S02
Calibration Data Sheet (Figure 5.1).
Compute the fjg S02/flask, using the
following equation:
fjg S02 = VTCM/SOZ x CTCM/SOZ x D
Equation 5-2
where
VTcM/so2= volume of sulfite-TCM
solution used, ml
CTCM/SC^ concentration of sulfur
dioxide in the working
sulfite-TCM, fjg SO2/ml
(from Equation 3-3)
D= dilution factor (D = 1 for
the working sulfite-TCM
solution; D = 0.1 for the
diluted working sulfite-TCM
solution).
11. Plot the absorbance (y-axis) and
the fjg of S02 (x-axis) contained in
each 25-ml flask (Figure 5.2).
12. Use regression analysis to
determine the slope, intercept, and
correlation coefficient of the
calibration curve. (Refer to Appendix J
of Volume I of the Handbook7 for
discussion of linear regression
analysis.) See Figure 5.3 for
calculation of the linear regression
parameters.
Sulfite-TCM
solution
Dilute working
Dilute working
Working
Working
Working.
Volume of
Sulfite-TCM
solution, ml
0.0
5.0
10.0
2.0
3.0
4.0
Volume of
TCM, ml
10.0
5.0
0.0
8.0
7.0
6.0
Approximate
total"
ua S02
0.0
3.6
7.2
14.4
21.6
28.8
"Based on working sulfite-TCM solution concentration of 7.20 ug SOz/ml; the
actual total/jg S02 must be calculated by use of Equation 5-2 (shown in Step 10).
-------
Section 2.1.5
Jan. 1983
Date
3-27-81
S02 Calibration Data Sheet
Analyst
Instrument ID
. /so
Color Development Time .
Wavelength _
P(O /
. mm , Temperature *-^' '
nm fjg SO*/ ml (Working sulfite-TCM solution)
7 -2. 0
VTCM so2
0
5
10
2
3
4
D
1
0 1
0.1
1
1
1
fjgSO!
0.0
3.(o
72
Af.f
21. (o
28. Q
Absorbance
0.16,0
0.22&
0.1-7$
0-530
0.6H
1 .024
ug SOs = I/TCM so2 x CTCM so2 x D
I/TCMSO = volume of sulfite-TCM solution used, ml,
CTCM so2 = concentration of SOi in the working sulfite- TCM solution, ug SOi/ml; and
D = dilution factor
Regression analysis results.
Measured
s/OPe 0.03005
0.1575
Intercept
Correlation coefficient
031118
Criteria
0 030±0.002 absorbance units/ug SO2
<0 170 at 22°C (add 0.015 per °C above 22°C)
X3.998
Calibration factor Bs = slope - &.O ug SOz/absorbance unit
Figure 5.1 SOi spectrophotometer calibration data.
13. Check each new calibration
curve for conformance with these
criteria:
a. Slope is 0.03±0 002 absorbance
umts/Aig SC"2. If not, repeat the
calibration. If still outside the limits,
restandardize the sulfite solution and
check the dye.
b. The intercept is <0.17
absorbance units at 22°C (72°F) with
a 1-cm optical path length, and the
blank is ± 0 030 absorbance units of
the regression intercept. If not, check
the temperature of the water bath. If
the new intercept still is outside the
limits, check the chemicals from
which the reagents were prepared
and prepare new reagents
c. The correlation coefficient is
greater than 0.998
14. File the calculations and the
calibration curve in the calibration log
book.
15 Determine the calibration
factor, Bs (/jg SC>2/absorbance units),
which is the reciprocal of the slope.
5.3 Sample Analysis (24-h
Sampling)
The following step-by-step
procedure is to be used for analysis of
field samples.
1. If no leakage occurred during
sample shipment (as indicated by
comparing the volume marked on the
data form after sampling with the
volume received), dilute the sample
with distilled water to 50 ml If the
volume is greater than 50 ml,
measure the volume with a Class A
graduated cylinder and record the
volume.
2. If leakage occurred, invalidate
the sample.
3. Pipette 10.0 ml of the sample
into a 25-ml volumetric flask. Note:
For shorter sampling periods (e g., 1
or 3 h), quantitatively transfer the
entire 10 ml sample to increase the
detection limit.
4 Delay the analysis for 20 mm to
allow any ozone to decompose.
5. Prepare a reagent blank by
pipetting 10.0 ml of absorbing reagent
into a 25-ml volumetric flask for use
throughout the analytical procedure.
Prepare two internal control standards
containing approximately 5 and 15 /jg
of S02 and add absorbing reagent to
bring the volume to 10 ml in 25-ml
volumetric flasks.
6. Analyze the reagent blank and
internal control standards before
the first sample, after every
subsequent 10th sample, and after
the last sample. Each reagent blank
absorbance should be within ±0.03
absorbance units of zero, and the
measured value of each internal
control standard must be within ± 1
/jg of the true value
7 To each 25-ml flask add the
following'
a. 1.0 ml of 0.6 percent sulfamic
acid (allow to react for 10 min to
destroy the nitrate from oxides of
nitrogen).
-------
Jan. 1983
Section 2.1.5
S02 calibration curve
EPA pararosaniline reference method
Analyst Q. ^fmizlls Hate 3-£7'
Calibration Temnerature 2.0.1 C
Calibration factor (Bs) 33. 3
Slope'' = — =33 3 /jg S02/absorbance unit
030
Figure 5.2 Example of S02 calibration curve
b. Pipette 2.0 ml of 0.2 percent
formaldehyde solution.
c. Add 5 0 ml of PRA solution.
8. Start the laboratory timer
previously set for 30 min.
9. Dilute all flasks to 25 ml with
recently boiled and cooled distilled
water, stopper them, and place them
in a water bath at 20°±0.2°C
(68±0.3°F).
10. Set the spectrophotometer
wavelength to 548 nm, and allow at
least 5 min for the spectrophotometer
to warm up. If necessary, adjust the
zero control to bring the meter needle
to infinity on the absorbance scale.
Standardize the light contol by
inserting a cuvette filled with distilled
water into the sample holder and by
adjusting the light control until the
meter reads zero absorbance
11. Determine as quickly and
accurately as possible, the absorbance
of each sample of the internal control
standard and of the reagent blank
Use distilled water, not the reagent
blank, as the reference.
12 Record all absorbance units
from the samples and the internal
control standard on the laboratory
data form. (Figures 5.4a and 5 4b.)
13 If the absorbance of the sample
solution ranges between 1.0 and 2 0,
the sample can be diluted 1:1 with a
portion of the reagent blank and the
absorbance redetermined within 5
minutes Solutions with higher
absorbances can be diluted up to
sixfold with the reagent blank to
obtain scale readings of less than 1.0
absorbance unit It is recommended,
however, that a smaller portion (<10
ml) of the original sample be
reanalyzed (if possible) if the sample
requires a dilution greater than 1:1
14. Dispose of all reagents
containing mercury by using one of
the procedures described in
Subsection 5.5. Until disposal, the
discarded solutions can be stored in
closed glass containers, and they
should be left in a fume hood.
15. Immediately after their use,
clean the cuvettes with isopropanol to
avoid dye deposition on the cuvette
walls
16 Determine the pH of the
samples in step 11 Maximum pH
sensitivity is 1 6 ±0.1 8
17. Calculate the SO2
concentration as follows.
fjg S02/m3 = 103(A-Ao)BsVbxn
VR Va
Equation 5-3
103= conversion of liters to m3
A= sample absorbance
A0= reagent blank absorbance
Bs = calibration factor, /jg
SOa/absorbance unit
VR= the sample air volume
corrected to 25°C (77°F) and
760 mm Hg (29.92 in Hg),
liters,
Va= volume of absorber solution
analyzed, ml
Vb= total volume of solution in
absorber, ml
D= dilution factor (if any) required
to reduce sample absorbance
below 1
And calculate the SC>2 concentration
(ppm):
ppm S02 = //g SOs/m3 x 3.82 x 10 4.
Equation 5-4
18 If the absorbance of the blank is
within ±0.03 absorbance units of the
intercept and if the measured values
of the internal control samples are
within ±0 07 yug/ml SO2 of the actual
value, the analytical values
determined for the field samples can
be accepted as valid. If the reagent
blank and/or the control sample falls
outside the above limits, the reagent
blank, the control sample, and the
calibration curve should be checked
by replication to verify that the above
limits have been met before
reanalyzing the field samples.
5.4 Quality Control Check
of Analysis Procedure
It is recommended that each
laboratory participate in the EPA
national performance audit program
as an independent quality control
check on the analytical method In
this audit program, each participant
receives five samples each 6 mo from
the U.S. EPA Environmental
Monitoring Systems Laboratory. If the
results of these five analyses all fall
within the acceptable range as
published in the EPA survey report,
the analysis procedure is considered
to be in control. Otherwise, the
laboratory should take corrective
action and analyze a second set of
samples to determine if the action
taken has corrected the bias or
imprecision of analytical results.
-------
Section 2.1.5
Jan. 1983
DATA FORM
For Hand Calculations
Calibration
point
number
1
2
3
4
5
6
?,= 7S.6 y
Micrograms
SO2
M
0.0
3.6
7.2
14.4-
21.6
Z8.8
„= .3.229 yW568./
Absorbance
units
(Y!
0./6O
0.266
0.378
0-590
O.QII
1.024
'6 T, --53.134
X2
0
IZ.%
5/.S4-
2C736
^66.56
827.44-
:T,-2.29^37
xy
o
0. 7576
2.7 2 1 &
8.4-960
/Z5/76
29.W2
r
y^
0.025^00
0.070756
0./42884
0.34-8/00
0.65772/
/. 6^^3576
. (number of calibration points]
Equation 1
Calibration Slope, Intercept, and Correlation Coefficient. The method of least squares is used to calculate a calibration equation in the form
of:
y = mx + b
where
y = corrected absorbance,
m = slope, absorbance units/ yg SOa
x = micrograms of SO?.
b= y intercept labsorbance units)
The slope (m), intercept (b), and correlation coefficient fr) are calculated as follows
- (Zx) (ly) = I & ) (51.
.223) -.Q.O3 0050
h -.-
1 1>)-
3.2^
-------
Jan. 1983
Section 2.1.5
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-------
Section 2.1.5
Jan. 1983
Preparation and Calibration
Sample Analysis
Reagent Preparation
reagent water double-distilled
and stored in a borosilicate
glass vessel with vent guard
Absorbing reagent prepared
every 6 mo. clear with 3 0 < pH
<5.0
24-h sampler with polypropylene
tubes and closure with glass
impinger, '/2- and 1 -h sample with
with glass midget impinger
Check of flow-measuring device
against specification.
All data points within +2% of the
best-fit calibration curve for flow-
measuring rotameter
Flow rate measured before and
after each sampling period
Rotameter cleaned and calibrated
every 30 days of operation or
every 6 mo
Sample timer within ±15 min/
24-h. checked every 6 mo
Color/metric analysis blank
within ±0.03 absorbance
calibration intercept, control
sample absorbance within
±1 /jg SO2 of actual value
Calibration curve for ab-
sorbance vs. /jg SOi/m3
slope between 0 03 ±0.002
absorbance units/pg SOz
intercept <0.17, all points
within 0.04 /jg SOz/ml (1 fjg
SOi) of best-fit curve
Reagent
Sulfamic acid, 0.6%
Formaldehyde. 0.2%
Working iodine.
0.1 N
Stock iodine.
0.01N
Sodium thiosulfate,
0.01N
Stock sodium
thiosulfate,
0 1N
Container
Glass stoppered
Glass stoppered
Glass stoppered,
dark
Glass stoppered.
dark
Glass stoppered
Glass stoppered
Frequency
of
Preparation
Before analysis
Before analysis
Before analysis
Yearly
Yearly
Yearly
Working sulfite-TCM solution accurately prepared from standard
solution prior to analysis, stable for 30 days at 5°C (41 °F) if stored in
dark glass-stoppered bottle
Standard sulfite-ICM solution 320-400 ug SOz/ml
Pararosamline (PFtA) reagent 100% assay; stable if stored in dark
glass-stoppered bottle
Assayed PFtA stock solution stored in dark glass-stoppered bottle;
solution prepared if slope of calibration curve deviates
from 0.03 ±0.002
Analytical balance performance within ±0.1 mg of manufacturer's
specifications
Figure 5.4B Laboratory data log (backside)
material to a container and allow it to
dry.
8. The solid material can be sent to
a mercury reclaiming plant. It must
not be discarded.
5.5.2 Method Using A luminum Foil
Strips 1. Put the waste solution in an
uncapped vessel and place it m a
hood.
2. For each liter of waste solution,
add approximately 10 g of aluminum
foil strips. If all the aluminum appears
to be consumed and no gas is
evolved, add an additional 10 g of foil.
Repeat until the foil is no longer
consumed and allow the gas to evolve
for 24 hours.
3. Decant the supernatant liquid
and discard.
4. Transfer to a storage container
the elemental mercury that has
settled to the bottom of the vessel.
5. The mercury can be sent to a
mercury reclaiming plant. It must not
be discarded.
-------
Jan. 1983
Section 2.1.5
Table 5.2 Activity Matrix lor Analysis of Samples
Activity
Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
Verification of field
record form
Flow rate check of system
Calibration of
spectrophotometer
Reagent blank and internal
control standard
All vital information
obtained and verified
Difference in initial and
final flow rates after
sampling <5%
Each calibration curve:
Slope 0.03 ±O.O02 ab-
sorbance un/t/fjg SOz
intercept 0.998
Analysis in accordance
with Subsec. 5.3; absorb-
ance of blank within ±0.03
absorbance units of zero;
measured value of each
internal control standard
within ±1 ug SOz actual
value
Visually inspect after each
sampling period.
Repeat flow rate measure-
ment after sampling.
Check the calibration
curve after samp/ing
Analyze a reagent blank
and internal control
standard before the first
samples, after every sub-
sequent 10th samples and
after the last sample.
Obtain missing data or
invalidate the sample.
Invalidate the sample.
Repeat calibration and/or
standardize the sulfite
solution, and check dye:
check water bath temp.
and/or check chemicals
used to prepare reagents;
repeat reading for that
point; average new and
original values; replot
Take corrective action
(recalibrate if necessary),
and reanalyze the last 10
samples.
-------
Jan. 1983 1 Section 2.1.6
6.0 Data Reduction, Validation, and Reporting
The quality control activities are
summarized in Table 6.1 at the end of
this section
6.1 Flow Rate Data Review
Samples should be invalidated if the
difference between the initial and
final flow rate is greater than 5
percent
6.2 SO2 Data Review
The analytical data should be
invalidated if any of the following
conditions exist regarding SOz
calibration.
1. Fresh reagents are not used.
2. The internal control samples
were analyzed, and the results
deviated by more than ±1 /jg SOz
from the known value, but a new
calibration curve was not constructed.
3. The slope of the final calibration
curve was not within 0.03 ±0.002
absorbance units/£ig SO2.
4. The intercept of the final
calibration curve was not <0.17 at
22°C (72°F) with a 1 -cm optical path
length, and/or the blank was not
within ±0.03 of the regression
intercept.
5. The correlation coefficient of the
least square regression was <0.998.
6.3 Standardize Format
Reporting
The standardized procedure for
reporting is as follows:
1. Record the 24-h sample
analytical results on the SAROAD
daily data form (Figure 6.1).
2. Record the 30-min or the 1-h
sample analytical results on the
SAROAD hourly data form (Figure
6.2).
3. Refer to EPA-450/2-76-029,
Dec. 1976, OAQPS Guidelines,
AEROS Manual Series, Volume II:
AEROS User's Manual, U.S. EPA
Office of Air and Waste Management,
Research Triangle Park, North
Carolina.
-------
Section 2.1.6
Jan. 1983
24-Hour or Greater Sampling Interval
Town Pollution
1 Agency
Town
State
Area
Site
City Name
4QO
Site Address
Project
2$ how
Time Interval
i
6
2 3
Agency
P
0
7
4 5
Project
0
z
0
6
0
7
Time
7
0
8
O
I
9 10
Year
7
h
Month
0
z
11
12 13
14
15 16
17 18
19 20
SO?
Name
PARAMETER
Code
21 2
0
O
4-
23
9
2
24
/
28 :
2
0
o
^ \O
>S
33
O
£>
5 26
0
/
27
/
0
30 31 32
34 35 36
2.
y.
7
;Z
9
8
Name
PARAMETER
Code
37 38 39
42
40
41
43 44 45 46
47 48 49 50
Name
PARAMETER
Code
51 52 53 54 55
56
57 58 59
61 62 63 64
\
60
Name
PARAMETER
Code
65 66 67 68 69
70
71 72 73 74
75 76 77 78
|
DP- 43210
Figure 6 1 SAROAD daily data form
4 3
1 U
-------
Jan. 1983
Section 2.1.6
!I5
^
0
ts
S,
-------
Section 2.1.6 4 Jan. 1983
6.4 Filing the Calculations
1. Identify all of the sample
calculations with the sample numbers
and dates.
2. File the calculations in the
laboratory data log book.
Table 6.1 Activity Matrix for Data Reduction, Validation, and Reporting
Activity
Flow data
SOz data
Documentation and report
of results
Acceptance limits
Deviation in flow rates
less than ±5%
Five conditions of Sub-
sec 6.2 met
All needed data available
Frequency and method
of measurement
Visually observe reported
data
As above
As above
Action if
requirements
are not met
Void the sample
As above
As above
-------
Jan. 1983
Section 2.1.7
7.0 Maintenance
7.1 The 24-h Bubbler Train
Every 3 months or every 15
sampling periods, whichever occurs
first, the following components should
be replaced.
1. Membrane filter - Replace the
membrane filter by removing the
Tygon tubing from the inlet and outlet
of the plastic filter holder (The filter
and filter holder are disposable ) Seal
the new filter holder to prevent
leakage by pulling the filter holder
apart and coating the junction of
the two halves with a thin layer of
cyclohexanone and by rejoining the
two halves and pressing them
together until they are dry Connect
the new filter in place
2 Mist trap - Change the trap by
removing the Tygon tubing and
replacing it with a clean dry trap
Disassemble the trap that was
removed, wash it, and allow it to dry
before reassembling and using it
again.
3. Rubber septa - Remove the old
septa from the glass adapters, and
replace them with new septa.
4. Vacuum gauge - Check the
vacuum gauge against a calibrated
vacuum guage or a mercury
manometer. Replace the guage if it is
defective, (not within ±25 mm (±1
m.) Hg).
5 Vacuum tubing - Replace the
black vacuum tubing with a new
section to minimize the possibility of
leakage.
6 Vacuum pump - If the vacuum
pump cannot provide >530 mm (>21
in ) Hg vacuum at 760 mm (29.92 in.)
atmospheric pressure, replace its
carbon vanes or its diaphragm. At an
atmospheric pressure of 760 mm, the
530 mm (21 in.) Hg vacuum provides
a safety margin of 100 mm (3.9 in.)
Hg vacuum
7.2 The Short-Term
Sampling Train
Every 3 months or every 30
sampling periods, whichever occurs
first, the following components should
be serviced-
1 Rotameters - Disassemble and
clean the rotameters with detergent,
and rinse with distilled water and
alcohol Recalibrate before use.
2 Mist trap - Clean the trap, and
replace the glass wool
3 Needle valve - Inspect the valve
for proper seating of the stem, check
the valve-stem packing nut for proper
tension, and clean the valve with
detergent Rinse with distilled water
and alcohol
4. Vacuum pump - Perform the
same maintenance as that described
in Subsection 7 1
5. Vacuum tubing - Perform the
same maintenance as that described
in Subsection 7 1
7.3 Calibration Equipment
and Related Apparatus
Periodic maintenance requirements
for equipment such as the mass -flow
meters, soap-bubble meters, and
spectrophotometers vary with the
specific manufacturer. Thus, the
manufacturer's recommendations
should be followed as well as one's
own experience.
Table 7.1 Activity Matrix for Regular and Preventive Maintenance
Equipment
Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
24-h bubbler train
Vacuum gauge
Vacuum pump
Short-term sampling tram
Calibration equipment and
related apparatus
Membrane filter, mist trap,
rubber septa, and vacuum
tubing replaced regularly.
Readings correct within
±254 mm (±1 in.) Hg
Capability to provide at
least 530 mm (21 in J
Hg vacuum at STP.
Rotameter, mist trap
needle valve, vacuum
pump, and vacuum ser-
viced regularly.
Maintained periodically
according to manufac-
turer's recommendations.
Replace every 3 mo or after
7 5 sampling periods.
Check every 3 mo against
calibrated vacuum gauge
or Hg manometer.
Test the vacuum.
Clean every 3 mo or after
30 sampling periods.
Follow manufacturer's
recommendations.
Implement maintenance
actions.
Rep/ace if defective.
Replace carbon vanes or
diaphragm; retest.
Implement maintenance
actions.
Implement maintenance
actions.
-------
Jan. 1983
Section 2.1.8
8.0 Auditing Procedure
An audit is an independent
assessment of the accuracy of data.
Independence is achieved by having
the audit made by an operator other
than the one conducting the routine
measurements and by using audit
standards and equipment different
from those routinely used in
monitoring.
The audit should be a true
assessment of the measurement
process under normal operations—
that is, without any special
preparation or adjustment of the
system. Routine quality assurance
checks conducted by the operator are
necessary for obtaining and reporting
good quality data, but they are not
considered part of the auditing
procedure.
Two types of audits are
recommended herein—performance
audits and system audits. Three
performance audits and one system
audit are detailed in Subsections 8.1
and 8.2 and summarized in Table 8.2
(at the end of this section). In addition
to these audits, the precision of the
entire measurement process is
assessed by comparing the
measurements made by collocated
samplers, as described in Sections
2.0.9 and 2.1.9.
Proper implementation of an
auditing program serves a twofold
purpose: to ensure the integrity of the
data and to assess the accuracy of the
data. The technique for estimating the
accuracy of the data is given in
Section 2.0.8 of this volume.
8.1 Performance Audits
Performance audits conducted by
another operator/analyst are
quantitative evaluations of the quality
of data produced by the total
measurement system (sample
collection, sample analysis, and data
processing). The following three
performance audits of individual
variables are recommended:
1. Audit of flow rate for sample
collection.
2. Audit of analysis process by use
of reference samples (mandatory).
3. Audit of data processing. (Refer
to Appendix A for auditing frequency.)
Auditing of 7 of 100 sampling
periods for each site is suggested as a
starting frequency for the first and
third audits; frequency for the second
audit is given in Subsection 8.1.2.
Where one sample is collected every
6th day, one audit per month at each
site is recommended; if the data are
reported quarterly, this would mean
auditing 3 of each 15 sampling
periods. If the number of sampling
periods is >1 5 but <50, four audits
are recommended. These are the
suggested starting frequencies; they
should be altered if either experience
or data quality indicate a need for
change. For example, the frequency
should be reduced if experience
indicates that data are of good quality;
the opposite would apply if the data
were of poor quality
In a determination of the number of
audits needed, it is more important to
be sure that the audit sample is
representative of the various
conditions that may influence the data
quality than to adhere to a fixed
frequency. The supervisor will specify
the frequencies according to
mointoring requirements.
8.1.1 Flow Rate Audit - For 30-min,
1-h, and 24-h samples, a flow rate
audit is recommended to assess the
sampling collection phase of the
measurement process. The audit
should be performed as follows.
1. Have the regular operator
prepare the sampler for sample
collection as usual; this must include
filling in the sample record form
(Figure 4.10).
2. Have the operator compute the
average sampled volume, Vm, as
measured by the regular flow
measurement device and corrected to
reference conditions (if necessary).
3. Insert the audit device in the
sample inlet line and measure the
flow in the usual manner at the
beginning and at the end of the
sampling period.
4. Calculate the average audited
volume, Va, at reference conditions for
the audit device (Va = Qat, where Qa is
the average audited flow rate in
liters/minute and t is the sampling
time in minutes).
5. Compute the percent difference,
d (a measure of inaccuracy):
100.
Equation 8-1
6. Record Vm, Va, and d. It is
recommended that the d's be plotted
on the X-and-R chartjas illustrated in
Figure 8.1. (Only the X chart is used
for quality_control of accuracy; the
standard X-and-R chart is used for
convenience.) If d is greater than ±7%
or if Vm/Va does not fall between 0.93
and 1.07, begin the troubleshooting
and take corrective action before
resuming the sampling. All flow rate
data for the audit period is invalidated
if an unexplained malfunction has
occurred and resulted in errors in the
flow rates.
8.1.2 A udit of A nalysis Process
Using Reference Samples - Reference
(audit) samples should be included at
ramdom at the recommended
frequency among the samples
awaiting analysis. If possible, they
should not be recognizable to the
analyst as reference samples. The
audit procedure for the SOa method is
as follows:
1. Prepare the audit solutions from
a working sulfite-TCM solution, as
described previously in Subsection
3.12 of Section 2.1.3. Prepare these
audit samples independently from the
standardized sulfite-TCM solution
used in the routine analysis
procedure. Prepare new sulfite-TCM
audit samples every 30 days, and
store them between 0° and 5°C.
2. Prepare the audit samples in
each of the concentration ranges of
0.2 to 0.3, 0.5 to 0.6, and 0.8 to 0.9
yug S02/ml.* Analyze an audit sample
in each of the three ranges at least
once each day that samples are
analyzed and at least twice per
calendar quarter. The differences
between the measured concentrations
(/ug SOa/ml) and the audit
concentrations are used to calculate
the percent difference (a measure of
inaccuracy) as described in Section
2.0.8. The calculation for percent
difference for individual audit samples
is also shown here at Item 3.
3. The agency/organization
determines the percent difference (d)
between the measured SOz
concentration and the audit or known
*ln the event that the absorption is plotted
against the total SOz contained in 25 ml, the
concentration ranges should be multiplied by 25.
This same adjustment should be applied to all
corresponding data in this section.
-------
Section 2.1.8
Jan. 1983
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Jan. 1983
Section 2.1.8
values of concentration. The d is a
measure of both the bias and the
random error of the analytical phase
of the S02 reference method.
Calculate d by using Equation 8-2.
d =
Cso2 (M) - Cso2 (A)
Cso2 (A)
x100
Equation 8-2
where
Cso2 (M) = concentration measured.
by the lab analyst /ug/ml
Cso2 (A)= audit or known
concentration of the audit
sample, jug/ml.
The recommended control limits for
the three audit sample ranges (0.2 to
0.3, 0.5 to 0.6, and 0.8 to 0.9 //g
SOa/ml) are the 90th percentile value
for d based on the results of five
audits (11/76, 4/77, 10/77, 4/78,
and 10/78) performed by the
Environmental Monitoring Systems
Laboratory, USEPA, Research Triangle
Park, North Carolina.9'10 By definition,
90 percent of the laboratory
participants in the audit obtained
values of d less than the values
tabulated below. The control limits
are expected to be exceeded by 10
percent of the laboratories to be
audited, based on these five audits.
The 90th percentile values and the
known audit concentrations are given
below for each audit concentration
range.
Based on the results or these five
audits, the recommended 90th
percentile control limits for audit
samples are ±33 percent for the 0.2
to 0.3 fjg SOz/ml concentration range
and ±18 percent for both the 0.5 to
0.6 and the 0.8 to 0.9 fjg S02/ml
concentration ranges.
It is recommended that each
laboratory participate in the EPA
National Performance Audit program
as described in Section 2.1.5,
Subsection 5.4. This will serve as an
independent audit of the analysis
technique.
8.1.3 Data Processing Audit - The
data processing audit is most
conveniently performed soon after the
original calculations have been
completed, so that corrections can be
made immediately and additional
explanatory data can be retrieved from
field personnel when necessary. The
procedural steps are as follows.
1. The audit must be performed by
an individual other than the one who
originally reduced the data. The check
should start with the raw data and
continue through the recording of the
concentration (/ug SOz/m3) on the
SAROAD form.
2. If the mass concentration of SOa
computed by an audit does not agree
with the original or indicated value
within round-off error, the
calculations for all samples collected
since the previous audit should be
checked and corrected. The audit
value is always reported as the
0.2 to 0.3 ug SOz/ml
Audit date
11/76
4/77
10/77
Audit date
11/76
4/77
10/77
10/77
10/78
Audit date
11/76
" 4/77
70/77
4/78
10/78
Known audit
concentration
itg SOz/ml
0.259
0.289
0.338
0.5 to 0.6 ug SOz/ml
Known audit
concentration
ua SOz/ml
0.617
0.688
0.562
0.562 duplicates
0.533
0.8 to 0.9 uff SOz/ml
Known audit
concentration
ug SOz/ml
0.895
0.930
1.07
0.755
0.757
90th percentile for d,
33
32
35
90th percentile for d.
24
17
18
17
18
90th percentile for d.
18
23
16
17
17
correct value, under the assumption
that the audit should be checked if a
discrepancy exists and corrected if
necessary.
3. The audit and the original values
and the percentage difference should
be recorded in the laboratory log book
and reported to the supervisor.
8.2 System Audit
A system audit is an onsite
inspection and review of the quality
assurance system used for the total
measurement system (sample
collection, sample analysis, data
processing, etc.). A system audit is a
qualitative appraisal of system quality.
A system audit should be conducted
at the startup of a new monitoring
system and thereafter as appropriate
to ascertain significant changes in
system operations. A checklist for use
in a system audit is provided in Figure
8.2. These questions should be
reviewed for their applicability to the
particular local, State, or Federal
agency being audited.
-------
Section 2.1.8
Jan. 1983
1, What type of manual sampler is used for SOi collection'
(a) RAC <@)j)5-pon (c) 2-port (d) other
2. Is a straight tube impinger used in the polypropylene sampling tube?
3. Is sample probe made of accepted material? Teflon® Glass /L.
4. Is the probe (and manifold) located to prevent moislurecnndensation when sampling in humid conditions?
5. What method of analysis is used? rf*fm fvt cL-x-Qiy^^g^t—• /s a copy available? ^^>*—' (Metltbd should be from 40
CFR 50. July 1, 1982. as amended 47 FR 54896, Dece,
6. What quality of reagents is used to make up the chemicals for the SO2 analysis?
(They should be reagent grade or better
7. Is the sampling tram routinely checked for leaks? _^t*^=i
How often? (a) Once a week (b) Once a month (cfl)nce a quarter (d) other
8. What calibration check procedure is used for flow measuring device used in the field?
Is a written copy available?
9. Are samp/ing flow rates determined before and after each samp/ing period?
discarding needles that are not within flow rate limits initially?
If &what are the limits? .
. Is there an established procedu/g fpr
\lAny
needle outside of 180 to 200 cm3/mm should be discarded for 24'h samples) Is the absorbing solution maintained af 15° +10°C?
.Are samples voided? sUJt*— Do initial and final flow rates agree within +5%?t4ftfJO^f—/(Void sample if they are
not.)
10. Have calibration curves been made, and are they available?
other type) of notebook, and is it readily available?
Is the calibration history of the analyses in a bound lor
(All laboratories must keep a bound notebook as a permanent recort
made and what points were used to make them.)
of the calibration history that indicates when the curves were
11. Are collected samples shipped from the field to the laboratory in containers that prevent crushing, spilling, etc, and maintained at a
temperature of 5°± 5°C? ^^*tf^
12. How many days were there Between sampling and analysis? J^ days (Commonly it is approximately 12 days, less than 12
is very good, but more than 12 may cause problems in analysis )
13. Are samples stored in the dark until they are analyzed? .
14. What calculations were performed to obtain the final S02 Concentration?
(If possible, show the completed calculations.)
15. How were discrepancies in the data treated?
. At what temperature are {he samples stored?
16. Are the data reported quarterly? ^•tf^a. • If not, how often?
figure 8.2 Checklist for use by auditor for SOz method
(There should be a format for taking care of data discrepancies)
Table 8.1 Activity Matrix for Auditing Procedure
Audit
Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
Flow rate
Audit of analysis process
using audit samples
Data processing
System audit
0.93 < V™ <-1.07, where
Va
l/m = routinely measured
sample volume, and
Va - audited volume
The value of d should be
within ±33% for 0.2 to 0.3
/jg SC>2/ml concentration
range, and within ±18%
for both the 0.5 to 0.6 and
0.8 to 0.9 ug SOz/ml
concentration ranges
(Subsec. 8.1.2).
The reported value should
agree with the audited
value within round-off
error.
Method is described in this
section of Handbook.
Once per 14 days of
sampling or 1 /mo, which-
ever is greater; calibrated
flow measuring device.
Analyze an audit sample in
each of the three concen-
tration ranges at least once
each day and at least twice
per calendar quarter that
samples are analyzed
(Subsec. 8.1.2).
Once per 14 samples or
1 /mo, whichever is
greater; independent
calcualtions from raw data
to final recorded data.
At the beginning of a new
monitoring system, and
periodically as appropriate;
observation of procedures
and use of a checklist.
Take corrective action
before resuming Campling
action noted on X-and-R
chart.
Check calibration curve, if
necessary; check a new
reference sample, and if
acceptable, resume anal-
ysis; calculate data accu-
racy per Sec. 2.0.8.
Check and corret calcula-
tions for all samples col-
lected since previous audit.
Initiate improved methods
and/or training programs.
-------
Jan. 1983
Section 2.1.9
9.0 Assessment of Monitoring Data for Precision and Accuracy
V
m
9.1 Precision
Collocated samplers should be used
to assess the precision of the SOz
Reference Method data. For each
monitoring network, an additional
sampler should be collocated from at
least one site (two sites are required
for SLAMS). A site with the highest
expected geometric mean should be
selected. The two samplers should be
located at the same elevation and
within 4 m of each other One of the
two samplers should be identified as
the one for normal routine monitoring,
and the other as the duplicate
sampler. The calibration, sampling,
and analysis must be the same for
both collocated samplers and for all
other samplers in the network, and
the collocated samplers must be
operated when the routine samplers
are operated.
The differences in concentrations
(A/g/m3) recorded between the routine
and the duplicate samplers are used
o calculate precision (as described in
Section 2.0.8 of this Handbook).
Based on a series of tests under
well-controlled conditions in an EPA
laboratory, the mean and standard
deviations of S02 concentrations for
several samples collected simultane-
ously by five sampling trains using a
common manifold are given in the
first two columns of Table 9 1 These
results indicate that the standard de-
viation (s) is dependent or^the aver-
age S02 concentrations (X) for the five
trains. In the third column of Table
9.1, the relative standard deviation
(RSD, or the coefficient of variation) is
computed and given as RSD =
100s/X. Columns 4 and 5 were ob-
tained by multiplying the values in
columns 2 and 3 by 3Y"2. These values
are the expected agreements between
each two collocated samplers on the
same manifold under well-controlled
conditions, and they estimate the 3<5-
control limits that correspond to
values that should include about 99.7
percent of the differences between
the two sample values under "ideal"
laboratory conditions. The 3<5 limits
[expressed as percentages of the aver-
age concentration (75 values in the
last column of Table 9.1] are plotted
in Figure 9.1. Values read from the
smooth curve drawn through the data
points with a minimum near 365 fjg
SCb/m3 would be the recommended
3cr limits under the best conditions of
sampling and analysis.
Actual field data for collocated
samplers show a trend similar to that
m Figure 9.1; however, the 3a limits
are much larger. For concentrations
>75 fjg S02/m3, the 3a limits of
agreement are about 45 percent of
the average concentration; for low
concentrations these limits often
exceed 100 percent.
Based on experimental data in Table
9.1 and on the actual field test data,
poor agreement may be expected
between collocated samplers when
measured concentrations are <75 ug
SOz/m3.
9.2 Accuracy
The accuracy of the pararosanilme
method for measurement of SOz is
assessed as described in Section
2.1.8, Auditing Procedure. The
accuracy of a single instrument is
calculated as shown in Section 2.0.8
and 2.1.8 of this volume of the
Handbook.
Table 9.1
Experimental Data and Expected Agreement Between Two Collocated S02 Sampling Trains on a Common
Manifold Under Well-Controlled Conditions
Experimental data
Expected agreement
between collocated
(two) sampling trains*
3a - control limits
Average (X),
t*9 SOz/m3
16.7
35.6
37.8
71 2
72.4
73.9
177
201
344
684
694
927
Standard
deviation (s),
UQ SOz/m3
2.53
4.52
3.13
4.54
1.17
3.43
5.81
3.37
261
17.8
27 1
44.9
Relative
standard
deviation
(100s/X)
15.1
12.7
83
64
1 6
4.6
3.3
1.7
0.8
26
3.9
4.8
UQ SOz/m3
10.7
19.2
13.3
19.3
5.0
14.6
24.6
14.3
11.1
75.5
115
190
Percentage of
average
concentration
64
54
35
27
7
20
14
7
3
11
17
20
'Based on 24-h samples obtained by one analyst using five trains on a common manifold. (Fuerst, R.G. Effect of
Temperature on Stability of Sulfur Dioxide Samples. Unpublished research by the Environmental Monitoring and
Support Laboratory, Research Triangle Park. N.C., March 1976).
'Results in columns 4 and 5 (calculated by multiplying the results in columns 2 and 3, respectively by 3^2) were plotted
as an eye-fitted smooth curve (Figure 9-1) to provide 3a control limits which represent the best agreement that might
be expected for collocated samplers using the SOz Reference Method.
-------
Section 2.1.9
Jan. 1983
80
70
60
50
40
IS
5J 30
§ | 20
10
100 200 300 4OO 5OO 60O
Mean Concentration, /jg SO2/m3
700 800
900 WOO
Figure 9.1 Agreement between collocated (two) SO2 samp/ing trains under well-controlled conditions (based on laboratory
experimental data in Table 9.1).
-------
Jan. 1983
Section 2.1.10
10.0 Recommended Standards for Establishing Traceability
Two considerations are essential to
achieving data of the desired quality:
(1) the measurement process must be
in a state of statistical control at the
time of the measurement, and (2)
when the systematic errors are
combined with the random variation
(errors of measurement) the result
must be a suitably small uncertainty.
Evidence in support of good quality
data is acquired by performing quality
control checks and independent audits
of the measurement process,
documenting these data, and using
materials, instruments, and
measurement procedures that can be
traced to an appropriate standard of
reference
Data must be routinely obtained by
repeat measurements of standard
reference samples and primary,
secondary, and/or working standards;
and a condition of process control
must be established. The working
calibration standards should be
traceable to standards of higher
accuracy, such as those presented
here.
1. Class-S weights (NBS
specifications) are recommended for
the analytical balance calibration. (See
Section 21 2 for details on balance
calibration checks )
2. Sulfur dioxide permeation tubes
should be traceable to NBS Standard
Reference Materials, Numbers 1625-
1627 " (See Section 2111,
Subsection 10.3, for details on
calibration using SC>2 permeation
tubes.)
3. Reagents should be at least
American Chemical Society (ACS)
reagent-grade chemicals. Such
reagents have been certified to
contain impurities in concentrations
below the specifications of the
Committee of Analytical Reagents of
the ACS. Each reagent bottle is
identified by ACS with a batch
number. Potassium lodate reagent
must be of primary standard quality.
4 The complete absorbance scale
should be checked with a calibrated
set of NBS filters (SRM's 2101-
210511) periodically and anytime a
control sample cannot be measured
within the control limit assigned to it.
(See Section 2.1.5 for details of
spectrophotometer calibration )
5. The spectrophotometer should be
checked for proper wavelength
calibration throughout the range of
the instrument. A Didymium Glass
filter* may be used. This filter has five
well-defined absorbance maxima
between 400 and 900 mm. The
known peak maximum at 585 mm
should agree within ± 5 mm of the
measured peak maximum or remedial
action should be taken.
6. All calibrations of flow
measurement devices are directly
traceable to primary displacement
methods.
'Available from Arthur H Thomas Company
(Philadelphia, Pennsylvania)
-------
Jan. 1983
Section 2.1.11
11.0 Reference Method
Appendix A—Reference Method for
the Determination of Sulfur Dioxide
in the Atmosphere (Paraosaniline
Method)
[Appendix A revised by 47 FR
54899, December 6. 1982]
1.0 Applicability
1.1 This method provides a
measurement of the concentration of
sulfur dioxide (SOz) in ambient air for
determining compliance with the
primary and secondary national
ambient air quality standards for
sulfur oxides (sulfur dioxide) as
specified in § 50.4 and § 50.5 of this
chapter. The method is applicable to
the measurement of ambient SOz
concentrations using sampling periods
ranging from 30 minutes to 24 hours.
Additional quality assurance
procedures and guidance are provided
in Part 58, Appendixes A and B, of
this chapter and in references 1 and
2.
2.0 Principle.
2.1 A measured volume of air is
bubbled through a solution of 0.04 M
potassium tetrachloromercurate
(TCM). The SOa present in the air
stream reacts with the TCM solution
to form a stable
monochlorosulfonatomercurate(3)
complex. Once formed, this complex
resists air oxidation (4, 5) and is
stable in the presence of strong
oxidants such as ozone and oxides of
nitrogen. During subsequent analysis,
the complex is reacted with acid-
bleached pararosaniline dye and
formaldehyde to form an intensely
colored pararosaniline methyl sulfonic
acid(6). The optical density of this
species is determined
spectrophotometrically at 548 nm and
is directly related to the amount of
SO: collected. The total volume of air
sampled, corrected to EPA reference
conditions (25°C, 760 mm Hg [101
kPa]), is determined from the
measured flow rate and the sampling
time. The concentration of S02 in the
ambient air is computed and
expressed in micrograms per standard
cubic meter (ug/std m3).
•40 CFR 60, July 1, 1982, as amended 47 FR
54896, December 6, 1982 and 48 FR 17355,
April 22, 1983.
3.0 Range.
3.1 The lower limit of detection of
S02 in 10 mL of TCM is 0.75 fjg
(based on collaborative test results)
(7). This represents a concentration of
25 fjg SC>2/m3 (0.01 ppm) m an air
sample of 30 standard liters (short-
term sampling) and a concentration of
13 fjg S02/m3 (0.005 ppm) in an air
sample of 288 standard liters (long-
term sampling). Concentrations less
than 25 fjg SOa/m3 can be measured
by sampling larger volumes of
ambient air; however, the collection
efficiency falls off rapidly at low
concentrations (8.9). Beer's law is
adhered to up to 34 fjg of SO2 in 25
mL of final solution. This upper limit
of the analysis range represents a
concentration of 1.130/yg SOz/m3
(0.43 ppm) in an air sample of 30
Standard liters and a concentration of
590 fjg Spz/m3 (0.23 ppm) in an air
sample of 288 standard liters. Higher
concentrations can be measured by
collecting a smaller volume of air, by
increasing the volume of absorbing
solution, or by diluting a suitable
portion of the collected sample with
absorbing solution prior to analysis.
[Corrected by 48 FR 17355, April 22,
1983]
4.0 Interferences.
4.1. The effects of the principal
potential interferences have been
minimized or eliminated in the
following manner: Nitrogen oxides by
the addition of sulfamic acid (10, 11)
heavy metals by the addition of
ethylenediamine tetracetic acid
disodium salt (EDTA) and phosphoric
acid. (10, 12) and ozone by time delay
(10). Up to 60 fjg Fe (III), 22 fjg V (V),
lO^g Cu (II), 10 fjg Mr, (II), and 10//g
Cr (III) in 10 mL absorbing reagent can
be tolerated in the procedure (10). No
significant interference has been
encountered with 2.3 fjg NH3 (13).
5.0 Precision and Accuracy.
5.1 The precision of the analysis is
4.6 percent (at the 95 percent
confidence level) based on the
analysis of standard sulfite samples
(10).
5.2 Collaborative test results (14)
based on the analysis of synthetic test
atmospheres (SC<2 in scrubbed air)
using the 24-hour sampling procedure
and the sulfite-TCM calibration
procedure show that:
• The replication error varies
linearly with concentration from
±2.5 fjg/m3 at concentrations of
100//g/m3 to ±7 /jg/m3 at
concentrations of 400 /ug/m3.
• The day-to-day variability within
an individual laboratory
(repeatability) varies linearly with
concentration from ±18.1 fjg/m3
at levels of 100 fjg/m3 to ±50.9
fjg/m3 at levels of 400 fjg/m3.
• The day-to-day variability
between two or more
laboratories (reproducibility)
varies linearly with concentration
from ±36.9 fjg/m3 at levels of
100/yg/m3 to ±103.5//g/m3 at
levels of 400 //g/m3.
• The method has a concentration
dependent bias which becomes
significant at the 95 percent
confidence level at the high
concentration level. Observed
values tend to be lower than the
expected SOz concentration level.
6.0 Stability.
6.1 By sampling in a controlled
temperature environment of 15°
±10°C, greater than 98.9 percent of
the SOz—TCM complex is retained at
the completion of sampling (15). If
kept at 5°C following the completion
of sampling, the collected sample has
been found to be stable for up to 30
days (10). The presence of EDTA
enhances the stability of SOz in the
TCM solution and the rate of decay is
independent of the concentration of
S02(16).
7.0 Apparatus.
7.1 Sampling.
7.1.1 Sample probe: A sample probe
meeting the requirements of
Section 7 of 40 CFR Part 58,
Appendix E (Teflon® or glass with
residence time less than 20 sec.) is
used to transport ambient air to the
sampling train location. The end of
the probe should be designed or
oriented to preclude the sampling of
precipitation, large particles, etc. A
suitable probe can be constructed
from Teflon® tubing connected to an
inverted funnel.
-------
Section 2.1.11
Jan. 1983
7.1.2 Absorber—short-term
sampling: An all glass midget
impmger having a solution capacity of
30 mL and a stem clearance of 4±1
mm from the bottom of the vessel is
used for samplymg periods of 30
minutes and 1 hour (or any period
considerably less than 24 hours).
Such an impinger is shown in Figure
1. These impingers are commercially
available from distributors such as
Ace Glass, Incorporated.
7.1.3 Absorber—24-hour sampling:
A polypropylene tube 32 mm in
diameter and 164 mm long (available
from Bel Art Products, Pequammock,
NJ) is used as the absorber. The cap
of the absorber must be a polypropylene
cap with two ports (rubber stoppers
are unacceptable because the
absorbing reagent can react with the
stopper to yield erroneously high SOz
concentrations). A glass impinger
stem, 6 mm in diameter and 158 mm
long, is inserted into one port of the
absorber cap. The tip of the stem is
tapered to a small diameter orifice
(0.4±0.1 mm) such that a No. 79
jeweler's drill bit will pass through the
opening but a No. 78 drill bit will not.
Clearance from the bottom of the
absorber to the tip of the stem must
be 6+2 mm. Glass stems can be
fabricated by any reputable glass
To Sample
Probe
blower or can be obtained from a
scientific supply firm. Upon receipt, the
orifice test should be performed to
verify the orifice size. The 50 mL
volume level should be permanently
marked on the absorber. The
assembled absorber is shown in
Figure 2.
7.1.4 Moisture trap: A moisture trap
constructed of a glass trap as shown
in Figure 1 or a polypropylene tube as
shown in Figure 2 is placed between
the absorber tube and flow control
device to prevent entrained liquid
from reaching the flow control device.
The tube is packed with indicating
silica gel as shown in Figure 2. Glass
wool may be substituted for silica gel
when collecting short-term samples (1
hour or less) as shown in Figure 1, or
for long term (24 hour) samples if
flow changes are not routinely
encountered.
7.1.5 Cap seals: The absorber and
moisture trap caps must seal securely
to prevent leaks during use. Heat-
shrink material as shown in Figure 2
can be used to retain the cap seals if
there is any chance of the caps
coming loose during sampling,
shipment, or storage.
7.1.6 Flow control device: A
calibrated rotameter and needle valve
Hypodermic
Needle
Impingers
(See Below)
6 mm /.D.-H
5
8
30 ml.
20 ml.
10 ml.
Critical Orifice Flow Control
''-<
To Vacuum
Pump
r
/ 25 mm
/ O.D.
Inside
Clearance
3 to 5 mm
10 mm O.D.
I
, 24/40 Concentric with
' outer piece and with
nozzle.
(• Graduations at 5 ml.
intervals. All the
way around.
Nozzle I.D. Exactly
. 1 mm; passes 0.09 to 0.11
cfm at 12 in. H2O vacuum.
Pieces should be inter-
changeable, maintaining
nozzle centering and
clearance to bottom
inside surface
To Vacuum
Pump
Needle
Valve
Flowmeter
Alternative Flow Control
Glass Wool or
Silica Gel
All-Glass Midget Impinger
(This is a commercially
stocked item)
Figure 1. Short term sampling train.
combination capable of maintaining
and measuring air flow to within +2
percent is suitable for short-term
sampling but may not be used for
long-term sampling. A critical orifice
can be used for regulating flow rate
for both long-term and short-term
sampling. A 22-gauge hypodermic
needle 25 mm long may be used as a
critical orifice to yield a flow rate of
approximately 1 L/min for a 30-
minute sampling period. When
sampling for 1 hour, a 23-gauge
hypodermic needle 16 mm in length
will provide a flow rate of
approximately 0.5 L/min. Flow control
for a 24-hour sample may be provide
by a 27-gauge hypodermic needle
critical orifice that is 9.5 mm in
length. The flow rate should be in the
range of 0.18 to 0.22 L/min.
7.1.7 Flow measurement device:
Device calibrated as specified in 9.4.1
and used to measure sample flow rate
at the monitoring site.
7.1.8 Membrane particle filter: A
membrane filter of 0.8 to 2 ym
porosity is used to protect the flow
controller from particles during long-
term sampling. This item is optional
for short-term sampling.
7.1.9 Vacuum pump: A vacuum
pump equipped with a vacuum gauge
and capable of maintaining at least 70
kPa (0.7 atm) vacuum differential
across the flow control device at the
specified flow rate is required for
sampling.
7.1.10 Temperature control device:
The temperature of the absorbing
solution during sampling must be
maintained at 15° ± 10°C. As soon as
possible following sampling and until
analysis, the temperature of the
collected sample must be maintained
at 5° ± 5°C. Where an extended
period of time may elapse before the
collected sample can be moved to the
lower storage temperature, a
collection temperature near the lower
limit of the 15 ± 10°C range should
be used to minimize losses during this
period. Thermoelectric coolers
specifically designed for this
temperature control are available
commercially and normally operate in
the range of 5° to 15°C. Small
refrigerators can be modified to
provide the required temperature
control; however, inlet lines must be
insulated from the lower temperature;
to prevent condensation when
sampling under humid conditions. A
small heating pad may be necessary
when sampling at low temperatures
-------
Jan. 1983
Section 2.1.11
Teflon, Polypropylene,
or Glass
Polypropylene
2-Port Tube Closure
Glass
Impinger
Stem
Poly prop ylene
Tube
Absorber for
24h Sampler
Note. A midget tmpmger is
used for 1 hour
sampling
Figure 2. 24-Hour sampling system
(<7°C) to prevent the absorbing
solution from freezing (17).
7.1.11 Sampling train container:
The absorbing solution must be
shielded from light during and after
sampling. Most commercially available
sampler trains are enclosed m a light-
proof box.
7.1.12 Timer: A timer is
recommended to initiate and to stop
sampling for the 24-hour period. The
timer is not a required piece of
equipment; however, without the
timer a technician would be required
to start and stop the sampling
manually. An elapsed time meter is
also recommended to determine the
duration of the sampling period.
7.2 Shipping.
7.2.1 Shipping container: A shipping
container that can maintain a
temperature of 5° ± 5°C is used for
transporting the sample from the
ollection site to the analytical
boratory. Ice coolers or refrigerated
shipping containers have been found
to be satisfactory. The use of eutectic
cold packs instead of ice will give a
Trap
more stable temperature control. Such
equipment is available from Cole-
Parmer Company, 7425 North Oak
Park Avenue, Chicago, IL 60648.
7.3 Analysis.
7.3.1 Spectrophotometer: A
spectrophotometer suitable for
measurement of absorbances at 548
nm with an effective spectral
bandwidth of less than 15 nm is
required for analysis If the
spectrophotometer reads out in
transmittance, convert to absorbance
as follows.
A=log10(1/T) (1)
where
A= Absorbance, and
T= transmittance (0
-------
Section 2.1.11
Jan. 1983
storage of spent TCM solution. This
vessel should be stoppered and stored
in a hood at all times
8.0 Reagents.
8.1 Sampling
8.1.1 Distilled water: Purity of
distilled water must be verified by the
following procedure (18).
• Place 0.20 ml of potassium
permanganate solution (0.316
g/L), 500 mL of distilled water,
and 1 mL of concentrated sulfuric
acid in a chemically resistant
glass bottle, stopper the bottle,
and allow to stand.
• If the permanganate color (pink)
does not disappear completely
after a period of 1 hour at room
temperature, the water is
suitable for use.
• If the permanganate color does
disappear, the water can be
purified by redistilling with one
crystal each of barium hydroxide
and potassium permanganate in
an all glass still.
8.1.2 Absorbing reagent (0.04 M
potassium tetrachloromercurate
[TCM]): Dissolve 10.86 g mercuric
chloride, 0.066 g EDTA, and 6.0 g
potassium chloride in distilled water
and dilute to volume with distilled
water in a 1,000-mL volumetric flask.
(Caution: Mercuric chloride is highly
poisonous. If spilled on skin, flush
with water immediately.) The pH of
this reagent should be between 3.0
and 5.0 (10). Check the pH of the
absorbing solution by using pH
indicating paper or a pH meter. If the
pH of the solution is not between 3.0
and 5.0, dispose of the solution
according to one of the disposal
techniques described in Section 13.0.
The absorbing reagent is normally
stable for 6 months. If a precipitate
forms, dispose of the reagent
according to one of the procedures
described m Section 13.0.
8.2 Analysis.
8.2.1 Sulfamic acid (0.6%): Dissolve
0.6 g sulfamic acid in 100 mL distilled
water. Prepare fresh daily.
8.2.2 Formaldehyde (0.2%): Dilute 5
mL formaldehyde solution (36 to 38
percent) to 1,000 mL with distilled
water. Prepare fresh daily.
8.2.3 Stock iodine solution (0.1 N):
Place 12.7 g resublimed iodine in a
250-mL beaker and add 40 g
potassium iodide and 25 mL water.
Stir until dissolved, transfer to a
1,000 mL volumetric flask and dilute
to volume with distilled water.
8.2.4 Iodine solution (0.01 N):
Prepare approximately 0.01 N iodine
solution by diluting 50 mL of stock
iodine solution (Section 8.2.3) to 500
mL with distilled water.
8.2.5 Starch indicator solution
Triturate 0.4 g soluble starch and
0.002 g mercuric iodide (preservative)
with enough distilled water to form a
paste. Add the paste slowly to 200 mL
of boiling distilled water and continue
boiling until clear. Cool and transfer
the solution to a glass stoppered
bottle.
8.2.6 1 N hydrochloric acid: Slowly
and while stirring, add 86 mL of
concentrated hydrochloric acid to 500
mL of distilled water.
Allow to cool and dilute to 1,000 ml
with distilled water.
8.2.7 Potassium iodate solution:
Accurately weigh to the nearest 0.1
mg, 1.5 g (record weight) of primary
standard grade potassium iodate that
has been previously dried at 180°C
for at least 3 hours and cooled in a
dessicator. Dissolve, then dilute to
volume in a 500-ml. volumetric flask
with distilled water.
8.2.8 Stock sodium thiosulfate
solution (0.1N): Prepare a stock
solution by dissolving 25 g sodium
thiosulfate (Na2S2C>3 • 5 H2O) in 1,000
mL freshly boiled, cooled, distilled
water and adding 0.1 g sodium
carbonate to the solution. Allow the
solution to stand at least 1 day before
standardizing. To standardize,
accurately pipet 50 mL of potassium
iodate solution (Section 8.2.7) into a
500-mL iodine flask and add 2.0 g of
potassium iodide and 10 mL of 1 N
HCI. Stopper the flask and allow to
stand for 5 minutes. Titrate the
solution with stock sodium thiosulfate
solution (Section 8.2.8) to a pale
yellow color. Add 5 mL of starch
solution (Section 8.2.5) and titrate
until the blue color just disappears.
Calculate the normality (Ns) of the
stock sodium thiosulfate solution as
follows:
N, = W_x2.80
M (2)
where:
M = volume of thiosulfate required in
mL, and
W= weight of potassium iodate in g
(recorded weight in Section 8.2.7)s
and
103 (conversion of g to mg)
2.80 =x 0.1 (fraction iodate used)
35.67 (equivalent weight of
potassium iodate)
[Corrected by 48 FR 17355, April 22,
1983].
8.2.9 Working sodium thiosulfate
titrant (0.01 N): Accurately pipet 100
mL of stock sodium thiosulfate
solution (Section 8.2.8) into a 1,000-
mL volumetric flask and dilute to
volume with freshly boiled, cooled,
distilled water. Calculate the normality
of the working sodium thiosulfate
titrant (Nr) as follows:
NT=Nsx0.100
(3)
8.2.10 Standardized sulfite solution
for the preparation of working sulfite-
TCM solution: Dissolve 0.30 g sodium
metabisulfite (Na2S205) or 0.40 g
sodium sulfite (NaaSOs) m 500 mL of
recently boiled, cooled, distilled water.
(Sulfite solution is unstable, it is
therefore important to use water of
the highest purity to minimize this
instability.) This solution contains the
equivalent of 320 to 400 fjg S02/mL
The actual concentration of the
solution is determined by adding
excess iodine and back-titrating with
standard sodium thiosulfate solution.
To back-titrate, pipet 50 mL of the
0.01 N iodine solution (Section 8.2.4)
into each of two 500-mL iodine flasks
(A and B). To flask A (blank) add 25
mL distilled water, and to flask B
(sample) pipet 25 mL sulfite solution.
Stopper the flasks and allow to stand
for 5 minutes. Prepare the working
sulfite-TCM solution (Section 8 2.11)
immediately prior to adding the iodine
solution to the flasks. Using a buret
containing standardized 0.01 N
thiosulfate titrant (Section 8.2.9),
titrate the solution m each flask to a
pale yellow color. Then add 5 mL
starch solution (Section 8.2.5) and
continue the titration until the blue
color just disappears.
8.2.11 Working sulfite-TCM
solution: Accurately pipet 5 mL of the
standard sulfite solution (Section
8.2.10) into a 250-mL volumetric flask
and dilute to volume with 0 04 M TCM.
Calculate the concentration of sulfur
dioxide m the working solution as
follows:
32 (fig S02/mL) =
(A - B) (NT)(32,000) x 0 02
25 (4)
where:
A = volume of thiosulfate titrant
required for the blank, mL;
-------
Jan. 1983
Section 2.1.11
B = volume of thiosulfate
titrant required for the
sample, ml_;
NT= normality of the
thiosulfate titrant, from
equation (3),
32,000= milhequivalent weight of
SO2, fjig,
25 - volume of standard sulfite
solution, ml; and
0.02= dilution factor.
This solution is stable for 30 days if
kept at 5°C (16). If not kept at 5°C,
prepare fresh daily
[Corrected by 48 FR 17355, April 22,
1983]
8.2.12 Purified pararosaniline
(PRA) stock solution (0.2% nominal):
8.2.12.1 Dye specifications—
• The dye must have a maximum
absorbance at a wavelength of
540 nm when assayed in a
buffered solution of 0.1 M
sodium acetate-acetic acid;
• The absorbance of the reagent
blank, which is temperature
sensitive (0.015 absorbance
unit/°C), must not exceed 0.170
at 22°C with a 1-cm optical
path length when the blank is
prepared according to the
specified procedure;
• The calibration curve (Section
10.0) must have a slope equal to
0.030+0002 absorbance unit//ug
SO2 with a 1-cm optical path
length when the dye is pure and
the sulfite solution is properly
standardized
8.2.12.2 Preparation of stock PRA
solution—A specially purified (99 to
100 percent pure) solution of
pararosaniline, which meets the
above specifications, is commercially
available in the required 0.20 percent
concentration (Harleco Co.).
Alternatively, the dye may be purified,
a stock solution prepared, and then
assayed according to the procedure as
described below (10).
8.2.12.3 Purification procedure for
PRA—1. Place 100 ml each of 1-
butanol and 1 N HCI in a large
separatory funnel (250-mL) and allow
to equilibrate. Note: Certain batches of
1-butanol contain oxidants that create
an SO? demand. Before using, check
by placing 20 mL of 1-butanol and 5
ml of 20 percent potassium iodide (Kl)
solution in a 50-mL separatory funnel
and shake thoroughly. If a yellow
color appears in the alcohol phase,
redistill the 1-butanol from silver
oxide and collect the middle fraction
or purchase a new supply of 1-
butanol.
2. Weigh 100 mg of pararosaniline
hydrochloride dye (PRA) in a small
beaker. Add 50 mL of the equilibrated
acid (drain in acid from the bottom of
the separatory funnel in 1.) to the
beaker and let stand for several
minutes. Discard the remaining acid
phase in the separatory funnel.
3. To a 125-mL separatory funnel,
add 50 ml of the equilibrated 1-
butanol (draw the 1-butanol from the
top of the separatory funnel in 1.).
Transfer the acid solution (from 2.)
containing the dye to the funnel and
shake carefully to extract. The violet
impurity will transfer to the organic
phase.
4. Transfer the lower aqueous
phase into another separatory funnel,
add 20 ml of equilibrated 1-butanol,
and extract again.
5. Repeat the extraction procedure
with three more 10-mL portions of
equilibrated 1-butanol.
6. After the final extraction, filter
the acid phase through a cotton plug
into a 50-mL volumetric flask and
bring to volume with 1 N HCI. This
stock reagent will be a yellowish red.
7. To check the purity of the PRA,
perform the assay and adjustment of
concentration (Section 8.2.12.4) and
prepare a reagent blank (Section
11.2); the absorbance of this reagent
blank at 540 nm should be less than
0.170 at 22°C. If the absorbance is
greater than 0.170 under these
conditions, further extractions should
be performed.
8.2.12.4 PRA assay procedure—The
concentration of pararosaniline
hydrochloride (PRA) need be assayed
only once after purification. It is also
recommended that commercial
solutions of pararosaniline be assayed
when first purchased. The assay
procedure is as follows (10).
1. Prepare 1 M acetate-acetic acid
buffer stock solution with a pH of
4.79 by dissolving 13.61 g of
sodium acetate trihydrate in
distilled water in a 100-mL
volumetric flask. Add 5.70 mL of
glacial acetic acid and dilute to
volume with distilled water.
2. Pipet 1 mL of the stock PRA
solution obtained from the
purification process or from a
commercial source into a 100-
mL volumetric flask and dilute to
volume with distilled water.
3. Transfer a 5-mL aliquot of the
diluted PRA solution from 2, into
a 50-mL volumetric flask. Add 5
mL of 1 M acetate-acetic acid
buffer solution from 1, and dilute
the mixture to volume with
distilled water. Let the mixture
stand for 1 hour.
4. Measure the absorbance of the
above solution at 540 nm with a
spectrophotometer against a
distilled water reference.
Compute the percentage of
nominal concentration of PRA by
%PRA=Ax_K
W (5)
where:
A = measured absorbance of the
final mixture (absorbance units);
W= weight in grams of the PRA dye
used in the assay to prepare 50
mL of stock solution (for
example, 0.100 g of dye was
used to prepare 50 mil of
solution in the purification
procedure; when obtained from
commercial sources, use the
stated concentration to compute
W: for 98% PRA, W = .098 g);
and
K= 21.3 for spectrophotometers
having a spectral bandwidth of
less than 15 nm and a path
length of 1 cm.
[Corrected by 48 FR 17355, April 22,
1983]
8.2.13 Pararosaniline reagent: To a
250-mL volumetric flask, add 20 mL
of stock PRA solution. Add an
additional 0.2 mL of stock solution for
each percentage that the stock assays
below 100 percent. Then add 25 mL
of 3 M phosphoric acid and dilute to
volume with distilled water. The
reagent is stable for at least 9
months. Store away from heat and
light.
9.0 Sampling Procedure.
9.1 General Considerations.
Procedures are described for short-
term sampling (30-minute and 1-hour)
and for long-term sampling (24-hour).
Different combinations of absorbing
reagent volume, sampling rate, and
sampling time can be selected to meet
special needs. For combinations other
than those specifically described, the
conditions must be adjusted so that
linearity is maintained between
absorbance and concentration over
the dynamic range. Absorbing reagent
volumes less than 10 mL are not
recommended. The collection
efficiency is above 98 percent for the
conditions described; however, the
efficiency may be substantially lower
when sampling concentrations below
25fjg S02/m3 (8,9).
[Corrected by 48 FR 17355, April 22,
1983]
-------
Section 2.1.11
Jan. 1983
9.2 30-Minute and 1 -Hour
Sampling.
Place 10 mL of TCM absorbing reagent
in a midget impmger and seal the
impmger with a thin film of silicon
stopcock grease (around the ground
glass joint). Insert the sealed impinger
into the sampling train as shown in
Figure 1, making sure that all connections
between the various components are
leak tight. Greaseless ball joint fittings,
heat shrinkable Teflon® tubing, or
Teflon® tube fittings may be used to
attain leakfree conditions for portions of
the sampling train that come into
contact with air containing SOa. Shield
the absorbing reagent from direct
sunlight by covering the impinger with
aluminum foil or by enclosing the
sampling train in a light-proof box.
Determine the flow rate according to
Section 9.4.2. Collect the sample at
1±0.10 L/min for 30-minute sampling
or 0.500±0.05 L/min for 1 -hour sampling.
Record the exact sampling time in
minutes, as the sample volume will later
be determined using the sampling flow
rate and the sampling time. Record the
atmospheric pressure and temperature.
9.3 24-Hour Sampling.
Place 50 mL of TCM absorbing solution in
a large absorber, close the cap, and, if
needed, apply the heat shrink material
as shown in Figure 3. Verify that the
reagent level is at the 50 mL mark on the
absorber. Insert the sealed absorber
into the sampling train as shown in
Figure 2. At this time verify that the
absorber temperature is controlled to
15±10°C. During sampling, the absor-
ber temperature must be controlled to
prevent decomposition of the collected
complex. From the onset of sampling
until analysis, the absorbing solution
must be protected from direct sunlight.
Determine the flow rate according to
Section 9.4.2. Collect the sample for 24
hours from midnight to midnight at a
flow rate of 0.200±0.020 L/min. A
start/stop timer is helpful for initiating
and stopping sampling and an elapsed
time meter will be useful for determining
the sampling time.
9.4 Flow Measurement.
9.4.1 Calibration: Flow measuring
devices used for the on-site flow
measurements required in 9.4.2 must
be calibrated against a reliable flow or
volume standard such as an NBS
traceable bubble flowmeter or
calibrated wet test meter. Rotameters
or critical orifices used in the
sampling train may be calibrated, if
desired, as a quality control check, but
such calibration shall not replace the
on-site flow measurements required
Tube Caps
Polypropylene
2-Port Tube
Closure
Glass
Impinger
Polypropylene
Tube
Heat Shrink Tape
Etched 50-ml Mark
Absorbing Reagent (TCM)
Figure 3. An absorber /24-hour sample) filled and assembled for shipment.
by 9.4.2. In-line rotameters, if they
are to be calibrated, should be
calibrated in situ, with the appropriate
volume of solution in the absorber.
9.4.2 Determination of flow rate at
sampling site: For short-term samples,
the standard flow rate is determined
at the sampling site at the initiation
and completion of sample collection
with a calibrated flow measuring
device connected to the inlet of the
absorber. For 24-hour samples, the
standard flow rate is determined at
the time the absorber is placed in the
sampling train and again when the
absorber is removed from the train for
shipment to the analytical laboratory
with a calibrated flow measuring
device connected to the inlet of the
sampling train. The flow rate
determination must be made with all
components of the sampling system in
operation (e.g., the absorber
temperature controller and any
sample box heaters must also be
operating). Equation 6 may be used
to determine the standard flow rate
when a calibrated positive
displacement meter is used as the flow
measuring device. Other types of
calibrated flow measuring devices
may also be used to determine the
flow rate at the sampling site provided
that the user applies any appropriate
corrections to devices for which
output is dependent on temperature
or pressure.
Qstd = Qact X
298.16
Pb-(1-RH)PH2o>
Pstd
(Tmeter+273.16)
(6)
where
QSW = flow rate at standard
conditions, std L/min (25 C
and 760 mm»g);
Qaci= flow rate at monitoring site
conditions, L/min;
Pb= barometric pressure at
monitoring site conditions,
mm Hg or kPa;
RH = fractional relative humidity
of the air being measured;
PH20 = barometric pressure of
water at the temperature of
the air in the flow or volume
standard, in the same units
as Pb (for wet volume
standards only, i.e., bubble
-------
Jan. 1983
Section 2.1.11
flowmeter or wet test meter:
for dry standards, i.e., dry
test meter PHZO);
Pstd= standard barometric
pressure, in the same units
as Pb(760 mm Hg or 101
kPa); and
Tmeter = temperature of the air in the
flow or volume standard, °C
(e.g., bubble flowmeter).
[Corrected by 48 FR 17355, April 22,
1983]
If a barometer is not available, the
following equation may be used to
determine the barometric pressure:
Pb = 760 - .076 (H) mm Hg or
Pb = 101 - .01 (H)kPa (7)
where:
H = sampling site elevation above sea
level in meters.
If the initial flow rate (Q,) differs
from the flow rate of the critical
orifice or the flow rate indicated by
the flowmeter in the sampling tram
(Qc) by more than 5 percent as
determined by equation (8), check for
leaks and redetermme Q,.
Q,
(8)
Invalidate the sample if the
difference between the initial (Q,) and
final (Qt) flow rates is more than 5
percent as determined by equation (9):
Q(
9.5 Sample Storage and Shipment.
Remove the impmger or absorber
from the sampling train and stopper
immediately. Verify that the
temperature of the absorber is not
above 25°C. Mark the level of the
solution with a temporary (e.g., grease
pencil) mark. If the sample will not be
analyzed within 12 hours of sampling,
it must be stored at 5°±5°C until
analysis. Analysis must occur within
30 days. If the sample is transported
or shipped for a period exceeding 12
hours, it is recommended that thermal
coolers using eutectic ice packs,
refrigerated shipping containers, etc.,
be used for periods up to 48 hours
(17) Measure the temperature of the
absorber solution when the shipment
is received. Invalidate the sample if
the temperature is above 10°C. Store
the sample at 5° ±5°C until it is
analyzed.
10.0 Analytical Calibration.
10.1 Spectrophotometer Cell
Matching. If unmatched
Spectrophotometer cells are used, an
absorbance correction factor must be
determined as follows
1. Fill all cells with distilled water
and designate the one that has the
lowest absorbance at 548 nm as the
reference. (This reference cell should
be marked as such and continually
used for this purpose throughout all
future analyses.)
2. Zero the Spectrophotometer with
the reference cell
3. Determine the absorbance of the
remaining cells (Ac) in relation to the
reference cell and record these values
for future use. Mark all cells in a
manner that adequately identifies the
correction.
The corrected absorbance during
future analyses using each cell is
determined as follows:
A = Aobs-Ac (10)
where:
A= corrected absorbance,
A0bs= uncorrected absorbance, and
Ac= cell correction.
[Corrected by 48 FR 17355, April 22,
1983]
10.2 Static Calibration Procedure
[Option 1]. Prepare a dilute working
sulfite-TCM solution by diluting 10 mL
of the working sulfite-TCM solution
(Section 8.2.11) to 100 mL with TCM
absorbing reagent. Following the table
below, accurately pipet the indicated
volumes of the sulfite-TCM solutions
into a series of 25-mL volumetric
flasks. Add TCM absorbing reagent as
indicated to bring the volume in each
flask to 10 mL.
Sulfite-TCM
Solution
working
working
working
dilute working
dilute working
Volume of
Sulfite-TCM
Solution, mL
4.0
3.0
2.0
10.0
5.0
0.0
Volume of
TCM, mL
6.0
7.0
8.0
0.0
5.0
10.0
Total
ItgSOz
fapprox.)*
28.8
21.6
14.4
7.2
3.6
0.0
*Based on working sulfite- TCM solution concentration of 7.2/jg SQz/ml; the actual
total /jg SOz must be calculated using equation 11 below
[10.2 table corrected by FR 17355, April 22, 1983}
To each volumetric flask, add 1 mL
0.6% sulfamic acid (Section 8.2.1),
accurately pipet 2 mL 0.2%
formaldehyde solution (Section 8.2.2),
then add 5 mL pararosaniline solution
(Section 8.2.13). Start a laboratory
timer that has been set for 30
minutes. Bring all flasks to volume
with recently boiled and cooled
distilled water and mix thoroughly.
The color must be developed (during
the 30-mmute period) in a temperature
environment in the range of 20° to
30°C, which is controlled to ± 1 °C.
For increased precision, a constant
temperature bath is recommended
during the color development step.
After 30 minutes, determine the
corrected absorbance of each
standard at 548 nm against a distilled
water reference (Section 10.1).
Denote this absorbance as (A).
Distilled water is used in the
reference cell rather than the reagant
blank because of the temperature
sensitivity of the reagent blank.
Calculate the total micrograms SO2 in
each solution:
fJQ SO2 = VicM/so2 x CTCM/SOZ x D
(11)
where:
VTcMso2 = volume of sulfite-TCM
solution used, mL;
CTCM,so2 = concentration of sulfur
dioxide in the working
sulfite-TCM, /ug S02/mL
(from equation 4); and
D= dilution factor (D = 1 for
the working sulfite-TCM
solution; D = 0.1 for the
diluted working sulfite-TCM
solution).
A calibration equation is determined
using the method of linear least
squares (Section 12.1). The total
micrograms SO2 contained in each
solution is the x variable, and the
corrected absorbance (eq. 10)
associated with each solution is the y
variable. For the calibration to be
valid, the slope must be in the range
of 0.030 ±0.002 absorbance unit//ug
SOa, the intercept as determined by
the least squares method must be
equal to or less than 0.170
absorbance unit when the color is
developed at 22°C (add 0.015 to this
0.170 specificaion for each °C above
22°C) and the correlation coefficient
must be greater than 0.998. If these
criteria are not met, it may be the
result of an impure dye and/or an
improperly standardized sulfite-TCM
solution. A calibration factor (B,) is
determined by calculating the
reciprocal of the slope and is
-------
Section 2.1.11
Jan. 1983
subsequently used for calculating the
sample concentration (Section 12.3)
[Corrected by 48 FR 17355, April 22,
1983]
10.3 Dynamic Calibration
Procedures
[Head corrected by 48 FR 17355, April
22, 1983]
(Option 2). Atmospheres containing
accurately known concentrations of
sulfur dioxide are prepared using
permeation devices. In the systems for
generating these atmospheres, the
permeation device emits gaseous SOz
at a known, low, constant rate,
provided the temperature of the
device is held constant (±0.1 °C) and
the device has been accurately
calibrated at the temperature of use.
The SO2 permeating from the device
is carried by a low flow of dry carrier
gas to a mixing chamber where it is
diluted with S02 free air to the
desired concentration and supplied to
a vented manifold. A typical system is
shown schematically in Figure 4 and
this system and other similar systems
have been described m detail by
O'Keeffe and Ortman (19), Scarmgelli,
Frey, and Saltzman (20), and
Scaringelh, O'Keeffe, Rosenberg, and
Bell (21). Permeation devices may be
prepared or purchased and in both
cases must be traceable either to a
National Bureau of Standards (NBS)
Standard Reference Material (SRM
1625, SRM 1626, SRM 1627) or to an
NBS/EPA-approved commercially
available Certified Reference Material
(CRM) CRM's are described in
Reference 22, and a list of CRM
sources is available from the address
shown for Reference 22. A
recommended protocol for certifying a
permeation device to an NBS SRM or
CRM is given in Section 2.0.7 of
Reference 2. Device permeation rates
of 0 2 to 0.4 /ug/min. inert gas flows
of about 50 mL/min, and dilution air
flow rates from 1.1 to 15L/mm
conveniently yield standard
atmospheres in the range of 25 to
600 A/g S02/m3 (0.010 to 0.230 ppm).
10.3.1 Calibration Option 2A (30-
minute and 1-hour samples):
Generate a series of six standard
atmospheres of S02 (e.g., 0, 50, 100,
200, 350, 500, 750 fjg/m3) by
adjusting the dilution flow rates
appropriately. The concentration of
SOz in each atmosphere is calculated
as follows:
Clean Dry Air
Needle Valve
Flow/neter or
Dry Test Meter
Permeation Tube
Thermometer
/
Mixing
Bulb
Purified—I
Air or Drier
" Sampling System Cylinder
Nitrogen
Flowmeter or
Critical Orifice
Waste
Constant
Temperature
Bath
Figure 4. Permeation tube schematic for laboratory use.
C..= P,x IP3
(Qd + OP)
(12)
where:
Ca= concentration of SOz at
standard conditions, /yg/m3,
Pr= permeation rate, //g/min:
Qd= flow rate of dilution air, std
L/min, and
QP= flow rate of carrier gas across
permeation device, std L/min.
[Corrected by 48 FR 17355, April 22,
1983]
Be sure that the total flow rate of
the standard exceeds the flow
demand of the sample train, with the
excess flow vented at atmospheric
pressure. Sample each atmosphere
using similar apparatus as shown in
Figure 1 and under the same
conditions as field sampling (i.e., use
same absorbing reagent volume and
sample same volume of air at an
equivalent flow rate). Due to the
length of the sampling periods
required, this method is not
recommended for 24-hour sampling.
At the completion of sampling,
quantitatively transfer the contents of
each impinger to one of a series of
25-mL volumetric flasks (if 10 ml_ of
absorbing solution was used) using
small amounts of distilled water for
rinse (< 5mL). If >10 mL of absorbing
solution was used, bring the absorber
solution in each impinger to orginal
volume with distilled H2O and pipet
10-mL portions from each impinger
into a series of 25-mL volumetric
flasks. If the color development steps
are not to be started within 12 hours
of sampling, store the solutions at 5°
± 5°C. Calculate the total micrograms
SOz in each solution as follows:
//gSna-CaxQ8xtxVax10'3 (13)
Vb
where:
Ca= concentration of SOj in the
standard atmosphere, //g/m3;
Q,= sampling flow rate, std
L/min;
t= sampling time, min;
Va= volume of absorbing solution
used for color development (10
mL); and
Vb = volume of absorbing solution
used for sampling, mL.
Add the remaining reagents for
color development in the same
manner as in Section 10.2 for static
solutions. Calculate a calibration
equation and a calibration factor (Ba)
according to Section 10.2, adhering to
all the specified criteria.
10.3.2 Calibration option 2B (24-
hour samples): Generate a standard
atmosphere containing approximately
1,050/yg SOz/m3 and calculate the
exact concentration according to
equation 12. Set up a series of six
absorbers according to Figure 2 and
connect to a common manifold for
sampling the standard atmosphere. Be
-------
Jan. 1983
Section 2.1.11
sure that the total flow rate of the
standard exceeds the flow demand at
the sample manifold, with the excess
flow vented at atmospheric pressure.
The absorbers are then allowed to
sample the atmosphere for varying
time periods to yield solutions
containing 0, 0.2, 0.6, 1.0, 1.4, 1.8,
and 2.2 /ug SOa/mL solution. The
sampling times required to attain
these solution concentrations are
calculated as follows:
t =.
VbxC,
(14)
CaxQ,x10"J
where:
t= sampling time, min;
Vb= volume of absorbing solution
used for sampling (50 ml);
Cs= desired concentration of SOi
in the absorbing solution,
A/g/mL;
Ca= concentration of the standard
atmosphere calculated
according to equation 12,
/ug/m3; and
da- sampling flow rate, std
L/min.
[Corrected by 48 FR 17335, April 22,
1983]
At the completion of sampling, bring
the absorber solutions to original
volume with distilled water. Pipet a
10-mL portion from each absorber
into one of a series of 25-mL
volumetric flasks. If the color
development steps are not to be
started within 12 hours of sampling,
store the solutions at 5° ± 5°C. Add
the remaining reagents for color
development in the same manner as
in Section 10.2 for static solutions.
Calculate the total /ug SO2 in each
standard as follows:
[Corrrected by 48 FR 17335, April 22,
1983]
//gSng = CaxQ,xtxVax10'3 (15)
Vb
where:
Va= volume of absorbing solution
used for color development (10
mL).
All other parameters are defined in
equation 14.
Calculate a calibration equation and
a calibration factor (Bt) according to
Section 10.2 adhering to all the
specified criteria.
11.0 Sample Preparation
and Analysis
11.1 Sample Preparation. Remove
the samples from the shipping
container. If the shipment period
exceeded 12 hours from the completion
of sampling, verify that the
temperature is below 10°C. Also,
compare the solution level to the
temporary level mark on the absorber.
If either the temperature is above
10°C or there was significant loss
(more than 10 mL) of the sample
during shipping, make an appropriate
notation in the record and invalidate
the sample. Prepare the samples for
analysis as follows:
1. For 30-mmute or 1-hour
samples: Quantitatively transfer
the entire 10 ml amount of
absorbing solution to a 25-mL
volumetric flask and rinse with a
small amount (<5 mL) of distilled
water.
2. For 24-hour samples: If the
volume of the sample is less than
the original 50-mL volume
(permanent mark on the
absorber), adjust the volume back
to the original volume with
distilled water to compensate for
water lost to evaporation during
sampling. If the final volume is
greater than the original volume,
the volume must be measured
using a graduated cylinder. To
analyze, pipet 10 mL of the
solution into a 25-mL volumetric
flask,
11.2 Sample Analysis. For each set
of determinations, prepare a reagent
blank by adding 10 mL TCM absorbing
solution to a 25-mL volumetric flask,
and two control standards containing
approximately 5 and 15 /ug SC>2,
respectively. The control standards are
prepared according to Section 10.2
or 10.3. The analysis is carried out as
follows.
1. Allow the sample to stand 20
minutes after the completion of
sampling to allow any ozone to
decompose (if applicable).
2. To each 25-mL volumetric flask
containing reagent blank,
sample, or control standard, add
1 mL of 0.6% sulfamic acid
(Section 8.2.1) and allow to react
for 10 min.
3. Accurately pipet 2 mL of 0.2%
formaldehyde solution (Section
8.2.2) and then 5 mL of
pararosaniline solution (Section
8.2.13) into each flask. Start a
laboratory timer set at 30
minutes.
4. Bring each flask to volume with
recently boiled and cooled
distilled water and mix
thoroughly.
5. During the 30 minutes, the
solutions must be in a
temperature controlled
environment in the range of 20°
to 30°C maintained to ± 1°C.
This temperature must also be
within 1°C of that used during
calibration.
6. After 30 minutes and before 60
minutes, determine the corrected
absorbances (equation 10) of
each solution at 548 nm using 1-
cm optical path length cells
against a distilled water
reference (Section 10.1).
(Distilled water is used as a
reference instead of the reagent
blank because of the sensitivity
of the reagent blank to
temperature.}
7. Do not allow the colored solution
to stand in the cells because a
film may be deposited. Clean the
cells with isopropyl alcohol after
use.
8. The reagent blank must be
within 0.03 absorbance units of
the intercept of the calibration
equation determined in Section
10.
11.3 Absorbance range. If the
absorbance of the sample solution
ranges between 1.0 and 2.0, the
sample can be diluted 1:1 with a
portion of the reagent blank and the
absorbance redetermined within 5
minutes. Solutions with higher
absorbances can be diluted up to
sixfold with the reagent blank in order
to obtain scale readings of less than
1.0 absorbance unit. However, it is
recommended that a smaller portion
«10 mL) of the original sample be
reanalyzed (if possible) if the sample
requires a dilution greater than 1:1.
11.4 Reagent disposal. All reagents
containing mercury compounds must
be stored and disposed of using one
of the procedures contained in
Section 13. Until disposal, the
discarded solutions can be stored in
closed glass containers and should be
left in a fume hood.
12.0 Calculations
12.1 Calibration Slope. Intercept,
and Correlation Coefficient. The
method of least squares is used to
calculate a calibration equation in the
form of:
y = mx + b (16)
where.
y = corrected absorbance,
m=slope, absorbance unit//ug SOz
x = micrograms of SOz
b= y intercept (absorbance units).
[Corrected by 48 FR 17355, April 22,
1983]
The slope (m), intercept (b), and
correlation coefficient (r) are
calculated as follows:
-------
Section 2.1.11
10
Jan. 1983
m = nlxy - (Ix) (Iy)
nix2 - (Ix)2
(17)
(18)
DATA FORM
(For hand calculations)
r =
- Ixly/n) (19)
Iy2 - (Iy)2/n
where n is the number of calibration
points.
A data form (Figure 5) is supplied
for easily organizing calibration data
when the slope, intercept, and
correlation coefficient are calculated
by hand.
12.2 Total Sample Volume. Determine
the sampling volume at standard
conditions as follows:
(20)
where:
Vstd= sampling volume in std L,
Q,= standard flow rate determined
at the initiation of sampling in
std L/min,
Qf= standard flow rate determined
at the completion of sampling
in std L/min, and
t= total sampling time, mm.
[Corrected by 48 FR 17355, April 22,
1983]
12.3 Sulfur Dioxide Concentration.
Calculate and report the concentration
of each sample as follows:
= (A-A0)(B,)(103)vVb
V,ta Va
(21)
where:
A= corrected absorbance of the
sample solution, from equation
(10);
A0= corrected absorbance of the
reagent blank, using equation
(10);
Bx = calibration factor equal to Bs
B9 or Bi depending on the
calibration procedure used, the
reciprocal of the slope of the
calibration equation;
Va= volume of absorber solution
analyzed, mL;
Vb= total volume of solution in
absorber (see 11.1-2), mL; and
V,td= standard air volume sampled,
std L (from Section 12.2).
Calibration
point no.
1
2
3
4 .
5
6
Micro -
grams
SO,
M
Absor-
bance
units
M
x2
*Y
y2
Zxy = .
n =
coordmates )
. (number of pairs of
[Data Form corrected by 48 FR 17355,
April 22, 1983]
Figure 5. Data form for hand calculations.
12.4 Control Standards. Calculate
the analyzed micrograms of SOa in
each control standard as follows:
Ca = (A - Ao) x Bx (22)
where:
Ca= analayzed fjg SOa in each control
standard,
A= corrected absorbance of the
control standard, and
A0= corrected absorbance of the
reagent blank.
The difference between the true
and analyzed values of the control
standards must not be greater than 1
fjg. If the difference is greater than 1
fjg, the source of the discrepancy
must be identified and corrected.
12.5 Conversion of fjg/m3 to ppm
(v/v). If desired, the concentration of
sulfur dioxide at reference conditions
can be converted to ppm SOz (v/v) as
follows:
ppm SO2=A<9_S02x3.82x10~4 <23>
m3
[Corrected by 48 FR 17355, April 22,
1983]
13.0 Disposal of Mercury-
Containing Solutions
13.1 The TCM absorbing solution
and any reagents containing mercury
compounds must be treated and
disposed of by one of the methods
discussed below. Both methods
remove greater than 99.99 percent of
the mercury.
13.2 Method for Forming an
Amalgam.
1. Place the waste solution in an
uncapped vessel in a hood.
2. For each liter of waste solution,
add approximately 10 g of sodium
carbonate until neutralization has
occurred (NaOH may have to be used).
3. Following neutralization, add 10
g of granular zinc or magnesium.
4. Stir the solution in a hood for 24
hours. Caution must be exercised as
hydrogen gas is evolved by this
treatment process.
5. After 24 hours, allow the
solution to stand without stirring to
allow the mercury amalgam (solid
black material) to settle to the bottom
of the waste receptacle.
[Corrected by 48 FR 17355, April 22,
1983]
6. Upon settling, decant and discard
the supernatant liquid.
7. Quantitatively transfer the solid
material to a container and allow to
dry.
8. The solid material can be sent to
a mercury reclaiming plant. It must
not be discarded.
13.3 Method Using Aluminum Foil
Strips.
1. Place the waste solution in an
uncapped vessel in a hood.
2. For each liter of waste solution,
add approximately 10 g of aluminum
foil strips. If all the aluminum is
consumed and no gas is evolved, add
an additional 10 g of foil. Repeat until
the foil is no longer consumed and
allow the gas to evolve for 24 hours.
3. Decant the supernatant liquid
and discard.
4. Transfer the elemental mercury
that has settled to the bottom of the
vessel to a storage container.
5. The mercury can be sent to a
mercury reclaiming plant. It must not
be discarded.
14.0 References for SOz
Method.
1. Quality Assurance Handbook for
Air Pollution Measurement Systems,
Volume I, Principles. EPA-600/9-76-
005, U.S. Environmental Protection
Agency, Research Triangle Park, North
Carolina 27711, 1976.
2. Quality Assurance Handbook for
Air Pollution Measurement Systems,
Volume II, Ambient Air Specific
Methods. EPA-600/4-77-027a, U.S.
Environmental Protection Agency,
Research Triangle Park, North
Carolina 27711, 1977.
3. Dasqupta, P.K., and K.B.
DeCesare. Stability of Sulfur Dioxide
in Formaldehyde and Its Anomalous
Behavior in Tetrachloromercurate (II).
Submitted for publication in
Atmosphere Environment, 1982.
4. West, P.W., and G.C. Gaeke.
Fixation of Sulfur Dioxide as
Disulfitomercurate (II) and Subsequent
-------
Jan. 1983
11
Section 2.1.11
Colonmetric Estimation Anal. Chem.,
28.1816, 1956.
5. Ephraim, F Inorganic Chemistry.
P C.L Thorne and E.R. Roberts, Eds.,
5th Edition, Interscience, 1948, p.
562.
6. Lyles, G.R., F.B. Dowling, and
VJ. Blanchard. Quantitative
Determination of Formaldehyde in the
Parts Per Hundred Million
Concentration Level J. Air. Poll
Cont Assoc., Vol 15(106), 1965.
7. McKee, H.C., R.E. Childers, and
0. Saenz, Jr. Collaborative Study of
Reference Method for Determination
of Sulfur Dioxide in the Atmosphere
(Pararosamline Method). EPA-APTD-
0903, U.S. Environmental Protection
Agency, Research Triangle Park, North
Carolina 27711, September 1971
8. Drone, P., J.B. Evans, and C.M.
Noyes. Tracer Techniques in Sulfur—
Air Pollution Studies Apparatus and
Studies of Sulfur Dioxide Colonmetric
and Conductometric Methods. Anal.
Chem., 37: 1104, 1965.
9. Bostrom, C.E. The Absorption of
Sulfur Dioxide at Low Concentrations
(pphm) Studied by an Isotopic Tracer
Method, Intern. J. Air Water Poll.,
9:333, 1965.
10. Scarmgelli, F.P, B.E. Saltzman,
and S.A. Frey. Spectrophotometric
Determination of Atmospheric Sulfur
Dioxide. Anal. Chem., 39 1709, 1967
11. Pate, J.B., B E. Ammons, G.A.
Swanson, and J.P. Lodge, Jr. Nitrite
Interference in Spectrophotometric
Determination of Atmospheric Sulfur
Dioxide. Anal. Chem., 37:942, 1965.
12. Zurlo, N., and A.M Griffini
Measurement of the Sulfur Dioxide
Content of the Air in the Presence of
Oxides of Nitrogen and Heavy Metals.
Medicina Lavoro, 53330, 1962
13. Rehme, K.A., and F P
Scaringelh. Effect of Ammonia on the
Spectrophotometric Determination of
Atmospheric Concentrations of Sulfur
Dioxide Anal. Chem., 47:2474, 1975.
14. McCoy, R.A., D.E. Camann, and
H.C. McKee. Collaborative Study of
Reference Method for Determination
of Sulfur Dioxide in the Atmosphere
(Pararosamline Method) (24-Hour
Sampling). EPA-650/4-74-027, U.S.
Environmental Protection Agency,
Research Triangle Park, North
Carolina 27711, December 1973.
15. Fuerst, R.G. Improved
Temperature Stability of Sulfur Dioxide
Samples Collected by the Federal
Reference Method. EPA-600/4-78-
018, U.S. Environmental Protection
Agency, Research Triangle Park, North
Carolina 27711, April 1978.
16. Scaringelli, F.P., L Elfers, D.
Norris, and S. Hochheiser. Enhanced
Stability of Sulfur Dioxide in Solution.
Anal. Chem., 42 1818, 1970.
17. Martin, B.E. Sulfur Dioxide
Bubbler Temperature Study. EPA-
600/4-77-040, U.S. Environmental
Protection Agency, Research Triangle
Park, North Carolina 27711, August
1977.
18. American Society for Testing
and Materials. ASTM Standards,
Water; Atmospheric Analysis. Part 23,
Philadelphia, Pennsylvania, October
1968, p. 226.
19 O'Keeffe, A.E., and G.C.
Ortman Primary Standards for Trace
Gas Analysis Anal. Chem., 38: 760,
1966.
20. Scaringelli, F.P., S.A. Frey, and
B.E. Saltzman. Evaluation of Teflon
Permeation Tubes for Use with Sulfur
Dioxide. Amer. Ind. Hygiene Assoc.
J., 28:260, 1967.
21. Scaringelli, F.P., A.E. O'Keeffe,
E. Rosenberg, and J.P. Bell,
Preparation of Known Concentrations
of Gases and Vapors With Permeation
Devices Calibrated Gravimetrically,
Anal. Chem., 42:871, 1970.
22. A Procedure for Establishing
Traceability of Gas Mixtures to Certain
National Bureau of Standards
Standard Reference Materials. EPA-
600/7-81-010. U.S. Environmental
Protection Agency, Environmental
Monitoring Systems Laboratory (MD-
77), Research Triangle Park, North
Carolina 27711, January 1981.
-------
Jan. 1983
Section 2.1.12
12.0 References
1. U.S. Environmental Protection
Agency. Collaborative Study of
Reference Method for Determination
of Sulfur Dioxide in the Atmosphere
(Pararosaniline Method) (24-hour
sampling). EPA-650/4-74-027,
December 1973.
2. McKee, H.C., et al. Collaborative
Study of Reference Method for the
Determination of Suspended
Particulates in the Atmosphere (High
Volume Method). Southwest Research
Institute. Contract EPA 70-40, SWRI
Project 21-2811. San Antonio, Texas
June 1971.
3. Smith, F., and A.C. Nelson, Jr.
Guidelines for Development of a
Quality Assurance Program,
Reference Method for the
Determination of Sulfur Dioxide in the
Atmosphere (Pararosaniline Method).
EPA-R4-73-028d, August 1973.
4. U.S. Environmental Protection
Agency. The Monitoring and Field
Activity of the National Air
Surveillance Network. Standard
Operating Procedures for EPA, Region
IV. August 5, 1975.
5. Glasstone, S., and D. Lewis.
Elements of Physical Chemistry. Van
Nostrand Press, 1962. pp 657-658.
6. Fuerst, R.G., et al. Effect of
Temperature on Stability of Sulfur
Dioxide Samples Collected by the
Federal Reference Method.
Environmental Monitoring Series.
EPA-600/4-76-024, May 1976.
7. U.S. Environmental Protection
Agency. Quality Assurance Handbook
for Air Pollution Measurement
Systems - Volume I, Principles. EPA-
600/9-76-005, March 1976
8. Scaringelli, F.P., et al.
Spectrophotometric Determination of
Atmospheric Sulfur Dioxide. Analytical
Chemistry, 39, p. 1709, 1967.
9. Bromberg, S.M., R.L. Lampe, and
B.I. Bennett. Summary of Audit
Performance: Measurement of SOa,
NO2, CO, Sulfate, Nitrate, Lead, Hi-Vol
Flow Rate - 1977 EPA-600/4-79-
014, February 1979.
10. Bromberg, S.M., R.L. Lampe,
and B.I. Bennett. Summary of Audit
Performance: Measurement of SO2,
NO2, CO, Sulfate, Nitrate, Lead, Hi-Vol
Flow Rate - 1978. Report m
preparation by U.S. Environmental
Protection Agency, Environmental
Monitoring Systems Laboratory (MD-
77), Research Triangle Park, N.C.
11. U.S. Department of Commerce.
NBS Standard Reference Materials
Catalog. NBS Special Publication 260,
1981-83 Edition. National Bureau of
Standards. Washington, D.C.
November 1981.
-------
Jan. 1983
Section 2.1.13
13.0 Data Forms
Blank data forms are provided on
the following pages for the
convenience of the Handbook user
The customary descriptive title is
centered at the top of the page;
however, the usual section-page
documentation in the top right-hand
corner of each page has been
replaced with a number in the lower
right-hand corner that will enable the
user to identify and refer to a similar
filled-in form in a text section. For
example, Form SOa-1.1 indicates that
the form is Figure 1.1 of the SOa
method description. Any future
revisions of these forms can be
documented as 1.1 A, 1 1B, etc. The
following data forms are included:
Form
Title
1.1
2.2
2.4
2.6
2.8
2.11
4.10
5.1
5.3
5.4A
5.4B
6.1
6.2
8.1
8.2
Procurement Log
Wet Test Meter Calibration Log
Soap-Bubble Meter Calibration Log
Mass-Flow Meter Calibration Log
Rotameter Calibration Data Form
Timer Calibration Log
Gas Bubbler Data Record
S02 Calibration Data Sheet
Data Form for Hand Calculation
Laboratory Data Log (Front)
Laboratory Data Log (Back)
SAROAD Daily Data Form
SAROAD Hourly Data Form
X-and-R Chart
Checklist for Use by Auditor for S02 Method
-------
Section 2.1.13
Jan. 1983
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Jan. 1983
Section 2.1.13
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Section 2.1.13
Jan. 1983
Soap Bubble Meter Calibration Log
Meter ser/f>/ number r>&tf>
Displacement volume* Calibrated hy ......
Test
number
Water
temper-
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°C
Initial
weight of
flask (WtJ,
9
Final
weight of
water and
flask (Wtj,
g
Displacement
volume fVo}."
ml
Remarks
"V = displacement volume stated by manufacturer = _ ml
Vd = Wt< ~ Wt> = _ = _ / D, = _ g/ml (Table 2 2).
D,
p", =
Va
., not to exceed ±1%
Quality Assurance Handbook SOi-2.4
-------
Jan. 1983
Section 2.1.13
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Section 2.1.13
Jan. 1983
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Jan. 1983
Section 2.1.13
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Section 2.1.13
Jan. 1983
Station Location
City & State
Site & Address
Project
Pollutant
Sampler ID No.
Gas Bubbler Data Record
. Site No.
Type of Flow Measuring Device .
Identification Number of Device
Initial Flow
. Sample No.
Final Flow
Vacuum Reading Start
Vacuum Reading End .
Start Samp/ing
mo
Stop Sampling
mo
Elapsed Time Start
Elapsed Time Stop _
Nominal Flow Rate
Open
Clamp
day
day
% Difference
Average
Average sample temperature .
Ambient temperature: Start _
Barometric pressure: Start _
REMARKS:
Average
. °C Relative humidity
°C, Stop
nm Hg, Stop
.°C. Average °C
_ mm Hg. A verage mm Hg
Meteorological conditions for use when anomaly occurs.
WIND calm light gusty
clear .
.hazy
VISIBILITY _
SKY clear scattered overcast
HUMIDITY dry moderate humid rainy
TEMP °F .
.<20.
. 20-40 .
.41-60 .
.61-80 .
>80
Sample collected within
guidelines given below.
Signature
Guidelines
Proper flow rate — J/2-h samples - 900-1100 cm3/min
— 1-h samples - 450-550 cm3/mm
— 24-h samples - 180-220 cm3/mm
24-h sampling — 23 h < sampling time < 25 h
— >35 ml of absorbing reagent remain after samp/ing
— sampler timer accuracy ±15 min/24 h
Quality Assurance Handbook SOs-4. JO
-------
Jan. 1983
Section 2.1.13
Date
Instrument I.D.
SO2 Calibration Data Sheet
. mm, Temperature
Color Development Time
Wavelength nm /jg SOz/ml (Working su/fite-TCM solution)
Analyst
. °C
I/TCM SO2
0
5
10
2
3
4
D
1
0 1
0 1
1
1
1
ugSOi
0.0
Absorbance
fjg SC>2 = VTCM S02 x CTCM soa X D
I^TCMSO= volume of sulfite-TCM solution used, ml,
CTCM so2 = concentration of SOz in the working sulfite- TCM solution, ug SO*/ml. and
D - dilution factor
Regression analysis results:
Measured
Slope
Intercept.
Criteria
0 030+0.002 absorbance units/tig SOz
<0 170 at 22°C (add 0.015 per °C above 22°C)
Correlation coefficient.
1
Calibration factor B, - slope = .
. X3.998
— tig SO*/absorbance unit
Quality Assurance Handbook SOt-5.1
-------
Section 2.1.13
10
Jan. 1983
Calibration
point
number
Micrograms
SOz
M
DA TA FORM
For Hand Calculations
Absorbance
units
M
4
5
Ix =
Ix*
(number of calibration points)
Calibration Slope, Intercept, and Correlation Coefficient The method of least squares is used to calculate a calibration equation in the form
of:
where
y - corrected absorbance,
m - slope, absorbance units/'(jg SOz,
x = micrograms of SOi.
b = y intercept (absorbance units)
y = mx + b
Equation 1
The slope (ml. intercept (b), and correlation coefficient (r) are calculated as follows:
nix* - (
b = ly - ml;
n
r = Imflx
V ^
^ ( )( )-( y
,=f } - ( )( ) =
( )
Z 1 6 -/ ( j I { ) ( ) (
-fiyr'/n \ ' ) - f ' Y ( )
} ( )]
Quality Assurance Handbook SOi-5.3
-------
Jan. 1983
11
Section 21,13
CO
Q
CO
O
n
absorber, ml
D = dilution factor /if any) required to
reduce samp/e aosoroance rjeiow i
Handled in Accordance with Guidelines on
Reverse Side of This Form
<
'*
:
b
b
5
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-------
Section 2.1.13
12
Jan. 1983
Laboratory Data Log (Backside)
Preparation and Calibration
Sample Analysis
Colorimetric analysis blank
within ±O.03 absorbance
calibration intercept; control
sample absorbance within
±1 ug SOi of actual value
Calibration curve for ab-
sorbance vs. ug SOz/m3
slope between 0.03 ±0.002
absorbance units/ug SO*
intercept
-------
Jan. 1983
13
Saroad Daily Data Form
Section 2.1.13
24-Hour or Greater Sampling Interval
nn
7 Agency
State
Area
Site
City Name
Site Address
23456789 10
Agency Project Time Year
Month
L
Project
Time Interval
11
12 13 14 15 16 17 18
Name
PARAMETER
Code
I
I
23 24 25 26
27
28 29 30 31
32
Name
PARAMETER
Code
37 38 39
42
40 41
43 44 45 46
Name
PARAMETER
Code
51 52 53 54 55
56
57
58 59
60
Name
PARAMETER
Code
65 66 67 68 69
70
71 72 73 74
DP-
43210
43210
43210 4 3 2 1 U
Quality Assurance Handbook SOi-6.1
-------
Section 2.1.13
14
Jan. 1983
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15
Section 2.1.13
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-------
Section 2.1.13 16 Jan. 1983
Checklist tor Use by Auditor for SOi Method
} What type of manual sampler is used for SOz collection?
(a) RAC (b) 5-port (c) 2-port (d) other
2 Is a straight tube impinger used in the polypropylene sampling tube?.
3. Is sample probe made of accepted material? Teflon1^ Glass .
4 Is the probe (and manifold) located to prevent moisture condensation when sampling in humid conditions? .
5 What method of analysis is used? Is a copy available? (Method should be from 40
CFR 50. July 1. 1982, as amended 47 FR 54896, December 6. 1982 and 48 FR 17355. April 22. 1983
6 What quality of reagents is used to make up the chemicals for the SOz analysis?
(They should be reagent grade or better
7 Is the sampling tram routinely checked for leaks?
How often? (a) Once a week (b) Once a month (c) Once a quarter (d) other .
8. What calibration check procedure is used for flow measuring device used in the field?
Is a written copy available?
9 Are sampling flow rates determined before and after each sampling period? Is there an established procedure for
discarding needles that are not within flow rate limits initially? If so, what are the limits? (Any
needle outside of 180 to 200 cm3/mm should be discarded for 24-h samples). Is the absorbing solution maintained at 15° ±10°C?
Are samples voided? Do initial and final flow rates agree within ±5%? (Void sample if they are
not)
10. Have calibration curves been made, and are they available? Is the calibration history of the analyses in a bound (or
other type) of notebook, and is it readily available?
I All laboratories must keep a bound notebook as a permanent record of the calibration history that indicates when the curves were
made and what points were used to make them)
11. Are collected samples shipped from the field to the laboratory in containers that prevent crushing, spilling, etc., and maintained at a
temperature of 5°± 5°C?
12 How many days were there between sampling and analysis? days (Commonly it is approximately 12 days; less than 12
is very good, but more than 12 may cause problems in analysis)
13. Are samples stored in the dark until they are analyzed? At what temperature are the samples stored? °C
14. What calculations were performed to obtain the final SOi concentration?
(If possible, show the completed calculations J
15. How were discrepancies in the data treated?
16. Are the data reported quarterly? // not, how often?
(There should be a format for taking care of data discrepancies.)
Quality Assurance Handbook SOi-8 2
-------
Jan. 1983
Section 2.2.0
United States
Environmental Protection
Agency
Environmental Monitoring Systems
Laboratory
Research Triangle Park NC 27711
Research and Development
EPA-600/4-77-027a
AEPA
Test Method
Section 2.2
Reference Method for the
Determination of Suspended
Particulates
in the Atmosphere
(High-Volume Method)
Outline
Section
Summary
Method QA Highlights
Method Description
1. Procurement of Equipment
and Supplies
2. Calibration of Equipment
3. Filter Selection and
Preparation
4. Sampling Procedure
5. Analysis of Samples
6. Calculations and Data
Reporting
7. Maintenance
8. Auditing Procedure
9. Assessment of Monitoring
Data for Precision and
Accuracy
10. Recommended Standards for
Establishing Traceability
11. Reference Method
12. References
13. Data Forms
Summary
Ambient air drawn into a covered
housing and through a filter by a
high-flow-rate blower at 1.1 to 1.7
mVmin (39 to 60 ftVmin) allows total
Number of
Documentation Pages
2.2 1
2.2 1
2.2.1
2.2.2
2.2.3
2.2.4
2.2.5
2.2.6
2.2.7
2.2.8
2.2.9
2.2.10
2.2.11
2.2.12
2.2.13
13
4
8
1
2
2
4
1
1
10
1
10
suspended particulates (TSP) in sizes
up to 25 to 50 fjm (aerodynamic
diameter) to collect on the filter
surface. When operated within this
range, the high-volume sampler is
-------
Section 2.2.0
Jan. 1983
capable of collecting TSP samples for
24-hour TSP concentrations ranging
from 2 to TSO/yg/std m1 The mass
concentration (/jg/m3)* in ambient air
is computed by measuring both the
mass of TSP collected and the
(standard) volume of air sampled
This method provides a
measurement of the mass
concentration of total suspended
paniculate matter (TSP) in ambient air
for determination of compliance with
the primary and secondary National
Ambient Air Quality Standards for
Paniculate Matter as specified in
§50 6 and §50 7 of the Code of
Federal Regulations, Title 40 The
measurement process ts
nondestructive, and the size of the
sample collected is usually adequate
for subsequent chemical analysis
Based on collaborative testing, the
relative standard deviation (coefficient
of variation) for single analyst
precision (repeatability) of the method
is 3 0 percent. The correspondrng
value for interlaboratory precision
(reproducibility) is 3 7 percent
The absolute accuracy of the
method is undefined because of the
complex nature of atmospheric
paniculate matter and the difficulty in
determining the "true" paniculate
matter concentration
This reference method appears in
Title 40 of the Code of Federal
Regulations, Part 50, Appendix B (as
amended on December 6, 1982, (47
FR 5491 2) A complete copy of the
Reference Method is reproduced in
Section 2211
Method QA Highlights
In this quality assurance document
for the TSP Reference Method (high-
volume sampler method), the
procedures are designed to serve as
guidelines for the development of
agency quality assurance programs
Because recordkeepmg is a critical
part of quality assurance activities,
several data forms are included to aid
in the documentation of necessary
data The blank data forms (Section
2.2 13) may be used as they are, or
they may serve as guidelines for
preparing forms more appropriate to
the individual agency, partially filled-
in forms are interspersed throughout
the text to illustrate their uses
Activity matrices at the end of
pertinent sections provide a review of
"Although TSP is measured in micrograms per
standard cubic meter, the ' standard' is
commonly omitted when reporting TSP
measurements, by convention, /jg/m3 for TSP is
understood to mean fjg/sldi m3
the material covered in the text
sections The material covered in this
section for the TSP method is briefly
summarized here.
1. Procurement of Equipment
Section 2 2.1 describes the selection
of equipment and the recommended
procurement and calibration checks
for the equipment. It also identifies
the sections of this part of the
Handbook that pertain to specific
equipment and supplies. Figure 1.1
provides an example of a permanent
procurement record.
2. Calibration of Equipment Section
2.2.2 provides detailed calibration
procedures for the analytical balance,
the relative humidity indicator, the
elapsed-time meter, the flow-rate
transfer standard, and the high-
volume sampler. This section can be
removed (along with the
corresponding sections for the other
methods of this volume of the
Handbook) to serve as a calibration
handbook. Table 2 2 at the end of the
Section summarizes the acceptance
limits for equipment calibration.
3. Filter Selection and Preparation
Section 2.2.3 presents important
considerations for the selection,
identification, equilibration, weighing
check, and handling of filters. The
spectro-quality grade filter is
recommended for use when additional
chemical analyses are anticipated.
4. Sampling Procedure Section 2.2.4
details procedures for filter
installation, performance of
operational checks, sample handling,
and data documentation. Several
photographs are provided to clarify
the installation procedure. Complete
documentation of background
information during the sampling is
one of several quality assurance
activities iftat are important to future
data validation; particularly important
are any unusual conditions existing
during collection of the sample. Any
such conditions should be noted.
5. Analysis of Samples Section 2.2.5
briefly describes verification of data
from the field, sample inspection,
filter equilibration, and the gravimetric
analysis procedure. The analytical
balance must be checked. The filter
must be equilibrated in a controlled
environment.
6. Calculation and Data Reporting
Section 2.2 6 describes those
activities pertaining to data
calculations and reporting. The final
data review, the data edit or
validation, and the use of standardized
reporting procedures are all important
parts of a quality assurance program.
independent checks of the data and
calculations are recommended to
ensure that the reported data are both
accurate and precise.
7. Maintenance Section 2.2.7
recommends periodic maintenance
schedules to ensure that the
equipment is capable of performing as
specified.
8. Assessment of Data for Accuracy
and Precision Sections 2.2.8 and
2.2.9 describe the assessment of the
data for accuracy and precision,
respectively. Independent audit
activities provide accuracy checks of
flow rate measurements, filter
weighings, and data processing.
The precision check is performed by
using collocated samplers. The
expected agreement between two
collocated samplers is ±15%.
9. Reference Information Section
2.2.10 discusses the traceability of
measurements to established
standards of higher accuracy, a
necessary prerequisite for obtaining
accurate data.
Sections 2.2.11 and 2.2.12 contain
the Reference Method and pertinent
references.
Section 2.2.13 provides blank data
forms for the convenience of the user.
-------
Jan. 1983
Section 2.2.1
1.0 Procurement of Equipment and Supplies
Specifications for equipment and
supplies for monitoring ambient air for
total suspended particulates (TSP) are
provided in the Reference Method, as
reproduced in Section 2.2.11.
Upon receipt of the sampling
equipment and supplies, appropriate
procurement checks should be
conducted to determine their
acceptability, and their acceptability
or rejection should be recorded in a
procurement log. Figure 1.1 is an
example of such a log, and Section
2.2.13 provides a blank copy for the
Handbook user. This log will serve as
a permanent record for future
procurements and for any fiscal
projections for future programs. It will
also help to provide continuity of
equipment and supplies Table 1-1
provides a matrix of the activities
involved in the procurement of
equipment and supplies.
The following list of equipment,
apparatus, and supplies provides a
reference to sections and subsections
within this part of the Handbook to
guide the user to specific checkout
procedures. Here and throughout the
balance of the text, "section" refers to
the primary divisions of Section 2.2,
"subsection" refers to the
subdivisions within these sections
Item
Section
Subsection
Analytical balance
Relative humidity indicator
Elapsed-time meter
Timer
Flow rate transfer standard
Sampler
Filter
Sampler motor
Faceplate gasket
Rotameter
Sampling head
Motor gasket
Flow transducer and recorder
2.2.2
2.2.2
2.2.2
2.2.2
2.2.2
2.2.2
2.2.3
2.2.7
2.2.7
2.2.7
2.2.7
2.2.7
22.7
2.1
2.2
2.3
2.4
2.5
2.6
3.1, 3.3
7.1
7.2
7.3
7.4
7.5
7.6
Table 1.1 Activity Matrix for Procurement of Equipment and Supplies
Equipment
Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
Analytical balance
Elapsed-time meter
Timer
Orifice calibration unit (flow
transfer standard)
Sampler
Indicated weight -
standard weight ±0.0005
g for three to five standard
weights over sample filter
weight range
24 h ±2 min
24 h ±30 min
Calibration flow rate -
actual flow rate ±2%
Sampler complete; no
evidence of damage; flow
~ 1.1 - 1.7 m3/min
On receipt, check against
weights of known
accuracy.
On receipt, check against
standard timepiece of
known accuracy.
On receipt, check against
elapsed-time meter.
On receipt, check against
flow-rate primary standard.
On receipt, observe visually
and check operation of all
components.
Request recalibration
by manufacturer/supplier.
Adjust or reject.
Adjust or reject.
Adopt new calibration
curve if no evidence of
damage; reject if damage
is evident.
Reject or repair.
Relative humidity indicator
Indicator reading -
psychrometer reading ±6%
On receipt, compare with
reading of a wet bulb/dry
bulb psychrometer.
Adjust or replace to attain
acceptance limits.
-------
Section 2.2.1
Jan. 1983
Item description
Hl-VOLW>H%
H/'VdL.3R05HSE3
Quantity
/z
/oo
Purchase
order
number
/7«-
m*-
Vendor
dw'j-HEW-
$EHL METAL
Date
Ordered
£-/-75
b-l-15
Received
6 -/0-75
6-/0-Z5
Cost
Z.I
&
Dispo-
sition
ACC.
Ace.
Comments
Figure 1.1. Example of a Procurement Log.
-------
Jan. 1983
Section 2.2.2
2.0 Calibration of Equipment
Before a TSP sampling program is
undertaken, a wide variety of
sampling and analysis equipment
must be calibrated. The calibration
activities are summarized in Table 2.2
at the end of this section. Many of
these activities will also serve as
initial acceptance checks. All data
and calculations required for these
activities should be recorded in a
calibration log book in which a
separate section is designated for
each apparatus and sampler used in
the program.
2.1 Analytical Balance
The calibration should be verified
(1) when the analytical balance is first
purchased, (2) any time it has been
moved or subjected to rough handling,
and (3) during routine operations
when a standard weight cannot be
weighed within ±0.5 mg of its stated
High-Volume Filter-Weighing Quality Control Log
Glass-S weights, g
weight. A set of three to five standard
weights covering the range normally
encountered in weighing filters should
be weighed. If the weighed value of
one or more of the standard weights
does not agree within ±0.5 mg of the
stated value, the balance should be
recalibrated or adjusted by the
manufacturer. The results of all
balance checks should be recorded in
a log book such as the one shown in
Figure 2.1.
Date
7/29/74
7/29/74
7/29/74
7/30/74
7/31/74
7/31/74
7/31/74
7/31/74
7/31/74
8/1/74
18/1/74
K/1/74
'8/1/74
8/1/74
8/1/74
8/1/74
8/2/74
8/2/74
8/2/74
8/2/74
8/2/74
8/2/74
8/2/74
8/3/74
8/3/74
8/5/74
8/5/74
8/5/74
8/5/74
8/5/74
8/5/74
8/5/74
8/6/74
8/6/74
8/6/74
8/6/74
8/6/74
8/6/74
8/7/74
8/7/74
8/7/74
8/7/74
8/7/74
,8/8/74
19/24/74
9/26/74
Time
1 1:07
12:08
240
4:03
9.57
10:56
11.57
2.04
3:05
9:03
1005
11 10
12 12
1:43
242
3.45
8:54
9:56
1059
1216
1:55
3:03
4:00
841
11 15
8.42
9.45
1044
11-46
1 16
221
3.15
9.37
f 1:05
12.10
2.10
3-09
4:05
850
946
1 10
2:20
325
9:46
3:50
3.01
0.5000
0.5000
05002
05000
0.4996
04997
0.4995
0.4996
0.5001
0.5000
0.4998
04999
0.5000
0.4998
0.5000
05001
05001
0.5000
0.5000
05003
05001
04999
0.5000
0.5000
04999
0.5002
0.5001
05000
05000
05000
0.5001
05001
0.5000
0.4999
05000
04999
05000
05000
0.5000
0.5000
0.4996
05001
0.5001
0.5002
0.5000
05001
0.5001
1.0000
1.0002
1.0003
1.0000
09999
1.0000
0.9996
0.9998
1.0OOO
1.0000
09997
0.9997
1.0001
0.9997
1.0001
1.0001
1.0000
1.0001
1.0000
0.9999
1.0002
1.0002
0.9999
0.9998
0.9996
1.0002
1.0000
1.0000
1.0000
1.0001
1.0000
1.0000
1.0000
1.0000
0.9998
09998
0.9998
1.0000
1.0000
1.0002
0.9998
1.0000
1.0000
1.0001
1.0000
1.0001
1.0001
2.0000
2.0000
2.0001
1 9999
2.0002
2.0000
1.9996
1.9998
2.0002
2.0000
7.3937
/.9337
2.000/
1.9998
2.0002
2.0O01
2.0007
2.0007
20007
1.9998
2.0002
2.0007
2.000/
7.9333
7.9390
2.0002
2.0000
2.0000
2.0000
2.0000
2.0000
2.0007
2.0007
2.0000
7.9997
7.9933
2.0000
2.0000
2.0000
2.0003
7.3996
2.0000
2.0000
2.0000
2.0000
2.0007
2.0007
Technician
BSM
DEK
DEK
JLK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
DEK
OEK
DEK
OEK
DEK
Figure 2.1. Example of balance performance record
-------
Section 2.2.2
Jan. 1983
2.2 Relative Humidity
Indicator
The relative humidity indicator used
for monitoring the filter conditioning
environment should be checked
against a wet bulb/dry psychrometer
or the equivalent every 6 months. At
least a two-point calibration should be
made by comparing readings made in
the conditioning environment against
those made outdoors or perhaps just
outside of the conditioning room. If
the difference between the indicator
and the corresponding psychrometer
readings is within ±6%, it is all right
to continue using the relative
humidity indicator; if not, the indicator
must be calibrated or a new one must
be purchased Record the results of
the relative humidity indicator checks
in tVie calibration log book.
2.3 Elapsed-Time Meter
Every 6 months the elapsed-time
meter should be checked against a
timepiece of known accuracy, either
on site or in the laboratory. If the
indicator shows any signs of being
temperature-sensitive, it should be
checked on site during each season of
the year. A gam or loss >2 min/24-h
period warrants adjustment or
replacement of the indicator The
results of these checks should be
recorded in the calibration log book.
2.4 On-Off Timer
The on-off timer should be
calibrated and adjusted quarterly by
using a calibrated elapsed-time meter
as the reference. An example
calibration procedure for one type is
presented below Figure 2.2 depicts
the connection diagram for calibration
of a particular kind of timer The steps
in the procedure are
1. Plug a correctly wired timer into
an electrical outlet
2 Set the timer to the correct time
3 Set the on and off time-trippers
for a 24-h test.
4. Plug the test light into one of the
output plugs, and plug an
elapsed-time meter into the
other.
5. Check the system by manually
turning the switch on and off.
6 Allow the system to operate for
the 24-h test period, and
determine the time elapsed on
the elapsed-time meter. If the
elapsed time is 24 h ±30 mm, the
timer is acceptable for field use;
if not, adjust the tripper switches
and repeat the test. Record the
calibration data in a timer
calibration log such as that
shown in Figure 2.3 Section
Indicator Lamp
On-Off Timer
(±15 mm/24 h>
Elapsed- Time Meter
f±2 mm/24 h)
Figure 2.2. Diagram of a timer calibration system.
2.2.13 provides a blank copy for
the Handbook user.
2.5 Flow Rate Transfer
Standard
Calibration of the high-volume
sampler's flow indicating or control
device is necessary to establish
traceability of the field measurement
to a primary standard via a flow-rate
transfer standard. The calibration
procedure provided here applies to a
conventional orifice-type flow transfer
standard. Other types of transfer
standards may be used if the
manufacturer or user provides an
appropriately modified calibration
procedure that has been approved by
EPA (see 40 CFR, Part 58, Appendix
C, Section 2.8).
Upon receipt and at 1-year
intervals, the calibration of the
transfer standard orifices should be
certified with a positive displacement
standard volume meter (such as a
Rootsmeter) traceable to the National
Bureau of Standards (NBS). Orifice
units should be visually inspected for
signs of damage before each use, and
they should be recalibrated if the
inspection reveals any nicks or dents
in the orifice.
The following equipment is required
for certification of an orifice transfer
standard.
1. Positive-displacement, standard
volume meter (such as Rootsmeter)
traceable to NBS.
2. High-volume air pump (high-
volume sampler blower).
3. Resistance plates or variable
voltage regulator.
4 Stopwatch
5. Thermometer
6. Barometer
7. Manometers [1 mercury (Hg), 1
water, or equivalent]
The following step-by-step
procedure for certification of an orifice
transfer standard is adapted from the
Reference Method.1 An orifice
transfer standard certification
worksheet (Figure 2.4) is provided for
documentation of certification data.
1. Record on the certification
worksheet the standard volume meter
serial number; transfer standard type,
model, and serial number; the person
performing the certification, and the
date
2. Observe the barometric pressure
and record it as Pi (item 8).
3. Read the ambient temperature in
the vicinity of the standard volume
meter and record it as Ti (item 9) (K =
°C + 273).
4. Connect the orifice transfer
standard to the inlet of the standard
volume meter. Connect the mercury
manometer to measure the pressure
at the inlet of the standard volume
meter. Connect the orifice (water)
manometer to the pressure tap on the
orifice transfer standard Connect a
high-volume air pump (such as a
high-volume sampler blower) to the
outlet side of the standard volume
meter. (See Figure 2.5 for an example
of the calibration setup.)
5. Check for leaks by temporarily
clamping both manometer lines (to
avoid fluid loss) and blocking the
orifice with a large-diameter rubber
stopper, wide cellophane tape, or
other suitable means. Start the high-
volume air pump and note any change
in the standard volume meter reading.
The reading should remain constant.
If the reading changes, locate any
leaks by listening for a whistling
sound and/or retightenmg all
connections, making sure that all
gaskets are properly installed.
-------
Jan. 1983
Section 2.2.2
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-------
Section 2.2.2
Jan. 1983
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-------
Jan. 1983
Section 2.2.2
Thermometer
Mercury
Manometer
Barometer
Positive
Displacement
Meter
Orifice Transfer Standard
Variable
Voltage
Transformer
Figure 2.5. Example of orifice transfer standard calibration setup
6. Check the level of the positive
displacement meter table, and adjust
the legs if necessary.
7. After satisfactorily completing
the leak check, shut off motor,
unclamp both manometer lines, and
zero the water and mercury
manometers by sliding their scales
until the zero is even with the
meniscus, as illustrated in Figure 2 6
8. Achieve the appropriate flow rate
through the system, either by means
of the variable flow resistance in the
transfer standard or by varying the
voltage to the air pump. (Use of
resistance plates is discouraged
because the leak check must be
repeated each time a new resistance
late is installed ) At least five evenly
istributed different but constant flow
rates are required, at least three of
which must be in the specified flow
rate interval (1.1 to 1.7 mVmm [39-
60 ftVmm]).
9 Start the blower motor, adjust
the flow, and allow the system to run
for at least 1 mm to attain a constant
motor speed Observe the standard
volume meter dial reading and
simultaneously start the stopwatch
Error in reading the meter dial can be
minimized by starting and stopping
the stopwatch on whole numbers
(e.g , 0046.00)
10 Record the initial meter reading
(V,) in Column 1 Maintain this
constant flow rate until at least 3 m3
of air have passed through the
standard volume meter Record the
standard volume meter inlet pressure
manometer reading as AP (Column 5),
and the orifice manometer reading as
AH (Column 7). Be sure to indicate
the correct units of measurement.
11 After at least 3 m3 of air have
passed through the system, note the
standard volume meter reading and
simultaneously stop the stopwatch
Record the final meter reading (Vi) in
Column 2 and the elapsed time (t) in
Column 3
1 2 Calculate the volume measured
by the primary standard volume meter
(Vm) at meter conditions of
temperature and pressure (using
Equation 1 of the work sheet) and
record in Column 4
Vm = V, - V,
Equation 2-1
1 3 Correct this volume to standard
volume (std m3) by using Equation 2
of the work sheet.
Vsta =
/PI - APV Ts,d\
V p.« AT
-------
Section 2.2.2
Jan. 1983
Mercury
Manometer
Zeroed
Figure 2.6. How to read mercury and water manometers
40
^
: 2 —
r 1~.
'- 0~-
- 1 -
-2-
^ J
••••••I:
Water
Manometer
Zeroed
Pm = 70mm
3.0
2.0
1.0
Mercury
Manometer
Reading
Pm - 70mm
^ A
\
M
P
— 3-
~ 2~
- 1 -
r °i
r '-:
E-2-E
=•3 =
sJ
\ d
I
Water
anometer
Reading
t- 3.0 in
P, = 3 in.
'
0'
0.0
Slope (m) = 2.062
Intercept (b) - -0.056
, 1 I I I , I I I I 1 I I I I I I I I I I <
1 7. If any calibration point does not
fall within ±2% of the line, rerun that
point, recalculate, and replot. The
percent deviation can be calculated by
comparing each Y from Column 7a
against the corresponding Ycai
calculated from the slope and
intercept using Equation 2-4-
Ycai = m Qstd + b
Equation 2-4
The percent deviation for each point is
then calculated using Equation 2-5.
% deviation =Y-Ycaix 100
Ycal
Equation 2-5
18. For subsequent use of the
transfer standard, calculate Qsto as
7.50
0.25 0.50 0.75 7.00 7.25
Qstd. m3/mm
Figure 2.7. Example of orifice transfer standard calibration relationship.
1.75
Equation 2-6
or determine Qstd for each value of:
P;.\/298\
fWV 1* )
from the certification graph.
where:
?2=barometric pressure at time of
2.OO Hi-Vol calibration
T2 = temperature at time of Hi-Vol
calibration
-------
Jan. 1983
Section 2.2.2
2.6 Calibration of High-
Volume Sampler
Each high-volume sampler must
incorporate a flow rate measurement
device capable of indicating the total
sampler flow rate This device may be
an electronic mass flowmeter, an
orifice or orifices located in the
sample air stream together with a
suitable pressure indicator (such as a
manometer or an aneroid pressure
gauge), or any other type of flow
indicator (including a rotameter)
having comparable precision and
accuracy It must be possible to
calibrate the flow rate measurement
device to a flow rate that is readable
(in corresponding units) to the nearest
002stdm3/mm A pressure recorder
with an orifice device that provides a
continuous record of the flow may be
used.
The concentration of TSP in the
ambient air is computed as the mass
of collected particles, divided by the
volume of air sampled, corrected to
standard conditions of 760 mm Hg
and 298 K, and then expressed in
micrograms per standard cubic meter
(A/g/std m3). When samples are
collected at temperatures and
pressures significantly different from
standard conditions, the corrected
concentrations may differ
substantially from actual
concentrations (micrograms per actual
cubic meter), particularly at high
elevations.
Calibration of a high-volume
sampler refers to calibration of the
sampler's flow rate indicator so that it
provides accurate measurements of
the sample flow rate from which the
volume of the sampled air can be
calculated. Details of the calibration
procedure vary somewhat depending
on (1) the type of flow indicator used,
(2) whether the sampler is equipped
with an automatic flow controller, and
(3) whether the calibration is to
incorporate the geographical average
barometric pressure and seasonal
average temperature at the sampling
site. The basic procedure for nonflow-
controlled samplers is given in
Subsection 2.6 2, whereas the
variations in the procedure necessary
for flow-controlled samplers are
presented in Subsection 2 6.3.
Orifice-type flow indicators are
sensitive to changes in both
temperature and barometric pressure.
Because ambient temperature and
barometric pressure vary from day to
day, the calibration procedure
contains a formula to correct for this
variability. Errors resulting from
normal daily fluctuation are relatively
small, however, compared with
barometric differences due to
elevation and seasonal temperature
changes. Thus, if the modest errors
due to daily changes are acceptable,
the average barometric pressure for a
given elevation and the seasonal
average temperature for that location
can be incorporated directly into the
sampler calibration with little error
being introduced in the calculated
flow rate.
When this is done, the sampler is
calibrated for the average temperature
and pressure conditions at the site,
and no further temperature or
pressure corrections are needed for
the flow indicator reading to be used
to determine the sampler flow rate.
The relationship between the flow
indicator reading and the standard
volume flow rate then becomes a very
simple one. This relationship also can
be easily reduced to a simple three-
column table (indicator reading,
winter flow rate, and summer flow
rate) suitable for use even by
nontechnically oriented operators
The average barometric pressure for
a site can be estimated from the
altitude of the site, either by using an
altitude-pressure table or by reducing
the sea level pressure of 760 mm Hg
by 26 mm Hg for each 305 m (1000
ft) of altitude. The average pressure
could also be determined by averaging
onsite barometer readings or nearby
weather station or airport
measurements (station pressure,
uncorrected) over several months. The
seasonal average temperature for a
site can be estimated from onsite
temperature readings or nearby
weather station records over the
season. Ideally, the average
temperature should reflect the
temperature at the time of day at
which the flow indicator would
normally be read; however, an
average determined from 24-hour
mean temperature records would be
acceptable For most sites, two
seasonal average temperatures
(summer and winter) are sufficient;
for sites where climatic changes are
severe, however, four seasonal
average temperatures may be needed
to accommodate the changes. Where
computers are used to process TSP
data, monthly average temperatures
could be used. Ideally, the
seasonal average temperature
should generally be within ±15°C of
the local ambient temperature at the
time the flow indicator is read. If daily
temperature changes at the site are
too drastic to be represented by a
seasonal average (±15°C) actual
temperature corrections should be
used each time a flow reading is
obtained.
Once a decision has been made on
whether to incorporate an average
barometric pressure and a seasonal
average temperature into the
calibration, the appropriate expression
for plotting or calculating the sampler
calibration can be selected from Table
2.1. The use of this expression is
explained m Subsection 2.6.2.
2.6.1 Calibration Schedule - High-
volume-sampler flow-rate devices
should be calibrated with a certified
flow-rate transfer standard such as an
orifice calibration unit (1) upon
receipt, (2) after motor maintenance,
(3) any time the flow rate device is
repaired or replaced, and (4) any time
the difference between the sample
flow rate and a one-point audit
deviates more than +7 percent.
2.6.2 Sampler Calibration Procedure
- The procedures for multipoint
calibration of a high-volume sampler
are specified in 40 CFR 50, Appendix
B (reproduced in Section 2.2.11). To
facilitate these procedures, calculation
data forms have been developed to aid
m making the calibrations. These
forms also may be used for the
calibration of other types of high-
volume flow measuring devices,
Table 2.1. Expressions for Plotting Sampler Calibration Curves
Type of sampler For actual pressure For incorporation of
flow rate measuring
device
and temperature
corrections
geographic average pressure and
seasonal average temperature
Mass flowmeter
Orifice and pressure
indicator
Rotameter. or orifice
and pressure
recorder having
square root scale'
I
f(£X¥) {'
298
"This scale is recognizable by its nonuniform divisions; it is the most commonly
available for high-volume samplers.
-------
Section 2.2.2
Jan. 1983
provided the appropriate equations
and procedures are followed
Documentation of all data on the
flow-rate transfer standard for the
high-volume site sampler, and the
calibration procedures are of primary
importance The validity of the data
collected by the instrument is
dependent on the quality of the
calibration; thus the calibration must
be performed with a transfer standard
that meets all conditions specified in
Subsection 2 5
The following procedure, which
involves the use of the forms shown
in Figures 2 8 and 2.9, is given to aid
in the collection and documentation of
calibration data This procedure
applies primarily to a conventional
orifice-type flow transfer standard and
an orifice-type flow indicator with a
flow recorder in the sampler (the most
common type), as shown m Figure
2 10
1 Record the official name and
address of the station on the form;
where appropriate, the name and
address should be the same as that
appearing on the SAROAD site
identification form to eliminate any
confusion to persons not familiar with
the station.
2 Connect the transfer standard
orifice to the inlet of the sampler.
Connect the orifice manometer to the
orifice pressure tap, as illustrated in
Figure 2.10 Make sure there are no
leaks between the orifice unit and the
sampler.
3. Verify that the flow indicator or
recorder is properly connected to the
pressure tap on the lower side of the
high volume sampler moto'r housing.
Install a clean flow chart in the
recorder and adjust the recorder pen
to read zero.
4. Operate the sampler for at least
5 minutes to establish thermal
equilibrium prior to the calibration
5. Measure and record the
barometric pressure (Pz) and ambient
temperature (T2) on the calibration
worksheet (Items 1 and 2 on the
upper part of the sheet).
6. Adjust the variable resistance of
the transfer standard, or if applicable,
insert the appropriate resistance plate
to achieve the desired flow rate. If
samplers have an orifice-type flow
indicator downstream of the motor, do
not vary the flow rate by adjusting the
voltage or power supplied to the
sampler
7. Let the sampler iun for at least 2
minutes to reestablish the run-
temperature conditions Read and
record the pressure drop across the
transfer standard orifice (AH) under
Column 1 of the worksheet Read the
sampler flow rate indication (I) from
the flow recorder and record under
column 4 Tap the flow recorder
lightly before taking each reading to
assure that the pen is not sticking.
8 Calculate y'AH (P2/Pstd} (298/T2)
and record under column 2.
9 Determine the standard
volumetric flow rate (Q5td) either
graphically from the transfer standard
certification curve or by calculating
Qstd from the least squares slope and
intercept of the transfer standard's
transposed certification curve
Qs,d = 1 /m [yAH (Pa/Pstd) (298/T2) - bj
Equation 2-6
(repeated)
Record the value of CUto under
Column 3
10. Repeat steps 6 through 9 for at
least four additional flow rates
distributed over a range that includes
1 1 to 1 7 std mVmm
11 For each calibration point,
calculate a Y value from the
appropriate expression selected from
Table 2-1 for the flow device being
calibrated This should be done
whether or not average barometric
pressure and seasonal average
temperature are to be incorporated
into the calibration. Record this value
under the appropriate side of Column
5 Calibration Worksheet (Figure 2.8),
and mark the box showing which
expression was used. For a pressure
recorder, use the lower expression for
square root function chart paper or
middle expression for linear (uniform)
chart paper.
12 Determine the calibration
relationship by plotting the
corresponding values of the Y
expression involving I against Qstci on
a graph similar to that shown in
Figure 2.9. The Y expression plotted
on the Y axis is from Column 5 of the
calibration worksheet; the Qstd plotted
on the X axis is from Column 3.
13 Draw the sampler calibration
curve and/or calculate the linear least
squares slope (m), intercept (b), and
correlation coefficient of the
calibration curve Calibration curves
should be readable to 0.02 std
mVmin.
14. After the calibration
relationship is determined, recheck
each calibration point to determine if
it is within the limits of linearity
(±5%). This can be done by
determining a Ycai for each Qstd value
recorded under Column 3 of the
calibration worksheet. Ycai can be
determined from the calibration curve
drawn in Figure 2 9 or by using the
slope (m) and intercept (b) from the
calibration worksheet (Figure 2.8) m
the following equation
Ycai = rn Qsid + b
Equation 2-7
The percent difference for each
value (Qstd) is determined by
comparing each Ycai with the
corresponding Y recorded under
Column 5 of the worksheet by using
the following equation.
% difference = Y - ycai x 100
Yea,
Equation 2-8
where
Y = Value of appropriate
expression as recorded under
Column 5 of the calibration
worksheet
Ycai = Corresponding Y value for the
same Qstd as determined from
the calibration relationship
(Equation 2-7)
Any calibration points that are found
to have a greater difference than ±5
percent should be repeated, and a
corrected calibration relationship
should be recalculated
The use of the calibration
relationship determining sampler
flow rates and the appropriate
expressions to be used are discussed
later in Subsection 4.4
2.6.3 Flow-Controlled Sampler
Calibration Procedures - Samplers
equipped with a flow controlling
device may be calibrated either by
means of a full multipoint calibration
of the flow indicator (as described in
Subsection 2.6.2 or by a single point
calibration of the flow controller,
without calibrating the flow indicator.
Multipoint Calibration. The flow
controller must be rendered
inoperative to allow flow changes to
be made during calibration of the flow
indicator. Calibration procedures and
data forms given in Subsection 2.6.2
can then be used to determine the
calibration relationship for the
sampler's flow indicator. After
calibration, the flow-controlling
mechanism should be made operative
again and set to a flow near the lower
flow limit (1.1 std mVmm) to allow
maximum control range. At this time
the sample flow rate should be
verified with a clean filter installed.
Two or more filters should then be
added to the sampler to see if the
flow controller maintains a constant
flow; this is particularly important at
high altitudes where the range of the
flow controller may be reduced.
Single-Point Calibration. A flow-
controlled sampler may be calibrated
solely at its controlled flow rate,
-------
Jan. 1983
Section 2.2.2
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Section 2.2.2
10
Jan. 1983
60.01 i i i i | i i i
Slope (ml = 32.779
Intercept = 3 957
Corr. Coif = 9937
0.0 0.25 0.50 0.75 1.00 125 1.50 175 200
Qstd, m mm
Figure 2.9. Example of a high-volume sampler calibration relationship.
provided the previous operating
history of the sampler demonstrates
that the flow rate is stable and
reliable. In this case, the flow
indicator may remain uncahbrated,
but it should be used to indicate any
relative change between initial and
final flows, and the sampler should be
recalibrated more often to minimize
potential loss of samples because of
controller malfunction. The following
procedures should be used.
1. Set the flow controller for a flow
near the lower limit of the flow range
(1.1 std mVmin) to allow maximum
control range.
2. Install a clean filter in the
sampler and carry out steps 2 through
5 and 7 through 9 of Subsection 2.6.2.
No resistance plate should be used
with the flow rate transfer standard.
3. Following calibration, add one or
two additional clean filters to the
sampler, reconnect the transfer
standard, and operate the sampler to
verify that the controller maintains the
same calibrated flow rate; this is
particularly important at high
altitudes, where the flow control
range may be reduced.
following procedures may be used.
(Refer to Figure 2.11, a photographic
copy of the rotameter, to identify the
working components in this
procedural step for adjusting the
rotameter.)
1 Attach the rotameter to the high-
volume sampler motor.
2. Turn on motor and adjust to
selected flow rate.
3 If adjustment is necessary, hold
the rotameter vertically and loosen
the locking nut by turning it
counterclockwise.
4. Turn the adjusting screw to the
desired setting (clockwise to lower the
ball, or counterclockwise to raise the
ball).
5. Be sure the ball continues to
read the desired setting after the
adjustment is made and as the locking
nut is tightened.
6. Seal both the locking nut and the
adjustment screw with glue to assure
that the setting does not change. Do
not cover the exhaust orifice
7. Proceed with calibration of
rotameter as specified in Subsection
2.6.2.
2.6.4 Rotameter Calibration
Procedure - High-volume samplers
equipped with rotameters are
calibrated by using the same
procedures and forms as specified in
Subsection 2.6.2. Should adjustment
of the rotameter be necessary, the
-------
Jan 1983
11
Section 2.2.2
Figure 2.10 High volume sampler and orifice unit assembled for calibration with flow
recorder
-------
Section 2.2.2
12
Jan. 1983
Spring-Clip
Backing Plate
Spring-Clip Support
Adjusting Screw
Locking Nut
Exhaust Orifice
Tapered Plastic Tube
Inlet Port
Base Screw
Backing Plate
Figure 2.11. Example of high volume sampler rotameter
Scale
-------
Jan. 1983
13
Section 2.2.2
Table2.2. Activity Matrix for Calibration of Equipment
Equipment
Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
Analytical balance
Relative humidity indicator
On-off timer
Elapsed-time meter
Flow-rate transfer standard
Sampler
Indicated weight - true
weight ±0.0005 g
Indicator reading -
psychrometer reading ±6%
±30 min/24 h
±2 min/24 h
Indicated flow rate (from
previous calibration) -
actual flow rate ±2%
Indicated flow rate - actual
individual calibration
points ±5% of linearity
Gravimetvic test-weighing
at purchase and during
periodic calibration checks;
use three to five standard
weights covering normal
range of filter weights.
Compare with reading of
wet bulb/dry bulb psychro-
meter on receipt and at
6-mo intervals.
Check at purchase and
quarterly with elapsed-
time meter.
Compare with a standard
timepiece of known
accuracy at receipt and at
6-mo intervals.
Check at receipt and at 1 -yr
intervals against positive-
displacement standard
volume meter; recalibrate
or replace orifice unit if
damage is evident.
Calibrate with certified
transfer standard on
receipt, after maintenance
on sampler, and any time
audit deviates more than
±7%.
Have balance repaired
and/or recalibrated
Adjust or replace to attain
acceptance limits
Adjust or repair
Adjust or replace time
indicator to attain accept-
ance limits.
Adopt new calibration
curve.
Recalibrate.
-------
Jan. 1983
Section 2.2.3
3.0 Filter Selection and Preparation
Suppliers of glass fiber filters for
measurement of TSP have two grades
of materials—the standard or
traditional grade that has been in use
for more than 20 years and a spectro-
quality grade. Because the spectro-
quality grade contains less organic
and inorganic contaminants, it is
recommended for use where
additional chemical analyses are
anticipated A filter with low surface
alkalinity is preferred to avoid positive
interferences from absorption of acid
gases while sampling. Ideally, surface
alkalinity should be between pH 6 5
and 7 5; however, most commercially
available glass fiber filters have a pH
of >7.5. Filters having a pH of
between 6 to 10 are acceptable. An
activity matrix for filter selection and
preparation is presented as Table 3.1
at the end of this section.
3.1 Selection
Only filters having a collection
efficiency of >99 percent for particles
of 0.3-fjm diameter (as measured by
the OOP test ASTM-D2986-71) are to
be used. The manufacturer should be
required to furnish proof of the
collection efficiency of a batch of new
filters. The collection efficiency should
be recorded in the procurement log.
Figure 1.1 of Section 2 2.1.
Each filter should be visually
inspected using a light table. Loose
fibers should be removed with a soft
brush. Discard or return to the
supplier the filters with pmholes and
other defects such as tears, creases,
or lumps
3.2 Identification for Filters
Not Numbered by the
Supplier
A serial number should be assigned
to each filter. The number should be
stamped on two diagonally opposite
corners—one stamp on each side of
the filter Gentle pressure should be
used in application to avoid damaging
the filter.
3.3 Equilibration
Each-filter should be equilibrated in
the conditioning environment for 24 h
before weighing to minimize errors in
the weight; longer periods of
equilibration will not affect accuracy.
The conditioning environment
temperature should be between 15°
and 30°C (59° to 86°F) and should
not vary more than ±3°C (5°F); the
relative humidity (RH) should be
<50% and not vary more than ±5%. A
convenient working RH is 40%
3.4 Weighing
Clean filters are usually processed
in lots—that is, several at one time.
Clean filters must not be folded or
creased prior to their weighing or use.
Before the first filter is weighed, the
balance should be checked by
weighing a standard Class-S weight
of between 3 and 5 g Actual and
measured weights, the date, and the
operator's initials should be recorded,
as shown in Figure 2.1.
, If the actual and measured values
differ by more than ±0.5 mg (0.0005
g), the values should be reported to
the supervisor before proceeding. If
the actual and measured values agree
within ±0.5 mg, each filter should be
weighed to the nearest milligram
Each filter should be weighed within
30 seconds after removing it from the
equilibration chamber, and the tare
weight and the serial number of each
filter should be recorded in the
laboratory log (Figure 3.1). Section
2.2.13 contains a blank copy of Figure
3.1 for the Handbook user. Note:
Sihcone-treated high volume filters
have been found to have a static
charge problem. This problem can be
eliminated by placing an antistatic
device containing a low-level alpha
radiation source within the balance
chamber. These devices are
commercially available
3.5 Handling
A quantity of filters sufficient for a
>3-mo period for each sampler should
be numbered and weighed at one
time. Pack the filters in their original
container (or a box of similar size) so
that each filter is separated by a sheet
of 81/2-by-11-in. tracing paper. Be sure
the filters are stacked in the box in
numerical order so that the operator
will use the proper filter first.
In addition to the filters, the field
operator should be supplied with
preaddressed return envelopes to
protect the filters during mailing;
these can be printed front and back to
serve as a sample record data form,
as shown in Figure 3.2. Section
2.2.13 contains a blank copy of Figure
3.2 for the Handbook user.
-------
Section 2.2.3
Jan. 1983
Laboratory Log for Total Suspended Paniculate Data
A/OTOkm . OHIO Tntal Si/cnPnriPri Partirulal*
City Name
_. . , . Name Parameter
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i paniculate data
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-------
Jan. 1983
Section 2.2.3
Comments
Figure 3.2. Hi- Vol field data form.
Hi- Vol Data Record
Pro/ect
Station
Site and/or Sampler No
SAROAD Site Code
Sample Date
Filter No
Flow Reading initial
final -
Average Flow Rate .
Running Time Meter initial
final _
Total Sampler Time
Total Air Volume
Net TSP Weight
TSP Concentration
Optional
, std m3
. fjg/std m3
Temperature
Barometric Pressure
initial _
final -
average
Operator
-------
Section 2.2.3
Jan. 1983
Table3.1. Activity Matrix for Filter Selection and Preparation
Activity
Selection and collection
efficiency
Integrity
Identification
Equilbration
Weighing procedure
Handling
Acceptance limits
Frequency or method
of measurement
Action if
requirements
are not met
Efficiency of >99% in 0.3-
/jm diameter particle
collection
No pinholes, tears, creases,
etc.
Identification number in
accordance with specifica-
tions
Equilibration in controlled
environment for >24 h;
constant humidity chamber
with RH of <50%
constant within ±5%,
temperature between 15°
and 30°C with less than
±3°C variation
Indicated filter weight
determined to nearest mg
within 30 s after removing
from the equilibration
chamber.
Filter in protective folder;
envelopes undamaged
Manufacturer's proof of
OOP test ASTM-D2986-7J
Visual check of each filter
with light table
Visual check of each filter
The room or chamber
conditions and the equili-
bration period are observed
for each sample.
Observation of weighing
procedure
Visual check of each filter
Reject shipment or return
to supplier
Discard filter
Identify properly or discard
filter
Repeat equilibration
Fteweigh after re-equilibra-
t/on
Replace undamaged filters.
discard damaged filters
-------
Jan. 1983
Section 2.2.4
4.0 Sampling Procedure
The activity matrix presented as
Table 4 2 at the end of this section
summarizes the sample collection
activities and the operational checks
4.1 Filter Installation
Care must be taken to assure that
the clean weighed filters are not
damaged or soiled prior to installation
in the high-volume sampler They
should be kept in a protective folder or
box and must not be bent or folded
The use of filter cassettes (Figure 4 1)
that can be loaded and unloaded in
the laboratory may be used to
minimize damage to the filter
Damaged or soiled filters must be
discarded
The following procedures are used
to install a filter
1 Open the shelter and remove the
faceplate of the sampler by loosening
the four Wmgnuts and swinging the
bolts outward
2 Wipe all dirt from the support
screen and faceplate.
3 Center the filter with the rough
side up on the wire screen so that the
gasket will form an airtight seal on
the outer edge (1 cm) of the filter
when the faceplate is in position.
When aligned correctly, the edges of
the filter will be parallel both to the
edges of the screen behind it and to
the faceplate gasket above it. Poorly
aligned filters show uneven white
borders (Figure 4.2) around the filter.
4 Tighten the four wmgnuts just
enough to prevent leakage when the
filter is aligned and the faceplate is in
Figure 4.1 High volume sampler filter cartridge assembly
olace. Excessive tightening may cause
the filter to stick or permanently
damage the gasket.
5 Close the shelter and run the
sampler for at least 5 mm to establish
run-temperature conditions.
6. Record the flow indicator reading
and, if needed, the barometric
pressure (Ps ,mtiai) and the ambient
temperature (T3 ,mtiai), then stop the
sampler. Note. No onsite pressure or
temperature measurements are
necessary if the sampler flow
indicator does not require pressure or
temperature corrections (e g., a mass
flowmeter) or if average barometric
pressure and seasonal average
temperature for the site have been
incorporated into the sampler
calibration. For individual pressure
and temperature corrections, the
ambient pressure and temperature at
the time of the flow indicator reading
can be obtained by onsite
measurements or from a nearby
weather station. Barometric pressure
readings obtained from airports must
be station pressure, not corrected to
sea level, and may need to be
corrected for differences in elevation
between the sampler site and the
airport. For samplers having flow
recorders but not constant flow
controllers, the average temperature
and pressure at the site during the
sampling period should be estimated
from U S Weather Bureau or other
available data.
7. Determine the flow rate from the
sampler's calibration relationship
(Subsection 4.4) to verify that it is
operating within the acceptable range
of 1.1 to 1.7 mVmm (39-60 ftVmm).
If not within this range, use a
different filter or adjust the sampler
flow rate Warning: Substantial flow
adjustments may affect the calibration
of orifice-type flow indicators and may
necessitate their recalibration
8. Record the sample identification
information (filter number, site
location or identification number,
sample date) and the initial flow rate
(or flow indicator reading and
temperature and barometric pressure
if needed) on the Hi-Vol field data
form (Figure 4.3). See Subsection 4.7
for proper documentation.
9. Set the timer to start and stop
the sampler such that the sampler
runs 24 hours, from midnight to
midnight local time.
-------
Section 2.2.4
Jan. 1983
Figure 4.2. Nonuniform borders resulting from poorly aligned filters
4.2 Retrieval of Exposed
Filter and Post-Sampling
Checks
1. As soon as practical following
the sampling period, run the sampler
for at least 5 min to reestablish run-
temperature conditions.
2. Record the flow indicator reading
and, if needed, the barometric
pressure (Pa f,nai) and the ambient
temperature (T3 finai)
3. Stop the sampler, remove the
faceplate, and lift the exposed filter
from the supporting screen by
grasping it gently at the ends, not at
the corners.
4. Check the filter for signs of air
leakage. Leakage may result from a
worn faceplate gasket (Figure 4 4) or
from an improperly installed gasket. If
signs of leakage are observed, void
the sampler, determine the cause, and
take corrective actions before starting
another sampling period A gasket
generally deteriorates slowly; thus the
operator can decide well in advance
(by the increased fuzzmess of the
sample outline) when to change the
gasket before a total failure results
5. Visually inspect the gasket face
to see if glass fibers from the filter are
being left behind due to
overtightenmg of the faceplate
wingnuts and the consequent cutting
of the filter along the gasket interface.
6. Check the exposed filter for
physical damage that may have
occurred during or after sampling.
Physical damage after sampling would
not invalidate the sample if all pieces
of the filter were put in the folder;
however, sample losses due to
leakages during the sampling period
or losses of loose particulates after
sampling (e.g , loss when folding the
filter) would invalidate the sample, so
mark such samples "void" before
forwarding them to the laboratory.
7. Check the appearance of the
particulates Any changes from
normal color, for example, may
indicate new emission sources or
construction activity in the area. Note
any change on the filter folder along
with any obvious reasons for the
change.
8. Fold the filter lengthwise at the
middle with the exposed side in; if the
collected sample is not centered on
the filter (i.e , the unexposed border is
not uniform around the filter), fold so
that only the deposit touches the
deposit Results of an improperly
folded filter are illustrated in Figure
4 5, where smudge marks from the
deposit extend across the borders; this
can reduce the value of the sample if
the analyses for which the sample
was collected need to be divided into
equal portions.
9. Place the filter in its numbered
folder.
10. Determine the final flow rate
from the sampler's calibration
relationship (see Subsections 4.3 and
4.4) and record it on the data record
along with other pertinent information
(see Figure 4.3).
11. Remove the sampler's flow
recorder chart and place the chart
inside the filter folder with the inked
side against the folder and the
backside against the filter.
4.3 Flow Readings
4.3.1 Rotameters - To obtain a valid
measurement, make flow rate
-------
Jan. 1983
Section 2.2.4
Hi- Vol Data Record
Project
Station
Comments
, CAL.
CITY
ON. DA
^
Site and/or(§ampler
. lx/A<, CLO^U-ECTED.
Sample Date
Filter No
SAROADSiti Code
" 73
/•
Flow Reading initial
final LJ.
Average Flow Rate
'• *^
Running Time Meter initial
final _
QOOO
Total Sampler Time
/ Jo
Total Air Volume
/Ote 7»
TSP Concentration
Optional
. fjg/std m3
Temperature
Barometric Pressure
initial
final
, average
Figure 4.3. Example of completed Hi- Vol field data form.
measurements while the sampler is at
normal operating temperature, after a
warmup time of >5 min.
1. Connect the rotameter to the
sampler with the same tubing used
during calibration, and place or hold
it in a vertical position at eye level.
2. Read the widest part of the float
(ball), and use the calibration
relationship (see Subsection 4.4) to
convert the reading to Q8w (mVmin)
and record to the nearest 0.02,td
mVmin.
3. Measure the flow rates at the
beginning and end of each sampling
period. Observe the flow rate for >1
min after connecting the rotameter to
the sampler, before taking a reading. If
a gradual change in flow rate is
observed, do not take a reading until
equilibrium is reached; a gradual
change is usually observed when the
rotameter is at a substantially
different temperature from that of the
sampler exhaust air, and thus
equilibration may require 2 or 3 min.
4.3.2 Flow Recorders - The
following procedure is for a high-
volume sampler equipped with a flow
recorder.
2. Remove any moisture by wiping
the inside of the recorder case with a
clean cloth. Carefully insert the new
chart into the recorder without
bending the pen arm beyond its limits
of travel. An easy way to do this is to
raise the pen head by pushing in on
the very top of the pen arm with the
right hand while inserting the chart
-------
Section 2.2.4
Jan. 1983
Figure 4.4. Example of air leakage around the filter due to worn faceplate gasket or to
improper installation
with the left hand. Be careful not to
damage or weaken the center tab on
the chart, but be sure the tab is
centered on the slotted drive so that
the chart will rotate the full 360
degrees in 24 h without binding or
slipping. A properly installed chart is
shown in Figure 4.6.
3. Check to see that the pen head
rests on zero (i.e., the smallest circle
diameter on the chart). If not, tap the
recorder lightly to make certain that
the pen arm is free.
4. Check the time indicated by the
pen. If it is in error, rotate the chart
clockwise by inserting a screwdriver
or coin into the slotted drive in the
center of the chart face until the time
is correct. If the sampler is started
with a timer switch, the correct time
is the starting time on the timer
(usually midnight).
5. Using an eyedropper, put a small
amount of ink into the hole in back of
the pen tip. Use of cartridge-type pens
will minimize problems with inking.
6. Turn the sampler on (never turn
it on until a filter is in place because
the transducer and recorder may be
damaged), and observe it long enough
to know whether the transducer and
recorder are operating properly
4.4 Determination of Flow
Rates
High-volume sampler flow rate
readings must be converted to units of
std mVmin (25°C, 760 mm Hg) for
use in calculating TSP concentrations.
Expressions for converting sampler
flow rate readings (I) to standard
conditions are given m Table 4 1
Instructions for the use of this table
and the flow measuring device
calibration relationships (Figures 2 8
or 2 9) to obtain the sampling flow
rate Cum (mVmin) are given in
Subsections 4.4 1 and 442
No onsite pressure or temperature
measurements are necessary if the
sampler flow indicator does not
require pressure or temperature
corrections (e g., a mass flowmeter) of
if average barometric pressure and
seasonal average temperature for the
site have been incorporated into the
sampler calibration For individual
pressure and temperature corrections,
the ambient pressure and temperature
at the time of flow indicator reading
can be obtained by onsite
measurements or from a nearby
weather station. Barometric pressure
readings obtained from airports must
be station pressure, not corrected to
sea level, and may need to be
corrected for differences in elevation
between the sampler site and the
airport For samplers having flow
recorders but not constant flow
controllers, the average temperature
and pressure at the site during the
sampling period should be established
from Weather Bureau or other
available data
4.4.1 Samplers Without Continuous
Flow Recorders - For a sampler
without a continuous flow recorder,
determine the appropriate expression
to be used (from Table 4 1)
corresponding to the one used in
calibration (from Table 2 1) Using this
appropriate expression, determine Qstd
for the initial flow rate from the
sampler calibration curve, either
graphically or from the transposed
regression equation (see Figure 2 8)'
Qstd =-L ([Appropriate expression from
m Table 4 1] - b)
Equation 4-1
Similarly, determine Qstd from the
final flow reading, and calculate the
average flow Qstd as one-half the sum
of the initial and final flow rates.
4.4.2 Samplers With Continuous
Flow Recorders - For a sampler with a
continuous flow recorder, determine
the average flow rate reading (I) for
the period Determine the appropriate
expression from Table 4.1
corresponding to the one used m
calibration (from Table 2.1) Then
using this expression and the average
flow rate reading, determine Qstd from
the sampler calibration relationship,
either graphically or from the
-------
Jan. 1983
Section 2.2.4
Figure 4.5. Example of smudged filter border resulting from an improperly folded filter.
Table 4.1. Expressions for Determining Flow Rate During Sampler Operation
Expression
For use when geographic
average pressure
and seasonal average
Type of sampler For actual pressure temperature have been
flow rate measuring and temperature incorporated into the
device corrections sampler calibration
Mass flowmeter 1
Orifice and pressure 1 1 / / PS_ \ I
indicator J| \/w'
Rotameter, or orifice
recorder having / \ii PS
square root scale* y \ pstd /
'298\
v 7-3 )
\(298\
KTT)
*This scale is recognizable by its nonuniform divisions and is
available for high-volume samplers
/
P-
/
the most commonly
transposed regression equation (see
Figure 2.8 and Equation 4-1 above):
If the trace shows substantial flow
change during the sampling period,
greater accuracy may be achieved by
dividing the sampling period into
intervals, calculating an average
reading for each interval, determining
Qstd for each interval, and finally
•computing the average Qsta for the
whole sampling period.
Calculate the total air volume
sampled by the following equation:
V = CW t Equation 4-2
where:
V=total air volume sampled, in
standard volume units (std m3);
Qsta-average standard flow rate, std
mVmin;
t = sampling time, mm.
4.5 Sampling Flow Rate
Checks
The two types of sampling flow rate
checks recommended are discussed in
the following Subsections (4.5.1 and
4.5.2).
4.5.1 Initial Flow Rate Check - Initial
flow rate measurements should be
monitored for each sampler to
determine whether corrective action is
needed.
1. Record the initial and final flow
rates for each sample in the log book
maintained with the sampler. A
sampler equipped with a continuous
recorder should be observed for at
least 5 mm. before the initial flow rate
is recorded.
2. Average the initial flow rate
measurements for the first four
samples after each calibration. Check
future initial flow rates that deviate
more than ±10% from this average
for samplers on which a manometer
or a flow recorder is used and ±15
percent for samplers on which a
rotameter is used. If the change has
been gradual over time, recalibrate. If
large deviations occur between
successive samples, repeat the flow
reading after 5 minutes. If the second
reading is within the above limits,
continue normal operations; if not,
check the line voltage and/or replace
the filter
3. Perform a calibration check if
neither of the above checks identifies
the trouble. If the calibration check is
satisfactory, continue normal
operations; if not, perform a complete
calibration
4.5.2 Operational Flow Rate Check -
It is recommended that a one-point
operational flow check be made on
each sampler at least once every 2
weeks. The purpose of this check is to
-------
Section 2.2.4
Jan 1983
Figure 4 6 Flow rate recorder with chart installed
track the m-control conditions of the
sampler calibration The same flow
rate transfer standard used to
calibrate the high-volume sampler
may be used for the operational flow
check
1 Operate the sampler at its
normal flow rate with flow check
device in place Determine Qstd for the
check point from the calibration of the
flow check device, and determine the
measured flow rate from the
sampler's calibration (see Subsections
43 and 4 4) Use the following
procedure for plotting the check data
2 Calculate the percentage
difference (% D) between the known
check flow measurement and the flow
measured by the sampler's normal
flow indicator (Equation 4-1) Let Qa
represent the known flow rate and Qm
the measured flow rate for the flow
check
Equation 4-3
Thus if Qm = 1 .48 mVmm and Qa =
1 42 mVmm
then
% D =/1.48- 1 42 1 00 = +4%
.n=(l.48-1 42\1
\ 1.42 /
If the % D is not within ±7 percent for
any one check, recalibrate before
resuming the sampling
3 Record the Qm, the Qa, and the %
D on an X-and-R chart (Figure 4 7)
under "Measurement Result, Items 1
and 2 " Record the % D m the cells
preceded by the "Range R " The % D
can be positive or negative, so retain
the sign of the difference, since it may
indicate trends and/or consistent
biases More information on the
construction of a quality control chart
and the interpretation of the results
are in Appendix H, Volume I of this
Handbook 2
4. Repeat the above for each
operational flow rate check, plot all
points on the chart, and connect the
points by drawing connecting lines
Tentative limits are ±4 7 percent
(warning lines) and ±7 percent (out-
of-control lines) Out-of-control points
indicate possible problems in
calibration or instrument errors When
out-of-control results are obtained,
recalibrate the sampler prior to further
sampling After 1 5 to 20 points are
plotted, new control and warning
limits may be derived, as described in
Appendix H of Volume I of this
Handbook.2 Do not increase the
control and warning limits, however,
more stringent limits may be
established _
5 Forward the X-and-R chart to the
QA supervisor for review
4.6 Time Measurements
Start and stop times for samplers
not equipped with a timer switch or
an elapsed-time meter are recorded
by the operator who starts and stops
the sampler If more than one
operator is involved, each should set
his/her watch to a common reference
to achieve accurate times, such a
reference could be an office clock that
is checked daily or the local telephone
company, which gives the time of day
The time measurement procedure is
as follows
1 Take the start and stop times for
samplers equipped with timer
switches from the timers' start and
stop settings
2 Check the timer clock, and set it,
if necessary, for the correct times at
each filter change
3 Use an elapsed-time meter to
determine the number of minutes
sampled because timers cannot be set
or read to within less than ±30 mm
4.7 Documentation
The following information should be
recorded on the filter folder or on a
field data record form (Figure 4 3) by
the persons indicated, and it should
be verified with a signature
4.7.1 The Operator Who Starts the
Sample
1 Station location
2 Project number
3 Site number
4 Sampler ID number
5 Filter number
-------
Jan. 1983
Section 2.2.4
SO]
ll
I
1
(S
-------
Section 2.2.4
Jan. 1983
6 Sample date
7 Initial flow reading (if using
rotameter) and/or initial temperature
and barometric pressure if required
8. Unusual conditions that may
affect the results (e.g., subjective
evaluation of pollution that day,
construction activity, meteorology)
9 Signature.
4.7.2 The Operator Who Removes
the Sample
1 Elapsed time
2. Final flow reading (or be sure
that the flow rate chart accompanies
the sample) and final temperature and
barometric pressure if required
3. Existing conditions that may
affect the results
4. Signature
4.7.3 The Operator Who Transfers
the Sample to the Laboratory Record
1. Receiving date initialed
2. Shipping date initialed
Table 4.2. Activity Matrix for Sampling Procedure
Activity
Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
Filter installation
Flow checks
Elapsed time
Sample handling
Documentation
Filter rough side up,
centered on screen, edges
parallel to edges of screen
and to faceplate gasket,
gasket tightened to prevent
leakage
1) Sampler flow rate within
acceptable range of 1 1 to
1.7 m3/min (39-60 ft3/mm)
2) Stabilized initial flow
rate = established initial
flow rate ±10% for
pressure transducer or
+ 15% for rotameter
3) Sampling time 24 ±1 h
No evidence of malfunction
in post-sampling check
Names, sampling dates,
times; sample, filter, and
station numbers; unusual
conditions, flow rates, and
hand/ing dates recorded on
sample envelope
Visually check each
exposed filter.
Check flow rate at each
filter change
Check on and off settings
of timers
Visually check each sample
for tears, missing pieces,
or leakage
Visually check each sample
data record
Void the filter; install
substitute filter
1 j Determine cause of flow
problem and correct;
measure line voltage,
change the filter, check
calibration and calibrate
sampler.
Reset timer
Void the sample; correct
the cause of ma/function.
Complete or correct the
documentation; if unavail-
able, void the sample.
-------
Jan. 1983
Section 2.2.5
5.0 Analysis of Samples
A matrix summarizing the major
quality assurance activities for sample
analyses is presented as Table 5.1 at
the end of this section.
5.1 Sample Documentation
and Inspection
Upon receipt of the sample from the
field the following procedure should
be followed:
1. Remove the filter folder from its
shipping envelope and examine the
Hi-vol Field Data Record (Figure 4.3)
to determine whether all data needed
to verify the sample and to calculate
the concentration have been provided.
Void the sample if data are missing
and unobtainable from the field
operator or if a sampler malfunction
(e.g., faceplate gasket leakage) is
evident.
2. Record the filter number on the
Hi-vol Field Data Record and on the
Laboratory Data Log (Figure 3.1).
3. Examine the shipping envelope.
If sample material has been dislodged
from the filter, recover as much as
possible by brushing it from the
envelope onto the deposit on the filter
with a soft camel's-hair brush.
4. Examine the filter. If insects are
embedded in the sample deposit,
remove them with Teflon-tipped
tweezers, but disturb as little of the
sample deposit as possible. If more
than 10 insects are observed, refer
the sample to the supervisor for a
decision to accept or reject it
5. Record the data verification, the
sample inspection, and removal of
insects under "Remarks" in the
Laboratory Data Log
5.2 Filter Equilibration
The following procedure should be
used to equilibrate the exposed filters
in a conditioning environment for 24
h; up to 48 h may be needed for very
damp filters.
1 Use an eqilibration chamber with
a desiccant or an environmentally
controlled weighing room to maintain
an RH of <50 percent at 1 5° and
30°C (59° to 86°F) An air-conditioned
room may be used for equilibration if
it can be maintained at an RH of
<50% that is constant within +5%
and an air temperature between 15°
and 30°C that is constant within
+3°C (5°F) while the filters are
equilibrating A convenient working
RH is 40 percent. Keep a hygrometer
in the room
2. Check the RH daily
3 Record the hygrometer readings
and any equilibration chamber
malfunctions, discrepancies, or
maintenance in the Laboratory Data
Log.
5.3 Gravimetric Analysis
A balance check should be
performed as specified in Subsection
2 1
1 Weigh the exposed filters to the
nearest milligram (mg) on the
analytical balance.
2 Weigh the filters in the
conditioning environment if practical;
if not, be sure that the analytical
balance is as close as possible to the
conditioning chamber where it is
relatively free of air currents and
where it is at or near the temperature
of the chamber. Weighing should take
place within 30 seconds after
removing filters from the equilibration
chamber
3. Record the weight in the
Laboratory Data Log and on the High
Volume Field Data Record.
Table 5.1. Activity Matrix for Analysis of Samples
Activity Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
Documentation verification
and sample inspection
Filter equilibration
Gravimetric analysis
Complete documentation;
no evidence of malfunction
or sample loss; <10 insects
in sample
Controlled environment for
>24 h; RH <50% within
±5%; temperature constant
within ±3°Cat 15°to30°C
(59° to 86°FJ
Indicated weight obtained
to nearest milligram within
30 s after removal from
equilibration chamber
Visually check all samples
and documentation.
For each sample, observe
room or chamber conditions
and equilibration period.
Observe filter weighing
Void the sample
Repeat equilibration for 24
h at properly controlled
conditions
Report to supervisor;
reweigh after equilibration
for 24 h at controlled
conditions.
-------
Jan. 1983
Section 2.2,6
6.0 Calculations of TSP Concentrations and Data Reporting
A matrix summarizing the quality
control activities for the calculations
and the data-reporting requirements
is presented in Table 6 1
6.1 TSP Concentration
Equation 6-1 should be used to
calculate the total air volume sampled
V = Qsto t Equation 6-1
where
V = Total air volume sampled, m
standard volume units, std m3;
Qstd = average standard flow rate, std
mVmm;
t = samplmg time, mm
Equation 6-2 should be used to
calculate the TSP sample
concentration.
= (Wt:W,)106
V
Equation 6-2
where
TSP = concentration of TSP, /vg/std
m3,
Wi = weight of exposed filter, g
W, = tare weight of filter, g
All original calculations should be
recorded in the Laboratory Data Log
(Figure 3.1).
6.2 Data Documentation
and Reporting
All daily concentration levels should
be recorded m micrograms per
standard cubic meter (/yg/std m3),
with the required identifying
information, on the SAROAD Daily
Data form (Figure 6.1). See AEROS
Users Manual, OAQPS No. 1.2-039,
for detailed instructions.
Table 6.1.
ctivity
Activity Matrix for Calculations and Data Reporting
Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
Sample volume and
concentration
Data documentation and
reporting
All needed data available
Complete documentation
for calculation of concen-
tration; all sample and data
identification numbers
matched; no evidence of
malfunction or sample loss;
all needed data available
Visually check data records
for each sample.
Visually check data record
and data log for each
sample.
Void the sample.
Void the sample.
-------
Section 2.2.6
Jan. 1983
24 -Hour or Greater Sampling Interval
f^l 5>r?e/fer Ibun Pollution Control
1 Agency
City Name
State
Area
Site
V
(*
0
1\0
0
0
o
!
Site Address
23456789 10
Agency Project Time Year
Month
Project
7
7
6
Time Interval
1 1
12 13
14
15 16 17 18
7
ISP
Name
PARAMETER
Code
Day St Hr
19 20 21 2
|
0
0
1
23
o
28
2
0
1
0
1
24
/
29
33
l\0
2
5 26
O
!_/_
27
/
O
30 31 32
34 35 36
0
o
o
o
7
Cf
^
5
Name
PARAMETER
Code
37 38 39
40
41
42 43 44 45 46
47 48 49 50
Name
PARAMETER
Code
51 52 53 54 55
1
56 57 58 59 60
61 62 63 64
Name
PARAMETER
Code
65 66
70 71
75
57 68 69
72 73 74
76 77 78
{
\
DP- 43210
Figure 6.1 • SAROAD daily data form.
43210
43210
4 3 2 1 U
-------
Jan. 1983
Section 2.2.7
7.0 Maintenance
Scheduled or preventive
maintenance of the sampling
equipment reduces voided samples,
downtime, and remedial maintenance
Because the sampling equipment is
operated only intermittently, the
frequency of maintenance is a
function of the actual hours of use.
Normally, two or three preventive
maintenance activities are required
each year When possible,
maintenance is best performed in the
laboratory rather than in the field.
Motors on which maintenance has
been performed can then be carried to
the field for installation and
calibration. Table 7 1 at the end of
this section summarizes the quality
assurance activities of major
maintenance checks. All maintenance
activities should be recorded in a log
book
7.1 Sampler Motor
Motor brushes usually require
replacement after 400 to 500 h of
operation at normal line voltage (115
V) The procedure is as follows.
1. Replace the brushes before they
are worn to the point that
damage can occur to the
commutator of the Hi-Vol motor
The optimum replacement
interval must be determined from
experience
2. Follow the manufacturer's
instructions for replacing the
brushes.
3. Recalibrate the high-volume
sampler after the brushes are
replaced Do not recalibrate the
motor until after an initial break-
in period for the proper seating
of the brushes against the
armature; this period usually
requires running the sampler for
several hours against a
resistance equivalent to a clean
filter or a No. 18 calibration
plate.
4. Refer to the flow diagram in
Figure 7.1 for the various steps
required for motor maintenance
5. Record all sampler maintenance
operations (with dates performed
and the operator's initials) in the
sampler log book and on a
gummed label (Figure 7 2)
attached to the sampler
7.2 Faceplate Gasket
A worn faceplate gasket is
characterized by a gradual blending of
Open the Motor Housing
Remove Motor
Inspect Armature-
I
11 Bad
•Replace Armature
Change Brushes
• Check Motor •
If Good
Reassemble
Final Test
Field
Calibration
If Bad
Remove
Usable Parts
Discard Motor
Figure 7.1. Flow diagram for high volume sampler motor maintenance
the interface between the collected
participates and the clean filter
border Any decrease in the sharpness
of this interface indicates the need for
a new gasket.
1 Remove the old gasket with a
knife.
2. Clean the surface properly.
3 Seal a new gasket to the
faceplate with rubber cement or
double-sided adhesive tape.
Hi-vol motor number.
Site location
Last maintenance
Last calibration
Checked by
Next maintenance due
Next calibration due
Figure 7.2. Example of a gummed label
for a high-volume sampler.
4. Record all gasket replacements
with dates and operator's initials in
the sampler log book
7.3 Rotameter
1. Clean and recalibrate the
rotameter of a sampler when the float
behaves erratically or when moisture
or foreign matter is detected in the
rotameter.
2. Clean the rotameter prior to
routine calibration (alcohol is a
satisfactory cleaning solvent).
3. Refer to the flow diagram (Figure
7.3) for the required maintenance
steps.
7.4 Sampling Head
Leaks in the sampling head occur
infrequently. The welded seams and
the condition of the guide pins on the
top surface of the head should be
visually checked initially. Should a
-------
Section 2.2.7
Jan. 1983
Disassemble
\
leai
\
sm/i
*
\sen
\
Clean
Examine
Reassemble
Figure 7.3.
Calibrate
Maintenance sequence for
rotameter
defect be suspected, the following
procedure should be followed'
1 Assemble the sampling head to
the motor
2 Install a filter for resistance
3 Apply a soap solution to the
suspect problem area
4 Disassemble the sampling head.
5 Examine the inside of the head
for soap bubbles
6 Repair or discard the sampling
head if a leak is indicated by
soap solution being inside of the
head
7.5 Motor Gaskets
Two gaskets are used with each
sampler motor The top rubber gasket
is approximately 3/16-in. thick and
the bottom foam rubber gasket is
approximately 3/4-in. thick
1 Inspect both gaskets for wear or
deterioration
2. Replace if necessary.
7.6 Flow Transducer and
Recorder
Routine maintenance is not
required for this device. Should a
malfunction occur, replace the old
recorder with a new one.
Table 7.1. Activity Matrix for Maintenance
Equipment
Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
Sampler motor
Faceplate gasket
Rotameter
Motor gaskets
Sampling head
400-500 h of motor brush
operation; no ma/function
No leaks at the filter seal
No foreign materials;
stable operation
Leak-free fit
No leaks
Visually check upon receipt
and after each 400 h of
operation.
Visually check after each
sampling period.
Visually check at each
reading.
Visually check after each
400 h of operation.
Visually check after each
400 h of operation.
Replace motor brushes;
perform other maintenance
as indicated.
Rep/ace the gasket.
Clean; replace if damaged.
Replace gaskets.
Replace sampling head.
-------
Jan. 1983
Section 2.2.8
8.0 Auditing Procedure
An audit is an independent
assessment of the accuracy of data
Independence is achieved by having
the audit made by an operator other
than the one conducting the routine
measurements and by using audit
standards and equipment different
from those routinely used in
monitoring. The audit should be a true
assessment of the accuracy of the
measurement process under normal
operation—that is, without any special
preparation or adjustment of the
system Routine quality assurance
checks by the operator are necessary
for obtaining good quality data, but
they are not part of the auditing
procedure.
Three performance audits and one
systems audit are detailed in
Subsections 8.1 and 8.2. These audits
are summarized in Table 8 2 at the
end of this section. See Sections
2.0.11 and 2 0 12 of this volume for
detailed procedures for systems audits
and performance audits, respectively
Proper implementation of an
auditing program serves a two-fold
purpose, to ensure the integrity of the
data and to assess the accuracy of the
data A technique for estimating the
accuracy of the data is given in
section 2.0 8 of this volume
8.1 Performance Audits
Performance audits conducted by
another operator/analyst provide a
quantitative evaluation of the quality
of the data produced by the total
measurement system (sample
collection, sample analysis, and data
processing). Performance audits of
three individual portions of the total
measurement system are
recommended
1. Flow rate calibration
2. Exposed filter reweighmg
3. Data processing.
8.1.1 Audit of Flow Rate Calibration -
The frequency of audits of the flow
rate depends on the use of the data
(e.g., for PSD3 air monitoring or for
SLAMS"). It is recommended that the
flow rate of each high-volume
sampler be audited each quarter. Any
type flow-rate transfer device
acceptable for use in calibration of
high-volume samplers may be used as
the audit flow-rate reference
standard, however, the audit standard
must be different from the standard
used to calibrate the high-volume
samplers. The audit standard must be
calibrated with a positive-
displacement standard volume meter
(i.e , Roots meter) traceable to the
National Bureau of Standards See
Subsection 2 2 for procedures used to
certify flow rate transfer standards
With the audit device in place, the
high-volume sampler should be
operated at its normal flow rate The
differences in flow rate (in std
mVmin) between the audit flow
measurement (X) and the flow
indicated by the sampler's normal
flow indicator (Y) are used to calculate
accuracy as described in Section 208
of this volume
Great care must be taken in
auditing high-volume samplers having
flow regulators because the
introduction of the audit device can
cause abnormal flow patterns at the
point of flow sensing. For this reason,
the orifice of the flow audit device
must be used with a normal glass
fiber filter in place (and without
resistance plates) in auditing flow-
regulated high-volume samplers, or
other steps should be taken to assure
that flow patterns are not disturbed at
the point of flow sensing
Detailed procedures and forms used
to perform flow rate audits are given
in Section 2 0.1 2 of this volume
8.1.2 Audit of Exposed Filter
Reweighing - To avoid possible loss of
volatile components, exposed filters
should be weighed, including any
necessary reweighmg, as soon after
collection and equilibration as
practical. Thus, it may be impossible to
have lot sizes of more than 10 or 20
exposed filters. The procedure is as
follows.
1 Select randomly and reweigh
four re-equilibrated filters out of
every group of 50 or less. (This
would mean 100 percent
checking if four or fewer exposed
filters were weighed at one
time). For groups of 50 to 100,
reweigh 7 from each group
These suggested starting
frequencies may be altered,
based on experience and data
quality Decrease the frequency if
past experience indicates that
the data are of good quality, or
increase it if the data are of poor
quality. It is more important to be
sure that the sample is
representative of the various
conditions that may influence
data quality than to adhere to a
fixed frequency
2 Reweigh all filters in a lot if any
audit weight differs by more than
±5 0 mg from the original
weight.
3 Accept the lot with no change if
all audits are within ±5 0 mg of
the originals
4 Record the original and the audit
weights in milligrams (mg) on an
X-and-R chart (Figure 8 1). Plot
the difference (d), defined as
d = original weight - audit weight.
Equation 8-1
Tentative warning and control
limits of ±3 3 and ±5 0 mg,
respectively, are recommended
until sufficient data are obtained
to support an alteration of these
limits Out-of-control points
indicate the need for
recalibration of the balance
and/or improved operator
technique Do not increase the
limits, however, more stringent
limits may be established if
experience warrants
5 Forward the X-and-R chart to the
supervisor for review
6. Reweigh all of the remaining
exposed filters in the lot if the
balance requires recalibration or
the operation technique is
changed
8.1.3 Audit of Data Processing - for
convenience, the data processing
should be audited soon after the
original calculations have been
performed This allows corrections to
be made immediately. This also allows
for possible retrieval of additional
explanatory data from field personnel
when necessary The procedure is as
follows
1. Use the audit rate of Subsection
8 1 2
2. Starting with the raw data on the
dats form or on the flow rate
recorder chart, independently
compute the concentration (in /jg
TSP/m3) and compare it with the
corresponding concentration
reported on the SAROAD form. If
the mass concentration
computed by the audit check (fjg
TSP/m3)a does not agree (within
round-off error) with the original
-------
Section 2.2.8
Jan. 1983
•b
f
a
1
Qj "^
E U
i I
3 S
5
-------
Jan. 1983
Section 2.2.8
value (fjg TSP/m3)m, recheck all
samples in the lot and correct
them as necessary.
3. Record the audit values in the
data log, and report them along
with the original values to the
supervisor for review. The audit
value is always given as the
correct value, based on the
assumption that a discrepancy
between the two values is
always double-checked by the
auditor.
8.2 Systems Audit
A systems audit is an on-site
inspection and review of the quality of
the total measurement system (sample
collection, sample analysis, data
processing, etc.), and it is normally a
qualitative appraisal The procedure is
as follows
1 Conduct a systems audit on
receipt of a new monitoring
system and as appropriate
thereafter to audit possible
degradation or significant
changes in system operation
2 Use the preliminary checklist
given in Figure 8.2 Check the
questions for applicability to the
particular local, State, or Federal
agency.
See Sections 2.0.11 and 2.0 12 of
this volume for detailed procedures
and forms for systems audits and
performance audits, respectively.
Table8.2. Activity Matrix for Auditing Procedure
Audit
Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
Flow rate
Exposed filter reweighing
Data processing
Systems
Percentage difference,
X
within 37%
Audit weight = original
weight 35 mg
Audit concentration agrees
with original reported con-
centration within round-off
error
Method described in this
section of the Handbook
Once each quarter
Perform 7 audits/100
filters, or 4 audits/<50
filters; use analytical
balance, condition filters
for 24 h before weighing.
Independently repeat cal-
culation of JSP concentra-
tion from data record for 7
samples per 100 fminimum
of 4 per lot)
At beginning of a new
monitoring system and
periodically as appropriate,
observe procedures and
use checklist.
Recalibrate before
resuming sampling.
Re weigh all filters in the
lot
Recheck all calculations.
Initiate improved methods
and/or training programs.
-------
Section 2.2.8 4 Jan. 1983
Checklist for Use by Auditor for Hi-Vol Method
1 What type of hi-vol samplers are used in the network7 .
2 How often are the samplers run7 faj daily (b) once every 6 days (c) once every 12 days (d) other
3 What type of filter and how many are being used7
4 Are there any preexposure checks for pin holes or imperfections run on the filters7
5 What is the collection efficiency for your filters7
6 What /s the calibration procedure for the hi-vol sampler7
7 Which statement most closely estimates the frequency of flow rate calibration7 (a) once when purchased (b) once when
purchased, then after every sampler modification (cj when purchased, then at regular intervals thereafter
8 Are flow rates measured before and after the sampling period7
Yes A/o
9 Is there a loq book for each sampler for recording flows and times7 Yes No
JO Are filters conditioned before initial and final weighings7 If so. for how long7 At what
percentage humidity7 —
7 1 Is the balance checked periodically7 // so, how often7 With which standard weights7
12 How often are the hi-vol filters weighed7 .
How are the data from these weighings handled7
13 Are all weiqhinqs and serial numbers of filters kept in a log book at the laboratory7
14 What is the approximate time delay between sample collection and the final weighing7 days
Figure 8.2. Example of simplified checklist for use by auditor for hi-vol method
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Jan. 1983 1 Section 2.2.9
9.0 Assessment of Monitoring Data for Precision and Accuracy
9.1 Precision
For each monitoring network,
collocate an additional sampler at a
minimum of one site (two sites are
required for SLAMS4) as follows
1 Select a site with the highest
expected geometric mean
concentrations.
2 Locate the two high volume
samplers within 4 m of each
other, but at least 2 m apart to
preclude air flow interference.
3 Identify one of the two samplers
at the time of installation as the
sampler for normal routine
monitoring, identify the other as
the duplicate sampler
4. Be sure that the calibration,
sampling, and analysis procedure
are the same for the collocated
sampler as for all other samplers
in the network
5 Operate a collocated sampler
whenever its associated routine
sampler is operated.
6 Use the differences in the
concentrations (+g TSP/std m3)
between the routine and
duplicate samplers to calculate
the precision as described in
Section 2 0 8 of this Handbook.
Based on the results of a
collaborative test,5 percent difference
(Equation 8-1 of Section 208) should
not exceed 315% * An example
calculation is given m Section 2.0 8 of
this Handbook
9.2 Accuracy
The accuracy of the high-volume
method for measurement of TSP is
assessed by auditing certain portions
of the measurement process, as
described in Section 2.2.8 The
calculation procedure for single
instrument accuracy is given in
Section 2.0 8 of this volume of the
Handbook
•This 315% is calculated at the 997 probability
interval This means that if the two samplers do
agree, chances are less than 3 out of 1000 that a
difference larger than 15% will be observed
-------
Jan. 1983 1 Section 2.2.10
10.0 Recommended Standards for Establishing Traceability
For data of the desired quality to be
achieved, two considerations are
essential: (1) the measurement
process must be in a state of
statistical control at the time of the
measurement, and (2) the
combination of systematic errors and
random variation (measurement
errors) must yield a suitably small
uncertainty. Evidence of good-quality
data requires the performance of
quality control checks and
independent audits of the
measurement process; documentation
of the data on a quality control chart;
and the use of materials, instruments,
and measurement procedures that
can be traced to an appropriate
performance standard
Data must be routinely obtained by
repeating measurements of Standard
Reference samples (primary,
secondary, and/or working standards),
and a condition of process control
must be established. The working
calibration standards should be
traceable to standards of higher
accuracy, such as those listed here.
10.1 Recommended
Standards for Establishing
Traceability
1 Class-S weights of NBS
specifications are recommended for
the analytical balance calibration. See
Subsection 2.1 for details on balance
calibration checks.
2. A positive displacement
rootsmeter is recommended for
calibrating the flow rate transfer
standard that is used to calibrate the
high-volume sampler. See Subsection
2.6 for details on high-volume
sampler calibration.
3. A positive displacement
rootsmeter (including a resistance
plate) is recommended for calibrating
the device used to audit the high-
volume-sampler flow-rate calibration.
See Subsection 8.1 for details on
flow-rate calibration audits.
4. The elapsed-time meter, checked
semiannually against an accurate
timepiece, must be within 32
min/day.
-------
Jan. 1983
Section 2.2 1 1
11.0 Reference Method1
Appendix B—Reference
Method for the Determination
of Suspended Particulate
Matter in the Atmosphere
(High-Volume Method)
1.0 Applicability.
1.1 This method provides a
measurement of the mass
concentration of total suspended
paniculate matter (TSP) in ambient air
for determining compliance with the
primary and secondary national
ambient air quality standards for
paniculate matter as specified in §
50 6 and § 50.7 of this chapter. The
measurement process is
nondestructive, and the size of the
sample collected is usually adequate
for subsequent chemical analysis
Quality assurance procedures and
guidance are provided in Part 58,
Appendixes A and B, of this chapter
and in References 1 and 2
2.0 Principle.
2.1 An air sampler, properly located
at the measurement site, draws a
measured quantity of ambient air into
a covered housing and through a filter
during a 24-hr (nominal) sampling
period The sampler flow rate and the
geometry of the shelter favor the
collection of particles up to 25-50 +m
(aerodynamic diameter), depending on
wind speed and direction (3) The
filters used are specified to have a
minimum collection efficiency of 99
percent for 0 3 +m (OOP) particles
(see Section 7 1 4)
2.2 The filter is weighed (after
moisture equilibration) before and
after use to determine the net weight
(mass) gain The total volume of air
sampled, corrected to EPA standard
conditions (25°C, 760 mm Hg [101
kPa]), is determined from the
measured flow rate and the sampling
time. The concentration of total
suspended paniculate matter in the
ambient air is computed as the mass
of collected particles divided by the
volume of air sampled, corrected to
standard conditions, and is expressed
in micrograms per standard cubic
meter (+g/std m3) For samples
collected at temperatures and
pressures significantly different than
standard conditions, these corrected
concentrations may differ
substantially from actual
concentrations (micrograms per actual
cubic meter), particularly at high
elevations The actual paniculate
matter concentration can be calculated
from the corrected concentration
using the actual temperature and
pressure during the sampling period
3.0 Range.
3.1 The approximate concentration
range of the method is 2 to 750
+g/std m3 The upper limit is
determined by the point at which the
sampler can no longer maintain the
specified flow rate due to the
increased pressure drop of the loaded
filter This point is affected by
particle size distribution, moisture
content of the collected particles, and
variability from filter to filter, among
other things The lower limit is
determined by the sensitivity of the
balance (see Section 7 10) and by
inherent sources of error (see Section
6)
3.2 At wind speeds between 1 3 and
4 5 m/sec (3 and 10 mph), the high-
volume air sampler has been found to
collect particles up to 25 to 50 +m,
depending on wind speed and
direction (3) For the filter specified m
Section 7 1, there is effectively no
lower limit on the particle size
collected
4.0 Precision.
4.1 Based upon collaborative testing
the relative standard deviation
(coefficient of variation) for single
analyst precision (repeatability) of the
method is 3 0 percent. The
corresponding value for
interlaboratory precision
(reproducibility) is 3 7 percent. (4)
5.0 Accuracy.
5.1 The absolute accuracy of the
method is undefined because of the
complex nature of atmospheric
paniculate matter and the difficulty m
determining the "true" paniculate
matter concentration This method
provides a measure of paniculate
matter concentration suitable for the
purpose specified under Section 1 0.
Applicability.
6.0 Inherent Sources of
Error.
6.1 Airflow variation. The weight of
material collected on the filter
represents the (integrated) sum of the
product of the instantaneous flow rate
times the instantaneous particle
concentration Therefore, dividing this
weight by the average flow rate over
the sampling period yields the true
paniculate matter concentration only
when the flow rate is constant over
the period The error resulting from a
nonconstant flow rate depends on the
magnitude of the instantaneous
changes m the flow rate and in the
paniculate matter concentration
Normally, such errors are not large,
but they can be greatly reduced by
equipping the sampler with an
automatic flow controlling mechanism
that maintains constant flow during
the sampling period Use of a constant
flow controller is recommended *
6.2 Air volume measurement If the
flow rate changes substantially or
nonumformly during the sampling
period, appreciable error m the
estimated air volume may result from
using the average of the presamplmg
and postsamplmg flow rates Greater
air volume measurement accuracy
may be achieved by (1) equipping the
sampler with a flow controlling
mechanism that maintains constant
air flow during the sampling period,*
(2) using a calibrated, continuous flow
rate recording device to record the
actual flow rate during the sampling
period and integrating the flow rate
over the period, or (3) any other
means that will accurately measure
the total air volume sampled during
the sampling period. Use of a
continuous flow recorder is
recommended, particularly if the
sampler is not equipped with a
constant flow controller
6.3 Loss of volatiles. Volatile
particles collected on the filter may be
lost during subsequent sampling or
during shipment and/or storage of the
filter prior to the postsampling
weighing (5) Although such losses
are largely unavoidable, the filter
should be reweighed as soon after
sampling as practical.
6.4 Artifact paniculate matter.
Artifact paniculate matter can be
'Reproduced from 40 CFR 50, Appendix B, as
amended, December 6, 1982 (47 FR 54912)
-------
Section 2.2.11
Jan. 1983
formed on the surface of alkaline
glass fiber filters by oxidation of acid
gases in the sample air, resulting in a
higher than true TSP determination.
(6, 7) This effect usually occurs early
in the sample period and is a function
of the filter pH and the presence of
acid gases It is generally believed to
account for only a small percentage of
the filter weight gain, but the effect
may become more significant where
relatively small particulate weights
are collected.
6.5 Humidity. Glass fiber filters are
comparatively insensitive to changes
in relative humidity, but collected
particulate matter can be hygroscopic.
(8) The moisture conditioning
procedure minimizes but may not
completely eliminate error due to
moisture.
6.6 Filter handling. Careful handling
of the filter between the presampling
and postsampling weighings is
necessary to avoid errors due to loss
of fibers or particles from the filter. A
filter paper cartridge or cassette used
to protect the filter can minimize
handling errors. (See Reference 2,
Section 2).
6.7 Nonsampled particulate matter.
Particulate matter may be deposited
on the filter by wind during periods
when the sampler is inoperative. (9) It
is recommended that errors from this
source be minimized by an automatic
mechanical device that keeps the filter
covered during nonsamplmg periods,
or by timely installation and retrieval
of filters to minimize the nonsampling
periods prior to and following
operation.
6.8 Timing errors. Samplers are
normally controlled by clock timers set
to start and stop the sampler at
midnight. Errors in the nominal
1,440-min sampling period may result
from a power interruption during the
sampling period or from a discrepancy
between the start or stop time
recorded on the filter information
record and the actual start or stop
time of the sampler. Such
discrepancies may be caused by (1)
poor resolution of the timer set-points,
(2) timer error due to power
interruption, (3) missetting of the
timer, or (4) timer malfunction. In
general, digital electronic timers have
much better set-point resolution than
mechanical timers, but require a
*At elevated altitudes, the effectiveness of
automatic flow controllers may be reduced
because of a reduction in the maximum sampler
flow
battery backup system to maintain
continuity of operation after a power
interruption. A continuous flow
recorder or elapsed time meter
provides an indication of the sampler
run-time, as well as indication of any
power interruption during the
sampling period and is therefore
recommended.
6.9 Recirculation of sampler
exhaust. Under stagnant wind
conditions, sampler exhaust air can be
resampled. This effect does not appear
to affect the TSP measurement
substantially, but may result m
increased carbon and copper in the
collected sample. (10) This problem
can be reduced by ducting the
exhaust air well away, preferably
downwind, from the sampler.
7.0 Apparatus.
(See References 1 and 2 for quality
assurance information.)
Note.—Samplers purchased prior to
the effective date of this amendment
are not subject to specifications
preceded by (t).
7.1 Filter. (Filters supplied by the
Environmental Protection Agency can
be assumed to meet the following
criteria. Additional specifications are
required if the sample is to be
analyzed chemically.)
7.1.1 Size. 20.3 ± 0 2 x 25.4 ± 0.2
cm (nominal 8 x10 in).
7.1.2 Nominal exposed area: 406.5
cm3 (63 in2).
7.7.3 Material Glass fiber or other
relatively inert, nonhygroscopic
material. (8)
7.1.4 Collection efficiency: 99
percent minimum as measured by the
OOP test (ASTM-2986) for particles of
0.3 fjm diameter.
7.1.5 Recommended pressure drop
range 42-54 mm Hg (5.6-7.2 kPa) at
a flow rate of 1.5 std mVmin through
the nominal exposed area.
7.1.6 pH: 6 to 10. (11)
7.7.7 Integrity: 2.4 mg maximum
weight loss. (11)
7.1.8 Pinholes: None.
7.1.9 Tear strength: 500 g minimum
for 20 mm wide strip cut from filter in
weakest dimension. (See ASTM Test
D828-60).
7.7.70 Brittleness: No cracks or
material separations after single
lengthwise crease.
7.2 Sampler. The air sampler shall
provide means for drawing the air
sample, via reduced pressure, through
the filter at a uniform face velocity.
7.2.7 The sampler shall have
suitable means to:
a. Hold and seal the filter to the
sampler housing.
b. Allow the filter to be changed
conveniently.
c. Preclude leaks that would cause
error in the measurement of the
air volume passing through the
filter.
d. (t)Manually adjust the flow rate
to accommodate variations in filter
pressure drop and site line
voltage and altitude The
adjustment may be accomplished
by an automatic flow controller
or by a manual flow adjustment
device Any manual adjustment
device must be designed with
positive detents or other means
to avoid unintentional changes
in the setting.
7.2.2 Minimum sample flow rate,
heavily loaded filter: 1.1 mVmin (39
ftVminJ.ft
7.2.3 Maximum sample flow rate,
clean filter: 1.7 mVmin (60
ftVmin).tt
7.2.4 Blower Motor: The motor must
be capable of continuous operation for
24-hr periods.
7.3 Sampler shelter.
7.3.1 The sampler shelter shall-
a. Maintain the filter in a horizontal
position at least 1 m above the
sampler supporting surface so
that sample air is drawn
downward through the filter.
b. Be rectangular in shape with a
gabled roof, similar to the design
shown in Figure 1.
c. Cover and protect the filter and
sampler from precipitation and
other weather.
d. Discharge exhaust air at least
40 cm from the sample air inlet.
e. Be designed to minimize the
collection of dust from the
supporting surface by
incorporating a baffle between
the exhaust outlet and the
supporting surface.
(t) See note at beginning of Section 7
ttThese specifications are in actual air volume
units to convert to EPA standard air volume
units, multiply the specifications by (Pb/Pstu)
(298/T) where Pb and T are the barometric
pressure in mm Hg (or kPa) and the temperature
in K at the sampler, and P.w is 760 mm Hg (or
101 kPa)
-------
Jan. 1983
Section 2.2.11
Baffle
Figure 1. High-volume sampler in shelter
7.3.2 The sampler cover or roof
shall overhang the sampler housing
somewhat, as shown in Figure 1, and
shall be mounted so as to form an air
inlet gap between the cover and
the sampler housing walls tThis
sample air inlet should be approxi-
mately uniform on all sides of the
sampler. tThe area of the sample air
inlet must be sized to provide an ef-
fective particle capture air velocity of
between 20 and 35 cm/sec at the re-
commended operational flow rate. The
capture velocity is the sample air flow
rate divided by the inlet area mea-
sured in a horizontal plane at the
lower edge of the cover, fldeally, the
inlet area and operational flow rate
should be selected to obtain a capture
air velocity of 25 ±2 cm/sec
7.4 Flow rate measurement devices.
7.4.1 The sampler shall incorporate
a flow rate measurement device
capable of indicating the total sampler
flow rate. Two common types of flow
indicators covered in the calibration
procedure are (1) an electronic mass
flowmeter and (2) an orifice or orifices
located in the sample air stream
together with a suitable pressure
indicator such as a manometer, or
aneroid pressure gauge. A pressure
recorder may be used with an orifice
to provide a continuous record of the
flow Other types of flow indicators
(including rotameters) having
comparable precision and accuracy
are also acceptable.
7.4.2 fThe flow rate measurement
device must be capable of being
calibrated and read in units
corresponding to a flow rate which is
readable to the nearest 0.02 std
mVmm over the range 1.0 to 1.8 std
mVmm
7.5 Thermometer, to indicate the
approximate air temperature at the
flow rate measurement orifice, when
temperature corrections are used.
7.5.1 Range: -40° to +50°C (223-
323 K).
7.5.2 Resolution- 2° C (2 K).
7.6 Barometer, to indicate
barometric pressure at the flow rate
measurement orifice, when pressure
corrections are used
7.6.1 Range: 500 to 800 mm Hg
(66-106 kPa).
7.5.2 Resolution: ±5 mm Hg (0.67
kPa).
7.7 Timing/control de vice.
7.7.1 The timing device must be
capable of starting and stopping the
sampler to obtain an elapsed run-time
of 24 hr ±1 hr (1,440 ±60 mm).
7.7.2 Accuracy of time setting: ±30
mm, or better. (See Section 6 8).
7.8 Flow rate transfer standard,
traceable to a primary standard. (See
Section 9.2).
7.8.1 Approximate range: 1.0 to 1.8
mVmin.
7.8.2 Resolution 0.02 mVmin.
7.8.3 Reproducibility: ±2 percent (2
times coefficient of variation) over
normal ranges of ambient
temperature and pressure for the
stated flow rate range. (See Reference
2, Section 2.)
7.5.4 Maximum pressure drop at
1.7 std mVmin; 50 cm H20 (5 kPa).
7.5.5 The flow rate transfer
standard must connect without leaks
to the inlet of the sampler and
measure the flow rate of the total air
sample
[Corrected by 48 FR 17355, April 22,
1983]
7.8.6 The flow rate transfer
standard must include a means to
vary the sampler flow rate over the
range of 1.0 to 1.8 mVmin (35-64
ftVmm) by introducing various levels
of flow resistance between the
sampler and the transfer standard
inlet.
7.8.7 The Conventional type of flow
transfer standard consists of: An
orifice unit with adapter that connects
to the inlet of the sampler, a
manometer or other device to
measure orifice pressure drop, a
means to vary the flow through the
sampler unit, a thermometer to
measure the ambient temperature,
and a barometer to measure ambient
pressure Two such devices are
shown in Figures 2a and 2b. Figure
2a shows multiple fixed resistance
plates, which necessitate disassembly
of the unit each time the flow
resistance is changed. A preferable
design, illustrated in Figure 2b, has a
variable flow restriction that can be
adjusted externally without
disassembly of the unit. Use of
conventional, orifice-type transfer
standard is assumed in the calibration
procedure (Section 9). However, the
use of other types of transfer
standards meeting the above
specifications, such as the one shown
in Figure 2c, may be approved; see
the note following Section 9.1.
7.9 Filter conditioning environment
7.9.1 Controlled temperature:
between 15° and 30° C with less
than ±3° C variation during
equilibration period.
[Corrected by 48 FR 17355, April 22,
1983]
7.9.2 Controlled humidity: Less than
50 percent relative humidity, constant
within ±5 percent.
7.10 Analytical balance.
7.10.1 Sensitivity: QA mg.
7.10.2 Weighing chamber designed
to accept an unfolded 20.3 x 25.4 cm
(8x10 in) filter.
7.11 Area light source, similar to X-
ray film viewer, to backlight filters for
visual inspection.
7.12 Numbering device, capable of
printing identification numbers on the
filters before they are placed in the
filter conditioning environment, if not
numbered by the supplier.
8.0 Procedure.
(See References 1 and 2 for quality
assurance information.)
8.1 Number each filter, if not
already numbered, near its edge with
a unique identification number.
-------
Section 2.2.11
Jan. 1983
Orifice Type Flow
Transfer Standards
Nonorifice Type Flow
Transfer Standard
Resistance Plates
Inserted Between
Orifice and
Flange Plate
to Change
Flow
Continuous
Flow Adjustment
V
Continuous
Flow Adjustment
riJ-7
Flow
Indicator
Manometer
2a Orifice Unit Using Fixed
Resistance Plates
2b Preferable Orifice Unit with
Externally Adjustable
Resistance.
2c Electronic Flowmeter with Externally
Adjustable Resistance.
Figure 2. Various types of flow transfer standards Note that all devices are designed to mount to the filter inlet area of the sampler
8.2 Backlight each filter and inspect
for pmholes, particles, and other
imperfections; filters with visible
imperfections must not be used.
8.3 Equilibrate each filter in the
conditioning environment for at least
24-hr
8.4 Following equilibration, weigh
each filter to the nearest milligram
and record this tare weight (W,) with
the filter identification number
8.5 Do not bend or fold the filter
before collection of the sample
8.6 Open the shelter and install a
numbered, preweighted filter in the
sampler, following the sampler
manufacturer's instructions During
inclement weather, precautions must
be taken while changing filters to
prevent damage to the clean filter and
loss of sample from or damage to the
exposed filter Filter cassettes that can
be loaded and unloaded in the
laboratory may be used to minimize
this problem (See Section 6.6).
[Corrected by 48 FR 17355, April 22,
1983]
8.7 Close the shelter and run the
sampler for at least 5 min to establish
run-temperature conditions.
8.8 Record the flow indicator
reading and, if needed, the barometric
pressure (Pa) and the ambient
temperature (Ta) see NOTE following
step 8 1 2). Stop the sampler
Determine the sampler flow rate (see
Section 10 1); if it is outside the
acceptable range (1.1 to 1.7 mVmin
[39-60 ftVmm]), use a different filter,
or adjust the sampler flow rate
Warning Substantial flow
adjustments may affect the calibration
of the orifice-type flow indicators and
may necessitate recalibration.
8.9 Record the sampler
identification information (filter
number, site location or identification
number, sample date, and starting
time)
8.10 Set the timer to start and stop
the sampler such that the sampler
runs 24-hrs from midnight to
midnight (local time).
8.11 As soon as practical following
the sampling period, run the sampler
for at least 5 min to again establish
run-temperature conditions.
8.12 Record the flow indicator
reading and, if needed, the barometric
Pressure (Pa) and the ambient
temperature (Ta).
Note.—No on site pressure or
temperature measurements are
necessary if the sampler flow
indicator does not require pressure or
temperature corrections (e.g., a mass
flowmeter) or if average barometric
pressure and seasonal average
temperature for the site are
incorporated into the sampler
calibration (see step 9.3.9). For
individual pressure and temperature
corrections, the ambient pressure and
temperature can be obtained by onsite
measurements or from a nearby
weather station. Barometric pressure
readings obtained from airports must
be station pressure, not corrected to
sea level, and may need to be
corrected for differences in elevation
between the sampler site and the
airport. For samplers having flow
recorders but not constant flow
controllers, the average temperature
and pressure at the site during the
sampling period should be estimated
from weather bureau or other
available data.
8.13 Stop the sampler and carefully
remove the filter, following the
sampler manufacturer's instructions.
-------
Jan. 1983
Section 2.2.11
Touch only the outer edges of the
filter. See the precautions in step 8.6.
8.14 Fold the filter in half
lengthwise so that only surfaces with
collected paniculate matter are in
contact and place it in the filter holder
(glassine envelope or manila folder).
8.15 Record the ending time or
elapsed time on the filter information
record, either from the stop set-point
time, from an elapsed time indicator,
or from a continuous flow record. The
sample period must be 1,440 ± 60
min. for a valid sample.
8.16 Record on the filter information
record any other factors, such as
meteorological conditions,
construction activity, fires or dust
storms, etc., that might be pertinent to
the measurement. If the sample is
known to be defective, void it at this
time.
8.17 Equilibrate the exposed filter in
the conditioning environment for at
least 24-hrs.
8.18 Immediately after equilibration,
reweigh the filter to the nearest
milligram and record the gross weight
with the filter identification number.
See Section 10 for TSP concentration
calculations.
9.0 Calibration.
9.1 Calibration of the high volume
sampler's flow indicating or control
device is necessary to establish
traceability of the field measurement
to a primary standard via a flow rate
transfer standard. Figure 3a illustrates
the certification of the flow rate
transfer standard and Figure 3b
illustrates its use in calibrating a
sampler flow indicator. Determination
of the corrected flow rate from the
sampler flow indicator, illustrated in
Figure 3c, is addressed in Section
10.1.
Note.—The following calibration
procedure applies to a conventional
orifice-type flow transfer standard and
an orifice-type flow indicator in the
sampler (the most common types). For
samplers using a pressure recorder
having a square-root scale. 3 other
acceptable calibration procedures are
k-
Orifice Transfer
Standard Calibration
1 Required determinations.
Vm t. 7,. P, and AW
Sampler Calibration
provided in Reference 12. Other types
of transfer standards may be used if
the manufacturer or user provides an
appropriately modified calibration
procedure that has been approved by
EPA under Section 2.8 of Appendix C
to Part 58 of this chapter.
9.2 Certification of the flow rate
transfer standard.
9.2.1 Equipment required: Positive
displacement standard volume meter
traceable to the National Bureau of
Standards (such as a Roots meter or
equivalent), stop-watch, manometer,
thermometer, and barometer
9.2.2 Connect the flow rate transfer
standard to the inlet of the standard
volume meter. Connect the
manometer to measure the pressure
at the inlet of the standard volume
meter. Connect the orifice manometer
to the pressure tap on the transfer
standard. Connect a high-volume air
pump (such as a high-volume sampler
blower) to the outlet side of the
standard volume meter. See Figure
3a.
Flow Measurement
During Sampling
2. Calculate flow of standard volume
fa-
P.M = 760 mm Hg or 101 k Pa
Flow Transfer
Standard
Manometer-
Primary Volume
Standard
Transfer Standard
Calibration Curve
Transfer
Standard
Manometer
Required determinations (see
Table 1 in step 9.3 9 for the
appropriate expression in-
volving I).
A/Y, T2. P2. and I
Flow Indicator
Calibration Curve
Expression
Involving I
1 Required determination
7"i Pa and I It or specific P
and T corrections).
Ill average barometric pressure
and seasonal average temperature
have been incorporated at
previous calibration )
Calibrated
Transfer
Standard
Sampler
3a
Sampler
Calibrated
Flow
Indicator
T3 P3|
3b
3c
Figure 3. Illustration of the 3 steps in the flow measurement process.
-------
Section 2.2.11
Jan. 1983
9.2.3 Check for leaks by temporarily
clamping both manometer lines (to
avoid fluid loss) and blocking the
orifice with a large-diameter rubber
stopper, wide cellophane tape, or
other suitable means. Start the high-
volume air pump and note any change
in the standard volume meter reading.
The reading should remain constant.
If the reading changes, locate any
leaks by listening for a whistling
sound and/or retightening all
connections, making sure that all
gaskets are properly installed.
9.2.4 After satisfactorily completing
the leak check as described above,
unclamp both manometer lines and
zero both manometers.
9.2.5. Achieve the appropriate flow
rate through the system, either by
means of the variable flow resistance
in the transfer standard or by varying
the voltage to the air pump. (Use of
resistance plates as shown in Figure
la is discouraged because the above
leak check must be repeated each
time a new resistance plate is
installed.) At least five different but
constant flow rates, even distributed,
with at least three in the specified
flow rate interval (1.1 to 1.7 mVmin
[39-60 ftVmin]), are required.
9.2.6 Measure and record the
certification data on a form similar to
the one illustrated in Figure 4
according to the following steps.
9.2.7 Observe the barometric
pressure and record as Pi (item 8 in
Figure 4).
9.2.8 Read the ambient temperature
in the vicinity of the standard volume
meter and record it as Ti (item 9 in
Figure 4).
9.2.9 Start the blower motor, adjust
the flow, and allow the system to run
for at least 1 min for a constant motor
speed to be attained.
9.2.10 Observe the standard volume
meter reading and simultaneously
start a stopwatch. Record the initial
meter reading (V,) in column 1 of
Figure 4.
9.2.11 Maintain this constant flow
rate until at least 3 m3 of air have
passed through the standard volume
meter. Record the standard volume
meter inlet pressure manometer
reading as AP (column 5 in Figure 4),
and the orifice manometer reading as
AH (column 7 in Figure 4). Be sure to
indicate the correct units of
measurement.
9.2.12 After at least 3 m3 of air
have passed through the system,
observe the standard volume meter
reading while simultaneously stopping
the stopwatch. Record the final meter
reading (Vf) m column 2 and the
elapsed time (t) in column 3 of Figure
4.
9.2.13 Calculate the volume
measured by the standard volume
meter at meter conditions of
temperature and pressures as Vm =
Vf - V,. Record in column 4 of Figure
4.
9.2.14 Correct this volume to
standard volume (std m3) as follows:
V8,d = Vm Pi-API^
Pstd Ti
where:
Vstd = standard volume, std m2;
Vm = actual volume measured by
the standard volume meter;
Pi = barometric pressure during
calibration, mm Hg or kPa;
AP = differential pressure at inlet to
volume meter, mm Hg or kPa;
Pstd = 760 mm Hg or 101 kPa;
T.,d=298K;
Ti = ambient temperature during
calibration, K.
Calculate the standard flow rate (std
mVmin) as follows:
Qstd = Ystd.
t
where:
Qstd = standard volumetric flow rate,
std mVmin
t = elapsed time, minutes.
Record Qstd to the nearest 0.01 std
mVmin in column 6 of Figure 4.
9.2.15 Repeat steps 9.2.9 through
9.2.14 for at least four additional
constant flow rates, evenly spaced
over the approximate range of 1.0 to
1.8 std mVmin (35-64 ftVmin).
9.2.16 For each flow, compute
V AH (Pi/P,,d) (298/T,)
(column 7a of Figure 4) and plot these
values against Qstd as shown in Figure
3a. Be sure to use consistent units
(mm Hg or kPa) for barometric
pressure. Draw the orifice transfer
standard certification curve or
calculate the linear least squares
slope (m) and intercept (b) of the
certification curve:
V AH (P,/P,,d) (298/T!)
= m Qstd + b. See Figures 3 and 4. A
certification graph should be readable
to 0.02 std mVmin.
9.2.17 Recalibrate the transfer
standard annually or as required by
applicable quality control procedures.
(See Reference 2.)
9.3 Calibration of sampler flow
indicator.
Note.—For samplers equipped with
a flow controlling device, the flow
controller must be disabled to allow
flow changes during calibration of the
sampler's flow indicator, or the
alternate calibration of the flow
controller given in 9.4 may be used.
For samplers using an orifice-type
flow indicator downstream of the
motor, do not vary the flow rate by
adjusting the voltage or power
supplied to the sampler.
9.3.1 A form similar to the one
illustrated in Figure 5 should be used
to record the calibration data
9.3.2 Connect the transfer standard
to the inlet of the sampler. Connect
the orifice manometer to the orifice
pressure tap, as illustrated in Figure
3b. Make sure there are no leaks
between the orifice unit and the
sampler.
9.3.3 Operate the sampler for at
least 5 minutes to establish thermal
equilibrium prior to the calibration.
9.3.4 Measure and record the
ambient temperature, T2, and the
barometric pressure, P2, during
calibration.
9.3.5 Adjust the variable resistance
or, if applicable, insert the appropriate
resistance plate (or no plate) to
achieve the desired flow rate.
9.3.6 Let the sampler run for at least
2 min to re-establish the run-
temperature conditions. Read and
record the pressure drop across the
orifice (AH) and the sampler flow rate
indication (I) in the appropriate
columns of Figure 5.
9.3.7 Calculate
V AH(P2/Pstd) (298/T2)
and determine the flow rate
at standard conditions (Qstd) either
graphically from the certification curve
or by calculating Qstd from the least
square slope and intercept of the
transfer standard's transposed
certification curve:
Q,,d = 1/m VAH(P2/Ps,d)(298/T2)-b.
Record the value of Qstd on Figure 5.
[Corrected by 48 FR 17355, April 22,
1983]
9.3.8 Repeat steps 9.3.5, 9.3.6, and
9.3.7 for several additional flow rates
distributed over a range that includes
1.1 to 1.7 std mVmin.
9.3.9 Determine the calibration
curve by plotting values of the
-------
Jan. 1983
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Jan. 1983
Section 2.2.11
appropriate expression involving I,
selected from Table 1, against Qstd.
The choice of expression from Table 1
depends on the flow rate
measurement device used (see
Section 7.4.1) and also on whether
the calibration curve is to incorporate
geographic average barometric
pressure (Pa) and seasonal average
temperature (Ta) for the site to
approximate actual pressure and
temperature. Where Pa and Ta can be
determined for a site for a seasonal
period such that the actual barometric
pressure and temperature at the site
do not vary by more than ±60 mm Hg
(8 kPa) from Pa or ±15° C from Ta
respectively, then using Pa and Ta
avoids the need for subsequent
pressure and temperature calculation
when the sampler is used. The
geographic average barometric
pressure (Pa) may be estimated from
an altitude-pressure table or by
making an (approximate) elevation
correction of — 26 mm Hg (— 3.46
kPa) for each 305 m (1,000 ft) above
sea level (760 mm Hg or 101 kPa).
The seasonal average temperature (Ta)
may be estimated from weather
station or other records. Be sure to
use consistent units (mm Hg or kPa)
for barometric pressure.
[Corrected by 48 FR 17355, April 22,
1983]
9.3.10 Draw the sampler calibration
curve or calculate the linear least
squares slope (m), intercept (b), and
correlation coefficient of the
calibration curve: [Expression from
Table 1] = m Qstd + b. See Figures 3
and 5. Calibration curves should be
readable to 0.02 std mVmin
9.3.11 For a sampler equipped with
a flow controller, the flow controlling
mechanism should be re-enabled and
set to a flow near the lower flow limit
to allow maximum control range. The
sample flow rate should be verified at
this time with a clean filter installed.
Then add two or more filters to the
sampler to see if the flow controller
maintains a constant flow; this is
particularly important at high altitudes
where the range of the flow controller
may be reduced
9.4 Alternate calibration of flow-
controlled samplers. A flow-controlled
sampler may be calibrated solely at its
controlled flow rate, provided that
previous operating history of the
sampler demonstrates that the flow
rate is stable and reliable In this
case, the flow indicator may remain
uncalibrated but should be used to
indicate any relative change between
initial and final flows, and the sampler
should be recalibrated more often to
minimize potential loss of samples
because of controller malfunction
9.4.1 Set the flow controller for a
flow near the lower limit of the flow
range to allow maximum control
range
9.4.2 Install a clean filter in the
sampler and carry out steps 9.3.2,
9.3.3, 9.3.4, 9.3.6, and 9 3.7.
9.4.3 Following calibration, add one
or two additional clean filters to the
sampler, reconnect the transfer
standard, and operate the sampler to
verify that the controller maintains the
same calibrated flow rate; this is
particularly important at high altitudes
where the flow control range may be
reduced
10.0 Calculations of TSP
Concentration
10.1 Determine the average sampler
flow rate during the sampling period
according to either 10.1.1 or 101 2
below.
10.1.1 For a sampler without a
continuous flow recorder, determine
the appropriate expression to be used
Table 1. Expressions for Plotting Sampler Calibration Curves
Type of sampler
flow rate measuring
device
Mass flowmeter
Orifice and *pressure
indicator
Rotameter, or orifice
and pressure
recorder having
square root scale3
For actual pressure
and temperature
corrections
Expression
I
For incorporation of
geographic average pressure and
seasonal average temperature
/
*This scale is recognizable by its nonuniform divisions and is the most commonly
available for high-volume samplers.
from Table 2 corresponding to the one
from Table 1 used in step 9.3 9 Using
this appropriate expression, determine
Qstd for the initial flow rate from the
sampler calibration curve either
graphically or from the transposed
regression equation
Qstd =i- ([Appropriate expression from
m Table 2]—b)
Similarly, determine Qstd from the final
flow reading and calculate the
average flow Qstd as one-half the sum
of the initial and final flow rates.
10.1.2 For a sampler with a
continuous flow recorder, determine
the average flow rate device reading,
I, for the period. Determine the
appropriate expression from Table 2
corresponding to the one from Table 1
used in step 9.3.9 Then using this
expression and the average flow rate
reading, determine Qstd from the
sampler calibration curve, either
graphically or from the transposed
regression equation
Qstd=l- ([Appropriate expression from
m Table 2]—b)
If the trace shows substantial flow
change during the sampling period,
greater accuracy may be achieved by
dividing the sampling period into
intervals and calculating an average
reading before determining CW
10.2 Calculate the total air volume
sampled as.
V-Qs,d x t
where:
V = total air volume sampled, in
standard volume units, std
m3/;
Qstd - average standard flow rate,
std mVmin,
t = samplmg time, min.
[Corrected by 48 FR 17355, April 22,
1983]
10.3 Calculate and report the
paniculate matter concentration as:
TSP=(W,-W,)x106
V
where:
TSP = mass concentration of total
suspended paniculate matter,
fjg/std m3;
W, = initial weight of clean filter,
g;
W( = final weight of exposed filter, g
V = air volume sampled, converted
to standard conditions, std m3
106 = conversion of g to /ug
10.4 If desired, the actual particulate
matter concentration (see Section 2.2)
can be calculated as follows:
(TSP)a = TSP (P3/Pstd) (298/T3)
-------
Section 2.2.11
10
Jan. 1983
Table 2. Expressions for Determining Flow Rate During Sampler Operation
Expression
For use when geographic
average pressure
and seasonal average
temperature have been
incorporated into the
sampler calii. ation
Type of sampler
flow rate measuring
device
For actual pressure
and temperature
corrections
Mass flow meter
Orifice and pressure
indicator
Rotameter, or orifice
and pressure
recorder having
square root scale*
I
P3 \(298\
*-¥-
>.«A
298
I
1
"This scale is recognizable by its nonuniform divisions and is the most commonly
available for high-volume samplers.
where
(TSP)a = actual concentration at field
conditions, /ug/m3;
TSP = concentration at standard
conditions, /ug/std m3;
Pa = average barometric pressure
during sampling period, mm
Hg;
Paid = 760 mm Hg (or 101 kPa);
T3 = average ambient temperature
during sampling period, K.
11.0 References.
1. Quality Assurance Handbook for
Air Pollution Measurement Systems,
Volume I. Principles. EPA-600/9-76-
005. U.S. Environmental Protection
Agency, Research Triangle Park, North
Carolina 27711, 1976.
2. Quality Assurance Handbook for
Air Pollution Measurement Systems,
Volume II, Ambient Air Specific
Methods. EPA-600/4-77-027a. U.S.
Environmental Protection Agency,
Research Triangle Park, North
Carolina 27711, 1977.
3. Wedding, J.B., A.R. McFarland,
and J.F. Cernak. Large Particle
Collection Characteristics of Ambient
Aerosol Samplers. Environ. Sci.
Technol. 11:387-390, 1977.
4. McKee, H.C., et al. Collaborative
Testing of Methods to Measure Air
Pollutants, I. The High-Volume
Method for Suspended Particulate
Matter. J. Air Poll. Cont. Assoc., 22
(342), 1972..
5. Clement, R.E., and F.W. Karasek.
Sample Composition Changes in
Sampling and Analysis of Organic
Compounds in Aerosols. The Intern. J.
Environ. Anal. Chem., 7:109, 1979.
6. Lee, R.E., Jr., and J. Wagman. A
Sampling Anomaly in the
Determination of Atmospheric Sulfuric
Concentration, Am. Ind. Hygiene
Assoc. J., 27:266, 1966.
7. Appel, B.R., et al. Interference
Effects in Sampling Particulate Nitrate
in Ambient Air. Atmospheric
Environment, 13:319, 1979.
8. Tierney, G.P., and W.D. Conner.
Hygroscopic Effects on Weight
Determinations of Particulates
Collected on Glass-Fiber Filters, Am.
Ind. Hygiene Assoc. J., 28:363, 1967.
9. Chahal, H.S., and D.J. Romano,
High-Volume Sampling Effect of
Windborne Particulate Matter
Deposited During Idle Periods. J. Air
Poll. Cont. Assoc., Vol. 26 (885) 1976.
10. Patterson, R.K. Aerosol
Contamination from High-Volume
Sampler Exhaust. J. Air Poll. Cont.
Assoc., Vol. 30(169), 1980.
11. EPA Test Procedures for
Determining pH and Integrity of High-
Volume Air Filters, QAD/M-80.01.
Available from the Methods
Standardization Branch, Quality
Assurance Division, Environmental
Monitoring Systems Laboratory (MD-
77), U.S. Environmental Protection
Agency, Research Triangle Park, North
Carolina 27711, 1980.
12. Smith, F., P.S. Wohlschlegel,
R.S.C. Rogers, and D.J. Mulligan.
Investigation of Flow Rate Calibration
Procedures Associated with the High-
Volume Method for Determination of
Suspended Particulates. EPA-600/4-
78-047, U.S. Environmental
Protection Agency, Research Triangle
Park, North Carolina, June 1978.
-------
Jan. 1983 1 Section 2.2.12
12.0 References
1. 40 CFR 50, Appendix B, as
amended December 6, 1982 (47 FR
54912).
2. Quality Assurance Handbook for
Air Pollution Measurement Systems -
Volume I, Principles. EPA-600/9-76-
005, March 1976.
3. 40 CFR 58, Appendix B.
4. 40 CFR 58, Appendix A.
5. McKee, H.C., et al. Collaborative
Study of Reference Method for the
Determination of Suspended
Particulates in the Atmosphere (Hi-Vol
Method). PB 205-891, June 1971.
-------
Jan. 1983 1 Section 2.2.13
13.0 Data Forms
Blank data forms are provided on the
following pages for the convenience
of the Handbook user Each blank
form has the customary descriptive
title centered at the top of the page,
but the usual section-page
documentation in the top right-hand
corner of each page has been
replaced with a number in the lower
right-hand corner that will enable the
user to identify and refer to a similar
filled-in form in a text section For
example, Form TSP-1 1 indicates that
the form is Figure 1.1 of the TSP
method description. Any future
revisions of these forms can be
documented as 1.1 A, 1.1B, etc The
following data forms are included in
this section
Form Title
1.1 Procurement Log
2.3 Timer Calibration Log
2.4 Orifice Transfer Standard Certification Work Sheet
2 8 High-Volume Sampler Calibration Work Sheet
3.1 Laboratory Log for Total Suspended Particulate Data
3.2 Hi-Vol Field Data Form
4.6 Quality Control Chart
6.1 SAROAD Daily Data Form
8.2 Checklist for Use by Auditor for Hi-Vol Method
-------
Section 2.2.13
Jan. 1983
Procurement Log
Item description
Quantity
Purchase
order
number
Vendor
Date
Ordered
Received
Cost
Dispo-
sition
Comments
Quality Assurance Handbook TSP-1.1
-------
Jan. 1983
Section 2.2.13
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Jan. 1983
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Section 2.2.13
Jan. 1983
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— State Area Site . . _ . . . Code
Site Address 1 1 1 1 1 1 1 1 1 1 "">"<""""< <-**' woraicu fl 1 1 1 1
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-------
Jan. 1983
Section 2.2.13
Comments
Hi-Vol Data Record
Project
Station
Site and/ or Sampler No
Saroad Site Code
Sample Date
Filter No. —
Flow Reading initial
final -
Average Flow Rate .
Running Time Meter initial
final _
Total Sampler Time
Total Air Volume
Net TSP Weight
TSP Concentration
Optional
Temperature
initial .
final
average
Operator
. std m3
. fjg/std m3
Barometric Pressure
Quafity Assurance Handbook TSP-3.2
-------
Section 2.2.13
Jan. 1983
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-------
Jan 1983
Section 2.2.13
24-Hour or Greater Sampling Interval
SARD AD Daily Data Form
1 Agency
State
Area
Site
City Name
Site Address
23456789 10
Agency Project Time Year
Month
Pro/ect
Day St Hr
19 20 21 2
T/me Interval
Name
PARAMETER
Code
I
23 24 25 26 27
28 29 30 31 32
2 33 34 35 36
Name
PARAMETER
Code
37 38 39
42
40 41
43 44 45 46
47 48 49 50
,
11 12 13
14
Name
PARAMETER
Code
51 52 53 54 55
56
57 58 59
61 62 63
|
60
64
15 16 17 18
Name
PARAMETER
Code
65 66 67 68 69
70
71 72 73 74
75 76 77 78
DP-
43210
43210
43210 4 3 2 1 U
Quality Assurance Handbook TSP-6 1
-------
Section 2.2.13
10
Jan. 1983
Checklist for Use by Auditor for Hi-Vol Method
1 What type of hi-vol samplers are used in the network?
2 How often are the samplers run? (a) daily (bl once every 6 days fc) once every 12 days Id) other
3 What type of filter and how many are being used?
4 Are there any preexposure checks for pin holes or imperfections run on the filters?
5 What is the collection efficiency for your filters?
6. What is the calibration procedure for the hi-vol sampler?
7. Which statement most closely estimates the frequency of flow rate calibration? {a) once when purchased (b) once when
purchased, then after every sampler modification (c) when purchased, then at regular intervals thereafter -
8. Are flow rates measured before and after the sampling period?
Yes No
9. Is there a log book for each sampler for recording flows and times? Yes No
10 Are filters conditioned before initial and final weighings?
percentage humidity?
. If so. for how long?.
. At what
11 Is the balance checked periodically?.
. If so. how often?.
. With which standard weights?
12 How often are the hi-vol filters weighed?
How are the data from these weighings handled?
13 Are all weighings and serial numbers of filters kept in a log book at the laboratory?
14. What is the approximate time delay between sample collection and the final weighing? .
. days
Quality Assurance Handbook TSP-8.2
-------
Jan. 1983
United States
Environmental Protection
Agency
Section 2.6.0
Environmental Monitoring Systems
Laboratory
Research Triangle Park NC 27711
Research and Development
EPA-600/4-77-027a
Test Method
Section 2.6
Reference Method for the
Determination of Carbon
Monoxide in the Atmosphere
(Nondispersive Infrared
Photometry)
Outline
Section
Summary
Method Highlights
Method Description
1. Procurement of Equipment and
Supplies
2. Calibration of Equipment
3. Operation and Procedure
4. Data Reduction, Validation, and
-Reporting
5. Maintenance
6. Auditing Procedure
7. Assessment of Monitoring Data
for Precision and Accuracy
8. Recommended Standards for
Establishing Traceability
9. Reference Method
10. References
11. Data Forms
Number of
Documentation pages
2.6 1
26 1
2.6.1
2.6.2
2.6.3
2.6.4
2.65
2.6.6
2.6.7
2.6.8
2.69
2.6.10
2.6.11
4
6
6
3
2
4
1
3
1
12
Summary
Measurements of carbon monoxide
(CO) in ambient air are based on the
absorption of infrared radiation by CO
in a nondispersive photometer.
Infrared energy from a source is
passed through a cell containing the
gas sample to be analyzed, and the
quantitative absorption of energy by
CO in the sample cell is measured by
a suitable detector. The photometer is
sensitized to CO by employing CO gas
in either the detector or in a filter cell
in the optical path, thereby limiting
the measured absorption to one or
more of the characteristic
wavelengths at which CO strongly
absorbs. Optical filters or other means
may also be used to limit sensitivity of
the photometer to a narrow band of
interest. Various schemes may be
used to provide a suitable zero
-------
Section 2.6.0
Jan. 1983
reference for the photometer. The
measured absorption is converted to
an electrical output signal, which is
related to the concentration of CO in
the measurement cell.
An analyzer based on this principle
will be considered a Reference
Method only if it has been designated
as a Reference Method in accordance
with 40 CFR 53.
A current list of ail designated
Reference and Equivalent Methods is
maintained by EPA and updated
whenever a new method is
designated This list may be obtained
from any EPA Regional Office or from
the Environmental Monitoring
Systems Laboratory, Department E,
MD-77, Research Triangle Park,
North Carolina 27711 Moreover, any
analyzer offered for sale as a
Reference or Equivalent Method after
April 16, 1976, must bear a label or
sticker indicating that the EPA has so
designated it. Further discussion of
the concepts of Reference and
Equivalent Methods appears in
Section 2.0.4 of this Handbook.
Quality assurance procedures for
measuring CO with a nondispersive,
infrared radiation, automated
sampler are not instrument specific;
therefore, the following quality
assurance functions are applicable to
all CO analyzers designated as EPA
Reference Methods.
Method Highlights
This section presents procedures for
the Carbon Monoxide (CO) Reference
Method (Nondispersive Infrared
Photometry), which are intended to
serve as guidelines for the
development of agency quality
assurance programs. Because
recordkeepmg is critical in quality
assurance activities, example data
forms are included to aid in data
documentation. The blank data forms
(Section 2.6.11) may be used as they
are, or they may serve as a basis for
the preparation of forms more
appropriate to the individual agency;
the partially filled-m forms are
interspersed throughout the method
description to illustrate their uses.
Activity matrices at the end of
pertinent sections provide quick
reviews of the method description.
The CO method is summarized briefly
in the remainder of this section.
1. Procurement of Equipment and
Supplies
Section 2.6.1 gives the
specifications, criteria, and design
features of the equipment and the
supplies needed for the operation of
and quality assurance checks on a
continuous CO analyzer Selection of
the correct equipment and supplies is
a prerequisite of a quality assurance
program. This section provides a guide
for the procurement and the initial
checks of equipment and supplies.
2. Calibration of Equipment
Section 2.6.2 provides procedures
and forms to be used in performing a
multipoint calibration, and m
evaluating the calibration data.
Subsection 2 1 deals primarily with
minimum acceptable requirements for
standards to be applied to the
generation of CO concentrations.
Subsection 2.2 provides step-by-step
recommended calibration procedures
for a nondispersive infrared (NDIR) CO
analyzer, along with example
calculations The data form (Figures
2.1 and 2 2) is to be used in the
documentation of calibration data.
Dynamic instrument calibration is
essential for quality control
3. Operation and Procedure
Section 2.6 3 outlines the protocol
to be followed by the operator during
each site visit. To provide
documentation and accountability of
activities, the operator should compile
and fill out a checklist, similar to the
example in Figure 3 1 of Section
2.6.3, as each activity is completed.
Checks should include visual
inspection of the shelter, the sample
introduction system, the analyzer, and
the recorder Level 1 zero and span
checks must be carried out at least
once every 2 weeks; Level 2 checks
should be conducted between the
Level 1 checks at a frequency
established by the user. Span
concentrations for both levels should
be between 70 and 90 percent of the
measurement range. A one-point
precision check should be made every
2 weeks at a CO concentration
between 8 and 10 ppm. Data forms
similar to Figures 3.2 and 3 3 of
Section 2.6.3 should be used to
document the analyzer performance
checks. Routinely scheduled checks to
verify the operational status of the
monitoring system are essential in a
quality assurance program
4. Data Reduction. Validation, and
Reporting
Section 2.6.4 describes procedures
to be used for editing strip charts and
for data validation and reduction. Data
collected on strip charts serve no
useful function until they are
converted into meaningful units
(/yg/m3, ppm) applying to a specific
time period (e.g., hourly) through the
use of the calibration relationship.
These data must be transcribed into
an appropriate format such as that of
the SAROAD hourly data form.
5. Maintenance
Section 2.6.5 addresses the
recordkeeping and the scheduled
activities pertinent to preventive and
corrective maintenance A sample
maintenance log is shown in Figure
5.1. Preventive and corrective
maintenance are necessary to
minimize loss of air quality data due
to analyzer malfunctions and out-of-
control conditions.
6. Assessment of Data for Accuracy
and Precision
Section 2.6.6 discusses procedures
and forms for system and
performance audits. Multipoint
performance audits to be used to
assess the accuracy of the data
collection are discussed in Subsection
6.1.1; audit procedures are given in
Subsection 6.1.2; a data reduction
audit is discussed in Subsection 6.1.3;
and a system audit is discussed in
Subsection 6.2. Figure 6.1 presents
examples of audit summary and audit
calculation forms. Figure 6.2 is an
example checklist to be used by the
auditor.
Section 2.6.7 describes the
techniques for assessment of data for
accuracy and precision.
7. Reference Information
Section 2 6.8 discusses the
traceability of standards to established
standards of higher accuracy, a
prerequisite for obtaining accurate
data.
Sections 2 6.9 and 2.6.10 contain
the Reference Method and pertinent
references.
-------
Jan. 1983
Section 2.6.1
1.0 Procurement of Equipment and Supplies
b
m
Measurement of carbon monoxide
(CO) in ambient air requires basic
sampling equipment and peripheral
supplies; these include, but are not
limited to, the following:
1 Reference method CO analyzer
(NDIR) (Subsection 1 1 provides
information on obtaining an up-
to-date list of analyzers)
2. Strip chart recorder or data
logging system
3 Sampling lines
4. Sampling manifold
5. Calibration equipment
6. NBS-SRM or commercial CRM
calibration standard
7 Working calibration and audit
gases traceable to NBS or CRM
standard
8. Zero-air source
9. Spare parts and expendable
supplies
10. Record forms
11. Independent audit system
The person responsible for
purchasing materials should maintain
a log to record vendor names, part
umbers, prices, dates, and other
ertinent information. An example log
is shown in Figure 1 1. The log will
serve as a reference for future
procurement needs and as a tool for
planning budgets for future
monitoring programs. Quality
assurance activities for procurement
of equipment and supplies are
summarized in Table 1.2 at the end of
this section
1.1 The CO Analyzer (NDIR)
As stated in the Code of Federal
Regulations,1 each method for
measuring CO shall be either a
Reference or Equivalent Method when
the purpose is to determine
compliance with the National Ambient
Air Quality Standards (NAAQS). For
carbon monoxide, the Reference
Method is Nondispersive Infrared
Photometry (NDIR)
Although the NDIR analyzers
currently available for measuring CO
in ambient air are competitively
priced, price differences become
apparent when options to the basic
package are ordered. The buyer
should consult the list of designated
Reference and Equivalent Methods for
pproved options. An up-to-date list of
analyzers designated as reference or
Equivalent methods for CO is
available by writing to:
U.S. Environmental Protection Agency
Environmental Monitoring Systems
Laboratory
Department E, MD-77
Research Triangle Park, North
Carolina 27711
Available options include automatic
zero and span systems and complete
telemetry systems for transmitting
daily zero and span checks and real-
time data from the site to a central
location. For certain CO analyzers, the
automatic zero and span systems are
required to meet the EPA Reference
Method designation. Although options
can add convenience and flexibility,
their necessity and desirability must
be dictated by the availability of field
personnel, accessibility of the site,
and limitations of the budget.
When purchasing, the buyer should
request that the manufacturer supply
documented proof that the specific
analyzer performs within
specifications (Table 4 1, Section
2.0 4). The best proof is a strip chart
recording showing the specific
analyzer's zero drift, span drift,
electronic noise, risetime, falltime,
and lagtime. Acceptance of the
analyzer should be based on these
performance tests; once accepted, the
Reference and Equivalent analyzers
are warranted by the manufacturer to
operate within the required
performance limits for 1 year. The
strip chart will also serve as a
reference to determine whether the
performance of the analyzer has
deteriorated at a later date. The user
should reverify the performance
characteristics either during the initial
calibration or by using abbreviated
forms of the test procedures in the
ambient air monitoring Reference and
Equivalent Methods Regulations 2
1.2 Strip Chart Recorder
Recorders are commercially
available at a wide variety of prices
and specifications. Factors to be
considered in the purchase of a
recorder are:
1. Compatibility with the output
signal of the analyzer
2 A minimum chart width of 15
cm (6 in.) for the desired
accuracy in data reduction
3. A minimum chart speed of at
least 2.5 cm/h (1 in./h)
4. Response time
5. Precision and reliability
6. Flexibility of operating variables
(speed, range)
7. Maintenance requirements.
1.3 Sampling Lines and
Manifold
Wherever possible, sampling lines
and manifolds should be constructed
of Teflon or glass to minimize
degradation of the sample; however,
because of the relative inertness of
CO, other types of materials
(polypropylene, stainless steel) will
suffice if only CO is being measured
Sample residence time should be
minimized The use of a particle filter
on the sample inlet line of an NDIR
CO analyzer is optional on some
analyzers, and left to the discretion of
the user or the manufacturer. Use of
the filter should depend on the
analyzer's susceptibility to
interference, malfunction, or damage
due to particles.
1.4 Calibration Equipment
and Standards
The two acceptable methods for
dynamic multipoint calibration of CO
analyzers are:3
1. The use of individual certified
standard cylinders of CO for each
concentration needed.
2 The use of one certified standard
cylinder of CO, diluted as necessary
with zero-air, to obtain the various
calibration concentrations needed.
Both methods require the
following:
1. Pressure regulator(s) for CO
cylinder(s)
2 Flow controller
3. Flow meter
4. Mixing chamber (dynamic
dilution only)
5. Output manifold
6. Zero-air source
7. Calibration standard.
The equipment needed for calibration
can be purchased commercially, or it
can be assembled by the user. When
a calibrator or its components are
being purchased, certain factors must
be considered:
1. Traceability of the certified
calibration gases to an NBS-
SRM4 or an NBS/EPA-approved
commercially available Certified
Reference Material (CRM).
2. Accuracy of the flow-measuring
device (rotameter, mass flow
meter, bubble meter).
-------
Section 2.6.1
Jan. 1983
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Jan. 1983
Section 2.6.1
3. Maximum and minimum flows of
dilution air and calibration gases.
4. Ease of transporting the
calibration equipment from site
to site.
1.4.1 Pressure Regulator —
A pressure regulator will be
required for the CO calibration
standard cylinder If individual
cylinders are to be used for individual
calibration points, it is advisable to
procure regulators for each cylinder
Regulators must have a nonreactive
diaphragm and suitable delivery
pressure, A two-stage regulator with
inlet and delivery pressure gauges is
recommended. The supplier from
which the CO cylinders are to be
obtained should be consulted as to
the correct cylinder fitting size
required for the regulator
1.4.2 Flow Controller —
The flow controller can be any
device (valve) capable of adjusting and
regulating the flow from the
calibration standard If the dilution
method is to be used for calibration, a
second device will be required for the
zero-air. For dilution, the controllers
must be capable of regulating the flow
to ±1 percent
1.4.3 Flow Meter —
A calibrated flow meter capable of
measuring and monitoring the
calibration standard flow rate will be
required. If the dilution method is
used, a second flow meter will be
required for the zero-air flow. For
dilution, the flow meters must be
capable of measuring the flow with an
accuracy of ±2 percent
1.4.4 Mixing Chamber —
A mixing chamber is required only if
the calibrator concentrations are
generated by dynamic dilution of a CO
standard. The chamber should be
designed to provide thorough mixing
of CO and zero-air
1.4.5 Output Manifold —
The output manifold should be of
sufficient diameter to insure an
insignificant pressure drop at the
analyzer connection. The system
must have a vent designed to insure
atmospheric pressure at the manifold
and to prevent ambient air from
entering the manifold
1.4.6 Zero-Air Source —
A source of dry zero-air that is
verified to be free of contaminants
that could cause detectable responses
from the CO analyzer will be needed.
Zero-air containing <0 1 ppm CO may
be purchased in high-pressure
cylinders or generated with
commercially available clean air
systems The zero-air must contain
<0 1 ppm CO; some air cylinders sold
as ultrapure may actually contain 1 to
2 ppm CO The use of a catalytic
oxidizing agent such as Hopcalite on
any zero-air source would be prudent
1.4.7 Calibration Standard —
Both methods require CO standards
to be traceable to a National Bureau
of Standards Standard Reference
Material (NBS-SRM) or an NBS/EPA-
approved commercially available
Certified Reference Material (CRM)
(Section 268)
The CO standards must be in air
unless the dilution method is used.
For dilution, CO in nitrogen may be
used if the zero-air dilution ratio is not
less than 100 1 An acceptable
protocol for demonstrating the
traceability of commercial cylinder gas
to an NBS-SRM or CRM cylinder gas
is described in Section 2 0 7 of this
volume of the Handbook Table 1 1
lists these NBS-SRM's available for
CO monitoring
A list of gas manufacturers who
have approved CRM is available by
writing to
U S. Environmental Protection Agency
Environmental Monitoring Systems
Laboratory (MD-77)
Research Triangle Park, North
Carolina 27711
ATTN: List of CRM Manufacturers
1.5 Verification of
Calibration Equipment and
Gases
The user should reanalyze all
working standards used for calibrations
at least once every 6 months, as
specified in Section 2 0 7 of this
volume of the Handbook (particularly
Subsections 7 1 2 and 7 1 5 on
analysis and reanalysis of cylinder
gases) Flow-measuring devices
should be recalibrated by following
the procedures and schedules in
Section 2 1 2
1.6 Audit Equipment
All audit gas standards must be
traceable to an NBS-SRM or a
commercially available CRM, as
described by the protocol in Sections
262 and 2 0.7. All flow rates should
be measured by use of a calibrated
soap bubble meter or an equivalently
accurate device Personnel,
equipment, and reference materials
used in audits must be independent
from those normally used in
calibrations and operations
1.7 Spare Parts and
Expendable Supplies
In addition to the basic equipment
just discussed, an inventory of spare
parts and expendable supplies must
be maintained The manufacturer's
manual contains a maintenance
section describing the parts that
require periodic replacement and the
frequency of this replacement. Based
on these requirements, the manager
of the monitoring network can
determine which parts and the
quantity of each that should be
available at all times. Typical spare
parts and expendable supplies for CO
monitors are listed below; for more
specific requirements refer to the
manufacturer's manual
1 Particulate filters
2 Sampling lines
3 Pump diaphragms
4 Recorder chart paper
5 Recorder ink or pens
6 Record forms
7. Calibration gas
8 Spare fittings
1.8 Record Forms
Recordkeepmg is a critical part of all
quality assurance programs. Standard
forms similar to those in this manual
should be developed for each
individual program Three things to
consider in the development of record
forms are
1 Does the form serve a necessary
function?
2 Is the documentation complete?
3 Will the forms be filed in such a
manner that they can easily be
retrieved when needed?
Table 1.1.
NBS-SRM's for CO Monitors
SRM
1680b
1681b
2613
2614
Type
CO in nitrogen
CO in nitrogen
CO in air
CO in air
Vol/unit,
liters at
STP
870
870
870
870
Nominal CO
concentration,
ppm
500
1000
18.1
43.0
-------
Section 2.6.1
Jan. 1983
Table 1.2. Activity Matrix for Procurement of Equipment and Supplies
Equipment and
supplies
Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
NDIR analyzer
Strip chart recorder
Sampling lines and manifold
Calibration gases
Audit gases
Zero-air
Performance according to
specifications in Table 4.1,
Sec. 204
Compatible with output
signal of analyzer, recom-
mended chart width of 15
cm (6 in)
Constructed of Teflon or
glass
Traceable to an NBS-SRM
or a commercially available
CRM; ±2.0% of rated
concentration
Traceable to an NBS-SRM
or commercially available
CRM; ±2 0% of rated
concentration
<0.1 ppm CO
Manufacturer strip chart
recording of analyzer's
performance
V/sually observe upon
receipt
Visually observe upon
receipt
Upon receipt and monthly
thereafter for first 3 mo; if
concentration remains
stable, verify every 6th
month
As above
Check against analyzer
internal zero or another
source of zero-air known to
to be CO-free
Have the manufacturer
adjust and rerun the per-
formance checks
Return to supplier
Other types of materials
may be acceptable for CO
sampling
Return to supplier
As above
As above
-------
Jan. 1983
Section 2.6.2
2.0 Calibration of Equipment
The accuracy and validity of
measurement data recorded by air
monitoring equipment depend on the
quality assurance procedures used
The primary procedure is dynamic
calibration, which determines the
relationship between the observed
and the actual values of the variable
being measured.
In dynamic multipoint calibration,
gas samples of known concentrations
are introduced to an instrument to
derive a calibration relationship or to
adjust the instrument to a
predetermined sensitivity The
relationship is derived from the
instrumental responses to the
successive samples of known
concentrations A minimum of four
reference points and a zero point are
recommended to derive the
relationship. The "true" value of each
calibration gas must be traceable to
an NBS-SRM or a commercially
available CRM (Section 207)
Most present-day monitoring
systems are subject to drift and
variability of internal parameters, and
they cannot be expected to maintain
calibrations over long periods of time
Therefore, it is necessary that the
calibration relationship be dynamically
checked on a predetermined schedule.
Precision is determined by a one-point
check performed at least once every 2
weeks Network accuracy is determined
by a three-point audit performed at
least once each quarter. Zero and
span checks must be made to
document m-control conditions; these
checks are also used in data reduction
and validation.
Table 2.1 at the end of this section
summarizes the quality assurance
activities for calibration procedures
2.1 Calibration Gases
2.1.1 CO Standard —
The CO standards must be in air
unless the dilution method is used.
For dilution, CO in nitrogen may be
used if the zero-air dilution ratio is not
less than 100:1. All calibration gas
mixtures must be referenced against
an NBS-SRM or a commercially
available CRM (Section 2 0.7). The
steps required for comparing the
concentration of a commercial
working calibration standard to the
concentration of an NBS-SRM or a
CRM are described in Subsection 7.1
of Section 2.0.7. Subsections 7 1 4
and 7 1.5 describe the procedures for
verification and reanalysis of cylinder
gases The CO gas cylinders should be
recertified every 6 months The use of
aluminum cylinders will provide better
stability of CO standards
2.1.2 Dilution Gases —
Zero-air, verified to be free of
contaminants that would cause
detectable responses in the CO
analyzer, may be purchased in high-
pressure cylinders or generated with
commercially available clean air
systems Care must be exercised to
ensure that <0 1 ppm CO is present
in the zero air; some air cylinders sold
as ultrapure may actually contain 1 to
2 ppm CO Any zero air source used
must be verified to contain <0 1 ppm
CO. The use of a catalytic oxidizing
agent such as Hopcalite on any zero-
air source would be prudent Any zero
air passing through a catalytic oxidizer
must be free of water vapor
2.2 Calibration
The procedure for dynamically
calibrating the NDIR analyzer may be
found in 40 CFR 50,3 and in the
manufacturer's manual Essentially,
the procedure involves challenging
the analyzer with a minimum of four
CO concentrations and defining the
relationship between the
concentration and the analyzer
response Forms for recording
operational and calculation data have
been developed to aid in the
documentation of calibrations and
quality assurance checks
Documentation of all data on the
station, instrument, calibrator,
reference standard, and calibration
activity is of prime importance
because the validity of the data
collected by the monitor depends on
its calibration
2.2.1 Calibration Procedure —
The following calibration procedure
is based on dynamically diluting a
high CO concentration with zero-air.
An alternative procedure is to use
individual cylinders containing the
desired CO concentrations, which
eliminates the necessity of dilution
Any dynamic dilution system used
for calibration must be capable of
measuring and controlling flow rates
to within ±2 percent of the required
flow. Flow meters must be calibrated
under the conditions of use against a
reliable standard, such as a soap
bubble meter or a wet test meter All
volumetric flow rates should be
corrected to 25°C (77°F) and 760 mm
(29 92 in ) Hg If both the CO and the
zero-air flow rates are measured with
the same device under the same
conditions of temperature and
pressure, the STP correction factor in
the calibration equations can be
disregarded
The following step-by-step
procedure uses a data form (Figure
2 1) to aid m the collection and
documentation of calibration data The
calibration equations in Figure 2 1,
the CO calibration and linearity check
table, and the calibration relationship
plot in Figure 2 2 are given to
facilitate the systematic recording of
data derived during the calibration of
the NDIR CO analyzer. The user
should consult the manufacturer's
manual before beginning the
calibration because the zero and
calibration procedures and adjustments
differ from analyzer to analyzer
1 Record the official name and
address of the individual station. Note:
Where appropriate, the station name,
address, and SAROAD ID should be the
same as that on the hourly average
data form (Figure 4 1 of Section 2.6.4)
to help eliminate confusion on the
part of persons not familiar with the
station
2 Identify the analyzer being
calibrated by recording the
manufacturer's name, model, and
serial number
3 Identify the person performing
the calibration and give the date of
calibration
4 Identify the calibrator or dilution
system used If the system was
purchased, record the manufacturer's
name, model, and serial number, if
the system was assembled by the
user, assign it an identification
number so that calibrations can be
referenced to that particular
apparatus
5 Identify, by supplier and cylinder
number, the reference standard used;
record the concentration of calibration
gases determined by the user and the
cylinder pressure, provide a record of
NBS-SRM or CRM traceability for any
cylinder used in a calibration, and
include the date and the name of the
person who conducted the traceability
test Note Cylinders with pressures of
-------
Section 2.6.2
Jan. 1983
1. Station
Calibration Summary
2 Analyzer
North
Model
3 Calibration by
4 Calibrator mfr
Model
5 CO standard _
SM/rH
Date _
S/N
Concentration
Verified against NBS-SRM _
r CC /•*•(/ Cylinder pressure 5OO PS f
Date
6 Flow-measuring device
7. Barometric pressure
/fcss-PfcoJ
Traceability
meter-
f1\ t\/[
Shelter temperature
8 Analyzer's sample flow rate
9 Zero knob setting
Span knob setting
Calibration Equations
Equation 2-1
Fo or Fco = F (STP correction factor)
Equation 2-2
STP Correction factor = &? x 298
760 AT+273
Equation 2-3
[COjour =
Fo + Fco
Equation 2-4
% scale = [COW x TOO +
URL
Figure 2.1. Example of calibration data form
F = uncorrected flow rate for dilution air or CO standard gas, I/mm
F0 - flow rate of dilution air corrected to 25°C and 760 mm Hg, I/mm
Fco = flow rate of CO standard corrected to 25°C and 760 mm Hg,
I/mm
BP = barometric pressure, mm Hg
AT = temperature of gas being measured, °C
[COloui = concentration at the output manifold, ppm
[CO]sTo= concentration of the undiluted standard, ppm
Zco - recorder response to zero air
<200 psig should not be used for
calibration because gases in cylinders
may become unstable for some
concentrations at low pressures
(Section 2.0.7).
6. Identify the flow-measuring
device used, and document the
traceability of its accuracy.
7. Record the barometric pressure
and the shelter temperature before
the calibration.
8. Record the analyzer's sample
flow rate.
9. Record the zero and span knob
settings after the calibration so that
these settings can be used later to
determine changes in instrument
performance.
Figure 2.2 contains a CO calibration
and linearity check table and a graph to
facilitate the plotting of the calibration
data. The equations at the bottom of
Figure 2 1 are to be used to obtain the
entries in the table in Figure 2.2. The
detailed steps of the calibration
procedure are given below. Analyzer
responses in these steps refer to
recorder responses. The
manufacturer's instrument manual
should be consulted for analyzer-
specific calibration procedures.
1. Select the operating range of the
analyzer to be calibrated by referring
to the manufacturer's manual for the
ranges over which the analyzer is
considered to be a reference method.
2. Connect the recorder output
cable(s) of the analyzer to the input
terminals of the strip chart
recorder(s). All adjustments to the
analyzer should be based on the
appropriate strip chart readings. Note:
When data acquisition systems are
used to store and/or transmit data to
a base station, some provision must
be made to verify the accuracy of the
transmitted data. In these cases, a
voltmeter or recorder can be used to
take readings and to make
adjustments onsite A comparison
check must then be made between
signal outputs from the analyzer and
data received at the base locations.
3. Adjust the zero-air flow to the
-------
Jan. 1983
Section 2.6.2
Calibration
points
Zero
80% URL
1
2
3
1
FCC.
I/mm
(Ed 2- 1 & 2-2la
0.500
0.500
0.500
0-500
2
Fa
I/mm
lEa 2- 1 & 2-21
2.1*1-5
3.U7
5.150
Ili.OOO
3
[CO]OUT,
Pfim
/Eg 2-31
0
10
2>6
ZD
10
4
% scale
(Ecj 2-41
5%
ff5%
&5%
45%
73%
"Equations 2-1 through 2-4 are given in Figure 2 1 and in the text
o
Q.
«
c
<*
f*n
....
. .
.
...
: . . .
E! : : : : : : : : : : : : :
. : : : :
..... : 1 1 i . 1 1
_„_._,_ _ ___..._..
i
'
"
'
f
*
*
T '
H
T
' T
'
"
0 10 20 30 40 50
fCOJour, ppm
*h,p 2~ . O
tinnshin <_./ f^}
Slope (b) of calibration relationship
Intercept la) of calibration relationship
Figure 2.2. Example of calibration data form. (Linearity Check and Calibration Relationship)
-------
Section 2.6.2
Jan. 1983
analyzer; the flow must exceed the
total demand of the analyzer
connected to the output manifold to
ensure that no ambient air is pulled
into the manifold vent.
4. Allow the analyzer to sample the
zero air until a stable response is
obtained; adjust the analyzer zero
control to within ±0.5 ppm of zero
base line, and record the stable zero-
air response (% scale) under column 4
of the calibration table in Figure 2.2.
Note: Offsetting the analyzer zero
adjustment to +5% of scale is
recommended to facilitate observing
negative zero drift On most analyzers,
this should be done by offsetting the
recorder zero
5. Determine the 80 percent upper
range limit (URL) of the analyzer
Example: For an analyzer with an
operating range of 0 to 50 ppm, the
80 percent URL value would be 0.80
x 50, or 40 ppm
6 Adjust the CO flow from the
standard CO cylinder to generate a
CO concentration of approximately 80
percent of the URL Measure the CO
flow, correct it to STP, and record
under column 1 (Fco), on the 80
percent URL line.
Fco = F x (STP correction factor)
Equation 2-1
STP correction factor = BP x 298
760 AT + 273
Equation 2-2
where
Fco = flow rate of CO standard
corrected to STP, I/mm
F = uncorrected flow rate, l/min
BP = barometric pressure, mm Hg
AT = temperature of gas being
measured, °C
Note: If wet test meter or bubble
meter is used for flow measurement,
the vapor pressure of water at the
temperature of the meter must be
subtracted from the barometric
pressure.
Measure the dilution air flow,
correct it to STP, and record under
column 2 (FD).
FO = F x (STP correction factor)
7. Calculate the CO concentration
[C0]our using Equation 2-3.
fCOIsTPXFcO
[COJour = FD +Fco
Equation 2-3
Record this value on the 80% URL
line under column 3.
8. Calculate the required recorder
response for span adjust (80% URL)
using Equation 2-4.
x 100 I + ZCo
% scale = ([COlou
V URL
Equation 2-4
Allow the analyzer to sample until the
response is stable; adjust the analyzer
span until the required response is
obtained, and record the CO recorder
response on 80 percent URL line
under column 4. Note. If substantial
adjustments of the span control are
necessary, recheck the zero and span
adjustments by repeating steps 4 and
8.
9. After the zero and 80 percent
URL points have been set, without
further adjusting the instrument,
generate three approximately evenly
spaced points between zero and 80
percent URL by increasing the dilution
flow (Fo,) or by decreasing the CO
flow (Fco). For each concentration
generated, calculate the CO
concentrations (using Equation 2-3)
and record the results for each point
under the appropriate column in the
table in Figure 2.2.
10. On the blank graph of Figure
2.2, plot the analyzer responses
expressed in percent scale at the
recorder (y-axis) versus the
corresponding calculated
concentrations (x-axis) to obtain the
calibration relationship. Determine the
straight line of best fit by the method
of least squares (Volume I, Appendix J
of this Handbook) using a
programmed calculator or the
calculation data form (Figure 2.3).
Note: Because manual calculations
(using the data form) require
considerably more time than the use
of a programmed calculator, it is
suggested that the latter be used
when possible.
11. After determining the slope (b)
and the intercept (a) where the line
crosses the y-axis, draw the fitted line
as follows: On the y-axis, plot the y
intercept, a, use the equation Y = a +
bx to calculate the predicted Y value
using the 80 percent URL
concentration for the x value as the
second point on the graph. Draw a
straight line through these two points
to give a best-fit line, as shown in
Figure 2.4
12. After drawing the best-fit line,
determine if the analyzer response is
linear, that is, no calibration point
varies from the best-fit line by more
than 2 percent of full scale. Make a
simple test for linearity by plotting a
point 2 percent of scale above and 2
percent of scale below the point
where the best-fit line crosses the 40-
ppm level and the 10-ppm level, and
then draw a straight line through the
+2 percent points and one through the
-2 percent points (Figure 2.4). The two
lines (above and below the best-fit
line) define the limits between which
the calibration points can fall for the
calibration curve to be considered
linear. Points outside these limits
should be repeated to check for
calibration point errors; if the repeated
points still fall outside the limits,
consult the manufacturer's manual
to determine and correct the problem.
2.2.2 Calibration Frequency —
To ensure accurate measurements
of the CO concentrations, calibrate the
analyzer at the time of installation,
and then recalibrate it as specified in
the instrument manual or
1. No later than 3 months after the
most recent calibration or
performance audit. If
performance audit results are
satisfactory, recalibration must
be performed immediately.
2. After an interruption of more
than a few days in analyzer
operation, after any repairs that
might affect its calibration, after
physical relocation of the
analyzer, or after any other
indication (including excessive
zero or span drift) of possible
significant inaccuracy of the
analyzer. Following any of these
activities, a Level 1 zero and
span check should be made to
determine if recalibration is
necessary If the zero and span
drifts do not exceed the limits
(Table 9 1, Section 2.0.9,
Subsection 9.1.3), a calibration
need not be performed. If either
the zero or the span drift exceeds
its limit, investigate the cause of
the drift, take corrective action,
and calibrate the analyzer
-------
Jan. 1983
Section 2.6.2
Calibration
point
Zero
80% URL
1
2
3
Concentration.
ppm
X
O
HO
20
/O
X*
0
/bOO
900
100
/oo
Recorder
reading.
% scale
Y
5
85
(JS
45
25
Y*
Z5
122$
WZ5
2.0Z5
6xL5
xy
O
3
-------
Section 2.6.2
Jan. 1983
100
80
•g 60
8
1
I
40
20
Best-Fit calibration
line
Limits for instrument
linearity check. ±2%
0 10 20 30
[COJouT, ppm
Figure 2.4. Example of a CO calibration relationship
40
50
Table 2.1. Activity Matrix for Calibration Procedures
Calibration
activities
Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
Dilution gas
Span gases
Multipoint calibration
Zero-air free of contami-
nants (Sec. 2.0.7, Subsec.
7.1)
Cylinder gases certified to
NBS or CRM standard;
cylinder pressure >200
psig
According to calibration
procedure fSubsec. 2.2)
and data recorded (Figs 2.1
and 2.2)
Compare the new zero-air
against source known to be
free of contaminants
Assay against an NBS-
SRM or CRM semiannually
(Sec. 2.0.7)
Calibrate at least once,
quarterly; anytime a Level
1 span check indicates dis-
crepancy; after mainte-
nance that may affect the
calibration (Subsec. 2.2)
Return to supplier, or take
corrective action with
generation system as
appropriate
Working gas standard un-
stable, and/or measurment
method out of control;
take corrective action,
e.g., obtain new span gases
Repeat the calibration
-------
Jan. 1983
Section 2.6.3
3.0 Operation and Procedure
A routinely scheduled series of
checks to verify the operational status
of the monitoring system is an
essential part of the quality
assurance program. The operator
should visit the site at least once each
week, and he/she must make a Level
1 zero and span check on the analyzer
at least once every 2 weeks. The user
may decide on the frequency of any
Level 2 zero and span checks. In
addition, an independent precision
check between 8.0 and 10.0 ppm
must be carried out at least once
every 2 weeks.
Table 3.1 at the end of this section
summarizes the quality assurance
activities for routine operations
discussed in the following subsections.
To provide documentation and
accountability of activities, the field
operator should compile and fill out a
checklist as each activity is completed;
Figure 3.1 is an example checklist.
In Subsections 3.1 and 3 2,
reference is made to the sampling
shelter and sample inlet system. The
design and construction of these
components of the sampling system
are not within the scope of this
document, but an in-depth study of
these is provided in Reference 5.
3.1 Shelter
The shelter's role in quality
assurance is to provide a
temperature-controlled environment
in which the sampling equipment can
operate at optimum levels of
performance. The mean shelter
temperature should be between 22°
and 28°C (72° and 82°F). A
thermograph should be installed at the
shelter so that daily temperature
fluctuations can be continuously
recorded. Fluctuations greater than
±2°C (4°F) may cause the electronic
components of the analyzer to drift
and introduce error into the data;
thus, fluctuations outside of the
specifications should be identified,
and the data for the affected time
period should be flagged to indicate
possible discrepancies. Excess
vibrations will cause analyzer
fluctuations and should be minimized
where possible.
3.2 Sample Introduction
System
The sample introduction system
consists of an intake port, particulate
and moisture traps, a sampling
manifold, a blower, and a sampling
line to the analyzer As part of the
quality assurance program, the field
operator should inspect each of these
components for breakage, leaks, and
buildup of particulate matter or other
foreign materials, check for moisture
depostion in the sampling line or
manifold; and check the connection
between the sampling line and the
manifold Any component that is not
within tolerance should be cleaned or
replaced immediately (Section 2.0.2).
3.3 Recorder
During each visit to the monitoring
site, the field operator should check
the recorder against the following list:
1. Legibility of the ink trace
2. Ink supply in the reservoir
3. Chart paper supply
4. Chart speed control setting
5. Signal input range setting
6. Time synchronization Mark chart
with correct time and date
Any operational parameter that is not
within tolerance must be corrected
immediately.
3.4 Analyzer
The user should read thoroughly the
specific instructions in the
manufacturer's manual before
attempting to operate the analyzer
As part of the quality assurance
program, each site visit should include
a-visual inspection of the external
parameters of the analyzer, the zero
and span checks, and a biweekly
precision point check.
3.4.1 Visual Inspection —
The field operator should inspect
the external operating parameters of
the analyzer; these will vary from
instrument to instrument, but they
generally will include the following
1 Correct setting of flow meter and
regulators
2. Cycling of temperature control
indicators
3 Verification that the analyzer is
in the sampling mode rather than
in the zero or calibration modes
4. Zero and span potentiometers set
and locked at proper values.
3.4.2 Zero and Span Checks —
Interim zero and span checks on the
responses of the instrument to known
concentrations must be used to
document withm-control conditions. If
a response is outside of the
prescribed limits, the analyzer is
considered out of control, and the
cause must be determined and
corrected. A quality control chart can
be used to check the analyzer visually
for withm-control conditions
Level 1 and Level 2 span checks
must be conducted in accordance with
the specific guidance given in
Subsection 9.1 of Section 2.0.9. If
permitted by the associated operation
or instruction manual, a CO analyzer
may temporarily operate during the
zero and span checks at reduced vent
or purge flows, or the test atmosphere
may enter the analyzer at a point
other than the normal sample inlet if
the analyzer's response is not likely
to be altered by these deviations from
the normal operational mode. Because
variability information may not be
uncovered by checking only part of
the analyzer's sample-handling
system, however, it is recommended
that these operational deviations be
used only for Level 2 checks
Level 1 zero and span checks must
be conducted every 2 weeks. Level 2
checks should be conducted in
between the Level 1 checks at a
frequency decided on by the user.
Span concentrations for both levels
should be between 70 and 90 percent
of the measurement range. The data
should be recorded on a zero and
span checks form such as that shown
in Figure 3 2.
Level 1 zero and span data are used
for the following:
1. To adjust the analyzer for zero
and span drifts
2 To decide when to calibrate the
analyzer
3. To decide when to invalidate
monitoring data
Items 1 and 2 are detailed in
Subsection 9.1.3 of Section 2.0.9;
Item 3, in Subsection 9 1.4 of the
same section.
When the response from a span
check is outside of the control limits,
the cause for the extreme drift must
be determined and corrective action
taken. Some of the causes for drift are
listed below:
1. Lack of preventive maintenance
2. Fluctuations in electrical power
supply
3. Fluctuations in flow
4. Change in zero-air source
-------
Section 2.6.3
Jan. 1983
Site identification
Site location
Site address
00 (
Technician
1 Inspect thermograph for temperature variations greater than +2°C I4°F); identify time frame of any temperature level out of
tolerance
Comments. Te^D. (jJ///)
2 Inspect sample introduction system for moisture, paniculate buildup, foreign material, breakage, leaks
Comments
of particula^ i* f/-y
3 Is sample line connected to manifold?
Comments
Ofay
4 Inspect data recording system
• Legibility of trace
• Ink supply
• Paper supply
• Chart speed
• Signal range
• Time synchronization
Q^
Corrective
action taken
Comments
5 Inspect analyzer operational parameters
• Sample flow rate
• Oven temp light flashing
• Analyzer in samp/ing mode
• Zero and span potentiometers locked at correct settings
Comments.
6 Zero the analyzer
7 Is unadjusted zero within tolerance?
Comments' ~**t-.\(O—^3
Corrective
action taken
bxy
8 Span the analyzer
9. Is unad/usted span within tolerance?
Comments
10 Enter zero and span values on data form. Figure 3 2
1 1 Return to sampling mode
12 Record pressures of zero and span cylinders
Zero a,r I&O&L Span air
13 Close valve on zero and span cylinders
Signature of technician
Figure 3.1. Example of an operational checklist.
-------
Jan. 1983
Section 2.6 3
.9/fr? irf&ntificfifton ^^ LJ / -^
Location ftoul Y\"{~OuJ V\
Aririr*** H7O Alorrh ^rfy^f
Adiusted zero _s2 _
Pnllfjtant
A
Ana/yrfr /H
/,
J Serial number
Ari/ustGii span
CO
WEi ^IDDE-U IZO
MC.77
Date
Operator
Unadjusted
zero,
% chart
Span
concentration,
ppm
Unad/usted
analyzer
response.
% chart
ppm
Difference,
ppm
5.0
157
Figure 3.2. Example of a Level 1 zero and span check data form
-------
Section 2.6 3
Jan. 1983
5 Change in span gas
concentration
6 Degradation of detector
7. Electronic and physical
components not within
manufacturer's specifications
Corrective actions for the above can
be found in the manufacturer's
instruction/operations manual
3.4.3 Precision Check —
A periodic precision check is used
to assess the data A one-point check
on each analyzer must be carried out
at least once every 2 weeks at a CO
concentration between 8 and 10 ppm
The analyzer must be operated in its
normal sampling mode, and the
precision test gas must pass through
all filters, scrubbers, conditioners, and
other components used during normal
ambient sampling. If permitted by the
associated operation or instruction
manual, a CO analyzer may
temporarily operate during the
precision check at reduced vent or
purge flows, or the test atmosphere
may enter the analyzer at a point
other than the normal sample inlet if
the analyzer's response is not likely to
be altered by these deviations from
the normal operational mode The
standards from which the precision
check test concentrations are obtained
must be traceable to an NBS-SRM or
a commercially available CRM, the
standards used for calibration may be
used for the precision check.
The precision check procedure is as
follows:
1. Connect the analyzer's sample
inlet line to a precision gas
source that has a concentration
between 8 and 10 ppm CO and
that is traceable to an NBS-SRM
or a CRM. If a precision check is
made in conjunction with a
zero/span check, it must be
made prior to any zero and span
adjustments.
2. Allow the analyzer to sample the
precision gas for at least 5 mm
or until a stable recorder trace is
obtained.
3. Record this value on a precision
check data form (Figure 3.3), and
mark the chart as "unadjusted"
precision check.
The biweekly check generates data for
assessing the precision of the
monitoring data; Section 2.0.8 of this
volume of the Handbook presents
procedures for calculating and
reporting precision.
3.4.4 Special Instructions for
Precision Checks on Beckman Model
866 Ambient Carbon Monoxide
Analyzer — Because of the operational
nature of the Beckman Model 866 CO
analyzer, the following slightly
modified procedures for precision
checks and audits of this analyzer
model are generally necessary to
obtain accurate quality assessment of
the ambient readings
The Model 866 uses a dynamic,
flowing reference cell as part of its
compensation for variable
environmental factors such as water
vapor and carbon dioxide (C02J This
mechanism responds rather slowly to
changes in water vapor concentration.
Although the system is entirely
adequate to follow natural
environmental moisture changes, it
does not respond instantly to rapid
changes in moisture level that occur
when the analyzer is switched from
ambient air to dry concentration
standards used for precision checks
and audits. Most concentration
standards obtained from compressed
gas cylinders or diluted from high-
concentration gas cylinders have a very
low moisture level, whereas ambient
air normally contains much higher
levels of water vapor During the
period immediately following a switch
from ambient sampling to a
concentration standard, the analyzer
is operating in a nonequilibrated
mode, which causes a significant
offset (up to 1 to 2 ppm) in the
analyzer's readings Accordingly, the
precision check or audit response will
be inaccurate unless suitable
compensatory measures are taken.
(This effect is accounted for in the
calibration and automatic
standardization procedures in the
operation manual, accurate calibration
and automatic standardization will be
obtained if these procedures are
followed explicitly)
Either of two methods may be used
to avoid errors from this effect during
precision checks and audits The first
is simply to allow sufficient time for
the analyzer to reestablish equilibrium
at the concentration-gas moisture
level. Equilibrium is established when
the analyzer response to this
concentration standard stabilizes at a
new reading somewhat different than
the original reading. (The original
reading may be stable for 10 to 20
minutes after introduction of the dry
gas before the offset occurs.)
Unfortunately, the analyzer may
require as much as 1 to 2 hours to
reach moisture equilibrium at the dry-
gas condition.
The second method takes advantage
of the temporary stable period
immediately after dry gas is
introduced, and it must be completed
before the offset occurs. Prior to the
precision check or audit, dry zero gas
is introduced into the analyzer just
long enough to establish a
temporary, nonequilibrated zero
baseline. The precision or audit
concentration standard(s) is then
introduced, and interpretation of the
reading(s) is based on the net
response referenced to this temporary
zero baseline rather than the
equilibrated zero baseline; i e., the net
difference between the response to
the standard and the temporary
baseline is used with the calibration
curve to determine the response in
concentration units. Finally, dry zero
gas is remtroduced to verify that the
offset has not yet occurred and that
the temporary zero baseline has not
shifted If the temporary zero baseline
has changed significantly, the second
method is not valid and the precision
check or audit must be repeated by
using the first method.
-------
Jan. 1983
Section 2.6.3
Site ID
Location
Address
Pollutant
Analyzer
/4fe 77
/176
Date
Operator
Precision
test gas
concentration,
ppm
Analyzer
response
% chart
ppm
Difference,
ppm
Figure 3.3. Example of precision check form
-------
Section 2.6.3
Jan. 1983
Table 3.1. Daily Activity Matrix
Characteristic
Acceptance limits
Frequency and method
of measurement
Action H
requirements
are not met
Shelter temperature
Sample introduction system
Recorder
Analyzer operational settings
Analyzer operational check
Precision checks
Mean between 22° and
28°C (72° and 82° F); daily
fluctuations not greater
than ±2°C (4°F)
No moisture, foreign
materials, leaks, or ob-
structions, sampling line
connected to manifold
Adequate supply of ink and
chart paper: legible ink
traces, correct setting of
chart speed and range
switches; and correct time
Flow and regulator indica-
tors at proper settings,
analyzer in sampling mode,
and zero and span controls
locked at proper settings
Zero and span within toler-
ance limits fSubsec 913,
Sec. 2.09)
Precision assessed
(Subsec 343)
Edit thermograph chart
daily for variations <2°C
<4°F)
Weekly visual inspection
Weekly visual inspection
Weekly visual inspection
Level 1 zero and span
checks every 2 weeks;
Level 2 checks between
Level 1 checks at frequency
decided by user
Every 2 weeks (Subsec.
3.4.3)
Mark the strip chart for the
affected time period, repair
or adjust the temperature
control system.
Clean, repair, or replace as
needed.
Replenish the ink and chart
paper supplies; adjust the
recorder time to agree with
clock, and note the time on
on the chart
Adjust or repair as needed.
Isolate the source of error,
and then repair; after cor-
rective action, recalibrate
the analyzer
Calculate and report the
precision (Sec. 2.0.8)
-------
Jan. 1983
Section 2.6.4
4.0 Data Reduction, Validation, and Reporting
Quality assurance activities for data
reduction, validation, and reporting
are summarized in Table 4.1 at the
end of this section.
4.1 Data Reduction
Hourly average concentrations from
a strip chart record may be obtained
by the following procedure:
1. Make sure the strip chart record
has a zero trace at the beginning
and end of the sampling period.
2. Fill in the identification data
called for at the top of the hourly
average data form (Figure 4.1)
3. Draw a line from the zero
baseline at the start of the
sampling period to the zero
baseline at the end of the
sampling period by using a
straight edge.
4. Read the zero baseline (% chart)
at the midpoint of each hourly
interval, and record the value on
the data form.
5. Determine the hourly averages
by placing a transparent straight
edge parallel to the horizontal
chart division lines. Adjust the
straight edge between the lowest
and highest points of the trace in
the interval between two vertical
hour lines of interest so that the
area above the straight edge and
bounded by the trace and the
hour lines is approximately equal
to the area below the straight
edge and bounded by the trace
and hour lines, as shown below.
8. Convert reading values (% chart)
to concentrations (ppm) by using
the most recent calibration curve,
and record the CO
concentrations in the last column
of an hourly averages form such
as that shown m Figure 4.1.
An alternative method of converting
% chart to ppm is to eliminate steps 6,
7, and 8 and to use Equation 4-1:
ppm
= Y - Y2
Slope
Equation 4-1
where
Yz = zero baseline from step 4,
% scale
Y = recorder reading from step
5, % scale
Slope = slope of calibration
relationship from Section
2.6.2
4.2 Data Validation
Data of poor quality can be worse
than no data. Data validation to
screen for possible errors or
anomalies is one activity of a quality
assurance program. Statistical
screening procedures should be
applied to identify gross anomalies in
air quality data.6 Subsections 4.2.1
and 4.2.2 recommend two data
validation checks.
4.2.1 Span Drift Check — The first
level of data validation for accepting
or rejecting the monitoring data
should be based on routine periodic
i
5O
40
30
20
JO
0
Straight edge
Area above line
Area below line
1200
1300
1400
1500
Read the deflection (% chart) for all of
the hourly intervals for which data
have not been marked invalid, and
record all values on the hourly
average data form in the column
headed Reading - Original (Orig).
6. Subtract the zero baseline value
from the reading value, and
record the difference.
7. Add the percentage of zero
offset, +5 percent, to each
difference.
checks of the analyzer. Results from
the Level 1 span checks (Section
2.6.3) should be used as the first
Level of data validation. Thus, up to 2
weeks of monitoring data may be
invalidated if the span drift for a
Level 1 span check is >25 percent.
For this reason, it may be desirable to
perform Level 1 checks more often
than the recommended 2-week
frequency
4.2.2 Edit of Strip Chart — The strip
chart should be edited to detect signs
of monitoring system malfunctions
that result in traces that do not
represent "real" data. In a review of a
strip chart, typical points to watch for
are:
1. A straight trace (other than
minimum detectable) for several
hours.
2. A wide solid trace indicating
excessive noise or spikes that are
sharper than is possible with the
normal instrument response time
and are indicative of erratic
behavior. Noisy outputs usually
result when analyzers are
exposed to vibration sources.
3. A long, steady increase or
decrease in deflection.
4. A cyclic trace pattern within a
definite time period, which
indicates a sensitivity to changes
in temperature or parameters
other than CO concentration.
5. A trace that drops below the zero
baseline during certain periods;
this may indicate a larger-than-
normal drop in the ambient room
temperature or the power line
voltage. This may also indicate
CO in the zero-air.
Void any data for any time interval for
which a malfunction of the sampling
system is detected.
4.3 Data Reporting
Information and data from the
hourly average form should be
transcribed to a SAROAD hourly data
form (see Section 2.0.3 of this volume
of the Handbook for details and
instructions for filling out the
SAROAD). If the data are to be placed
in the National Aerometric Data Bank,
further instructions can be obtained
from the SAROAD Users Manual.7
-------
Section 2.6.4
Jan. 1983
City
Site number 2> (f> I L>b OO 1 7
Site location
x-
Checker —
Pollutant
Operator
Calibration curve: Slope fb) -
Intercept (a) =
x = fy-aj/b
Date
(,-(5
(o-lS
Hour
00
01
Reading
Orig
2/
^3
Check
Zero baseline
Orig
L
(,
Check
Difference
Orig
/5
n
Check
y. Add + 5
Orig
20
2Z-
Check
x. pprn
Orig
8
7
Check
Figure 4. J. Sample data form for recording hourly averages
-------
Jan. 1983
Section 2.6.4
Table 4.1. Activity Matrix for Data Reduction
Activity
Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
Data reduction
Span drift check
Editing of strip chart
Data reporting
Stepwise procedure for
data reduction fSubsec.
4.1)
Level 1 span check <25%
(Sec. 2.6.3)
No sign of malfunction
Data transcribed to
SAROAD hourly data form
Follow method Subsec. 4.1
for each strip chart.
Perform Level 1 check at
least every 2 weeks. (Sec
2.6.3)
Visually edit each strip
chart, fSubsec. 4.2)
Visual checks
Review data reduction
procedure.
Invalidate data; take
corrective action; increase
frequency of Level 1
checks until data are
acceptable.
Void data for time interval
for which malfunction of
sampling system detected.
Review data transcription
procedure.
-------
Jan. 1983 1 Section 2.6.5
5.0 Maintenance
The quality assurance activities for
maintenance are described briefly
5.1 Preventive Maintenance
Maintenance requirements vary
from instrument to instrument,
therefore, the supervisor should refer
to the manufacturer's manual for a
thorough discussion of maintenance
requirements for a specific analyzer
After becoming familiar with the
requirements, the supervisor should
develop a suitable preventive
maintenance schedule.
5.2 Corrective Maintenance
Corrective maintenance is any
unscheduled maintenance activity that
becomes necessary because of system
malfunctions; for example,
replacement of a damaged pump
diaphragm, cleaning of a clogged
sampling line, or replacement of a
defective temperature control card
The need for corrective maintenance
becomes apparent as the operator
performs the daily operations
described in Section 2 6 3 of this
Handbook, when the need arises, the
operator should refer to the
manufacturer's manual for
troubleshooting procedures A detailed
maintenance record should be kept on
file to identify recurring system
malfunctions. A sample maintenance
log is presented in Figure 5 1
-------
Section 2.6.5
Jan. 1983
Site identification QC^ (
Location
Pollutant —
£.0
Instrument
/vzv/e.
Serial number
2&B - 7WO
Date
Initials of
technician
Event
initiating
maintenance
maintenance
activity
Comments
Dai l
Figure 5. /. Analyzer maintenance log.
-------
Jan. 1983
Section 2.6.6
6.0 Auditing Procedure
An audit is an independent
assessment of the accuracy of data
generated by an ambient air analyzer
or a network of analyzers.
Independence is achieved by having
the audit performed by an operator
other than the one conducting the
routine field measurements and by
using audit standards, reference
materials, and equipment different
from those routinely used in
monitoring
The audit should be an assessment
of the measurement process under
normal operations--that is, without
any special preparation or adjustment
of the system Routine quality
assurance checks (e.g., those in
Section 263) conducted by the
operator are necessary for obtaining
and reporting good quality data, but
they are not to be considered part of
the auditing procedure.
Three audits are recommended: two
performance audits and a system audit.
The performance audits are described
in detail in Subsection 6.1, and the
system audit is described in
Subsection 6.2 These audit activities
are summarized in Table 6.1 at the
end of this section (See Sections
2.0.11 and 2.0 12 for detailed
procedures for a system audit and a
performance audit, respectively )
Proper implementation of an
auditing program will ensure the
integrity of the data and assess the
accuracy of the data. The technique
for estimating the accuracy of the
data is presented in Section 2.0 8 of
this volume of the Handbook.
6.1 Performance Audits
The following subsections describe
the recommended performance audits:
6.1.1 Calibration Audit —
A calibration audit consists of
challenging the continuous analyzer
with known concentrations of CO
within the measurement range of the
analyzer. Known concentrations of CO
can be generated by using individual
cylinders for each concentration or by
using one cylinder of a high CO
concentration and diluting it to the
desired levels with zero-air. In either
case, the gases used must be
traceable to an NBS-SRM or a
commercially available CRM (Section
2.6.2); acceptable protocol for
demonstrating traceability is
presented in Section 2.0.7. A dynamic
dilution system must be capable of
measuring and controlling flow rates
to within ±2 percent of the required
flow. Flow meters must be calibrated
under the conditions of use against a
reliable standard such as a soap
bubble meter or a wet test meter, all
volumetric flow rates should be
corrected to STP at 25°C (77°F) and
760 mm (29.92 m.) Hg, but if both the
CO and the zero air flow rates are
measured with the same type device
at the same temperature and
pressure, the STP correction factor in
the audit equations can be
disregarded. Note: If a wet test meter
or a bubble meter is used for flow
measurement, the vapor pressure of
water at the temperature of the meter
must be subtracted from the barometric
pressure.
The audit schedule depends on the
purpose for which the monitoring data
are being collected. For SLAMS monitor-
ing, each analyzer must be audited at
least once a year. Each agency should
audit 25 percent of the Reference or
Equivalent analyzers each quarter.8 If
an agency operates fewer than four
analyzers, they should be randomly
selected for reauditing so that one
analyzer is audited each calendar
quarter and each analyzer audited at
least once a year. For PSD monitoring,
each Reference or Equivalent analyzer
must be audited at least once during a
sampling quarter.9
6.1.2 Calibration A udit
Procedures —
The analyzer should be challenged
with at least one audit gas of known
concentration from each of the
following concentrations within the
measurement range of the analyzer
being audited:
Audit point
1
2
3
4
CO concentration range,
ppm
3 to 8
15 to 20
35 to 45
80 to 90
The difference in CO concentration
(ppm) between the audit value and the
measured value is used to calculate
the accuracy (Section 2.0.8) of the
analyzer.
Information on the station,
analyzer, audit device, reference
materials, and aui:.t procedures are of
prime importance because the validity
of the audit results depends on
accurate documentation (Figures 6 1
and 6 2). The following procedure has
been developed to aid m conducting
the audit
1. Record the station's number,
name, and address on the audit
summary report (Figure 6 1)
2 Identify the person(s)
performing the audit and indicate the
date of the audit
3 Record the type of audit device
used. If it was purchased, record the
manufacturer's name, model, and
serial number, if it was assembled by
the user, assign an identification
number so that audits can be
referenced to that particular
apparatus
4 Identify the CO cylmder(s) used
for auditing and the NBS-SRM or
commercially available CRM used to
verify the concentration As required,
the CO cylmder(s) should be
reanalyzed every 6 months (Section
2.0.7)
5. Identify the device used to
measure flow rates, if applicable
6 Connect the audit system outlet
line to the inlet of the CO analyzer.
Analyzers must operate in the normal
sampling mode during the audit, and
the test atmosphere must pass
through all filters, scrubbers,
conditioners, and other components
used during normal ambient sampling
and through as much of the ambient
air inlet system as practicable. The
exception to this rule that is permitted
for certain CO analyzers during
precision and span checks does not
apply for audits.
7. Turn on the zero-air flow, and be
sure that the zero air output exceeds
the analyzer intake by at least 10
percent.
8. Record the analyzer zero value on
the audit summary report
9. Generate the first up-scale audit
point by challenging the analyzer with a
CO concentration within one of the
required concentration ranges; obtain a
stable trace, and record the audit value
and the analyzer response on the audit
summary report
10. Determine the analyzer's
response (ppm) from the analyzer's
latest calibration relationship; if the
relationship is reported as slope and
-------
Section 2.6.6
Jan. 1983
Station
3 Audit performed by
4 Audit device mfr
5 CO standard used
Verified against NBS-SRM
CO
6 Flow measured with
7 Analyzer response to zero-air CO zero =
S Analyzer latest calibration relationship
Equation 6-1
ppm - Y'a
b
Equation 6-2
[CO]A = [CO]STD FCO
fo +FCO
Equation 6-3
% difference =[CO]B-[CO]A WO
[CO]A
2 Analyzer mfr
Model
Model
62..
Concentration
A/I
Date
% sca/e
Y - % scale
b - slope of calibration line
a - intercept of calibration line
F0 - flow rate of dilution air corrected to 25°C and 760 mm Hg.
I/mm
Fco - flow rate of CO standard corrected to 25°C and 760
mm Hg, I/mm
D = CO standard concentration, ppm
- CO audit concentration, ppm
[CO]n = analyzer CO response, ppm
Analyzer
CO
Audit value,
ppm
7.0
zo.o
W.o
Response,
% scale
/?
45
^
Response,
ppm
IEq6-1l
-7.0
2D.O
44.5
% difference
(Eq 6 31
o.o
o.d
/.I
Figure 6.1. Example of an audit summary
-------
Jan. 1983
Section 2.6.6
1 Zero and span checks performed at least biweekly
2 Temperature variations monitored
3 Flow meters routinely calibrated to ±2% accuracy against a reliable standard such as a soap bubble meter or
wet test meter
4 Flow rates monitored routinely
5. Excessive noise minimized
6 Data processing checks performed
7 Multipoint calibration performed routinely, and results of the calibrations recorded
8 Quality control charts maintained for zero and span checks
9 Maintenance performed routinely on pertinent components per manufacturer's manual
10. Calibration gases traceable to an NBS-SRM
J1 Sample introduction system check made weekly
12 Paniculate filter fif used) changed per manufacturer's manual
13 Recording system checked and serviced before each sampling period
14. Recorded data checked for signs of system malfunction
15. Data quality records maintained — completeness, accuracy, precision, and representativeness
16 Calibration gases periodically assayed against an NBS-SRM
Comments
Figure 6.2. Checklist for use by auditor (Measurement of Continuous CO in Ambient Air)
intercept, use Equation 6-1 of Figure
6.1.
11. Repeat steps 9 and 10 for two
more audit points.
12. Calculate the percent difference
for each audit point by using Equations
6-2 and 6-3 of Figure 6.1 and record on
the audit summary report. Results of
the audit are used to estimate the
accuracy of ambient air quality data (as
described in Section 2.0 8).
6.1.3 Data Reduction Audit — Data
reduction involves reading a strip
chart record, calculating an average,
and either transcribing or recording
the results on the SAROAD form. The
audit is an independent check of the
entire data reduction process, and
should be performed by an individual
other than the one who originally
reduced the data. Initially, the data
processing check should be performed
for 1 day out of every 2 weeks of data.
For two 1-hour periods within each
day audited, make independent
readings of the strip chart record and
continue through the actual
transcription of the data on the
SAROAD form. The 2 hours selected
during each day should be those for
which the trace is either most
dynamic (in terms of spikes), or for
which the average concentration is the
highest.
The data processing check is made
by calculating the difference:
d = [CO]n - [CO]A
Equation 6-4
where
d=the difference between the
measured value and the
corresponding check value,
ppm
[CO]R=the recorded analyzer
response, ppm
[CO]* = the audit value of the CO
concentration, ppm
If d exceeds ±2 ppm, all of the
remaining data in the 2-week period
should be checked.
6.2 System Audit
A system audit is an onsite
inspection and review of the quality
assurance activities used for the total
measurement system (sample
collection, sample analysis, data
processing, etc.). System audits are
normally qualitative appraisals of
system quality conducted at the
startup of a new monitoring system
and periodically, as appropriate, to
audit significant changes in system
operation.
An example form for a system audit
is shown in Figure 6.2. The items on
this form should be checked for
applicability to the particular local,
State, or Federal agency.
See Sections 2.0.11 and 2.0.12 for
detailed procedures and forms for a
system audit and a performance audit,
respectively.
-------
Section 2.6.6
Jan. 1983
Table 6-1. Activity Matrix for Audit Procedure
Audit
Acceptance limits
Frequency of method
of measurement
Action if
requirements
are not met
Multipoint calibration audit
Data processing audit
System audit
The difference in concen-
trations between the
measured values and the
audit values is used as a
measure of accuracy.
(Sec. 2.0.8)
Adhere to stepwise
procedure for data reduc-
tion. Sec. 2.6.4, no
difference should exceed
±2 ppm.
Use method described in
this section of the Hand-
book.
Perform at least once per
quarter; see Subsec. 6.1.1
for procedure.
Perform independent data
processing check on a
sample of the recorded
data; e.g.. check 1 day out
of every 2 weeks of data, 2
hours for each day.
Perform at the start-up
of a new monitoring sys-
tem, and periodically as
appropriate; observation
and checklist (Fig. 6.2).
If differences are outside
the agency acceptance
limits, locate the problem
and correct.
Check all remaining data
if one or more data reduc-
tion checks exceed ±2
ppm.
Initiate improved methods
and/or training programs.
-------
Jan. 1983 1 Section 2.6.7
7.0 Assessment of Monitoring Data for Precision and Accuracy
For continuous analyzers, perform a
check every two weeks to assess the
precision of the data. Use these data
to estimate single instrument
precision as described in Section
2.0.8 of this volume of the Handbook.
The precision check procedures
described in Section 2.6.3 are
consistent with those given in
References 8 and 9.
Estimates of single instrument
accuracy for ambient air quality
measurements from continuous
methods are calculated according to
the procedure in Section 2.0.8. The
audit procedure is described in
Section 2.6.6.
-------
Jan. 1983
Section 2.6.8
8.0 Recommended Standards for Establishing Traceability
Two considerations are essential for
ensuring data of the desired quality.
1 The measurement process must
be in statistical control at the
time of the measurement
2 The systematic errors, when
combined with the random
variation in the measurement
process, must result in an
acceptable uncertainty
Evidence of good quality data
includes documentation of the quality
control checks and the independent
audits of the measurement process by
the recording of data on specific forms
or on a quality control chart and by
using materials, instruments and
measurement procedures that can be
traced to appropriate standards of
reference
For traceability to be established,
data must be obtained routinely by
repeat measurements of standard
reference samples (primary,
secondary, and/or working standards).
A condition of process control also
must be established. Working
calibration standards should be
traceable to standards of higher
accuracy
The CO calibration standards must
be traceable to an NBS-SRM (as listed
in Table 8 1) or to a commercially
available CRM.
A list of gas manufacturers who
produce approved CRM is available by
writing to:
U.S. Environmental Protection
Agency
Environmental Monitoring Systems
Laboratory (MD-77)
Research Triangle Park, North
Carolina 27711
ATTN. List of CRM Manufacturers
TableS 1
NBS-SRM's for CO Monitors
SRM
1680
1681
2613
2614
Type
CO in nitrogen
CO in nitrogen
CO in air
CO in air
Vol/unit,
liters
at STP
870
870
870
870
Nominal CO
concentration.
ppm
500
WOO
18.1
43.0
-------
Jan. 1983
Section 2.6.9
9.0 Reference Methods*
Appendix C—Measurement
Principle and Calibration
Procedure for the
Measurement of Carbon
Monoxide in the Atmosphere
(Non-Dispersive Infrared
Photometry)
Measurement Principle
1. Measurements are based on the
absorption of infrared radiation by
carbon monoxide (CO) in a non-
dispersive photometer Infrared
energy from a source is passed
through a cell containing the gas
sample to be analyzed, and the
quantitative absorption of energy by
CO in the sample cell is measured
by a suitable detector. The
photometer is sensitized to CO by
employing CO gas in either the
detector or m a filter cell in the
optical path, thereby limiting the
measured absorption to one or more
of the characteristic wavelengths at
which CO strongly absorbs. Optical
filters or other means may also be
used to limit sensitivity of the
photometer to a narrow band of
interest. Various schemes may be
used to provide a suitable zero
reference for the photometer The
measured absorption is converted to
an electrical output signal, which is
related to the concentration of CO
in the measurement cell.
2. An analyzer based on this
principle will be considered a
reference method only if it has been
designated as a reference method in
accordance with Part 53 of this
chapter.
3. Sampling considerations.
The use of a particle filter on the
sample inlet line of an NDIR CO
analyzer is optional and left to the
discretion of the user or the
manufacturer. Use of filter should
depend on the analyzer's
susceptibility to interference,
malfunction, or damage due to
particles.
Calibration Procedure
1. Principle. Either of two methods
may be used for dynamic
multipoint calibration of CO
analyzers: (1) One method uses a
single certified standard cylinder of
CO, diluted as necessary with zero
air, to obtain the various calibration
concentrations needed. (2) The other
method uses individual certified
standard cylinders of CO for each
concentration needed. Additional
information on calibration may be
found in Section 2.0.9 of Reference
1.
2. Apparatus. The major
components and typical
configurations of the calibration
systems for the two calibration
methods are shown in Figures 1 and
2.
2.1 Flow controller(s). Device
capable of adjusting and regulating
flow rates. Flow rates for the
dilution method (Figure 1) must be
regulated to ±7%.
2.2 Flow meter(s). Calibrated flow
meter capable of measuring and
monitoring flow rates. Flow rates for
the dilution method (Figure 1) must be
measured with an accuracy of ± 2%
of the measured value.
2.3 Pressure regulator(s) for
standard CO cylinder(s). Regulator
must have nonreactive diaphragm and
internal parts and a suitable delivery
pressure.
2.4 Mixing chamber. A chamber
designed to provide thorough mixing
of CO and diluent air for the
dilution method.
2.5 Output manifold. The output
manifold should be of sufficient
diameter to insure an insignificant
pressure drop at the analyzer
connection The system must have a
vent designed to insure atmospheric
pressure at the manifold and to
prevent ambient air from entering the
manifold
3. Reagents.
3.1 CO concentration standard(s).
Cylinder(s) of CO in air containing
appropriate concentration(s) of CO
suitable for the selected operating
range of the analyzer under
calibration; CO standards for the
dilution method may be contained in a
nitrogen matrix if the zero air dilution
ratio is not less than 100:1. The assay
of the cylinder(s) must be traceable
either to a National Bureau of
Standards (NBS) CO in air Standard
Reference Material (SRM) or to an
NBS/EPA-approved commercially
available Certified Reference Material
(CRM). CRM's are described in
Reference 2, and a list of CRM
sources is available from the address
shown for Reference 2. A
recommended protocol for certifying
0
Mixing
Chamber
CO
CO
Std
Output
Manifold
Vent
Extra Outlets Capped
When Not in Use
To Inlet of Analyzer
Under Calibration
*40 CF=R 50 Appendix C (as amended 47 FR
54922, December 6, 1982)
Figure 1. Dilution method for calibration of CO analyzers
-------
Section 2.6.9
Jan. 1983
Flow
Controller
Flowmeter
CO
Std
CO
Std
CO
Std
CO
Std
Zero
Air
Output
Manifold
Vent
K
Extra Outlets Capped
When Not in Use
To Inlet of Analyzer
Under Calibration
Figure 2. Multiple cylinder method for calibration of CO analyzers
CO gas cylinders against either a CO
SRM or a CRM is given in Reference
1 CO gas cylinders should be
recertified on a regular basis as
determined by the local quality control
program
3.2 Dilution gas (zero air) Air, free
of contaminants which will cause a
detectable response on the CO
analyzer The zero air should contain
<0.1 ppm CO A procedure for
generating zero air is given in
Reference 1.
4. Procedure Using Dynamic
Dilution Method.
4.1 Assemble a dynamic calibration
system such as the one shown in
Figure 1 All calibration gases
including zero air must be introduced
into the sample inlet of the analyzer
system. For specific operating
instructions refer to the
manufacturer's manual
4.2 Insure that all flowmeters are
properly calibrated, under the
conditions of use, if appropriate,
against an authoritative standard
such as a soap-bubble meter or wet-
test meter All volumetric flowrates
should be corrected to 25°C and 760
mm Hg (101 kPa) A discussion on
calibration of flowmeters is given in
Reference 1.
4.3 Select the operating range of
the CO analyzer to be calibrated
4.4 Connect the signal output of the
CO analyzer to the input of the strip
chart recorder or other data collection
device All adjustments to the
analyzer should be based on the
appropriate strip chart or data device
readings. References to analyzer
responses in the procedure given
below refer to recorder or data device
responses
4.5 Adjust the calibration system to
deliver zero air to the output manifold
The total air flow must exceed the
total demand of the analyzer(s)
connected to the output manifold to
insure that no ambient air is pulled
into the manifold vent Allow the
analyzer to sample zero air until a
stable response is obtained After the
response has stabilized, adjust the
analyzer zero control Offsetting the
analyzer zero adjustments to + 5
percent of scale is recommended to
facilitate observing negative zero drift
Record the stable zero air response as
Zoo
4.6 Adjust the zero air flow and the
CO flow from the standard CO
cylinder to provide a diluted CO
concentration of approximately 80
percent of the upper range limit (URL)
of the operating range of the analyzer.
The total air flow must exceed the
total demand of the analyzer(s)
connected to the output manifold to
insure that no ambient air is pulled
into the manifold vent The exact CO
concentration is calculated from
[COloui = [COisToxFco
FD + FD
(D
Where.
[CO]o>jT = diluted CO concentration
at the output manifold,
ppm,
[CO]sTo = concentration of the
undiluted CO standard,
ppm,
FCo = flow rate of the CO
standard corrected to 25°C
and 760 mm Hg, (101 kPa),
L/min, and
FD = flow rate of the dilution
air corrected to 25°C and
760 mm Hg, (101 kPa),
L/mm
Sample this CO concentration until a
stable response is obtained. Adjust
the analyzer span control to obtain a
recorder response as indicated below
Recorder response (percent scale) =
[COjouT x 100 + Zco
URL
(2)
Where
URL = nominal upper range limit of
the analyzer's operating range,
and
Zco - analyzer response to zero air,
% scale
If substantial adjustment of the
analyzer span control is required, it
may be necessary to recheck the zero
and span adjustments by repeating
Steps 4 5 and 4.6 Record the CO
concentration and the analyzer's
response
4.7 Generate several additional con-
centrations (at least three evenly spaced
points across the remaining scale are
suggested to verify linearity) by decreas-
ing Fco or increasing FD. Be sure the
total flow exceeds the analyzer's total
flow demand For each concentration
generated, calculate the exact CO
concentration using Equation (1).
Record the concentration and the
analyzer's response for each concentra-
tion Plot the analyzer responses versus
the corresponding CO concentrations
and draw or calculate the calibration
curve
5. Procedure Using Multiple
Cylinder Method.
Use the procedure for the dynamic
dilution method with the following
changes
5.1 Use a multi-cylinder system
such as the typical one shown m
Figure 2.
5.2 The flow meter need not be
accurately calibrated, provided the
flow in the output manifold exceeds
the analyzer's flow demand.
5.3 The various CO calibration
concentration required in Steps 4 6 and
4 7 are obtained without dilution by
selecting the appropriate certified
standard cylinder.
-------
Jan. 1983
Section 2.6.9
^^M
References
1. Quality Assurance Handbook for
ir Pollution Measurement Systems
'olume II—Ambient Air Specific
Methods, EPA-600/4-77-027a, U.S.
Environmental Protection Agency,
Environmental Monitoring Systems
Laboratory, Research Triangle Park,
North Carolina 27711, 1977.
2 A Procedure for Establishing
Traceability of Gas Mixtures to Certain
National Bureau of Standards
Standard Reference Materials. EPA-
600/7-81-010, U S Environmental
Protection Agency, Environmental
Monitoring Systems Laboratory (MD-
77), Research Triangle Park, North
Carolina 27711, January 1981.
-------
Jan. 1983 1 Section 2.6.10
10.0 References
1. 40CFR 50.8.
2. 40 CFR 53.
3. 40 CFR 50, Appendix C (As
amended 47 FR 54922, December 6,
1982)
4. U.S. Department of Commerce.
Catalog of NBS Standard Reference
Materials. NBS Special Publication
260, 1981-1983 Edition National
Bureau of Standards, Washington, D.C.
November 1981.
5. U S. Environmental Protection
Agency. Field Operations Guide for
Automatic Air Monitoring Equipment
Office of Air Programs Publication
Nos. APTD-0736, PB 202-249, and PB
204-650, October 1972.
6 U S. Environmental Protection
Agency. Screening Procedures for
Ambient Air Quality Data. EPA-
450/2-78-037, July 1978
7. U.S Environmental Protection
Agency. Aeros Manual Series Volume
II: Aeros User's Manual. EPA-450/2-
76-029, OAQPS No. 1.2-039,
December 1976.
8. 40 CFR 58, Appendix A.
9. 40 CFR 58, Appendix B.
-------
Jan. 1983
Section 2.6.11
11.0 Data Forms
Blank data forms are provided on
the following pages for the
convenience of the Handbook user.
Each blank form has the customary
descriptive title centered at the top of
the page; however, the section-page
documentation in the top right-hand
corner of each page of other sections
has been replaced with a number in
the lower right-hand corner that will
enable the user to identify and refer
to a similar filled-m form in a text
section. For example, Form CO-1.1
indicates that the form is Figure 1.1 of
the CO method description. Future
revisions of this form, if any, can be
documented as 1.1 A, 1.18, and so
forth. The data forms included are
listed below.
Form
Title
1.1
2 1
2.2
2.3
3.1
3.2
3.3
4.1
5.1
6.1
6.2
Procurement Log
Calibration Summary
CO Calibration and Linearity Checks
Calculation Form for the Method of Least
Squares
Operational Checklist
Level 1 Zero and Span Check Data Form
Precision Check Form
Data Form for Recording Hourly Averages
Analyzer Maintenance Log
Audit Summary
Checklist for Use by Auditor
-------
Section 2.6.11
Jan. 1983
Procurement Log
c
0>
E
o
o
c
o
35
o
Q
U)
O
CJ'
•o
0)
u
0)
cc
0)
ro
Q
"8
o
•c
V
-------
Jan. 1983
Section 2.6.11
1 Station
3 Calibration by
4. Calibrator mfr.
Model
5. CO standard _
Verified against NBS-SRM
By
6 Flow-measuring device
7. Barometric pressure
8. Analyzer's sample flow rate
9 Zero knob setting
Calibration Summary
2 Analyzer
Model
S/N _
Date
S/N
Concentration
Cylinder pressure
Date
Traceability
Shelter temperature
Span knob setting
Calibration Equations
Equation 2- 1
FD or Fco = F (STP correction factor)
Equation 2-2
STP Correction f actor = BP x
760 AT+273
Equation 2-3
[COJOUT =
FD + Fco
Equation 2-4
% scale = [CO]ouT*/00 + zco
URL
F = uncorrected flow rate for dilution air or CO standard gas, l/min
FD = flow rate of dilution air corrected to 25°C and 760 mm Hg, I/mm
Fco = flow rate of CO standard corrected to 25°C and 760 mm Hg.
I/mm
BP - barometric pressure, mm Hg
AT - temperature of gas being measured, °C
[COjouT = concentration at the output manifold, ppm
[CO]sTD= concentration of the undiluted standard, ppm
Zco - recorder response to zero air
Quality Assurance Handbook CO-2.1
-------
Section 2.6.11
Jan. 1983
CO Calibration and Lmear/ty Checks
Calibration
points
\ I " | I -
/ ; 2 ' 3 4
Fco. ' Fa [COJouT,
I/mm I/ mm ppm % scale
IEQ 2- 1 & 2-21* (Ed 2- 1 & 2-21 (Eq 2-31 (Eq 2-41
Zero
80% URL
1
2
3
< \ \
"Equations 2-1 through 2-4 are given in Figure 2 1 and in the text
Calibration Relationship
c
o
I
C
•q:
100
90
80
70
60
50
40
30
20
10
10
20
30
40
50
fCOJour, ppm
Slope (b) of calibration relationship
Intercept (a) of calibration relationship
Quality Assurance Handbook CO-2.2
-------
Jan.1983
Section 2.6.11
Calculation Form for the Method of Least Squares
Calibration
point
Zero
80% URL
1
2
3
Concentration,
ppm
X
X2
Recorder
reading,
% scale
Y
Y2
*Y
. X = Ix//7 = .
y = "Ly/n = .
. and
n = number of calibration points.
The equation of the line fitted to the data is written as:
Y=y + b(x-x) - (y-bx) + bx = a + bx
where Y = predicted mean response for corresponding x
b - slope of the fitted line
a - intercept where the line crosses the y-axis
JKY . fr) fly)
b= 0. = = .
a = y - bx = .
Quality Assurance Handbook CO-2.3
-------
Section 2.6.11
Jan. 1983
Site identification
Site location
Operational Checklist
Date
Technician
Site address
1. Inspect thermograph for temperature variations greater than ±2°C (4°F); identify time frame of any temperature level out of
tolerance
Comments:
2 Inspect sample introduction system for moisture, paniculate buildup, foreign material, breakage, leaks
Comments:
3. Is sample line connected to manifold!'
Comments:
4. Inspect data recording system
Legibility of trace
Ink supply
Paper supply
Chan speed
Signal range
Time synchronization
OK
Corrective
action taken
Comments:
5. Inspect analyzer operational parameters
• Sample flow rate
• Oven temp light flashing
• Analyzer in sampling mode
• Zero and span potentiometers locked at correct settings
OK
Corrective
action taken
Comments:
6 Zero the analyzer
7. Is unadjusted zero within tolerance?
Comments:
8. Span the analyzer
9. Is unadjusted span within tolerance?
Comments:
10. Enter zero and span values on data form. Figure 3.2
11. Return to sampling mode
12. Record pressures of zero and span cylinders
Zero air Span air
13. Close valve on zero and span cylinders
Signature of technician
Quality Assurance Handbook CO-3.1
-------
Jan. 1983 7 Section 2.6.11
Level 1 Zero and Span Check Data Form
Site idenfifiratinn
1 c.rflf/fin
Address
Adnisted zero
, Pfi//i//anf
AnalyjKr
Serial n^rrfhor
Adjusted span
Date
Operator
Unadjusted
zero,
% chart
Span
concentration,
ppm
Unadjusted
analyzer
response.
% chart
ppm
Difference,
ppm
Quality Assurance Handbook CO-3.2
-------
Section 2.6.11
Jan. 1983
Site ID
Location
Address
Precision Check Form
Pollutant
Analyzer
Serial number
Date
Operator
Precision
test gas
concentration,
ppm
Analyzer
response
i chart
ppm
Difference,
ppm
Quality Assurance Handbook CO-3.3
-------
City
Site location
Checker
Jan. 1983 9 Section 2.6.11
Data Form lor Recording Hourly Averages
Site number
Pollutant
Operator
Calibration curve: Slope fb) =
Intercept (a) =
x = (y-a)/b
Date
Hour
Reading
Orig
Check
Zero baseline
Orig
Check
Difference
Orig
Check
y. Add + 5
Orig
Check
x, ppm
Orig
Check
Quality Assurance Handbook CO-4 1
-------
Section 2.6.11
10
Jan. 1983
Analyzer Maintenance Log
Site identification
Location
Address
Pollutant
Instrument
Serial number
Date
Initials of
technician
Event
initiating
maintenance
maintenance
activity
Comments
Quality Assurance Handbook CO-5.1
-------
Jan. 1983
7. Station
3 Audit performed by
4. Audit device mfr. _
S/N
5. CO standard used
Verified against NBS-SRM
By
6. Flow measured with
7. Analyzer response to zero-air: CO zero =
8. Analyzer latest calibration relationship
Equation 6-1
ppm
= Y-a
Equation 6-2
[CO]A = ICOlsTD f co
FO +FCO
Equation 6-3
% difference = [CO]R-[CO]A )00
[COJ*
11
Audit Summary
Section 2.6.11
2. Analyzer mfr. .
Model
S/N _
Date
Model
Concentration
Date
% scale
Y = % scale
b - slope of calibration line
a = intercept of calibration line
Fo - flow rate of dilution air corrected to 25°C and 760 mm Hg,
I/mm
Fco = flow rate of CO standard corrected to 25°C and 760
mm Hg, I/mm
[CO]siD = CO standard concentration, ppm
[COU = CO audit concentration, ppm
[CO]n - analyzer CO response, ppm
Analyzer
CO
Audit value,
ppm
Response,
% scale
Response,
ppm
(Eq6-1)
% difference
(Eq 6-3)
Quality Assurance Handbook CO-6.1
-------
Section 2.6.11 12 Jan. 1983
Checklist for Use by Auditor
Yes No
/. Zero and span checks performed at least biweekly
2. Temperature variations monitored
3 Flow meters routinely calibrated to ±2% accuracy against a reliable standard such as a soap bubble meter or
wet test meter
4. Flow rates monitored routinely
5. Excessive noise minimized
6 Data processing checks performed
7. Multipoint calibration performed routinely, and results of the calibrations recorded
8 Quality control charts maintained for zero and span checks
9 Maintenance performed routinely on pertinent components per manufacturer's manual
10 Calibration gases traceable to an NBS-SFtM
11 Sample introduction system check made weekly
12. Paniculate filter (if usedl changed per manufacturer's manual
13 Recording system checked and serviced before each sampling period
14. Recorded data checked for signs of system malfunction
15. Data quality records maintained—completeness, accuracy, precision, and representativeness
16. Calibration gases periodically assayed against an NBS-SRM
Comments:
Quality Assurance Handbook CO-6.2
-------
. 1982
Section 2.9.0
V-/EPA
United States
Environmental Protection
Agency
Environmental Monitoring Systems
Laboratory
Research Triangle Park NC 27711
Research and Development
EPA-600/4-77-027a
Test Method
Section 2.9
Equivalent Method for the
Determination of Sulfur
Dioxide in the Atmosphere
(Fluorescence)
Outline
Section
Summary
Method Highlights
Method Description
1. Procurement of Apparatus
and Supplies
2. Calibration of Equipment
3. Operation and Procedure
4. Data Reduction, Validation, and
Reporting
5. Maintenance
6. Audit Procedure
7. Assessment of Monitoring Data
for Precision and Accuracy
8. Recommended Standards for
Establishing Traceability
9. Equivalent Method
10. References
11. Data Forms
Documentation
2.9.0
29.0
2.9.1
2.9.2
2.9.3
2.9.4
2.9.5
2.9.6
2.9.7
2.9.8
2.9.9
2.9.10
2.9.11
Number
of Pages
1
1
5
10
7
1
2
1
1
1
1
4
Summary
The Reference Method for the
determination of sulfur dioxide in the
atmosphere (i.e., pararosaniline
method) is discussed in Section 2.1 of
this Handbook. Many organizations,
however, will find it advantageous to
conduct continuous monitoring of S02
in ambient air by employing automated
monitoring techniques. For use in air
quality surveillance systems, state and
local agencies are required1 to use
analyzers that are EPA designated
reference or equivalent methods.
A current list of all designated
reference and equivalent methods is
maintained by EPA and updated
whenever a new method is
designated. This list may be obtained
from any EPA Regional Office or from
the Environmental Monitoring
Systems Laboratory, Department E,
MD-77, Research Triangle Park, North
Carolina 27711. Moreover, any
analyzer offered for sale as a reference
or equivalent method after April 16,
1976, must bear a label or sticker
indicating that the analyzer has been
-------
Section 2.9.0
Sept. 1982
designated as a reference or
equivalent method by EPA. Further
discussion of the concepts of reference
and equivalent methods appears in
Section 2.0.4 of this Handbook.
Quality assurance procedures for
measuring SOi with a fluorescence
automated sampler are not instrument
specific, therefore the quality
assurance functions described below
are applicable to all fluorescent
analyzers designated as EPA
equivalent methods
Method Highlights
In this quality assurance document
for the fluorescent SO2 Equivalent
Methods, the procedures are designed
to serve as guidelines for the
development of agency quality
assurance programs. Because
recordkeeping is a critical part of
quality assurance activities, several
data forms are included to aid in the
documentation of necessary data. The
blank data forms (Section 2.9.11) may
be used as they are, or they may be
used as guidelines for preparing forms
more appropriate to the individual
agency; partially filled-m forms are
interspersed throughout the text of the
method description to illustrate their
uses. Activity matrices at the end of
pertinent sections can be used for
quick review of the material covered in
the text sections. Where appropriate,
reference is made to corresponding
sections in Section 2.5 of this
Handbook in order to minimize the
repetition of discussion in this section.
This is applicable primarily to Sections
2.9.4, 2.9.6, and 2.9.11, where the
corresponding sections of Section 2.5
(i.e., 2.5.4, 2.5.6, and 2.5.11) can be
substituted for these sections. The
only exceptions are changes in two
figures of Section 2.9.11. Following is
a brief summary of the material
covered in this SOz method
description.
1. Procurement of Equipment
Section 2.9.1 gives the
specifications, criteria, and design
features of the equipment and material
required for the operation and quality
assurance of a continuous fluorescent
SOz analyzer. The selection of the
correct equipment and supplies is a
prerequisite to a quality assurance
program. This section is designed to
provide a guide for the procurement
and initial check of equipment and
supplies.
2. Calibration of Equipment
Section 2.9.2 provides procedures
and forms to be used in selecting and
checking calibration equipment,
performing a multi-point calibration,
and evaluating calibration data
Subsections 2.1 and 2 2 deal primarily
with minimum acceptable
requirements for equipment and
standards to be used m the generation
of S02 concentrations. Subsection 2.4
provides a step-by-step description of
the recommended calibration
procedure for a fluorescent 862
analyzer along with example
calculations. The data forms (Figures
2 1 and 2.2 of Section 2.9.2) are to be
used in documentation of calibration
data The primary element of quality
control is dynamic instrument
calibration.
3. Operation and Procedure
Section 2.9.3 outlines protocol to be
followed by the operator during each
site visit. Checks should include visual
inspection of the shelter, sample
introduction system, analyzer and
recorder In addition, analyzer
performance checks consisting of zero,
span, and precision points are to be
made. To provide for documentation
and accountability of activities, a
checklist similar to the example
provided in Figure 3.1 of Section 2.9.3
should be compiled and then filled out
by the field operator as each activity is
completed. Analyzer Level 1 zero and
span checks must be carried out at
least once every two weeks. Level 2
zero and span checks should be
conducted between the Level 1 checks
at a frequency desired by the user. The
user may desire to perform additional
Level 1 zero and span checks and
perform no level 2 checks. Span
concentrations for either a Level 1 or
Level 2 check should be between 70
and 90% of the measurement range. In
addition, a one point precision check is
to be done at least every two weeks at
an SO2 concentration between 0.08
and 0.10 ppm. These data are
compiled and used to report precisions
of a SLAMS or a NAMS network. Data
forms similar to Figures 3.2 and 3.3 of
Section 2.9.3 are to be used in
documenting the analyzer
performance checks. An essential part
of the quality assurance program is a
scheduled series of checks for the
purpose of verifying the operational
status of the monitoring system.
4. Data Reduction
Section 2.9.4 is identical to Section
2.5.4 and only the summary of quality
assurance activities is provided.
5. Maintenance
Section 2.9.5 addresses
recordkeeping and scheduled activities
pertinent to preventive and corrective
maintenance. An analyzer
maintenance log is presented in Figure
5.1 of Section 2.9.5. Preventive and
corrective maintenance are necessary
to minimize loss of air quality data due*
to analyzer malfunctions and out of
control conditions.
6. A ssessment of Data for A ccuracy
and Precision
Section 2.9.6 is identical to Section
2.5.6. Section 2 9.7 describes the
techniques for assessment of data for
accuracy and precision.
7. Reference Information
Section 2.9.8 discusses the
traceability of working standards to
established standards of higher
accuracy, a necessary prerequisite for
obtaining accurate data.
Section 2.9.9 contains a brief
description of an equivalent method
and references further information m
Section 2.0.4, and Section 2.9.10
contains pertinent references.
Section 2.9.11 contains blank data
forms for the convenience of the user.
Only two data forms are provided in
this section; all other data forms are
identical to the corresponding form in
Section 2.5.11 The identification in
the lower right hand corner should be
changed from FPD-X- (Section 2.5.11)
to FLR-X for field use.
-------
Sept. 1982
Section 2.9.1
1.0 Procurement of Apparatus and Supplies
Continuous sulfur dioxide
monitoring activities using fluorescent
analyzers require the procurement of
basic sampling equipment and
peripheral supplies. These include, but
are not limited to the following:
1 Equivalent method fluorescent
SOz analyzer (see Subsection
1.1 for an address for obtaining
an up-to-date list of analyzers)
2. Strip chart recorder or data
logging system
3. Sampling lines
4. Sampling manifold
5. Calibration equipment
6. NBS-SRM or commercial CRM
calibration standard
7. Working gas traceable to NBS or
CRM standard
8. Zero-air source
9. Spare parts and expendable
supplies
10. Record forms
11. Independent audit system.
It is recommended that the person
responsible for purchasing materials
maintain a log book to record the
vendor name; the part number and
price; the dates ordered and received;
and other pertinent information. An
example of a log is Figure 1.1 The log
will serve as a reference for future
procurement needs and as a budgeting
tool for planning future monitoring
programs. Quality assurance activities
for procurement of apparatus and
supplies are summarized in Table 1.1
at the end of this section.
1.1 SO2 Analyzer
As stated in the Code of Federal
Regulations,1 each method for
measuring SO2 shall be either a
reference or equivalent method when
such monitoring is undertaken for
determining compliance with the
National Ambient Air Quality
Standards (NAAQS's).
Currently those analyzers
designated as equivalent methods use
one of the following four detection
principles: flame photometric,
coulometric, fluorescence, or second-
derivative spectrometry. Because an
analyzer uses one of these
measurement principles does not
make it an equivalent method. It must
be so designated by EPA. Information
help in a decision of which analyzer to
purchase may be found in Reference
2. Only the fluorescent method is
discussed in this section.
Options that are available range
from automatic zero and span
functions to complete telemetry
systems, whereby daily zero and span
checks and real-time data are
transmitted from the site to a central
location. Although these options have
advantages, their absence from the
basic monitor will not detract from
performance. The necessity and
desirability of options is dictated by the
availability of field personnel, the
accessibility of the site, and the
limitations of the budget.
The buyer should purchase only
analyzers designated by EPA as an
equivalent method, and should request
that the manufacturer supply
documented evidence that the
analyzer performs within
specifications (Table 4.1, Section 2.0 4
of this Handbook). The best evidence is
a strip chart record showing the
specific analyzer's zero drift, span drift,
electronic noise, rise time, fall time,
and lag time. The strip chart also
serves as a reference for determining
whether the performance of the
analyzer deteriorated over time with
use. In addition, the user should
reverify these performance
characteristics during the initial
calibration by using abbreviated forms
of the test procedures provided in 40
CFR53.1
Acceptance of the analyzer should
be based on results of these
performance tests. Once accepted, the
reference and equivalent analyzers are
warranted for one year by the
manufacturers to operate within the
performance specifications
An up-to-date list of analyzers
designated as reference or equivalent
methods for SOz is available by writing
to:
U.S. Environmental Protection Agency
Environmental Monitoring Systems
Laboratory
Department E, MD-77
Research Triangle Park, North Carolina
27711
1.1.1 Principle of Fluorescent
Detection - This principle is based on
detection of the characteristic
fluorescence released by the sulfur
dioxide molecule when it is irradiated
by ultraviolet light This fluorescent
light is also in the ultraviolet region of
the spectrum, but at a different
wavelength than the incident
radiation. The fluorescent wavelengths
usually monitored are between 190
and 230 nm. In this region of the
spectrum, there is relatively little
quenching of the fluorescence by other
molecules occurring in ambient air. As
in flame photometry, the light is
detected by a photo multiplier tube
(PMT) that, through the use of
electronics, produces a voltage
proportional to the light intensity and
SOz concentration
The fluorescent light reaching the
PMT is usually modulated to facilitate
the high degree of amplification
necessary. Some analyzers
mechanically "chop" the incident
irradiation before it enters the reaction
chamber This process is accomplished
by a fan-blade-like chopper rotating at
a constant speed, which alternately
blocks and passes the light to the
chamber. Other instruments
electronically pulse the incident light
source at a constant rate.
Potential interferences to the
fluorescent technique include any
species that either quenches or
exhibits fluorescence. Both water
vapor and oxygen strongly quench the
fluorescence of SOa at some
wavelengths. Where water vapor
presents a problem, it can be removed
by a dryer within the instrument. In
most analyzers, the water interference
is minimized by careful selection of the
incident radiation wavelength.
Difference in oxygen concentrations
between the two matrices can become
significant if a low-level SO2-in-
nitrogen cylinder gas is diluted to
prepare a calibration standard. In such
a case, the nitrogen in the pollutant
flow stream may "dilute" the oxygen
m the dilution air stream, significantly
decreasing oxygen concentration. This
situation can be avoided by keeping
the concentration of SOz in the
cylinder gas high enough that the
nitrogen contributed by the pollutant
flow stream is insignificant with
respect to the total flow volume.
Aromatic hydrocarbons such as
naphthalene exhibit strong
fluorescence in the same spectral
regions as SOz and are major
mterferents These aromatics must be
-------
Section 2.9.1
Sept. 1982
removed from the sample gas stream
by an appropriate scrubber upstream
of the reaction chamber. The
scrubbers may operate at ambient or
elevated temperature. Certain
elevated-temperature scrubbers,
however, have the potential for
converting ambient hydrogen sulfide
' (which normally does not interfere
with the fluorescent technique) into
SOz. In these cases, the hydrocarbon
scrubber must be preceded by a
scrubber for H2S
1.1.2 Specific Fluorescent
Analyzers - Currently, four (4)
instrument manufacturers have EPA
designated equivalent fluorescent SO?
analyzers The manufacturers and
their respective designated equivalent
methods are: Thermo Electron
Corporation (TECO), EQSA-0276-009,3
Beckman, EQSA-0678-029;4 Monitor
Labs, Inc., EQSA-0779-039;5 and
Meloy (Columbia Scientific Industries
Corp.) EQSA-0580-046 6
The TECO Series 43 fluorescent SO2
monitor utilizes a pulsed UV light to
excite the SO2 molecules. TECO states
six (6) major reasons for using a
pulsed UV lamp-3
1. Long bulb life
2. High intensity—improved signal to
noise ratio
3. Small bulb size
4 Low power requirements—less
than 1 watt
5. Long-term stability
6. Chopped signal processing—no
dark current drift
Before passing into the reaction
chamber the sample air passes
through a permeation dryer, to remove
water vapor, and an aromatic
hydrocarbon cutter (replace every 18
months of operation). The instrument
operates with a sample flow rate
between 472 and 1888 cmVmin.
The Beckman Model 953 fluorescent
SOz monitor uses a continuous UV
light source (deuterium lamp) but
mechanically chops the light signal
before it enters the reaction chamber.
The sample air passes through a
selective scrubber, for the removal of
H2S and mercaptans (change every 12
months), and a heated temperature
controlled reactor which removes
polynuclear aromatic compounds
(replace every 6 months). The sample
then passes into a heated,
temperature-controlled fluorescence
reaction chamber. The chamber is
heated to reduce condensation of
water vapor. The instrument operates
with a sample flow rate of 400 to 700
cmVmin.
The Monitor Labs Model 8850 uses
UV light from an arc tube to excite the
SOz molecules. The UV light passes
through a mechanical chopper before
entering the reaction chamber Sample
air passes through a five (5)-micron
teflon paniculate filter and a catalyst
(replaced every 1 2 months) for removal
of aromatic hydrocarbons before
entering the heated (40°C) reaction
cell The instrument operates with a
sample flow rate of 500 ± 50
cmVmin.
The Meloy Model SA700 fluorescent
S02 analyzer operates with a
continuous wave of UV light from a
deuterium lamp The instrument uses
a UV detector to monitor lamp
intensity in the reactor cell and
compensates and adjusts the UV
source as the source ages and as
contamination accumulates on optical
surfaces. The instrument uses no
optical or mechanical chopper.
The sample air passes through a
membrane dryer to remove water
vapor and a hydrocarbon scrubber
must be replaced as part of scheduled
annual maintenance The instrument
operates with a sample flow rate of
200 to 500cm3/mm.
1.2 Strip Chart Recorder
Strip chart recorders are
commercially available with a wide
variety of prices and specifications.
Factors to be considered when
purchasing a recorder are:
1 Compatibility with the output
signal of the analyzer
2 Chart width (minimum of 1 5 cm is
recommended for desired
accuracy of data reduction)
3. Chart speed (>2.5 cm/h)
4. Response time
5. Precision and reliability
6. Flexibility of operating variables
(speed and range)
7. Maintenance requirements.
1.3 Sampling Lines and
Manifolds
Sampling lines and manifolds should
be Teflon or glass to minimize reaction
with and degradation of the S02. The
residence time within the sampling
lines should be minimized to reduce
the possibility of interaction of the SOa
sample with interim surfaces. If
paniculate filters are employed, they
should be of Teflon construction
1.4 Calibration Equipment
The recommended calibration
procedure requires both a permeation
tube that is traceable to NBS standards
in a temperature-controlled
environment and a diluent airstream
free of S02 (<0.001 ppm). A detailed
discussion of this calibration
procedure appears in Section 292.
Calibration may also be conducted by
diluting an SO2 standard gas with zero
air
The calibration system (purchased or
built) must meet the guidelines
outlined in the Federal Register.1
Calibration systems of the types
described are commercially available.
Several manufacturers of continuous
S02 analyzers either offer compatible
calibration systems or can inform the
user on where to purchase such
systems When purchasing a
calibration system, the following
factors should be considered.
1. The permeation tube must be
traceable to NBS standard
reference materials (NBS-SRM).
2 The method for measuring air flow
through the calibrator must be
accurate within ±2% of the actual
flow
3. The temperature control module
must be capable of maintaining
the permeation tube at a
predetermined temperature within
±0 1 °C (0.2°F). The ability to make
an independent check of the
temperature within the
permeation tube chamber is
desirable.
4. The calibrator must be portable if
it is to be used at more than one
site.
5. Maintenance requirements should
be minimal.
Permeation tubes are commercially
available or may be prepared in the
laboratory.2'7 The working permeation
tube must be traceable to an NBS-
SRM. If the permeation tube supplied
with the calibrator is not certified, or if
the user prepares his own tubes, the
user must conduct certification tests
and thus purchase an NBS-SRM. The
following permeation tubes are
available as NBS-SRM's:8
SRM
1625
1626
1627
S02
SO2
S02
Type »
permeation
permeation
permeation
tube
tube
tube
Tube
length,
cm
10
5
2
Nominal
permeation
rate.
/yg/min at 25°
2.8
1.4
0.56
C
-------
Sept. 1982
Section 2.9.1
An acceptable protocol for
demonstrating the traceability of
commercial permeation tubes to NBS-
SRM's is described in Section 2.0.7 of
this volume of the Handbook.
The user will need a source of zero
air that is free of contaminants that
would cause any detectable response
with the SOa analyzer. Zero-air is
commercially available in cylinders or
can be generated by the user. Because
fluorescent SO2 analyzers may be
sensitive to the composition of
synthetically prepared zero-air, a clean
air system utilizing ambient air may be
more desirable to use for zero and
dilution purposes. If ambient air is not
used, the zero-air cylinder must
contain the major constituent gases
normally found in ambient air,
especially oxygen which is known to
quench the fluorescence response.
1.5 Spare Parts and
Expendable Supplies
In addition to the basic equipment
discussed above, it is necessary to
maintain an inventory of spare parts
and expendable supplies. The
manufacturer's manual specifies
which parts require periodic
replacement and the frequency of
replacement. Based on these
specifications, the management of the
monitoring network can determine
which parts and how many of each
should be available at all times. A
generalized list of spare parts and
expendable supplies is provided below
(for specific requirements, refer to the
manufacturer's manual):
1. Particulate filters
2. Selective scrubbers for the
removal of aromatic
hydrocarbons
3. Sampling lines
4. Pump diaphragms
5. Drier columns
6. Activated charcoal
7. Recorder chart paper and ink or
pens
8. Calibration gas
9. Record forms
10. Spare fittings.
schedules in Section 2.1.2 of this
Handbook
1.7 Record Forms
Recordkeeping is critical for all
quality assurance programs. Standard
forms similar to those in this
Handbook should be developed for
individual programs. Three questions
to consider in the development and
storage of record forms are:
1. Does the form serve a necessary
function?
2. Is the documentation complete?
3. Will the forms be filed so that they
can be retrieved easily when
needed?
1.8 Audit System
An independent audit system is a
necessary part of the quality
assurance program Two types of audit
systems may be used:
1. A system using an NBS traceable
permeation tube (Subsection 1.4),
or
2. A dynamic dilution system with a
tank of SOz certified traceable to
an NBS-SRM or a commercially
available Certified Reference
Material (CRM) and a zero-air
supply (Section 2.5.6).
In either case, the system used for
auditing must not be the same as that
used to calibrate the analyzer.
1.6 Reanalysis of Calibration
Working Standards
All working standards for
calibrations should be reanalyzed at
least once every 6 mo. (Subsection
7.2.6 of Section 2.0.7 describes the
procedures for analysis and for
reanalysis of permeation devices).
Flow-measuring devices should be
recalibrated using the procedures and
-------
Section 2.9.1
Sept. 1982
a
c
-------
Sept. 1982
Section 2.9.1
Table 1.1. Activity Matrix for Procurement of Equipment and Supplies
Equipment and
supplies
Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
Fluorescence
S02 analyzer
Strip chart
recorder
Sampling lines
and manifolds
Calibration
devices
SOz permeation
tube
Zero -air
Record forms
Audit system
Performance according
to specifications in
Table 4.1, Sec 2.0.4
Compatible with output
signal of analyzer;
chart width of 15 cm
(6 in.) is recommended;
accurate chart speed
Constructed of Teflon
or glass
Must meet guidelines
of Reference 1
Traceable to NBS-SRM;
meets limits in trace-
ability protocol for
accuracy and stability
(Sec 2.0.7)
Clean dry ambient air.
free of contaminants
that cause detectable
responses with the SOi
analyzer
Standard form
developed
Must not be the same
system as used for
calibration, either an
NBS traceable perme-
ation tube or a dynamic
dilution system (Sub-
sec 1.8)
Have the manufacturer
provide a strip chart
recording of specific
analyzer's performance;
verify performance
specifications at
installation
Check upon receipt
As above
See Reference 1
Analyze against an
NBS-SRM; protocol
in Sec 2.0.7
See Sec 2.9.2
N/A
Check the system
against a known
standard
Have the
manufacturer
make proper
adjustments;
recheck the
performance
Return to
supplier
As above
As above
Obtain new
working stan-
dard, check
for traceabihty
Obtain air
from another
source or re-
generate
Revise forms
as appropriate
Locate problem;
correct, or
return to
supplier
-------
Sept. 1982
Section 2.9.2
2.0 Calibration of Equipment
The accuracy and precision of data
derived from the air monitoring
equipment are dependent on the
quality assurance procedures used,
primarily the dynamic instrument
calibration. Calibration determines the
relationship between the observed and
the true values of the variable being
measured. Table 2.2 at the end of this
section summarizes the quality
assurance activities for calibration.
Dynamic calibration involves
introducing gas samples of known
concentrations into an instrument in
order to adjust the instrument to a
predetermined sensitivity and to derive
a calibration relationship. This
relationship is derived from the
instrument's responses to successive
samples of different known
concentrations. Introducing these
standard gas mixtures in decreasing
order of concentration will minimize
the response times. As a minimum,
three reference points and one zero
:Oint are recommended to define this
slationship. Linearity of fluorescent
_nalyzers is also checked at this time.
The true value of the calibration gas
must be traceable to NBS-SRM's
(Section 2.0.7).
Most currently available monitoring
instrument systems (e.g., the
fluorescent S02 analyzer) are subject
to drift and variation in internal
parameters, and thus cannot be
expected to maintain accurate
calibration over long periods of time.
Therefore, it is necessary to
dynamically check the calibration
relationship on a predetermined
schedule. Precision is determined by a
one-point check at least once every 2
weeks. Accuracy is determined by a
three-point audit once each quarter.
Zero and span checks (Subsection
3.4.2) must be used to document
withm-control conditions; these
checks are also used in data reduction
and validation.
2.1 Calibration Gases
The recommended method of
dynamically calibrating a fluorescent
SC>2 analyzer requires both a certified
permeation tube traceable to an NB§-
kSRM in a temperature-controlled x
nvironment (±0.1 °C) and diluent air
void of SOz «0.001 ppm). To conduct
biweekly precision checks and Level 1
zero and span checks, the user will
need a supply of zero air, a cylinder of
SOz (50 to 100 ppm) in nitrogen, and a
dynamic dilution system or a
calibration system with a permeation
tube capable of generating the
precision check point at 0.08 to 0.1
ppm and a span check point at 70 to
90 percent of the analyzer's
measurement range. To implement a
quality assurance program for
calibration, the user will therefore
need the following:
1. An SOz permeation tube or device
that is traceable to an NBS-SRM
2. Zero air
3. An SC>2 span gas that is traceable
to an NBS-SRM or commercially
available CRM
4. A calibration system.
2.1.1 SOz Permeation Tubes - The
NBS-SRM's provide a reference
against which all calibration gas
mixtures must be compared. See
Section 2.9.1 (Subsection 1.4) for an
address for obtaining a list of NBS-
SRM's which are available for SOz
analyzers.
One function of NBS is to supply
standards, but they do not supply
working calibration gases. Therefore
the user is advised either to purchase
commercially available certified
permeation tubes that are traceable to
NBS standards or to make the tubes.2
In either case, the user is responsible
for the verification and reanalysis of
working standards versus NBS-SRM's
or CRM's. Procedures the user must
follow to verify working calibration
gases are outlined in Section 2.0.7.
2.1.2 Dilution Air - Zero-air, free of
contaminants which could cause a
detectable response in the fluorescent
SOz analyzer, must be used for the
calibration, the precision check, and
the Level 1 zero and span checks. This
air is used to establish the analyzer
zero base line and to dilute the SOz to
the required concentrations. Zero-air
may be supplied from cylinders or from
a clean air system.
Because the fluorescent reaction
has some degree of sensitivity to
aromatic hydrocarbons, COz levels,
and to the oxygen/nitrogen ratio,3 it is
recommended that a clean air system
be used. The air for this system must
be drawn from outside the station to
prevent excess COz levels. Water
vapor and aromatic hydrocarbons
should be removed from the zero air.
If compressed air cylinders are used,
the air should have the following
properties for use with fluorescent
analyzers:
1. The same Oz and Nz percentage
composition as ambient air
(20.94% Oz, 78 08% N2).
2. A COz content similar to that of
ambient air (between 300 and 400
ppm).
3. Less than 0.1 ppm aromatic
hydrocarbons.
2.1.3. SOzPrecision and Span
Gases - Aluminum or steel cylinders
containing 50 to 100 ppm SOz in N2
are available from most specialty gas
suppliers. Aluminum cylinders have
been demonstrated by NBS to have
superior stability for storing SOz
mixtures, and they are preferred
whenever possible. These gases can '
be diluted to the desired concentration
by using zero-air and a dynamic
dilution system The cylinder gas
concentration should be certified to
NBS-SRM or commercially available
CRM (Certified Reference Materials)
using EPA Traceability Protocol No. 2
(Section 2.0.7). NBS-SRM or
commercially available CRM at 50 and
100 ppm SOz in N2 should be used for
the traceabihty analysis. A CRM may
be used directly for precision or span
checks. However, due to the limited
supply of NBS-SRM, an SRM should
not be used directly for routine
precision or span checks. A list of gas
manufacturers who have approved
CRM's is available by writing to:
U.S. Environmental Protection
Agency
Environmental Monitoring Systems
Laboratory (MD-77)
Research Triangle Park, North
Carolina 27711
ATTN: List of CRM Manufacturers
(Note: CRM's are cylinder gases
prepared by gas manufacturers
according to an NBS-EPA procedure to
within ±1 % of existing SRM
concentrations. Each CRM lot of 10 to
50 cylinders is audited by EPA. Each
lot receives written approval from NBS
and this approval must accompany any
CRM sold.)
Precision and span gases may also
be generated by a calibrator using an
SOz permeation tube traceable to an
NBS-SRM.
-------
Section 2.9.2
Sept. 1982
2.2 Calibration System
The calibration system consists of
two primary parts.
1 The temperature controlled
permeation device
2. A dynamic dilution system.
2.2.1 Temperature Controlled
Permeation System - The purpose of a
permeation system is to generate a
low S02 concentration at a constant
rate. This is done by holding a
permeation tube at a constant
temperature (±0.1°C)for which the
permeation rate is known. The SO2
permeating from this tube is carried
away by a low flow of gas (usually
clean dry air or N2) to a mixing
chamber where it is accurately diluted
with zero air to the concentration
desired.
2.2.2 Dynamic Dilution System - A
dynamic dilution system is required to
dilute the S02 output from either the
temperature-controlled permeation
system or an SO2 gas cylinder to the
desired concentration. All parts in
contact with the S02 output must be
glass or Teflon. The system must be
capable of controlling and measuring
flow rates to within ±2% of stated
flow.
2.3 Dynamic Multipoint
Calibration Principles
Dynamic calibration involves
introducing gas samples of known
concentrations to an instrument in
order to adjust the instrument to a
predetermined sensitivity and to derive
a calibration relationship. A minimum
of three reference points and one zero
point uniformly spaced covering 0 to
80 percent of the operating range are
recommended to define this
relationship.
The recommended method of
dynamically calibrating an S02
analyzer requires a certified
permeation tube traceable to an NBS-
SRM in a temperature controlled
environment (±0.1 °C) and diluent air
that is free of S02 (<0.001 ppm).
Temperature must be verified with an
NBS traceable thermometer prior to
calibration.
The permeation tube is held at a
constant temperature for a minimum
of 24 hours to allow the SO2 to diffuse
from the tube at a known rate. The low
flow of zero air that is passed over the
permeation tube serves as a carrier for
the S02. This purged air is then diluted
with different quantities of zero air to
generate the desired concentrations.
The analyzer's recorded response is
compared with the known
concentration to derive the calibration
relationship. This relationship is used
to convert the analyzer's responses
during sampling into ppm's of S02.
The recorded response may be either
voltage output or percent chart (%
chart) as long as it is consistent with
that used to determine the calibration
relationship.
Biweekly precision checks are used
to calculate the variability of the
calibration relationship over a period of
time. Three-point audits conducted
quarterly are used to check the
analyzer's accuracy. These precision
checks and the 3 (or 4) point audits are
used to generate precision/accuracy
data for the reporting organization.
They are not intended for use in
reducing or validating data since they
are performed infrequently. Level 1
zero and span checks must be used to
document withm-control conditions
and to validate the collected data.
2.4 Calibration Procedures
The procedures for multipoint
calibration of an SO2 analyzer by an
S02 permeation system are specified
in the Federal Register.1 To facilitate
these procedures, operational and
calculation data forms have been
developed as aids in conducting
calibrations and quality assurance
checks. Detailed descriptions of the
calibration theory and procedures for
S02 permeation systems are in the
Federal Register.1
Documentations of all data on the
station, instrument, calibrator,
reference standard, and calibration
procedures are of prime importance
since the validity of the data collected
by the instrument is dependent on the
quality of the calibration. Calibration
must be performed with a calibrator
that meets all conditions specified in
Subsection 2.2.
2.4.1 General Calibration
Recommendations - It is important that
the fluorescent analyzer be operated
during calibration under conditions
identical to those during normal
ambient air sampling. No modifications
or alterations shall be made to the
analyzer's components, flow system,
prescribed flow rate, or other
parameters. Concentrations of SO2
intended for calibration must be
generated continuously by means
entirely independent of the analyzer.
The flow rate of the calibration gas
must exceed the sample flow rate of
the analyzer. The calibration gas
should flow through a manifold, and
the analyzer should draw its sample
through the regular ambient air
sampling line, which is attached to a
port of the vented calibration manifold.
2.4.2 Calibration Procedure for SO2 -
The procedure for multipoint
calibration of a fluorescent analyzer is
necessarily general. That given here is
for fluorescent analyzers equipped
with a linearized output. Where
analyzer-specific explanations are
necessary, the reader is referred to the
manufacturer's instruction manual.
The following procedure using the
forms shown in Figures 2 1 and 2.2, is
given to aid in the collection and
documentation of calibration data.
1. Record the official name and
address of the station on the
form, where appropriate, the
name and address should be the
same as that appearing on the
SAROAD site identification form
to eliminate any confusion by
persons not familiar with the
station.
2. Identify the analyzer being
calibrated by the manufacturer's
name, model, and serial number.
3. Identify the person performing
the calibration and the date of
calibration
4. Identify the calibrator used. If
the calibrator was purchased,
record the manufacturer's name,
model and serial number.
Calibrators assembled by the
user should be assigned an
identification number so that
calibrations can be referenced to
that particular apparatus.
5. Identify, by supplier and tube
number, the reference standard
to be used. Provide a record of
NBS traceabihty for any tube
used in a calibration and include
the data of verification and the
name of the person who verified
the reference standard.
6. Identify the device used to
measure the flow of the dilution
air.
7. Record the barometric pressure
and the shelter temperature.
8. Record the analyzer sample air
flow.
9. Record the zero and span knob
settings after the calibration is
completed. (These settings can
be used as a basis of comparison
when changes are later
determined in the instrument
performance.)
10. Record the temperature at which
the permeation tube is
maintained during calibration
and use the recorded
-------
Sept. 1982
Section 2.9.2
temperature to determine the
SOz permeation rate (/L/g/min)
from the permeation tube data
form supplied by the
manufacturer. Record this value.
11. Measure and record the
temperature (AT) of the
calibrators air flow at the same
point that the flow rate
measurement is made.
12 If flow rates are measured using
a bubble meter or wet test meter
determine the vapor pressure of
water at temperature (AT) from
Table 2.1 and record.
Use calibration equations (Figure
2.1), the SOz calibration and linearity
check table, and the plot of the
calibration data (Figure 2.2) for
systematically recording the data
determined during the calibration of
the fluorescent S02 analyzer. Because
zero and calibration adjustments differ
among analyzers, the manufacturer's
manual should be consulted before
performing the following calibration
using Figure 2.2. References to
analyzer responses in the procedure
below refer to recorder responses.
1. Select the operating range of the
analyzer to be calibrated. See
the manufacturer's manual for
ranges for which the analyzer is
considered an equivalent
method.
2. Connect the recorder output
cable(s) of the analyzer to the
input terminals of the strip chart
recorder(s). All adjustments to
the analyzer should be
performed based on the
appropriate strip chart readings.
(Note: The recorder must be
operating properly prior to the
system calibration.)
3. Attach the analyzer sample line
to the output manifold of the
calibrator. Adjust the zero air
flow from the calibrator into the
analyzer. The zero air flow must
exceed the total demand of the
analyzer connected to the output
manifold to ensure that no
ambient air is pulled into the
manifold vent.
4. Allow the analyzer to sample
zero air until a stable response is
obtained (a response that does
not vary by more than ±2% over
a 5 min time period); then adjust
the analyzer zero control.
Offsetting the analyzer zero
adjustment to +5% of the strip
chart scale is recommended to
facilitate observing negative zero
drift. Record the stable zero air
response under column 4 of the
calibration table (Figure 2.2).
5. Determine the 80% URL of the
analyzer (e.g., for an operating
range of 0 to 0.5 ppm the 80%
URL would be 0.80 x 0.5 = 0.4
ppm).
6. Calculate the total air flow (Fr)
required to generate 0.4 ppm by
rearranging Equation 2-3 of
Figure 2.1 and by substituting
the known values,
FT = PR x ™
ppm SOz M
Equation 2-5
This flow rate will be in L/min
at STP.
7. Adjust the air dilution until the
total air flow (dilution air + purge
air) from the calibrator is that
determined in step 6; then
remeasure the total air flow, and
record its value on the 80% URL
line under column 1.
8. Calculate the STP correction
factor using Equation 2-1 and
record it
STP correction factor =
BP- VP 298
^760 X AT+273
Equation 2-1
A correction for vapor pressure
(VP) of water is made only if air
flow is measured with a bubble
tube or wet test meter.
9. Correct the measured total air
flow (F) to STP of 760 mm Hg
and 298K using Equation 2-2.
FT = F x STP correction factor
Equation 2-2
Record this value under column
2 of Figure 2.2.
10. Calculate the exact
concentration of SOz (ppm)
being generated using Equation
2-3.
PR MV
ppm [S02]°UT = — x —
rj M
Equation 2-3
Record this value on the 80%
URL line under column 3.
11. Calculate the required recorder
response for span adjust (80%
URL), using Equation 2-4.
[S02]OUT „„ ,
x 100+ZSO
i scale = •
URL
Equation 2-4
Allow the analyzer to sample
until the response is stable, and
then adjust the analyzer span
until the required recorder
response is obtained. (If
adjustment of the span control is
necessary, recheck the zero and
span adjustments by repeating
steps 4 through 10.) Record the
SOz recorder response on the 80
percent URL line under column
4.
12. After the zero and 80% URL
points have been set, determine
at least two approximately
evenly spaced points between
zero and 80 percent URL without
further adjustment to the
instrument. Generate these
additional points by increasing
the dilution flow. For each
concentration generated,
calculate the exact SOz
concentration by measuring the
total flow and by using
Equations 2-2 and 2-3. Check
the permeation tube
temperature before each
calibration point to determine if
changes larger than ±0.1 °C
have occurred. Record the
required information for each
point under the appropriate
column in the table of Figure
2.2.
13. Plot the analyzer responses (%
chart) on the y-axis versus the
corresponding calculated
concentrations [S0z]oui on the
x-axis to obtain the calibration
relationship as shown in Figure
2.2. Determine the straight line
of best fit (to all points including
the zero point) by using the
method of least squares (e.g.,
see Appendix J of Volume I of
this Handbook9). This
determination can be made with
a programmed calculator, or
with the calculation data form.
Figure 2.3. Because the time
required to manually perform
the calculation using the data
form is considerably longer than
that using a programmed
calculator, it is suggested that
the latter be used whenever
possible.
14. After determining the slope (b)
and the intercept (a) where the
line crosses the y-axis, draw the
fitted line for each set of points.
On the y-axis of the graph,
locate and plot the y intercept
(a). Using the equation Y = a +
bx, calculate the predicted value
(Y) using the 80% URL
concentration for the x value.
Plot this second point on the
graph. Draw a straight line
-------
Section 2.9.2
Sept. 1982
through these two points to give
a best-fit line. Figure 2.4 shows
a calibration line plotted using
this procedure.
15. After the best fit line has been
drawn for the SCb calibration,
determine whether the analyzer
response is linear, that is, no
calibration point should differ
from the best-fit line by more
than 2% of full scale. Perform a
simple test for linearity by
plotting a point 2% of scale
above and 2% of scale below the
points where the fitted line
crosses the 0.1 and 0.4 ppm
lines. Draw two straight lines,
one through the +2% points and
one through the -2% points
(Figure 2.4), to define the limits
between which the calibration
points can fall for the calibration
curve to be considered linear
Repeat any points falling outside
these limits to eliminate
calibration errors; if the repeated
points are still outside the limits,
consult the manufacturer's
manual on how to correct the
nonlmeanty
2.4.3 Example of a Calibration -
1. Complete items 1 through 8 of
Figure 2 1 to document
information concerning the
station, analyzer, calibrator
reference standard, and person
performing the calibration, and
consult the manufacturer's
operation manual before starting
the calibration.
2. Select the operating range of the
analyzer. For this example, we
will assume a 0 to 0.5 ppm
range.
3. Make sure that the recorder is
calibrated and operating properly
and is connected to the correct
output terminal of the analyzer.
4. Connect the analyzer's sample
line to the manifold of the
calibrator, and adjust the zero air
flow from the calibrator to
exceed the total flow demand of
the analyzer.
5. Allow the analyzer to sample the
zero air until a stable response is
obtained; adjust the analyzer
zero control; offset the analyzer
zero adjustments to +5% of
recorder scale to facilitate
observing negative zero drift
and record the stable zero air
responses of 5% under column 4
(Figure 2.2).
6. Calculate the STP correction
factor (Equation 2-1) by
substituting the known values in
item 1 3 of the calibration form.
The correction factor for this
example is 0.94.
7. Determine the 80% URL of the
analyzer For this example, it is
0.80 x 0.5 = 0.4 ppm. Now
calculate the flow rate needed to
generate 0.4 ppm by Equation
2-5, substituting the known
values.
1.54/ug/mm 24.45 L/mol
FT =
0.4 ppm
64 g/mol
1 47 I/mm at STP
F =
FT
= 1.56 L/mm at actual
0.94
conditions.
Adjust the dilution air until the
total air flow (dilution air + purge
air) from the calibrator is
approximately 1.56 I/mm.
Remeasure the total air flow and
record this value on the 80%
URL line under column 1.
Note: Make certain the flow of
calibration gas from the
calibrator exceeds the sample
flow rate of the monitor
Now correct the measured
flow (F) from step 7 to STP
conditions, using Equation 2-2,
FT = 1.56L/mmx0.94= 1.47
L/mm
Record this value under column
2 of the calibration table.
8. Calculate the exact concentration
of SCMppm) being generated,
using Equation 2-3.
ppm [SO2]ouj =
1.54/yg/mm
1 47 L/min
24.45 L/mol
64 g/mol
= 0.400 ppm
Record this value under column
3 of the calibration table.
9. Calculate the required recorder
response for span adjust (80%
URL) using Equation 2-4,
0.400 ppm , _.
% scale = ^-— x 100 +
0.5 ppm
5% = 85.0%
Allow the analyzer to sample
until the response is stable, and
then adjust the analyzer span
until the recorder response is
85.0% of scale. (If adjustment of
the span control is necessary,
recheck the zero and span
adjustments by repeating steps
5 through 9.) Record the S02
recorder response on the 80%
URL line under column 4.
Record the analyzers zero and
span knob settings under item 9
of the calibration form
10. Generate two evenly spaced
concentration points between
zero and the 80% URL by
increasing the total flow (FT).
Allow each trace to stabilize
before moving to the next
calibration point, and then
record the required information
in the appropriate column of the
SC>2 calibration table. Do not
readjust the analyzer zero or
span setting
11. Plot on Figure 2 2 the analyzer
response (% chart) from column
4 on the y-axis versus the
corresponding calculated
concentration [SOaJouTfrom
column 3 on the x-axis A
straight line of best fit is now
calculated by the method of least
squares For this example, the
slope (b) is determined to be 200
with a y-mtercept of 5%. The
calibration relationship is now
plotted as in Figure 2 3. To
determine linearity, draw +2%
and -2% lines parallel to the
calibration line For this
example, the analyzer response
is linear.
2.5 Calibration Frequency
To ensure accurate measurements
of the SOs concentrations, calibrate
the analyzer at the time of installation,
and recalibrate it.
1. No later than 3 mo after the most
recent calibration or performance
audit which indicated the analyzer
response to be acceptable or;
2. Following any one of the activities
listed below:
a. an interruption of more than a
few days in analyzer
operation,
b. any repairs,
c. physical relocation of the
analyzer, or
d. any other indication (including
excessive zero or span drift) of
possible significant inaccuracy
of the analyzer
Following any of the activities
listed in item 2 above, perform
Level 1 zero and span checks to
determine if a calibration is
necessary. If the zero and span
drifts do not exceed the calibration
limits in Table 9.1 of Section 2.0.9
(Subsection 9.1.3) (or stricter
limits set by the local monitoring
agency) a calibration need not be
performed. If either the zero or the
-------
Sept. 1982
Section 2.9.2
span drift exceeds its respective
limit, investigate the cause of the
drift, take corrective action, and
calibrate the analyzer. Individual
agencies may wish to use limits
which are tighter than those in
Table 9.1.
-------
Section 2.9.2
Sept. 1982
Calibration Data forms
Stat,on
2. Analyier
fin/ox C5ec*cg
Sr.
3. Calibration performed by
Dafe
50 E.
. 3
5. S02 standard
verified against NBS-SRM
By
11*2,1*
(C.Q
Date
6. Flow measured with
7 Barometric pressure
T&'
mm Hg Shelter temperature
fc V
°C
8 Analyzer sample flow readings
9 Zero knob setting
Span knob setting
O^ '
10 Permeation equilibrium temperature
Permeation rate (PR) _
2.5". O
pg/mm
1 1 Temperature at which air flow rate was measured (A J)
72 Vapor pressure of water at temperature I AT)
23. O
^*
°C
A** i
Equation 2-1
BP- VP 298
STP correction factor = - X -
760 AT + 273
Equation 2-2
Fr = F X STP correct/on factor
Equation 2-3
PR MV
ppm [SOJ our '= - x -
FT M
Equation 2-4
Response (% scale) = OUJ X 100 + Zso,
(JnL
Calibration Equations
BP = barometric pressure, mm Hg
VP = vapor pressure of water, mm Hg at AT (Table 2 1)
AT = temperature at which air flow rate was measured, °C
F = uncorrected flow rate
fr = total air flow rate, corrected to 25°C and 760 mm Hg. L/min
PR = permeation rate at equilibrium temperature, ug/min
MV = molecular volume of SO2 at 2S°C and 760 mm Hg 24.45 L/mol)
M = mo/ecu/ar weight of sc,2 {64 g/mol)
MV = 24.45 L/mol
M
=
Figure 2. 1 . Example of a calibration data form
64 g/mol
URL — upper range limit of analyzer
Zso, = recorder response to zero air
-------
Sept. 1982
Section 2.9.2
SO2 Calibration and linearity check.
Calibration
points
Zero
80% URL
1
2
1
F,
L/min
/.ft*
J.09
/3.0*
2a
Fr at STP
L/mm
Equation 2-2
/.V7
Z.90
iz.zo
3
ISOJour.
ppm
Equation 2-3
O-O
0.V00
O.aoZL
0-0*418
4
% Scale
Equation 2-4
s.o
&TO
vs:V
/V.6
13. FT = F X STP. STP
=(-
(730- C*0
760
Ill
I
&
100
90
80
70
60
50
30
20
10
0.10 0.20
0.30
0.40
Calibration Relationship
Slope (bj of calibration relationship (Y = a + bx) = ^__
Intercept fa} of calibration relationship = O /O
050
Figure 2,2. Example of a calibration data form (linearity check and calibration relationship).
-------
Section 2.9.2
Sept. 1982
Calibration
point
Zero
80% URL
1
2
3
4
X
O-OOO
O-VOO
O.J04
o-o^s
X2
O-OOO
O.I(fO
o.ov/
0.002
y
S".O
es.o
-------
Sept. 1982
Section 2.9.2
8
§
100
Limits for instrument
linearity check. ±2%
20
[SOJour.
Figure 2.4. Example of an SO2 calibration relationship
-------
Section 2.9.2
10
Sept. 1982
Table 2.1.
Temp.
°C
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
Table 2.2.
Calibration
activities
Saturation Vapor Pressure Over Water f°C, mm. Hg)
0.0
12.788
13.634
14.530
15.477
16.477
17.535
18.650
19.827
21.068
22.377
23.756
25.209
26. 739
28.349
30.043
31.824
33.695
35.663
37.729
39.898
42. 1 75
Activity Matrix
0.2
12.953
13.809
14 715
15673
16.685
17753
18.880
20.070
21.324
22.648
24.039
25.509
27.055
28.680
30.392
32.191
34.082
36.068
38.155
40.344
42.644.
0.4
13.121
13987
14.903
15.871
16.894
17.974
19.113
20316
21.583
22.922
24.326
25.812
27.374
29015
30. 745
32.561
34.471
36.477
38.584
40. 796
43.117
0.6
13.290
14.166
15.092
16.071
17 105
18.197
19.349
20.565
21.845
23.198
24.617
26.117
27.696
29.354
31.102
32.934
34.864
36.891
39.018
41.251
43.595
0.8
13.461
14.347
15.284
16.272
17.319
18.422
19.587
20.815
22.110
23.476
24.912
26.426
28.021
29.697
31.461
33.312
35.261
37.308
39.457
41.710
44.078
for Calibration Procedures
Acceptance
limits
A ction if
Frequency and method requirements
of measurement are not met
Permeation
tube
Dilution gas
Span gases
Multipoint
calibration
Traceable to /VflS stand-
ards
Zero-air free of con-
taminants; Sec 2.0. 7,
Subsec 7.1, andTAD'0
Cylinder gases cer-
tified to NBS-SRM or
commercial CRM cylin-
der gas or to an NBS-
SRM permeation tube
Gases generated by
calibrator using an
SOz permeation tube
Calibration proce-
dure in Subsec 2.2,
and the Federal
Register,1 completed
Figs 2.1 and 2.2
Subsec 2.0.7 for
frequency and method
TAD™
Assay against an
NBS-SRM semi-annually;
Sec 2.0. 7
Perform at least
once every quarter,
or anytime a level
span check indicates
a discrepancy, or
after maintenance
which may affect the
calibration; Subsec
2.5
Return to
supplier, or
make another
permeation tube
Return to
supplier, or take
corrective action
with generation
system
Working as
standard is
unstable and/or
measurement
method is out
of control; take
corrective action
(e.g., obtain new
span gases)
Repeat the
calibration
-------
Sept. 1982
Section 2.9.3
3.0 Operation and Procedure
Essential to quality assurance are
scheduled checks for verifying the
operational status of the monitoring
system. At least once each week the
operator should visit the site. Every
two weeks, Level 1 zero and span
checks must be made on the analyzer.
Level 2 zero and span checks should
be conducted at a frequency desired by
the user. Level 1 and 2 checks are
described in-depth in Section 2.0.9 of
this Handbook.
At least once every two weeks, an
independent precision check at a
concentration between 0.08 and 0.10
ppm SO2 must be conducted. Table 3.1
at the end of this section summarizes
the quality assurance activities for the
routine operations discussed in the
following sections.
For documentation and
accountability of activities, a checklist
should be compiled and then filled out
by the field operator as each activity is
completed. A simplified example
checklist is given in Figure 3.1. A more
comprehensive check list should be
developed for specific sampling
stations.
In Subsections 3.1 and 3.2,
reference is made to the sampling
shelter and the sample inlet system,
but the design and construction of
these components are not within the
scope of this Handbook. For more
information refer to an in-depth study
of these in Reference 11.
3.1 Shelter
The shelter's role in quality
assurance is to provide a temperature-
controlled environment in which the
sampling equipment can operate at its
optimum. The mean shelter
temperature should be between 22°
and 28°C (72° and 82°F). A
thermograph should be installed at the
shelter to continuously record daily
fluctuations in temperature.
Fluctuations greater than ±2°C (±4°F)
may cause the electronic components
of the analyzer to drift and may
introduce error into the data.
Fluctuations outside of these limits
should be identified, and the data for
the affected time period should be
flagged to indicate possible
discrepancies.
3.2 Sample Introduction
System
The sample introduction system
consists of an intake port, the
paniculate and moisture traps, the
sampling manifold and blower, and the
sampling line to the analyzer. The field
operator, as part of the quality
assurance program, should inspect
each of these components for
breakage, leaks, and buildup of
paniculate matter or other foreign
objects; check for moisture deposition
in the sample line or manifold; see that
the sample line is connected to the
manifold; see that any component of
the sample introduction system that is
not within tolerance is either cleaned
or replaced immediately. See Section
2.0.2 for more details.
3.3 Recorder
During each weekly visit to the
monitoring site, the field operator
should use the following list to check
the recorder for proper operation:
1. Ink trace for legibility
2. Ink level in reservoir
3. Chart paper for supply
4. Chart speed control setting
5. Signal input range switch
6. Time synchronization.
Any operational parameter that is not
within tolerance must be corrected
immediately.
3.4 Analyzer
Specific instructions in the
manufacturer's manual should be read
thoroughly before attempting to
operate the analyzer As part of the
quality assurance program, each site
visit should include a visual inspection
of the external parameters of the
analyzer, the zero and span checks;
and a biweekly precision check when
applicable.
3.4.1 Visual Inspection - The field
operator should inspect the external
operating parameters of the analyzer;
these will vary from instrument to
instrument, but in general they will
include the following:
1. Correct settings of flow meters
and regulators.
2 Cycling of temperature control
indicators.
3. Temperature level, if equipped
with a pyrometer.
4. Verification that the analyzer is in
the sampling mode rather than the
zero or the calibration mode.
5. Zero and span potentiometers
locked and set at proper values.
3.4.2 Zero and Span Checks - Zero
and span checks must be used to
document within-control conditions
and to provide interim checks on the
response of the instrument to known
concentrations. A quality control chart
can be used to provide a visual check
to determine if the analyzer is within
control conditions. If a response is
outside of the prescribed limits, the
analyzer is out of control and the
cause must be determined and
corrected. A zero check should be
conducted at the same time that the
span check is performed.
Level 1 and Level 2 zero and span
checks are recommended and must be
conducted in accordance with
Subsection 9.1 of Section 2.0.9. Level
1 zero and span checks must be
conducted every two weeks. Level 2
checks should be conducted between
the Level 1 checks at a frequency
desired by the user. Span
concentrations for either Level 1 or 2
checks should be between 70% and
90% of the measurement range. The
data should be recorded on the zero
and span check form, Figure 3.2.
Zero and span checks are used to
provide:
1. Data to allow analyzer adjustment
for zero and span drift
2. A decision point for calibrating the
analyzer
3. A decision point for invalidating
the monitoring data.
Items 1 and 2 are described in detail in
Subsection 9.1.3 of Section 2.0.9 and
item 3 is described in Subsection 9.1.4
of the same section.
When the response from a span
check is outside of the control limits,
the cause for the extreme drift should
be determined, and corrective action
should be taken. Some of the causes
for drift are:
1. Lack of preventive maintenance
2 Fluctuations in electrical power
supply
3. Major fluctuations in sample flow
4. Change in zero air source
5. Change in span gas concentration
6. Degradation of photomultiplier
tube
-------
Section 2.9.3
Sept. 1982
7. Degradation of UV light source
8. Electronic and physical
components not within
manufacturer's specifications.
Corrective actions for the above can be
found in the manufacturer's
instruction/operations manual
3.4.3 Precision Check - For
continuous analyzers, periodic checks
are used to assess the data for
precision. A one-point precision check
must be carried out at least once every
2 weeks on each analyzer at an S02
concentration between 0.08 and 0.10
ppm. The analyzer must be operated in
its normal sampling mode, and the
precision test gas must pass through
all filters, scrubbers, conditioners, and
other components used during normal
ambient sampling. The standards from
which precision check test
concentrations are obtained must be
traceable to NBS-SRM's or NBS/EPA-
approved commercially available
Certified Reference Material (CRM).
Direct use of a CRM as a working
standard is acceptable, but direct use
of an NBS-SRM as a working standard
is discouraged because of the limited
supply and expense of SRM's.
Standards used for calibration may
also be used. The precision check
procedure is as follows:
1. Connect the analyzer to a
precision gas that has a
concentration between 0.08 and
0.10 ppm. An SC>2 precision gas
may be generated by an SQz
permeation tube or by dilution of a
high concentration (50 to 100
ppm) SO2 standard gas. If a
precision check is made with a
zero and span check, it must be
made prior to any zero or span
adjustments.
2. Allow the analyzer to sample the
precision gas until a stable trace is
obtained at the recorder.
3. Record this value on the precision
check data form (Figure 3.3), and
mark the chart as "unadjusted
precision check." Information from
the check procedure is used to
assess the precision of the
monitoring data; see Section 2.0.8
for procedures for calculating and
reporting precision.
-------
Sept. 1982
Section 2.9.3
1. Inspect thermograph for temperature variations greater than ±2°C (4°F). Identify time frame of any temperature level
2. Inspect sample introduction system for moisture, paniculate buildup, foreign objects, breakage, and leaks.
Comments:
OF
/A/ T&*f*
3.
Check to see if sample line connected to manifold.
Comments:
4 Inspect data recording system
• Legibility of trace
• Ink supply
• Paper supply
• Chart speed selector
• Signal input range switch
• Time synchronization
Comments
OK
Corrective
action taken
5. Inspect analyzer's operational parameters
• Sample flow rate
• Oven temperature light flashing
• Analyzer in sample mode
• Zero and span potentiometers locked at
correct setting
OK
Corrective
action taken
Comments:
6.
7.
Zero the analyzer
Check to see if unadjusted zero is within tolerance
Comments. Zg£O O/CAV AT
-------
Section 2.9.3 4 Sept. 1982
12. Record cylinder pressure of zero and span tanks.
Zero air
13. Close valves on zero and span tanks.
Signature of technician ••_»• •- y j—j
Figure 3.1. Example of an operational checklist /backside).
-------
Sept. 1982
Section 2.9.3
Site ID v-^vy/ Pollutant ^J ^ f-
Location t*f(JN '/C,/PAL lMCt*/€MlOA* Analyzer F • WOft g.5C€"A/C€
Address 3 3 3(f JfZFF£ft£&N H VE . Serial number Iff C/ • C/
>^c//i/sfedze
Dare
Z-l-So
ro «5" VO Adiusted span O& ' O O F C H&&-1
Time
Operator
Unadjusted
zero,
% chart
Span
concentration,
ppm
Unadjusted
span,
% chart
8V
Figure 3.2. Example of a Level 1 zero and span check data form.
-------
Section 2.9.3
Sept. 1982
Site ID OO/ Pollutant
JO *
Location n/VMlCJPAL /A/CWC/?H7DH Analyzer F"LUO&€S CCA/C6T
4<*/r«ss 33*b J£FF&lSQN AVC. Serial number
V7/0.O
Date
^•Mo
Time
/050
Operator
46 C.
Precision
test gas
concentration.
ppm
o./o
Analyzer
response.
% chart
x.1
ppm
o-ol*
Difference".
ppm
-Q.OO?
"Difference = analyzer response • test gas concentration.
Figure 3.3. Example of precision check form.
-------
Sept. 1982
Section 2.9.3
Table 3.1.
Daily Activity Matrix
Characteristic
Acceptance limits
Frequency and method
of measurement
Action if
requirements
are not met
Shelter temper-
ature
Sample intro-
duction system
Recorder
Analyzer oper-
ational set-
tings
Analyzer oper-
ational check
Precision
check
Mean temperature be-
tween 22° and 28°C
(72° and 82° F), daily
fluctuations not
greater than ±2°C (4°F)
No moisture, foreign
material, leaks, or ob-
structions; sample line
connected to manifold
Adequate ink and chart
paper; legible ink
traces; correct
settings of chart
speed and range
switches; correct
time
Flow and regulator
indicators at proper
settings; temperature
indicators cycling or
at proper levels;
analyzer set in
sample mode; zero and
span controls locked
Zero and span within
tolerance limits;
Subsec 9.1.3 of Sec
2.0.9
Precision assessed as
described in Sec 2.0.8
and Subsec 3.4.3'
Edit thermograph
chart daily for
variations greater
than ±2°C (4°F)
Visually inspect
weekly
Visually inspect
weekly
Visually inspect
weekly
Check level 1 zero
and span every 2
weeks; check Level 2
between Level 1
checks at frequency
desired by user
Check every 2 weeks,
Subsec 3.4.3
Mark strip chart
for the affected
time period;
repair or adjust
temperature
control system
Clean, repair,
or replace
as needed
Replenish ink
and chart paper;
adjust recorder
time to agree
with clock;
note on chart
Adjust or repair
as needed
Isolate source
of error, and
repair; then
recalibrate
the analyzer
Calculate;
report precision;
Sec 2.0.8
-------
Sept. 1982
Section 2.9.4
4.0 Data Reduction, Validation, and Reporting
This section is the same as that of
Section 2.5.4. Table 4.1 summarizes
the quality assurance activities for the
data reduction, validation, and
reporting.
Table 4.1. Activity Matrix for Data Reduction. Validation, and Reporting
Activity
Data reduction
Acceptance limits
Stepwise procedure,
Subsec 4. 1
Frequency and method
of measurement
Follow the method
in Subsec 4. 1
Action if
requirements
are not met
Review the
reduction
procedure
Data validation
Span drift
check
Strip chart
edit
Data reporting
Level 1 span drift
check <2S%, Sec
2.0.9
No sign of malfunc-
tion
Data transcribed to
SAROAD hourly data
form; Ref 13
Check at least every
2 weeks; Sec 2.5.3;
Ref 12 recommends
screening procedures
to identify gross
anomalies
Visually edit each
strip chart; Subsec
4.2
Visually check
Invalidate data;
take corrective
action; increase
frequency of
Level 1 checks
until data
are acceptable
Void data for
time interval
for which
malfunction
detected
Review the
data transcribing
procedure
-------
Sept. 1982 1 Section 2.9.5
5.1 Preventive Maintenance
Because maintenance requirements
vary from instrument to instrument,
the supervisor should refer to the
manufacturer's manual for a specific
analyzer. After becoming familiar with
these requirements, the supervisor
should develop a suitable preventive
maintenance schedule.
5.2 Corrective Maintenance
Corrective maintenance is defined
as nonscheduled activities that
become necessary due to system
malfunctions. A few examples of
corrective maintenance are: replacing
a damaged pump diaphragm; cleaning
a clogged sampling line; and replacing
the selective scrubber for aromatic
hydrocarbons. The need for corrective
maintenance becomes apparent as the
operator performs the operations
described in Section 2.9.3. When the
need for corrective maintenance
arises, the operator should refer to the
owner's manual for troubleshooting
procedures. A detailed record of
corrective maintenance activities
should be kept on file for each analyzer
at the site to identify recurring
malfunctions; maintenance log
appears in Figure 5.1.
Caution: When replacing, aligning,
and otherwise servicing the deuterium
source lamp, always wear UV-
absorbing glasses to protect the eyes
from the ultraviolet radiation produced.
Ordinary prescription spectacles with
glass lenses are suitable. Plastic
lenses may not provide adequate
protection.
5.0 Maintenance
-------
Section 2.9.5
Sept. 1982
Site number
Site location
Site address
OOl
. Pollutant
fllyniti PA ( In c/
__ Instrument
Fluorescence
33,3 fc JeFF6*Sotf
_ Serial number
288-70***"-S
Date
Technician
Event
initiating
maintenance
Maintenance
activity
Comments
2-/-80
Loss
UV
•fill
ba^
tijhi source.
figure 5.1. Analyzer maintenance log
-------
Sept. 1982
Section 2.9.6
6.0 Auditing Procedure
Table 6.1 summarizes the quality
assurance activities for audits. This
section is the same as Section 2.5.6.
See References 14 and 15 for the
frequency and brief descriptions of
audit procedures.
Table 6.1. A ctivity Matrix for A udit Procedure
Audit
Acceptance limits
Frequency of method
of measurement
Action if
requirements
are not met
Multipoint
calibration
audit
Data reduction
audit
Systems audit
Difference between
measured and audit
values is used as mea-
sure of accuracy; Sec
2.0.8
Step wise procedures for
data reduction, Subsec
6.2; no audit dif-
ference exceeding
±0.02 ppm
Method in this sec-
tion of the Handbook
Perform at least once
a quarter; Subsec
6.1.3 for procedure
Perform independent
data processing check
on a sample of the
recorded data; check
1 day of every 2
weeks of data, 2
hours each day
At startup of new
monitoring system.
and periodically
observe as appropri-
ate,' checklist.
Fig 6. 4
Recalibrate
the analyzer
Check all re-
maining data
if one or
more data re-
duction checks
exceed ±0.02
ppm
Initiate
improved
methods and/
or training
programs
-------
Sept. 1982 1 Section 2.9.7
7.0 Assessment of Monitoring Data for Precision and Accuracy
For continuous analyzers, in
SLAMS, NAMS, or PSD networks a
biweekly check is performed to
determine if the measurement process
is within control and to assess the data
for precision. These data can be used
to calculate estimates of single
instrument precision, and reporting
organization precision as prescribed in
Section 2.0.8 of this volume of the
Handbook. The precision check
procedures described in Section 2.9.3,
Subsection 3.4.3 are consistent with
those in References 14 and 15.
Estimates of single instrument
accuracy as well as reporting
organization accuracy for ambient air
quality measurements from
continuous methods are based on the
results of the in-depth accuracy audit
and are calculated according to the
procedure in Section 2.0.8. The audit
is described in Section 2.9.6.
-------
Sept. 1982 1 Section 2.9.8
8.0 Recommended Standards for Establishing Traceability
To achieve data of desired quality,
two considerations are essential:
1. The measurement process must
be in statistical control at the time
of the measurement, and
2. The systematic errors, when
combined with the random
variation in the measurement
process, must result in an
acceptable uncertainty.
As evidence in support of good quality
data, it is necessary to perform quality
control checks and independent audits
of the measurement process; to
document these data (e.g., by means of
specific data forms or a quality control
chart); and to use materials,
instruments, and measurement
procedures that can be traced to
appropriate standards of reference.
Data must be routinely obtained by
repeat measurements of standard
reference samples (primary, secondary,
and/or working standards), and a
condition of process control must be
established. The working standards
must be traceable to either NBS-
SRM's or commercially available
CRM's, such as those listed below:
NBS-SRM's Available for Use in Establishing Traceability of Permeation Tubes8
SRM
1625
1626
1627
Type
SO2 permeation
SO 2 permeation
S02 permeation
tube
tube
tube
Tube
length,
cm
10
5
2
Nominal
permeation
rate.
pg/min at 25°C
2.8
1.4
0.56
NBS-SRM's Available for Use in Establishing Traceability of Compressed
Cylinder Gases
Nominal
SRM Type concentration
1693 S02inN2 50 ppm
1694 SO2inN2 100 ppm
A list of gas manufacturers who
have approved CRM is available by
writing to:
U.S. Environmental Protection
Agency
Environmental Monitoring Systems
Laboratory (MD-77)
Research Triangle Park, North
Carolina 27711
ATTN: List of CRM Manufacturers
-------
Sept. 1982 1 Section 2.9.9
9.0 Equivalent Method
A method description is not given
herein. The concepts of equivalent
analyzers are discussed in Section
2.0.4 of this volume of the Handbook.
The analyzer must also comply with
the performance specifications in
Table 4.1 of Section 2.0.4. An
instruction manual including the
calibration procedure must accompany
the analyzer when it is delivered to the
purchaser. This instruction manual
has been reviewed and approved by
EPA as part of the equivalency test
program. The user of the analyzer
should use the method description in
this section of the Handbook and the
instruction manual.
A list of equivalent methods may be
obtained from any EPA regional office
or from the Environmental Monitoring
Systems Laboratory, Department E,
MD-77, Research Triangle Park, N.C.
27711. Any analyzer offered for sale
as an equivalent method after April 16,
1976, must bear a label indicating this
designation by EPA.
-------
Sept. 1982
Section 2.9.10
10.0 References
10.
11.
Code of Federal Regulations 40.
Protection of the Environment.
Parts 50 to 69. Revised July 1,
1977
Summary of Performance Test
Results and Comparative Data
for Designated Equivalent
Methods for S02, EPA Document
No. QAD/M-79.12.
Thermo Electron Corporation,
Environmental Instruments
Division Instruction Manual
Model 43 Pulsed Fluorescent
SO2 Analyses Equipped with an
Aromatic Hydrocarbon Cutter.
TE5405-112-77, Revision C.
Hopkmton, Massachusetts.
Beckman Instruments, Inc.
Beckman Model 953 Fluorescent
Ambient Sulfur Dioxide
Analyzer. Fullerton, CA. May
1979.
Monitor Labs, Inc. Monitor Labs,
Inc. Model 8850 Fluorescent
SOa Analyzer Instruction
Manual. Document 8850 Rev. D.
San Diego, CA. September
1979.
Columbia Scientific Industries
Corp. Fluorescent Sulfur Dioxide
Analyzer Model SA700
Operation, Maintenance, and
Parts Manual. Meloy
Laboratories, Inc. Springfield,
Virginia. 1980 and 1981.
Scarmgelli, F P., O'Keefe, A. E.,
Rosenberg, E. and Bell, J. P.,
"Preparation of Known
Concentrations of Gases and
Vapors with Permeation Devices
Calibrated Gravimetrically",
Analytical Chemistry, 42, 871
(1970)
Catalog of NBS Standard
Reference Materials. NBS
Special Publication 260, 1981 -
83 Edition. U.S. Department of
Commerce, NBS, Washington,
D.C. November 1981.
Quality Assurance Handbook for
Air Pollution Measurement
Systems. Vol. I. EPA-600/9-76-
005. March 1976
Use of the Flame Photometric
Detector Method for
Measurement of Sulfur Dioxide
in Ambient Air, A Technical
Assistance Document, EPA-
600/4-78-024, May 1978.
Field Operations Guide for
Automatic Air Monitoring
Equipment. U.S. Environmental
Protection Agency, Office of Air
Programs; October 1972.
Publication No. APTD-0736, PB
202-249, and PB 204-650.
12. U.S. Environmental Protection
Agency, Sreening Procedures for
Ambient Air Quality Data. EPA-
450/2-78-037, July 1978.
13. AEROS Manual Series, Volume
II: AEROS Users Manual, U.S.
Environmental Protection
Agency, Research Triangle Park,
N.C., EPA-450/2-76-029,
OAQPS No. 1.2 - 039, December
1976.
14. Appendix A - Quality Assurance
Requirements for State and
Local Air Monitoring Stations
(SLAMS), Federal Register, Vol.
44, No. 92, pp. 27574-27582,
May 1979.
15. Appendix B - Quality Assurance
Requirements for Prevention of
Significant Deterioration (PSD)
Air Monitoring, Federal Register.
Vol. 44, No. 92, pp. 27582
27584, May 1979.
-------
Sept. 1982
Section 2.9.11
Blank data forms are provided on the
following pages for the convenience of
the Handbook user. Each blank form
has the customary descriptive title
centered at the top of the page.
However, the section-page
documentation in the top right-hand
corner of each page of other sections
has been replaced with a number in
the lower right-hand corner that will
enable the user to identify and refer to
a similar filled-in form in a text
section. For example, Form SO2 (FLR)-
2.1 indicates that the form is Figure
2.1 of the S02 (FLR) method
description. Future revisions of this
form, if any, can be documented by
2.1 A, 2.1B, etc. Only the data forms
that are distinct from those of Section
2.5.11 are included here; however, all
of the data forms are listed below.
Form
11.0 Data Forms
Title
1.1 (see 2.5.11)
2.1
2.2 (see 2.5.11)
2.3 (see 2.5.11)
3.1
3.2 (see 2.5.11)
3.3 (see 2.5.11)
4.1 (see 2.5.11)
5.1 (see 2.5.11)
6.1 (see 2.5.11)
6.2 and 6.3 (see
2.5.11)
6.4 (see 2.5.11)
Procurement Log
Calibration Data Form
Example of a Calibration Data Form
Calculation Form for the Method of
Least Squares
Operational Checklist
Span Check Data Form
Precision Check Form
Data Form for Recording Hourly
Averages
Maintenance Log
Audit Summary Form
Audit Calculation Form
Checklist for Use by Auditor
-------
Section 2.9.11
Sept. 1982
J. Station
Calibration Data Form
2. Analyzer
3. Calibration performed by.
4. Calibrator used
5. SO} standard
verified against NBS-SRM
By
6. Flow measured with
7. Barometric pressure
8. Analyzer sample flow readings
9 Zero knob setting
10. Permeation equilibrium temperature
Permeation rate (PR)
Date
.Date
mm Hg Shelter temperature .
Span knob setting
fjg/min
11. Temperature at which air flow rate was measured (A T)
12. Vapor pressure of water at temperature (AT)
Calibration Equations
mm Hg
298
Equation 2-1
STP correction factor =
760 AT + 273
Equation 2-2
FT — F X STP correction factor
Equation 2-3
PR MV
ppm [SOJ OUT = x
FT M
Equation 2-4
Response (% scale) = l °JouT X TOO + Zso,
URL
BP = barometric pressure, mm Hg
VP = vapor pressure of water, mm Hg at AT fTable 2.1)
AT = temperature at which air flow rate was measured, °C
F — uncorrected flow rate
FT = total air flow rate, corrected to 2S°C and 760 mm Hg. L/min
PR = permeation rate at equilibrium temperature, yg/min
MV = molecular volume of SO2 at 25°C and 760 mm /Hg 24.45 L/mol)
M = molecular weight of SO2 (64 g/r
MV _ 24.45 L/mol
M
= 0.382 L/g
64 g/mol
URL = upper range limit of analyzer
Zso, = reorder response to zero air
Quality Assurance Handbook SO2 (FLR)-2.1
-------
Sept. 1982 3 Section 2.9.11
Operational Checklist IFrontside)
Site ID _ Date —_
Site name Technician
Site address
1 Inspect thermograph for temperature variations greater than ±2°C f4°F). Identify time frame of any temperature level
out of tolerance
Comments: -——
2. Inspect sample introduction system for moisture, paniculate buildup, foreign ob/ects. breakage, and leaks.
Comments: ^^____
3. Check to see if sample line is connected to manifold.
Comments: .
4. Inspect data recording system.
Corrective
OK action taken
• Legibility of trace
• Ink supply
• Paper supply
• Chart speed selector
• Signal input range switch
• Time synchronization
Comments • .
5 Inspect analyzer's operational parameters
Corrective
OK action taken
• Sample flow rate
• Oven temperature light flashing
• Analyzer in sample mode
Zero and span potentiometers locked at
correct setting
Comments
6. Zero the analyzer
7 Check to see if unadjusted zero is within tolerance
Comments
8 Span the analyzer
9. Check to see if unadjusted span is within tolerance
Comments
. 10. Enter zero and span values on span check data form
. 11 Return to sample mode
Quality Assurance Handbook SOi (FLRI-3. t
-------
Section 2.9.11
12. Record cylinder pressure of zero and span tanks.
Zero air
Span air
Sept. 1982
13 Close valves on zero and span tanks.
Signature of technician
-------
United States Environmental Monitoring Systems
Environmental Protection Laboratory
Agency Research Triangle Park NC 27711
Research and Development EPA-600/4-77-027b Feb 1984
V>EPA Quality Assurance
Handbook for
Air Pollution
Measurement
Systems: Volume III.
Stationary Source
Specific Methods
Addition Section 3.12
-------
Jan. 1984
Section
30
30.1
302
303
304
305
306
307
3 1
3 1 1
3 1 2
3.1 3
3 1 4
3 1 5
3 1 6
3 1 7
3 1 8
3 1.9
3 1 10
3111
3 1 12
32
32 1
322
323
324
325
326
Volume III
Table of Contents
Purpose and Overview of the
Quality Assurance Handbook
General Aspects of Quality
Assurance for Stationary
Source Emission Testing
Programs
Planning the Test Program
General Factors Involved
in Stationary Source Testing
Cham-of-Custody Procedure
for Source Sampling
Traceability Protocol for
Establishing True Concen-
tration of Gases Used for
Calibration and Audits of
Continuous Source Emission
Monitors (Protocol No 1)
Specific Procedures to
Assess Accuracy of Refer-
ence Methods Used for
SPNSS
Specific Procedures to
Assess Accuracy of Ref-
erence Methods Used for
NESHAP
Interpretation and Appli-
cation of CEM Precision
and Accuracy Data
Method 2 — Determination of Stack
Gas Velocity and Volumetric Flow
Rate
Procurement of Apparatus
and Supplies
Calibration of Apparatus
Presamplmg Operations
On-Site Measurements
Postsamplmg Operations
Calculations
Maintenance
Auditing Procedure
Recommended Standards for
Establishing Traceability
Reference Method
References
Data Forms
Method 3 — Determination of Carbon
Dioxide, Oxygen, Excess Air, and
Dry Molecular Weight
Procurement of Apparatus
and Supplies
Calibration of Apparatus
Presamplmg Operations
On-Site Measurements
Postsamplmg Operations
Calculations
Pages
3
Date
1-04-82
11
2
7
3
5-01-79
5-01-79
5-01-79
6-15-78
Currently under
development
Currently under
development
Currently under
development
15
21
7
12
3
4
1
5
1
11
2
8
15
4
6
12
2
3
1-15-80
1-15-80
1-15-80
1-15-80
1-15-80
1-15-80
1-15-80
1-15-80
1-15-80
1-15-80
1-15-80
1-15-80
1-15-80
1-15-80
1-15-80
1-15-80
1-15-80
1-15-80
-------
Jan. 1984
Table of Contents (continued)
Section Pages Date
3.2.7 Maintenance 1 1-15-80
3.2.8 Auditing Procedure 5 1-15-80
3.2.9 Recommended Standards for 1 1-15-80
Establishing Traceability
3.2.10 Reference Method 3 1-15-80
3.2.11 References 1 1-15-80
32.12 Data Forms 6 1-15-80
3.3 Method 4 — Determination of
Moisture in Stack Gases
3.3.1 Procurement of Apparatus 9 1-15-80
and Supplies
3.3.2 Calibration of Apparatus 19 1-15-80
33.3 Presamplmg Operations 7 1-15-80
3.3.4 On-Site Measurements 10 1-15-80
3.3.5 Postsamphng Operations 4 1-15-80
33.6 Calculations 8 1-15-80
3.37 Maintenance 3 1-15-80
33.8 Auditing Procedure 4 1-15-80
33.9 Recommended Standards for 1 1-15-80
Establishing Traceability
33.10 Reference Method 5 1-15-80
33.11 References 1 1-15-80
33.12 Data Forms 14 1-15-80
3.4 Method 5 — Determination of Par-
ticulate Emissions from Stationary
Sources
3.41 Procurement of Apparatus 15 1-15-80
and Supplies
342 Calibration of Apparatus 22 1-15-80
3.43 Presamplmg Operations 20 1-15-80
3.4.4 On-Site Measurements 19 1-15-80
345 Postsampling Operations 15 1-15-80
3.4.6 Calculations 10 1-15-80
3.47 Maintenance 3 1-15-80
3.4.8 Auditing Procedure 7 1-15-80
349 Recommended Standards for 1 1-15-80
Establishing Traceability
3.410 Reference Method 6 1-15-80
34.11 References 2 1-15-80
3.4.12 Data Forms 21 1-15-80
3 5 Method 6 — Determination of
Sulfur Dioxide Emissions from
Stationary Sources
3.5.1 Procurement of Apparatus 6 5-01-79
and Supplies
35.2 Calibration of Apparatus 6 5-01-79
3.5.3 Presamplmg Operations 3 5-01-79
3.5.4 On-Site Measurements 7 5-01-79
3.55 Postsampling Operations 7 5-01-79
3.5.6 Calculations 2 5-01-79
3.5.7 Maintenance 1 5-01-79
3.5.8 Auditing Procedure 3 5-01-79
3.5.9 Recommended Standards for 1 5-01-79
Establishing Traceability
-------
Jan. 1984
Table of Contents (continued)
Section Pages Date
3.510 Reference Method 4 5-01-79
35.11 References 1 5-01-79
3512 Data Forms 13 5-01-79
3 6 Method 7 — Determination of
Nitrogen Oxide Emissions from
Stationary Sources
361 Procurement of Apparatus 5 5-01-79
and Supplies
362 Calibration of Apparatus 5 5-01-79
363 Presamplmg Operations 5 5-01-79
364 On-Site Measurements 8 5-01-79
365 Postsamplmg Operations ^ 5-01-79
366 Calculations 4 5-01-79
367 Maintenance 1 5-01-79
368 Auditing Procedure 4 5-01-79
369 Recommended Standards for 1 5-01-79
Establishing Traceabihty
3610 Reference Method 5 5-01-79
3611 References 1 5-01-79
3612 Data Forms 13 5-01-79
3 7 Method 8 — Determination of
Sulfuric Acid Mist and Sulfur
Dioxide Emissions from Stationary
Sources
371 Procurement of Apparatus 7 5-01-79
and Supplies
372 Calibration of Apparatus 10 5-01-79
373 Presamplmg Operations 4 5-01-79
374 On-Site Measurements 10 5-01-79
37.5 Postsamplmg Operations 9 5-01-79
37.6 Calculations 6 5-01-79
377 Maintenance 2 5-01-79
378 Auditing Procedure 3 5-01-79
379 Recommended Standards for 1 5-01-79
Establishing Traceability
3710 Reference Method 5 5-01-79
3711 References 1 5-01-79
3712 Data Forms 17 5-01-79
3 8 Method 10 — Determination of Carbon
Monoxide Emissions from Stationary
Sources
381 Procurement of Apparatus 13 1-04-82
and Supplies
382 Calibration of Apparatus 18 1-04-82
3.8.3 Presamplmg Operations 6 1-04-82
384 On-Site Measurements 12 1-04-82
3.85 Postsamplmg Operations 5 1-04-82
386 Calculations 3 1-04-82
3.87 Maintenance 2 1-04-82
388 Auditing Procedure 7 1-04-82
3.89 Recommended Standards for 7 1-04-82
Establishing Traceability
3.8.10 Reference Method 3 1-04-82
3.8.11 References 2 1-04-82
3.812 Data Forms 11 1-04-82
-------
Jan. 1984
Table of Contents (continued)
Section Pages Date
3.9 Method 13B — Determination of Total
Fluoride Emissions from Stationary
Sources (Specific-Ion Electrode
Method)
3.9.1 Procurement of Apparatus 20 1-04-82
and Supplies
3.9.2 Calibration of Apparatus 25 1-04-82
3.9 3 Presamplmg Operations 6 1 -04-82
39.4 On-Site Measurements 21 1-04-82
3.9.5 Postsampling Operations 19 1-04-82
3.96 Calculations 7 1-04-82
3.9.7 Maintenance 3 1-04-82
3.9.8 Auditing Procedures 8 1 -04-82
39.9 Recommended Standards for 1 1-04-82
Establishing Traceability
39.10 Reference Method 2 1-04-82
3.9 11 References 1 1 -04-82
3.912 Data Forms 22 1-04-82
3.10 Method 13A — Determination of Total
Fluoride Emissions from Stationary
Sources (SPADNS Zirconium Lake
Method)
3.10.1 Procurement of Apparatus 13 1-04-82
and Supplies
3.10.2 Calibration of Apparatus 5 1-04-82
3.103 Presampling Operations 3 1-04-82
3104 On-Site Measurements 3 1-04-82
3.10.5 Postsampling Operations 18 1-04-82
3106 Calculations 7 1-04-82
3.10.7 Maintenance 2 1-04-82
3.108 Auditing Procedures 1 1-04-82
3.10.9 Recommended Standards for 1 1-04-82
Establishing Traceability
3.10.10 Reference Method 5 1-04-82
3.10.11 References 1 1-04-82
3.1012 Data Forms 6 1-04-82
3.11 Method 17 — Determination of
Paniculate Emissions from
Stationary Sources (In-Stack
Filtration Method)
3.111 Procurement of Apparatus 9 1-04-82
and Supplies
3.11.2 Calibration of Apparatus 2 1-04-82
3.11.3 Presamplmg Operations 3 1-04-82
3.11.4 On-Site Measurements 6 1-04-82
3.11.5 Postsampling Operations 1 1-04-82
3.11.6 Calculations 1 1-04-82
3.11.7 Maintenance 2 1-04-82
311.8 Auditing Procedure 2 1-04-82
3.11.9 Recommended Standards for 1 1-04-82
Establishing Traceability
3.1110 Reference Method 11 1-04-82
3.11.11 References 1 1-04-82
3.11.12 Data Forms 1 1-04-82
-------
Jan. 1984
Table of Contents (continued)
Section Pages Date
3.1 2 Method 9 — Visible Determination
of the Opacity of Emissions from
Stationary Sources
3.12.1 Certification and Training of
Observers 5 4-20-83
3.122 Procurement of Apparatus and
Supplies 2 4-20-83
312.3 Preobservation Operations 2 4-20-83
3.124 On-Site Field Observations 18 4-20-83
3.125 Postobservation Operations 2 4-20-83
3.126 Calculations 7 4-20-83
312.7 Auditing Procedures 2 4-20-83
3.12.8 Reference Method 5 4-20-83
312.9 References and Bibliography 1 4-20-83
312.10 Data Forms 9 4-20-83
-------
April 1983
1
Section 3.12.0
United States
Environmental Protection
Agency
Environmental Monitoring Systems
Laboratory
Research Triangle Park NC 27711
Research and Development
EPA-600/4-77-027b Feb 1984
vvEPA
Section 3.12
Method 9—Visible
Determination of the
Opacity of Emissions from
Stationary Sources
Outline
Section
Summary
Method Highlights
Method Description
1. Certification and Training of
Observers
2. Procurement of Apparatus and
Supplies
3. Preobservation Operations
4 On-Site Field Observations
5 Postobservation Operations
6 Calculations
7 Auditing Procedures
8. Reference Method
9. References and Bibliography
10. Data Forms
Number
Documentation of Pages
3120 2
3120 2
3.12 1
3.12.2
3 12.3
3.12.4
3 12.5
3126
3.12.7
3.12.8
3.12.9
3.12.10
2
2
18
2
7
2
5
1
9
Summary
Many stationary sources discharge
plume-shaped visible emissions into
the atmosphere Method 9 (EPA
Reference Method) is used to
determine the opacity of this plume by
qualified observers. The method
includes procedures for the training
and certification of observers and
procedures to be used by these
observers in the field to determine
plume opacity. This section of the
Quality Assurance (QA) Handbook
primarily concerns procedures used by
the observers Only Section 3.12.1
reviews the training and certification
procedures, which are described in
Reference 1.
The appearance of a plume as
viewed by an observer depends upon
a number of variables, some of which
may be controllable and some of
which may not be controllable in the
field. Variables which can be
controlled to an extent to which they
no longer exert a significant influence
upon plume appearance include.
angle of the observer with respect to
the plume; angle of the observer with
respect to the sun; point of
observation of attached and detached
steam plumes and angle of the
observer with respect to a plume
emitted from a rectangular stack with
a large length to width ratio. The
-------
Section 3.12.0
April 1983
method includes specific criteria
applicable to these variables.
Other variables which may not be
controllable in the field are
luminescence and color contrast
between the plume and the
background against which the plume
is viewed. These variables exert an
influence upon the appearance of a
plume as viewed by an observer, and
can affect the ability of the observer
to accurately assign opacity values to
the observed plume. Research studies
of plume opacity have demonstrated
that a plume is most visible and
presents the greatest apparent opacity
when viewed against a contrasting
background, It follows from this, and
is confirmed by field trials, that the
opacity of a plume, viewed under
conditions where a contrasting
background is present can be
assigned with the greatest degree of
accuracy. However, the potential for a
positive error is also the greatest
when a plume is viewed under such
contrasting conditions. Under
conditions presenting a less
contrasting background, the apparent
opacity of a plume is less and
approaches zero as the color and
luminescence contrast decrease
toward zero. As a result, significant
negative bias and negative errors can
be made when a plume is viewed
under less contrasting conditions. A
negative bias decreases rather than
increases the possibility that a plant
operator will be cited for a violation of
opacity standards due to observer
error.
Method 9 is applicable for the
determination of the opacity of
emissions from stationary sources
pursuant to 60.11(b). Studies have
been undertaken to determine the
magnitude of positive errors that
qualified observers can make while
reading plumes under contrasting
conditions and using the procedures
specified in Method 9. The results of
these studies, which involve a total of
769 sets of 25 readings each, are as
follows:
1. In the case of black plumes, 100
percent of the sets were read
with positive error of less than
7.5 percent opacity; 99 percent
were read with a positive error of
less than 5 percent opacity.
2. In th&case of white plumes, 99
percent of the sets were read
with a positive error (higher
values) of less than 7.5 percent
opacity; 95 percent were read
with a positive error of less than
5 percent opacity.
The positive observational error
associated with an average of twenty-
five readings is therefore established.
The accuracy of the method must be
taken into account when determining
possible violations of applicable
opacity standards.
Note: Proper application of Method
9 by control agency personnel in
determining the compliance status of
sources subject to opacity standards
often involves a number of
administrative and technical
procedural steps not specifically
addressed in the Federal Register
method. Experience has shown these
steps are necessary to lay a proper
foundation for any subsequent
enforcement action. To clearly
delineate items that are EPA
procedural policy and requirements of
the Method 9 from additional quality
assurance procedures, a wording
scheme was developed. All of
Sections 3.12.1, 3.12.2,3.123,
3.12 6, and 3 12.7 are suggested
quality assurance procedures except
where noted as EPA policy or Federal
Register citings. Section 3.12.4 notes
EPA requirements with directive
statements using words such as shall,
should, and must. QA procedures are
noted either with suggestive
statements using words such as
recommended, suggested, and
beneficial or by stating that the entire
subsection is recommended. The use
of these QA procedures should
provide a more consistent program,
improved observer effectiveness and
efficiency, and improved data
documentation.
Method Highlights
Section 3.12 primarily describes
Method 9 procedures for the
determination of plume opacity.
Section 3.12.1 briefly reviews the
quality assurance procedures to be
used in the observer training and
certification procedures described in
detail in Reference 1. The remaining
sections describe the field procedures.
Section 3.12.10 provides blank data
forms recommended for use by the
observer and other personnel, as
required. Partially completed forms,
are included in Sections 3.12.1
through 3.12.7 of the Method
Description. Each form in Section
3.12.10 has a subtitle (e.g., Method 9,
Figure 2.1) to allow easy reference to
the corresponding completed form.
The following paragraphs present a
brief discussion of the contents of this
section of the QA Handbook.
1. Certification and Training of
Observers The primary purpose of this
section is to provide a brief summary
of the certification and training
procedures described in Reference 1.
It includes a definition and a brief
history of opacity, and it discusses
observer training procedures and
certification and recertification of
observers.
2. Procurement of Apparatus and
Supplies Section 3.12.2 presents
specifications criteria and design
features to aid the procurement of
useful equipment that would provide
good quality visible emissions data.
The following are some recommended
equipment items not specifically
required by Method 9: watch,
compass, range finder, Abney level or
clinometer, sling psychrometer,
binoculars, camera, safety equipment,
clipboard, and accessories. Table 2.1
summarizes the quality assurance
aspects of equipment procurement.
3. Preobservation Operations
Section 3.12.3 summarizes the
preobservation activities: gathering
facility information, providing prior
notification, establishing protocol, and
performing equipment checks. Table
3.1 summarizes these procedures.
4. On-Site Field Observations
Section 3.12.4 contains detailed
procedures for determining the visible
emissions (VE). This section not only
includes the recommended
procedures for performing the
perimeter survey, plant entry, and VE
determination; it also contains a
subsection on special observation
problems. This subsection explains
how to take VE readings under less
than ideal conditions (e.g., when the
observer position is restricted). The
main feature of this section is the
presentation of detailed instructions
on how to complete the recommended
VE data form, and examples of
completed forms.
5. Postobservation Operations
Section 3'12.5 presents a brief
discussion concerning the data
reporting procedures, data summary,
data validation, and equipment check.
Section 3.12.6 contains a discussion
of the calculations required for
completing the data forms and
reports. It also includes procedures for
calculating the path length through
the plume and for predicting steam
plume formation by use of a
psychrometric chart and pertinent
measurements.
6. Auditing Procedures Section
3.12.7 recommends performance and
system audits for use with field VE
determinations. The two performance
-------
April 1983 3 Section 3.12.0
audits are an audit by senior
observer/supervisor and a data
calculation audit. A system audit is
suggested, along with a Method 9
checklist, as shown in Figure 7 1.
Table 7.1 summarizes the quality
assurance activities for audits.
7. References and Bibliography
Sections 3.12.8 and 3 12.9 contain
the Method 9 and suggested
references and bibliography.
8. Data Forms Section 3.12.10
provides blank data forms which can
be taken from the QA Handbook for
field use or serve as the basis of a
revised form to be used by the
Agency. Partially completed forms are
included in the corresponding section
of the QA Handbook
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April 1983
Section 3.12.1
1.0 Certification and Training of Observers
The purpose of this section is to
summarize the content of the QA
manual for VE training programs.'
Since the observer must be properly
certified or a qualified VE reader in
order to have his/her opacity reading
accepted, it is important that he/she
fully understand this phase of his/her
training
1.1 Definition and Brief
History of Opacity
The VE evaluation system evolved
from the concept developed by
Maximillian Ringelmann in the late
1800's, in which a chart with
calibrated black grids on a white
background was used to measure
black smoke emissions from coal-fired
boilers. The Ringelmann Chart was
adopted by the U S. Bureau of Mines
in the early 1900's and was used
extensively in efforts to assess and
control emissions In the early 1950's,
the Ringelmann concept was
expanded to other colors of smoke by
the introduction of the concept of
"equivalent opacity."
The Federal government has
discontinued the use of Ringelmann
numbers in EPA Method 9 procedures
for New Source Performance
Standards (NSPS). Current procedures
are based solely on opacity Although
some State regulations still specify
the use of the Ringelmann Chart to
evaluate black and gray plumes, the
general trend is toward reading all
emissions in percent opacity
In practice, the evaluation of opacity
by the human eye is a complex
phenomenon and is not completely
understood However, it is well
documented that visible emissions
can be assessed accurately and with
good reproducibrlity by properly
trained/certified observers
The relationships between light
transmittance, plume opacity,
Ringlemann number, and optical
density are presented in Table 1 1 A
literal definition of plume opacity is
the degree to which the transmission
of light is reduced or the degree to
which visibility of a background as
viewed through the diameter of a
plume is reduced. In terms of physical
optics, opacity is dependent upon
transmittance (I/I0) through the
plume, where I0 is the incident light
flux and I is the light flux leaving the
plume along the same light path.
Percent opacity is defined as follows:
Percent opacity = (1-I/I0) x 100.
Many factors influence plume
opacity readings: particle density,
particle refractive index, particle size
distribution, particle color, plume
background, path length, distance and
relative elevation to stack exit, sun
angle, and lighting conditions. Particle
size is particularly significant;
particles decrease light transmission
by both scattering and direct
absorption. Thus, particles with
diameters approximately equal to the
wavelength of visible light (0.4 to 0.7
fjm) have the greatest scattering effect
and cause the highest opacity.
1.2 Training of Observer
Field inspectors and observers are
required to maintain their opacity
evaluation skills by periodically
participating in a rigorous VE
certification program. Accordingly,
EPA's Stationary Source Compliance
Division (SSCD) and Environmental
Monitoring Systems Laboratory
(EMSL) have provided the QA training
document1 to individuals who conduct
VE training and certification programs.
This section summarizes the training
program
1.2.1 Frequency of Training Sessions
— Certification schools should be
scheduled at least twice per year
since Method 9 requires a semiannual
recertification. It is highly
recommended that training be an
Table 1.1. Comparison of Light, Extinction Terms
Light
transmission, %
0
20
40
60
80
100
Optical density
units
N/A*
0.70
040
0.22
0.10
000
Plume
opacity, %
100
80
60
40
20
O
Ringelmann
number
5
4
3
2
1
0
BN/A - not applicable.
integral part of the certification
program. A spring/fall schedule is
preferable because of weather
considerations. Certifying previous
graduates while the smoke school is
in session is more efficient and less
costly than scheduling a separate
session.
1.2.2 Classroom Training — The
training is accomplished most
effectively by holding an intensive 1 -
or 2-day classroom lecture/discussion
session Although this training is not
required, it is highly recommended for
the following reasons:
1 Increases the VE observer's
knowledge and confidence for the
day-to-day field practice and
application
2. Reduces training time required
to achieve certification.
3. Trains the smoke reader in the
proper recording and
presentation of data that will
withstand the rigors of litigation
and strengthens an agency's
compliance and enforcement
program.
4. Provides a forum for the periodic
exchange of technical ideas and
information
Some states require classroom
training for initial certification only. It
is recommended, however, that
observers attend the classroom
training at 3-year intervals to review
proper field observation,techniques
and method changes and to
participate in the exchange of ideas
and new information.
1.2.3 Lecture Material— Example
lecture material for a thorough
training program is presented in
Section 3 1 and Appendix A of
Reference 1 A typical six-lecture
classroom training program consists
of the following1
Lecture 1—Background, principles,
and theory of opacity.
Lecture 2—Sources of VE's,
presented by someone
thoroughly familiar with
source conditions,
related particle
characteristics, and
opacity reading
procedures and
problems
Lecture 3—Proper procedures for
conducting field
observations under a
variety of conditions
-------
Section 3.12.1
April 1983
Lecture 4—Influence and impact of
meteorology on plume
behavior
Lecture 5—Legal aspects of VE and
opacity measurements
Lecture 6—Actual
observation/testing
procedures
1.2.4 Training Equipment — An
integral part of the training program is
the design and operation of the smoke
generator and its associated
transmissometer, as specified in
Method 9 (reproduced in Section
3128) Such a program is essential
because proper observer certification
cannot take place without the proper
equipment Section 4 of Reference 1
presents performance specifications
and operating procedures for smoke
generators which, if followed under a
good QA program, will ensure
nationwide uniformity and consistency
with Method 9 criteria
The design and operation of the
smoke generator has evolved
significantly since the mid-1960's
The basic components of the smoke
generator now include:
1. Black and white smoke
generating units,
2 Fan and stack,
3 Transmissometer system, and
4 Control panel and strip chart
recorder
Table 1 2 lists the design and
performance specifications for the
smoke generator It must generate
smoke with an opacity range of 0 to
100 percent and be sufficiently
accurate to allow the operator to
control and stabilize the opacity of the
smoke It is recommended that the
generator also achieve and hold
opacities in 5 percent increments at
±2 percent for a minimum of 5 s
White smoke is produced by
dispensing, at regulated rates, No 2
fuel oil into the propane-heated
vaporization chamber The opacity
varies in proportion to the volume of
fuel oil vaporized and is regulated by
adjusting the flow of fuel oil
Black smoke is produced by the
incomplete combustion of toluene in
the double-wall combustion chamber
The toluene flowrate is also controlled
by valves and flowmeters
1.2.5 Equipment Calibration
Procedures — Detailed calibration
procedures are included in a QA
procedures manual for VE training
programs ' The generator transmisso-
meters must be calibrated every six
months or after each repair The
National Bureau of Standards (NBS)
traceable standards (optical filters) for
linearity response are available from
Quality Assurance Division,
Environmental Monitoring Systems
Laboratory, U S EPA, Research
Triangle Park, North Carolina 27711
It is strongly recommended that the
calibration be performed before and
after each certification course to
ascertain whether any significant drift
or deviation has occurred during the
training period The "zero and span"
check must be repeated before and
after each test run. If the drift exceeds
1 percent opacity after a typical 30-
mm test run, the instrument must be
corrected to 0 and 100 percent of
scale before resuming the testing
All of the smoke generator
performance verification procedures
(e g., repair and maintenance work,
spectral response checks, calibration
check, and response time checks)
should be documented in writing and
dated, a bound logbook is highly
recommended These records become
part of the permanent files on the VE
training program
7.2.6 Setup, Operating, and
Shutdown Procedures — Detailed
procedures and a parts list are given
in Section 4 4 of Reference 1.
1.2.7 Storage and Maintenance of
the Smoke Generator — Proper
storage arid maintenance procedures
are essential for smoke generators to
increase their useful operating life
and to provide reliability
7.2.8 Common Problems, Hazards,
and Corrective Actions — The
generator has hot surfaces that can
cause serious burns It is
Table 1.2. Smoke Generator Design and Performance Specifications
Parameter Performance
Light source
Photocell spectral response
Angle of view
Angle of projection
Calibration error
Zero and span drift
Response time ^_
Incandescent lamp operated at ±5% of
nominal rated voltage
Photopic (daylight spectral response
of the human eye)
15° maximum total angle
15° max/mum total angle
±3% opacity, maximum
± 1 % opacity, 30 min
5 s, maximum
recommended that attendees be
advised to stay away from the
generator during training and test
runs It is also recommended that gas
and fuel lines be correctly checked for
leaks prior to each use of the
generator to prevent fire and explosive
hazards to the operator and nearby
attendees
Occasional breakdowns or
malfunctions of the generator usually
occur at the most inopportune times
The problem must be diagnosed and
repairs made expeditiously to provide
the proper training and maintain the
interest of the course attendees
Some common malfunctions are listed
in Section 4 of the QA training
manual.'
1.3 Certification of Observer
This section summarizes the
certification part of the training
program. The first part of the
certification program is to acclimate
the smoke readers The following
procedure is recommended. Both
black and white plumes are produced
at certain levels, and during this
production, the opacity values are
announced. After some standards
exposure, four plumes are presented
to the trainee for evaluation. The
correct values of the four plumes are
announced to provide the trainee with
immediate feedback The majority of
the trainees should be ready to take
the test after a few sets. Certification
runs are made in blocks of 50
readings (25 black smoke and 25
white smoke) The trainees who
successfully meet the criteria receive
a letter of certification and a copy of
their qualification form. The school
retains the original of the qualification
form for a minimum of three years, to
be available for any legal proceedings
that might occur According to Method
9, certification is valid for a period of
only six months Neither certification
or recertification procedures require
the observer to attend the lecture
program; however, it is recommended
that the observer attend the series
during initial certification and
thereafter every three years It is also
recommended that all persons unable
to pass after 10 qualification runs, be
provided additional training before
allowing qualification runs to be
made
Test forms vary greatly because of
the specific needs and experiences of
each agency. Figure 1.1 illustrates
one suggested form The form should
be printed on two-copy paper, the
original for the official file and the
carbon copy for the trainee to grade
after each certification run. The test
-------
April 1983
Section 3.12 1
Aff,i,at,nn
Course location
Date V-/S-B3.
_ Name
Run Number
Sunglasses
Sky
Wind 5i_rf.-
Distance and direction to stack
FT, A/A/£
Reading
number
1
2
3
4
S
6
7
8
9
W
11
r2
13
14
15
16
17
18
19
20
21
22
23
24
25
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
10
10
10
W
W
10
10
10
10
10
W
10
10
10
10
10
10
10
10
10
W
10
10
10
10
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
15
20
20
20
(2^
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
(%&
25
25
25
25
25
25
25
25
25
25
25
25
25
25
25
25
25
25
25
25
25
25
25
25
30
Qg)
30
30
-------
April 1983
Section 3.12.1
form must be filled in completely.
Certification requires that both of the
following criteria be satisfied:
1 No reading may be in error by
more than 15 percent opacity.
2. The average [absolute] error
must not exceed 7.5 percent for
either set of 25 white or 25 black
smoke readings. The certification
runs may be repeated as often as
necessary. However, it is recom-
mended that all persons who
have not passed after ten certi-
fication runs be given addi-
tional training prior to conducting
additional certification runs.
The detailed testing and grading
procedures required to ensure a valid
test are outlined in Section 5 of the
QA training manual.1 The Agency
should maintain a bound logbook,
arranged by training session, for at
least three years, as evidence that the
observer has been certified as a
qualified VE evaluator by a recognized
smoke training and certification group.
Each trainee who successfully meets
the Method 9 criteria receives a letter
of certification and a copy of his/her
qualification form This letter includes
the date of expiration
2. The difference of the average
value between observers should
not exceed 10 percent.
1.6 Smoke School
Certification Quality
Assurance Program
It is recommended that any
government agency planning to
develop a smoke school certification
program obtain a copy of the
"Recommended Quality Assurance
Techniques and Procedures for Visible
Emission Training Programs "' Table
1 3 contains an activity matrix for
certification and training of observers.
1.4 Recertification
Method 9 requires an individual to
be recertified every six months.
1.5 In-the-Field Training
After the observer's initial
certification, it is recommended that a
senior observer accompany the new
observer on a field observation trip
and that both individuals
simultaneously record (using the
same time piece) their opacity
readings as a QA check (see Section
3 12.7). A comparison of these
readings will indicate any problems
the new observer might have in
conducting observations under field
conditions A significant discrepancy
between the readings of the two
observers, m individual or average
values, indicates the need for further
in-field training and continuance of
the senior observer (not necessarily
the same one) QA check After
satisfactory checks have been made
on two consecutive field observations,
the new observer can confidently
conduct inspections without a senior
observer. The suggested standard for
a satisfactory check for 6-min
(minimum) of consecutive readings is:
1. No difference m individual
readings should exceed 20
percent
-------
Section 3.12.1
April 1983
Table 1.3. Activity
Activity
Classroom
training of
observer
Smoke generator
Setup, operating.
and shutdown
procedures
Storage and
maintenance
Transmissometer
Design and perfor-
mance specifications
Calibration
Zero and span
Certification of
observer
Recertification
In -the- field training
Matrix for Certification and Training of Observers
Frequency and Action if
Acceptance method of requirements
limits measurement are not met
Classroom train-
ing per Ref. 1
(suggested)
Should be able
to generate
smoke with an
opacity range of
0 to 100%; hold
opacities ±2%
for at least 5 s
Adherence to
procedures in
Ref, 1
As above
Specifications in
Table 1.2
±3% opacity
maximum
Opacity drift
<1% after a
typical 30 -mm
test run
No reading must
be in error by
more than 15%
and average
absolute error
must not exceed
7 5% for either
white or black
smoke readings
As above
No reading in
error by more
than 20% differ-
ence and
average absolute
error should
not exceed
10% difference
during the field
observation
Initially and
every 3 years
Before each
certification test
run; use method
in Ref 1
Each test run
As above
Upon receipt.
repair, and at
6 -mo intervals
use method in
Ref 1
Every 6 mo or
after repair.
before and after
each certifica-
tion course is
recommended;
use method in
Ref 1
As above
Take smoke
reading test until
a successful test
has been com-
pleted
Every 6 mo take
a smoke reading
test until a
successful test
has been
completed
Checks are made
on the first two
field observa-
tions subse-
quent to the
initial certifica-
tion; comparison
is made between
new certified
observer and an
experienced
observer
Review training
procedures per
Ref. 1
Adjust and make
repeat check of
operation
Review pro-
cedures
As above
Adjust and
repeat specifica-
tion check until
specifications
are met
Adjust and
recalibrate until
acceptance
limits are met
Instruments
must be cor-
rected to O and
100% before
testing is
resumed
Retake test until
successful com-
pletion
As above
Continue com-
parisons until
acceptance
limits are met
during two field
observations
-------
April 1983
Section 3.12.2
2.0 Procurement of Apparatus and Supplies
Method 9 does not specifically
require any equipment or supplies
Therefore, this entire section includes
quality assurance procedures that are
recommended to assist the observer
in documenting data Nevertheless,
this section provides specifications
criteria or design features, as
applicable, to aid in the selection of
equipment that may be useful in
collecting VE data Procedures and
limits for acceptance checks are also
provided During the procurement of
equipment and supplies, it is
suggested that a procurement log
(Figure 2 1) be used to record the
descriptive title of the equipment, the
identification number (if applicable),
and results of any acceptance checks
Table 2 1 at the end of this section
contains a summary of the quality
assurance activities for procurement
and acceptance of apparatus and
supplies
2.1 Stopwatch
A watch is used to time the 1 5-
second intervals between opacity
readings The watch should provide a
continuous display of time to the
nearest second
2.2 Compass
A compass is useful for determining
the direction of the emission point
from the spot where the VE observer
stands and for determining the wind
direction at the source For accurate
readings, the compass should be
magnetic with resolution better than
10° It is suggested that the compass
be jewel-mounted and liquid-filled to
dampen the needle swing; map
reading compasses are excellent for
this purpose
2.3 Range Finder
A range finder is used to measure
the observer's distance from the
emission point and should be capable
of determining distances to 1000
meters with an accuracy of ±10
percent The accuracy of the range
finder should be checked upon receipt
and periodically thereafter with
targets at known distances of
approximately 500 meters and 1000
meters
Item description
^op^vfck
Quantity
z
Purchase
order
number
5L50?6
Vendor
F/sher
Scientific
Date
Ordered
S/t/VL
Received
5//y/s*
Cost
*52ft
Disposition
checked.-
ready
Comments
Figure 2.1. Example of a procurement log
-------
Section 3.12.2
April 1983
2.4 Abney Level or
Clineometer
An Abney level is a device for
determining the vertical viewing angle
For visible emission observation
purposes, it should measure within 5
degrees. The accuracy should be
tested by placing the level flat on a
table that has been previously leveled
with a referring level and checking it
at a 45° angle by placing it on a 45°
inclined plane constructed with the
plane as the hypotenuse of a right
triangle with equal base and height
2.5 Sling Psychrometer
The sling psychrometer is used m
cases where it is suspected that the
atmospheric conditions will promote
the formation of a steam plume (see
Subsection 6 3) The psychrometer
should consist of two thermometers,
accurate to 1/2°C, mounted on a
sturdy assembly whereby the
thermometers may be swung rapidly
in the air. One thermometer should be
fitted with a wettable cotton wick tube
on the bulb Thermometer accuracy
should be checked by placing the
bulbs in a fresh ice water bath at 0°C
2.6 Binoculars
It is recommended that the observer
obtain binoculars preferably with a
magnification of at least 8 x 50 or 10
x 50 The binoculars should have
color-corrected coated lenses and a
rectilinear field of view. Color
correction can be checked by viewing
a black and white pattern such as a
Ringelmann card at a distance greater
than 50 ft, no color rings or bands
should be evident, only black and
white The rectilinear field of view can
be tested by viewing a brick wall at a
distance greater than 50 ft There
should be no distortion of the brick
pattern as the field of view is
changed. The binoculars are helpful
for identifying stacks, searching the
area for emissions and aid in
characterizing behavior and
composition of plume
2.7 Camera and Accessories
A camera is often used in VE
observations to document the
emissions before and after the actual
opacity determination A 35-mm
camera with through-the-lens light
metering is recommended for this
purpose Useful accessories include a
"macro" lens or a 250-mm to 350-
mm telephoto lens, and a 6-diopter
closeup lens (for photographing
logbook and evidence of particulate
deposition) A photo logbook is
necessary for proper documentation,
and the observer should always be
sure to purchase enough fresh color
negative film (ASA 100
recommended) for his/her purposes
2.8 Clipboard and
Accessories
For documenting the visible
emission observation, the observer
should have a 10 in x 12 in masonite
or metal clipboard, several black ball-
point pens (medium point), a large
rubber band, and a sufficient number
of visible emission observation forms
2.9 Safety Equipment
The following safety equipment,
which should be approved by the
Occupational Safety and Health
Association (OSHA), is recommended
for the VE observer:
• Hard hat m high-visibility yellow
or orange
• Safety glasses, goggles, or eye
shields
• Ear protectors
• Safety shoes (steel-toed for
general industrial use)
Specially insulated safety shoes are
necessary in certain areas, such as
the top of coke ovens
Table 2.1. Activity Matrix, for Procurement of Recommended Equipment and
Supplies
Equipment
Watch
Compass
Range finder
Abney level
Sling psychrometer
Binoculars
Camera
Clipboard/
accessories/forms
Safety equipment
Acceptance limns
Continuous
display
Magnetic with
10° resolution
Accuracy of
±10% over dis-
tances to 1000m
Accurate within
+5°
Each thermom-
eter accurate
to 1/2°C (1°F)
Magnification of
8x50or 10x50.
color-corrected
coated lenses
and a rectilinear
field of view
35-mm camera
with through-
the-lens light
metering
W in. by 12 m
clipboard; black
ball-point pens.
VE observation
forms
Hardhat — yellow
or orange, safety
glasses and
shoes, ear
protectors
Frequency and
method of
measurement
Check upon
receipt
Check upon
receipt
Check upon
receipt and
quarterly with
targets at known
distances of
about 500 m and
1000 m
Check at 0° and
45°
Check thermom-
eter accuracy
with ice water
bath at 0°C
Check upon
receipt by view-
ing selected
objects
Check quality of
photos on
receipt and after
processing film
Check supplies
periodically
Check supply of
safety equip-
ment periodi-
cally
Action if
requirements
are not met
Return to
supplier
Return to
supplier
Adjust or
return to
supplier
Same as above
Repair or return
to supplier
Return to
supplier
Return to
supplier for
repair
Replenish
supplies
Maintain equip-
ment availability
-------
April 1983
Section 3.12.3
3.0 Preobservation Operations
The following procedures are not
required by Method 9 but are
recommended in order to provide
more consistent data collection and
better data documentation and
verification of representative plume
viewing conditions Not all procedures
are needed for every observation
Before making on-site VE
determinations, the observer should
gather the necessary facility data,
provide prior notifications when
applicable, establish an observation
protocol, and check for availability of
supplies and properly maintained
equipment. Table 3.1 at the end of
this section summarizes the quality
assurance activities for preobservation
operations
3.1 Gather Facility
Information
The observer should be thoroughly
familiar with the source facility,
operation, emissions, and applicable
regulations In preparation for the on-
site visit, the observer should review
the Agency's information (m the official
source file) on the source in question.
The observer should:
1. Determine the pertinent people
to be contacted
2 Become familiar with the
processes and operations at the
facility and identify those
facilities to be observed.
3. Review the permit conditions,
requirements, and recent
applications
4 Determine applicable emission
regulations
5 Identify all operating air
pollution control equipment,
emission points, and types and
quantities of emissions
6 Review history of previous
inspections, source test results,
and complaints
7 Check the file to become
familiar with (or review) plant
layout and possible observation
sites
8. Determine normal production
and operation rates.
9. Identify unique problems and
conditions that may be
encountered (e.g., steam
plume)
10. Discuss with attorney if case
development is expected
11 Obtain a copy of the facility
map with labeled emission
points, profile drawings, and
photographs, if available. A
facility map is very helpful
during inspection and should be
a required item for every
Agency source file The map
makes it easier for the observer
to identify point sources and
activities, and it may be used to
mark any emission points that
have been added or modified.
12 If an operating permit exists,
obtain a copy because it may
contain the VE limits for each
point source and any special
operating requirements.
13. Determine the status of the
source with respect to any
variance or exemption from the
Agency's rules and regulations
Observation may not be required if
the source has a variance or is
exempt from the regulations.
14 Review plant terminology
15. Use references such as facility
maps and previous inspection
reports to determine if the
viewing position is restricted
because of buildings or natural
barriers If the viewing position
requires observations to be
taken at a particular time of day
(morning or evening) because
of sun angle, consider this
when planning the inspection.
16. Determine the possibility of
water vapor in the plume
condensing (see Section
3.12.6). This determination may
prevent a wasted trip to the
facility on days when a
persistent water droplet plume
is anticipated because of
adverse ambient conditions.
Note. If the observer is not familiar
with the type of facility or operation,
he/she should consult available
reference material and inspection
manuals on the source category
3.2 Prior Notification
The-usual procedure is to make the
VE determination without prior
notification unless the plant must be
entered first to obtain a good view of
the emission point of interest
However, this procedure is not always
possible, especially m remote
locations, when operations are
intermittent, or when specific
personnel must be present or
contacted Determining VE for
compliance with State Implementation
Plan (SIP) or NSPS opacity regulations
requires on-site observations during
conditions of typical or normal
maximum operations If the facility is
notified of the time of this evaluation,
some operating conditions may be
altered. If this situation appears likely,
it is EPA's policy not to give prior
notification EPA is obligated to notify
State/local agencies of inspections
and generally prefers to invite the
applicable agency to participate. The
observer should notify the affected
facility and control agencies as soon
as practical following any official
opacity readings.
3.3 Establish Observation
Protocol
Based on information collected
under Section 3.1 and any prior
experience with the source, an
observation protocol should be
established. First, the observer
should determine whether one, two,
or more observers will be required.
For example, two observers may be
required to simultaneously make the
VE determination and gather other
on-site data (e.g , take photographs,
draw a new modified facility map if
one is not available from the plant or
gather other needed plant information).
In certain situations where the VE
observations must be correlated to
process operation, the second person
will closely monitor the process
activity and record the exact time of
the operating modes of interest Only
one observer will make the VE
determination unless an observer
audit is being conducted. In this case,
the designated observer is the one
being audited.
The applicability of Method 9 (and
hence the method of observation)
should be determined. If Method 9 is
not applicable, see Section 3124,
Special Problems.
A written checklist regarding an
expected walk-through of the plant
including questions to ask plant
officials may be helpful
3.4 Perform Equipment
Checks for On-Site Use
Be sure that the necessary
equipment and supplies are available
for making the VE determination and
documenting the results All
equipment should be visually checked
for damage and satisfactory operation
before each VE determination field
trip.
-------
Section 3.12.3
April 1983
Table 3.1. Activity
Activity
Gather facility
information
Make prior
notification
Establish protocol
Perform equipment
check
Matrix for Preobservation Operations
Frequency and
Acceptance method of
limits measurement
Obtain neces-
sary facility data.
Subsec 3 1
Make VE deter-
mination with-
out prior notifi-
cation except as
stated in Subsec
3 2; EPA should
notify State/
local agencies
and invite
participation
Prepare obser-
vation protocol.
Subsec 3.3
All equipment/
supplies avail-
able and in sat-
isfactory work-
ing order
Check for com-
pleteness of data
Check the pro-
tocol for notifi-
cation before
each on -site visit
and revise the
protocol as
necessary
Check before
on-s/te visit
Same as above
Action if
requirements
are not met
Obtain missing
data before on-
s/te visit, if
possible
Make required
notifications
Complete or
prepare protocol
as required
Rep/ace or
adjust
equipment
-------
April 1983
Section 3.12.4
4.0 On-Site Field Observations
This section describes field
observation procedures, including
perimeter survey, plant entry, VE
determination, and special observation
problems. The latter subsection
supplements the subsection on VE
determination by providing some
information on how to take VE
readings when unfavorable field
conditions prevent the use of the
procedure described in Subsection 4 3
(e.g., when the emissions are
intermittent or the observer position is
restricted) The QA activities are
summarized in Table 4.2 at the end of
this section.
4.1 Perimeter Survey
Before and after the VE
determination, it is strongly
recommended that the observer make
a perimeter survey of the area
surrounding (1) the point of
observation and (2) the emission point
on which the determination is being
made Such a survey also may be
made during the VE determination, if
warranted
A perimeter survey can be useful
in determining the presence of other
factors that could affect the opacity
readings. For example, the
representativeness of the VE readings
for a given emission point could be
questioned unless data is available to
show that the observer excluded
emissions related to material
stockpiling, open burning, and
ambient condensed water vapor in
adjoining areas of the plant It is vital
that the observer be as aware as
much as possible of extenuating
conditions. The perimeter survey is
made to document these conditions.
Common sense should be used in
determining the need and extent of
the survey; in some cases (e.g , a
single 350-foot stack) a perimeter
survey is not vital.
Perimeter surveys can be made
from either outside or inside the plant
property, or both This decision would
depend on whether the VE
observations are made from inside or
outside of the plant, whether the
observer actually gains entry to the
plant premises, and whether the plant
is sufficiently visible from outside the
premises to make a reasonable
survey. It is suggested that during the
survey the observer should note such
factors as:
1 Other stacks and emission points
whose visible emissions might
interfere with opacity readings
2 Fugitive emissions that result
from product or waste storage
piles and material handling and
may interfere with observations
3. Fugitive emissions that result
from unpaved road travel and
may interfere with observations
4. Water vapor emissions from
sludge or cooling ponds
5. Open burning
6. Any unusual activities on or
around plant premises that could
result in nonrepresentative
emissions or interfere with
opacity readings.
If deemed useful by the observer,
photographs may be taken to
document extenuating conditions (see
discussion of confidentiality and the
use of cameras in Subsection 4 2.7)
4.2 Plant Entry
The following discussion presents
the recommended plant entry
procedures. The VE readings
themselves should not be affected by
a change in these procedures.
However, the usefulness of the
readings in showing a possible
violation of the applicable standards
may be compromised by not following
agency procedures for entering plants
Depending on the location of emission
points at the plant and the availability
of observation points in the area
surrounding a facility, the VE observer
may not have to gam entry to the
plant premises prior to making VE
observations. It may be preferable to
gain access after taking readings to
check on plant process control
equipment operating conditions or to
complete a perimeter survey. Figure
41 is an example entry checklist that
can be used to assist the observer in
organizing the information that could
be used at the time of plant entry
To maintain a good working
relationship with plant officials and,
most importantly, to comply with the
Clean Air Act and avoid any legal
conflict with trespass laws or the
company's right to privacy and due
process of law under the U.S
Constitution, the observer must follow
certain procedures in gaming entry to
the plant's private premises. In most
cases, consent to enter (or the
absence of express denial to enter) is
granted by the owner or company
official Figure 4 1 lists the pertinent
section of the Clean Air Act on facility
entry as well as information on
confidentiality of process information
It is recommended that the inspector
have a copy of this information
available in case questions are raised
by source representatives
4.2.1 Entry Point — It is
recommended that the plant premises
be entered through the mam gate or
through the entrance designated by
the company officials in response to
prior notification. The observer's
arrival will usually occur during
normal working hours unless
conditions contributing to excess
opacity levels are noted at certain
times other than normal working
hours. If only a guard is present at the
entrance, it is desirable for the
observer to present the appropriate
credentials and to suggest that the
guard's supervisor be contacted for
the name of a responsible company
official The observer would then ask
to speak with this official, who may be
the owner, operator, or agent in
charge (including the environmental
engineer)
4.2.2 Credentials — After
courteously introducing
himself/herself to the company
official, the observer should briefly
describe the purpose of the visit and
present the appropriate credentials
confirming that he/she is a lawful
representative of the agency Such
credentials will naturally differ
depending upon the agency
represented, but it is recommended
that they include at least the
observer's photograph, signature,
physical description (age, height,
weight, color of hair and eyes), and
the authority for plant entry Agencies
issue credentials in several forms,
including letters, badges, ID cards, or
folding wallets
4.2.3 Purpose of Visit — When first
meeting with a company official, the
observer needs to be prepared to state
succinctly the purpose of the visit,
including the reason for the VE
determination Space is provided in
the recommended form (Figure 4 1) to
specify the exact purpose of the visit,
and the observer can refer to this
when talking with the company
official
-------
Section 3.12.4
April 1983
Source name and address
5MTE"
/V.7
Observer JuDY A,
Agency u 5
of l/£ observation
Previous company contact fit applicable)
C-
Purpose of visit £/>/( Aub&
/A/ AIJ zvzfiy
Emission points at which VE observations to be conducted
01 (jft/V£&Z. 3'0>5"0c.7--oz
-------
April 1983
Section 3.12.4
Authority for Plant Entry Clean Air Act. Section 114
la)(2) the Administrator or his authorized representative upon presentation of his credentials -
(A) shall have a right of entry to, upon or through any premises of such person or in which any records required to be
maintained under paragraph (1) of th/s section are located, and
(B) may at reasonable times have access to, and copy of any records, inspect any monitoring equipment or methods
required under paragraph (1), and sample any emissions which such person is required to sample under
paragraph (1)
(b) (1) Each State may develop and submit to the Administrator a procedure for carrying out this section in such State If the
Administrator finds the State procedure is adequate, he may delegate to such State any authority he has to carry out this
section.
(2) Nothing in this subsection shall prohibit the Administrator from carrying out this section in a State
(cjAny records, reports or information obtained under subsection /a) shall be available to the public except that upon a showing
satisfactory to the Administrator by any person that records, reports, or information, or particular part thereof, (other than
emission data) to which the Administrator has access under this section if made public would divulge methods or processes
entitled to protection as trade secrets of such person, the Administrator shall consider such record, report, or information or
particular port/on thereof confidential in accordance with the purposes of Section 1905 of Title 18 of the United States
concerned with carrying out this Act or when relevant in any proceeding under this Act."
Confidential Information' Clean Air Act, Section 114 (see above) 41 Federal Register 36902, September 1, 1976
If you believe that any of the information required to be submitted pursuant to this request is entitled to be treated as
confidential, you may assert a claim of business confidentiality, covering all or any part of the information, by placing on (or
attaching to) the information a cover sheet, stamped or typed legend, or other suitable notice, employing language such as
"trade secret," "proprietary," or "company confident/a/." Allegedly confidential portions of otherwise nonconfidential
information should be clearly identified. If you desire confidential treatment only until the occurrence of a certain event, the
notice should so state Information so covered by a claim will be disclosed by EPA only to the extent, andthrough the procedures,
set forth at 4O CFR, Part 2, Subpart B (41 Federal Register 36902, September 1, 1976 )
If no confidentiality claim accompanies this information when it is received by EPA, it may be made available to the public by
EPA without further notice to you
Figure 4.1. Reverse side of form. (Continued)
The principal purpose for an
observer's visit to a plant will probably
fall into one of three categories (1) a
VE determination is being made
pursuant to a neutral administrative
scheme* to verify compliance with an
applicable SIP or NSPS, (2) a VE
determination is being made because
some evidence of an opacity violation
already exists, or (3) an unscheduled
VE determination has just been made
from an area off the plant property
The statement of purpose should state
clearly what has prompted the visit
At this time, the observer also
should provide the company official
with a copy of the opacity readings
and ask that person to sign an
acknowledgment of receipt of any VE
readings made previous to entry In
lieu of the above, the agency should
provide a copy within a reasonable
time
4.2.4 Visitor's Agreements, Release
of Liability (Waivers) — The observer
should not sign a visitor's agreement,
release of liability (waiver), hold-
harmless agreement, or any other
agreement that purports to release
•Any routine of selecting sites for observation
that is not directed toward any company
the company from tort liability.
Signing this type of release form may
waive the rights of the observer and
his/her employer compensation in
event of personal injury or damages;
the precise effect of signing an
advance release of liability for
negligence depends upon the laws of
the state in which it is signed. If the
plant official denies entry for refusal
to sign a release form, the observer
should proceed as described in the
section on entry refusal
4.2.5 Section 114 — Section 114 of
the Clean Air Act addresses both the
authority for plant entry and the
protection of trade secrets and
confidential information For the
observer's reference, the applicable
paragraphs are included on the
reverse side of the entry checklist in
Figure 4 1
4.2.6 Entry Refusal — In the event
that an observer is refused entry by a
plant official or that consent is
withdrawn before the agreed-upon
activities have been completed, the
following procedural steps should be
followed
1 Tactfully discuss the reason(s) for
denial with the plant official; this
is to insure that the denial
has not been based on some sort
of misunderstanding. Discussion
might lead to resolution of the
problem and the observer may be
given consent to enter the
premises. If resolution is beyond
his/her authority, the observer
should withdraw from the
premises and contact his/her
supervisor to decide on a
subsequent course of action
2 Note the facility name and exact
address, the name and title of
the plant officials approached,
the authority of the person
issuing the denial, the date and
time of denial, the reason for
denial, the appearance of the
facility, and any reasonable
suspicions as to why entry was
refused
3 The observer should be very
careful to avoid any situations
that might be construed as
threatening or inflammatory
Under no circumstances should
the potential penalties of entry
denial be cited.
All evidence obtained prior to the
withdrawal of consent is considered
admissible in court.
-------
Section 3 12.4
April 1983
When denied access only to certain
parts of the plant, the observer should
make note of the area(s) and the
official's reason for denial After
completing normal activities to the
extent possible and leaving the
facility, the observer should contact
his/her supervisor for further
instructions
4.2.7 Confidentiality of Data — In
conducting the VE investigation, the
observer may occasionally obtain
proprietary or confidential business
data It is essential that this
information be handled properly
The subject of confidential business
information known as "a trade secret"
is addressed in Section 114 of the
Clean Air Act (see Subsection 425)
and in the Code of Federal
Regulations (40 CFR 2, 41 Federal
Register 36902, September 1, 1976,
as amended). The Code of Federal
Regulations (40 CFR 2, Subpart B,
2.203) embodies a notice to be
included in EPA information requests
This notice is paraphrased on the
reverse side of the entry checklist
(Figure 4.1) for the observer's and
plant official's reference The Code of
Federal Regulations (40 CFR 2,
Subpart B, 2 211) also includes the
penalties for wrongful disclosure of
confidential information by Federal
employees, m addition to the penalties
set forth in the United States Code,
Title 18, Section 1905 Employees of
other agencies should check with
agency attorneys to determine their
exact personal liability
From the observer's standpoint,
confidential information may be
defined as information received under
a request of confidentiality which may
concern or relate to trade secrets A
trade secret is interpreted as an
unpatented secret, commercially
valuable plan, appliance, formula, or
process used m production This
information can be in written form, in
photographs, or in the observer's
memory Emissions data are not
considered confidential information
Also the Agency reserves the right to
determine if information submitted to
it under an official request should be
treated as confidential
A good rule of thumb for the
observer to follow is to collect only
that process and operational
information and to take only those
photographs that are pertinent to the
purpose of the plant visit. The plant
official should be advised that he
must request confidential treatment of
specific information provided (see
paragraph on claims of confidentiality
on reverse side of entry checklist)
before it will be treated as confidential
pending legal determination The plant
official should inform the observer of
any sensitive areas of the facility or
processes where proprietary or trade
secret information is indicated
Photographs are often used to
document visible emissions
observations (see Subsection 434)
Before taking photographs from inside
the plant premises, the observer must
have the consent of the plant official
Most of an observer's photographs
will be of emission points only;
presumably, these should not include
confidential areas of the plant If any
opposition is encountered regarding
the use of a camera on the plant
premises, the observer should explain
that the plant official should request
confidential treatment of any
photographs taken The observer
must properly document each
photograph and handle those for
which confidential treatment has been
requested in the same manner as
other confidential data Photographic
documentation of VE observations
from an area of public access outside
of the plant premises does not require
approval from a plant official, provided
the documentation is accomplished
without the use ot highly
sophisticated equipment or
techniques For example, use of a
high-power telephoto lens (over 100
mm on a 35 mm camera) that yields
extensive details (e g , construction
layout) might be construed as
surreptitiously taking confidential
business information Thus, a good
rule of thumb is to be sure that any
pictures taken show only the details
that could be seen with the naked eye
from an area accessible to the public
When preparing to leave the plant,
the observer should allow the plant
official to examine the data collected
and make claims of confidentiality All
potentially confidential information
should be so marked, and while on
the road, the observer should keep it
in a locked briefcase or file container
It should be noted that emission data
are not considered confidential
When the observer returns to the
agency office, the potentially
confidential information should be
placed in a secure, lockable file
cabinet designated especially for that
purpose The observer's agency
should have an established secure
filing system and procedures for
safeguarding confidential documents
In all cases, the observer should make
no disclosure of potentially
confidential information until a
company has had full opportunity to
declare its intentions regarding the
information and the Agency has ruled
that the information is not legally
confidential
4.2.8 Determination of Safety
Requirements — The violation of a
safety rule does not invalidate VE
readings, however, the observer
should always anticipate safety
requirements by arriving at the plant
with a hardhat, steel-toed safety
shoes, safety glasses with side
shields, and ear protectors Safety
equipment also should include any
other equipment that is specified m
the agency files and noted on the
entry checklist form.
Some companies require unusual
safety equipment, such as specific
respirators for a particular kind of
toxic gas In many cases, these
companies will provide the observer
with the necessary equipment. In any
event, the observer must be aware of
and adhere to all safety requirements
before entering the plant. Information
on plant alarms and availability of first
aid and medical help may be needed.
4.2.9 Observer Behavior —
Observers must perform their duties
m a professional, businesslike, and
responsible manner They should
always consider the public relations
liaison part of their role by seeking to
develop or improve a good working
relationship with plant officials
through use of diplomacy, tact, and if
necessary, gentle persuasion in all
dealings with plant personnel.
Specifically, observers should be
objective and impartial m conducting
observations and interviews with
plant officials All information
acquired during a plant visit is
intended for official use only and
should never be used for private gain.
Observers must be careful never to
speak of any person, agency, or
facility in any manner that could be
construed as derogatory Lastly,
observers should use discretion when
asked to give a professional opinion
on specific products or projects and
should never make judgments or draw
conclusions concerning a company's
compliance with applicable
regulations Upon giving the data to
the plant the observer can tell the
source these are the data that were
obtained and no judgment as to
compliance can be made until all the
data and the regulations are closely
reviewed
-------
April 1983
Section 3.12 4
4.3 Visible Emission
Determination
This subsection describes the
preferred approach to VE
determination Because practical
considerations do not always permit
the observer to follow this procedure,
however, special observation
problems are discussed in Subsection
4.4.
4.3.1 Opacity Readings — The
observer must be certified in
accordance with Section 3121,
Subsection 1.3, and should use the
following procedure for visually
determining the opacity of emissions
Observer Position
1. The observer must stand at a
distance that provides a clear
view of the emissions with the
sun oriented in the 140° sector
to his/her back If the observer
faces the emission/viewing point
and places the point of a pencil
on the sun location line such
that the shadow crosses the
observers position, the sun
location (pencil) must be within
the 140° sector of the line
During overcast weather
conditions, the position of the
sun is less important
2. Consistent with number 1 above,
when possible, the observer
should, make observations from
a position in which the line of
vision is approximately
perpendicular to the plume
direction, when observing
opacity of emissions from
rectangular outlets (e g , roof
monitors, open baghouses, and
noncircular stacks), the
observer's position should be
approximately perpendicular to
the longer axis of the outlet
3 When multiple stacks are
involved, the observer's line of
sight should not include more
than one plume at a time, and in
any case, during observations,
the observer's line of sight
should be perpendicular to the
longer axis of a set of multiple
stacks (e g , stub stacks on
baghouses)
4 The observer must stand at a
distance that provides total
perspective and a good view
5 In order to comply with the sun
angle requirements (see item 1)
it is recommended that the
observer should try to avoid the
noon hours (11 00 a.m to 1 00
p.m.) in the summertime (when
the sun is almost overhead) This
is more critical in the southern
continental United States The
preferred reading distance is
between 3 stack heights and 1/4
mile from the base of the stack.
6 The reading location should be
safe for the observer
Opacity Observations
1 Opacity observations must be
made at the point of greatest
opacity in that portion of the
plume where condensed water
vapor is not present
2 The observer must not look
continuously at the plume (this
causes eye fatigue), but should
observe the plume momentarily
at 15-s intervals A 15-s beeper
is recommended to aid in
performing the VE readings
3 When steam plumes are
attached, i e , when condensed
water vapor is present within the
plume as it emerges from the
emission outlet, the opacity must
be evaluated beyond the point in
the plume at which condensed
water vapor is no longer visible
The observer must record the
approximate distance from the
emission outlet to the point in
the plume at which the
observations are made
4 When steam plumes ate
detached, i e . when water vapor
in the plume condenses and
becomes visible at a distinct
distance from the emission
outlet, the opacity of emissions
should be evaluated near the
outlet, prior to the condensation
of water vapor and the formation
of the steam plume, unless the
opacity is higher after
dissipation
5 Readings must be made to the
nearest 5 percent opacity A
minimum of 24 observations
must be recorded. It is advisable
to read the plume for a
reasonable period in excess of
the time stipulated in the
regulations (i e , at least 10
readings more than the minimum
required)
6 A clearly visible background of
contrasting color is best for
greatest reading accuracy
However, the probability of
positive error (higher values) is
greater under these conditions
Generally, the apparent plume
opacity diminishes and tends to
assume a negative bias as the
background becomes less
contrasting
7 It is recommended the observer
wear the same corrective lenses
that were worn for certification
If sunglasses were not worn
during certification, the observer
should remove them and allow
time for the eyes to adjust to the
daylight before making VE
determinations It is
recommended that the observer
no! wear photo compensating
sunglasses
8 The best viewing spot is usually
within one stack diameter above
the stack exit, where the plume
is densest and the plume width
is approximately equal to the
stack's diameter
4.32 Field Data The "Visible
Emission Observation Form" -- The
1977 revision of EPA Method 9
specifies the recording of certain
information in the field documentation
of a visible emission observation The
required information includes the
name of the plant, the emission
location, the type of facility, the
observer's name and affiliation, the
date, the time, the estimated distance
to the emission location, the
approximate wind direction, the
estimated windspeed, a description of
the sky conditions (presence and color
of clouds), and the plurne background
Experience gained from past
enforcement litigation involving
opacily readings as primary evidence
of emission standards violations has
demonstrated a need for additional
documentation when making visual
determinations of plume opacity The
Visible Emission Observation Form
presented in Figure 4 2 is
recommended This form was
developed after reviewing the opacity
forms used in EPA Regional Offices
and State and local air quality control
agencies The form includes not only
the data required by Method 9, but
also the information necessary for
maximum legal acceptability Valid
data can be collected on any form,
however, the recommended form may
enhance observer efficiency and data
documentation A detailed description
of the use of the recommended form
is given in the following paragraphs
The Visible Emission Observation
Form can be functionally divided into
11 major sections, as shown in Figure
4 3 Each section documents one or
two aspects of the opacity
determination The form endeavors to
cover all the required and
recommended areas of documentation
in a typical opacity observation A
"comments" section is included for
notation of any relevant information
that is not listed on the form
-------
Section 3.12.4
April 1983
VISIBLE EMISSION OBSERVA TION FORM
SOURCE NAME
ADM//W. POUJEK PLANT
ADDRESS
/«. OCEAN floAD
ctN#\im- cnY s
PHONE
tc^- 42.
S
PROCESS EQUIPMENT
OIL. F/R&& SO/d.€Je.
CONTROL EQUIPMENT
E/_eC77e037/477£ /PtfSW/TTKTO
TATE
VA
ZIP
OURCE ID NUMBER
ve.D5 V-S7X/
OPERATING MODE
OPERA TING MODE
£- fapr
"7/Vt?
DESCRIBE EMISSION pO/NT
START STOP tX'
HEIGHT ABOVE GROUND LEVEL H
START /GO ' STOP .X S
DISTANCE FROM OBSERVER L
START 4&>' STOP ^ S
EIGHT RELATIV
TART /OO '
E TO OBSERVER
STOP */
DIRECTION FROM OBSERVER
TARTfi/A/E- STOP,/
DESCRIBE EMISSIONS
QT/IDT *—&P" Y f^^^J Jr^.Uf~t C- ^Tf~)P /^
EMISSION COLOR P
START / "sTOP (/^ F
WA TER DROPLETS PRESENT II
NO t4 YESD
LUME TYPE CONTINUOUS^
UG/TIVE O INTERMITTENT D
r WA TER DROPLET PLUME
ATT A CHED D DETA CHED D
POINT IN THE PLUME A T WHICH OPACITY WAS DETERMINED
START /o'/m&fcSTJCg £.)(t1~ STOP ^
DESCRIBE BACKGROUND
START ££<{ STOP W/a&JXSe/U Ct-OO&S
BACKGROUND COLOR S
WIND SPEED V\
START /5~ftf>H STOP 2£>HPf( s
AMBIENT TEMP v\
START "SS'/^ STOP
St/n-y- Wind-^. ] V
Plume and ^ [Observers Pos,tion V X
Stack ^-^\/^^^ ffAJte
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V^v
Sun Location Line -\\-
COMMENTS ^
/ HA VE RECEIVED A COPY OF THESE OPACITY OBSERVA TIONS
SIGNATURE 2*/^W^U»- T' QoAvCJ*-
TITLE
^ DATE
OBSERVATION DATE
15 JULY It?}.
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7
2
3
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9
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11
12
13
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15
16
17
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21
22
23
24
25
26
27
28
29
30
0
30
55
35
30
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(,0
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30
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35
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STOP TIME
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NUMBER OF READINGS ABOVE
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CERTIFIED BY .
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-------
April 1983
Section 3.12.4
VISIBLE EMISSION OBSERVA TION FORM
This form is designed to be used in conjunction with EPA Method 9, "Visual Determination of the Opacity of Emissions from Stationary
Sources." Any deviations, unusual conditions, circumstances, difficulties, etc., not dealt with elsewhere on the form should be fully noted
in the section provided for comments. Following are brief descriptions of the type of information that needs to be entered on the form, for a
more detailed discussion of each part of the form, refer to the "User's Guide to the Visible Emission Observation Form
"Source Name - full company name, parent company or division
information, if necessary.
"Sky Conditions - indicate cloud cover by percentage or by
description (clear, scattered, broken, overcast, andcolor of clouds)
* Address - street (not mailing) address or physical location
of facility where VE observation is being made
Phone - self-explanatory
Source ID Number - number from NEDS, CDS, agency file, etc
* Process Equipment, Operating Mode - brief description of process
equipment (include ID no.I and operating rate, % capacity utilization,
and/or mode (e.g, charging, tapping)
"Control Equipment, Operating Mode - specify control device type(s)
and % utilization, control efficiency
* Describe Emission Point - stack or emission point location, geometry,
diameter, color, for identification purposes
*Height Above Ground Level - stack or emission point height, from
files or engineering drawings
* Height Relative to Observer - indicate vertical position of observation
point relative to stack top
* Distance From Observer - distance to stack +10%, to determine, use
rangefinder or map
*Direction From Observer - direction to stack, use compass or map,
be accurate to eight points of compass
"Describe Emissions - include plume behavior and other physical
characteristics (e.g. looping, lacy, condensing, fumigating, secondary
particle formation, distance plume visible, etc 1
'Emission Color - gray, brown, white, red, black, etc
Plume Type:
Continuous - opacity cycle >6 minutes
Fugitive - no specifically designed outlet
Intermittent • opacity cycle <6 minutes
"" Water Droplets Present - determine by observation or use wet sling
psychrometer, water droplet plumes are very white, opaque, and
billowy in appearance, and usually dissipate rapidly.
""If Water Droplet Plume:
Attached - forms prior to exiting stack
Detached - forms after exiting stack
""Point in the Plume at Which Opacity was Determined - describe
physical location in plume where readings were ma'de (e g ,4 in above
stack exit or 10 ft after dissipation of water plume)
"Describe Background - object plume is read against, include
atmospheric conditions (e.g, hazy).
* Background Color - blue, white, new leaf green, etc
'Required by Reference Method 9, other items
suggested
"'Required by Method 9 only when particular
factor could affect the reading
*Windspeed - use Beaufort wind scale or hand-held anomometer,
be accurate to ±5 mph
"Wind Direction - direction wind is from, use compass, be
accurate to eight points
* Ambient Temperature - in °F or °C
""Wet Bulb Temperature - the wet bulb temperature from the
sling psychrometer
""Relative Humidity - use sling psychrometer; use local U S
Weather Bureau only if nearby
'Source Layout Sketch - include wind direction, associated
stacks, roads, and other landmarks to fully identify location of
emission point and observer position
Draw North Arrow - point line of sight in direct/on of emission
point, place compass beside circle, and draw in arrow parallel
to compass needle
Sun Location Line - point line of sight in direct/on of emission
point, place pen upright on sun location line, and mark location
of sun when pen's shadow crosses the observers position
""Comments - factual implications, deviations, altercations,
and/or problems not addressed elsewhere
Acknowledgment - signature, title, and date of company official
acknowledging receipt of a copy of VE observation form
"Observation Date - date observations conducted
"Start Time. Stop Time -beginning and end times of observation
period (e.g, 1635 or 4 35 p m).
"Data Set - percent opacity to nearest 5%, enter from left to right
starting in left column
"Average Opacity for Highest Period - average of highest 24
consecutive opacity readings.
Number of Readings Above (Frequency Count) - count of total
number of readings above a designated opacity
"Range of Opacity Readings:
Minimum - lowest reading
Maximum - highest reading
"Observer's Name - print in full
Observer's Signature, Date - sign and date after performing final
calculations
"Organization - observer's employer
"Certifier, Date - name of "smoke school" certifying observer and
date of most recent certification
Verifier, Date - signature of person responsible for verifying
observer's calculations and date of verification
Figure 4.2. Reverse side of form (Continued!
-------
Section 3.12.4
April 1983
VISIBLE EMISSION OBSERVA TION FORM
SOURCE NAME
ADDRESS
^"•"^
CITY [ M S
PHONE V. ^
/^
PROCESS EQUIPMENT 1 C
CONTROL EQUIPMENT ^*~*^
DESCRIBE EMISSION POINT
START X**^
HEIGHT ABOVE GROUND LfVff 5 TING MODE
DP
^VGHT RELA TIVE TO OBSER VER
JART STOP
1IRECTION FROM
TART S
OBSERVER
?OP
OP
V//W£ TYPE CONTINUOUS D
JplTIVEO INTERMITTENT D
W4 7£/? DROPLETS PRESENT*+Jftf WA TER DROPLET PLUME
NO a YE SO ATTACHED^ DETACHEDO
POINT IN THE PLUME A T WHICH OPACITY WAS DETERMINED
START STOP
DESCRIBE BACKGROUND
START STOP
BACKGROUND COLOR S*"$*
START STOP f P'S
WIND SPEED I C.IA
START STOP ^-'^
AMBIENT TEMP W
SMfff STOP
^V CONDITIONS
\>RT STOP
IfiD DIRECTION
TART STOP
>ET BULB TEMP
RH, percent
Source Layout Sketch Draw North Arrow
o
X Emission Point
Sun-fy- W/nd^ V J
Plume and = ^J^^rvers Pos(r(0n
Sraci: ,-^~^
,- -' 740° ---.__
5(yn Location Line
COMMENTS >^™V
vJf/
/ >yxi l/£ RECEIVED A COPY O&*H
S/GAM TURE lit
TITLE vJi
SE OPACITY OBSERVATIONS
J DATE
OBSERVATION DATE
^^
7
2
3
4
5
6
7
a
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
AVERt
HIGHE
0
15
30 t
I
_, i
T
I
T
I
I
G£ OPACITY FOP
ST PERIOD
START TIME
^5N
I
•»*_•'
^-^
V ^
RANGE OF OPACITY READINGS
MINIMUM
^
) 31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
0
55
1
57
58
59
.60
STOP TIME
15
30
45
\UMBER OF READINGS ABOVE
/ % WERE
MA XI MUM
OBSERVER'S NAME (PRINT)
OBSERVER'S SIGN A TURE
ORGANIZA TION [ 1C 1
CERTIFIED BY ^*— ^
VERIFIED BY
DATE
DATE
DATE
Figure 4 3 Functional sections of visible emission observation form
-------
April 1983
Section 3 12.4
Each major section of the form is
discussed in the following text. A
short explanation of each section's
purpose, a background explanation of
each data element, a description of
the type of information being sought,
and in some cases, appropriate
entries are included. These
discussions are keyed to Figure 4 3 by
corresponding capital letters, and it is
clearly indicated whether information is
required or recommended
A SOURCE IDENTIFICATION Provides
information that uniquely identifies
the source and permits the observer
to locate or make contact with the
source
Source name
Address
City
State
Phone
Zip
Source ID number
Source Name (Required) - include the
source's complete name If necessary
for complete identification of the
facility, the parent company name,
division, or subsidiary name should be
included.
Address (Required) - Indicate the
street address of the source (not the
mailing address or the home office
address) so that the exact physical
location of the source is known If
necessary, the mailing address or
home office address may be listed
elsewhere
City, State, Zip, Phone
(Recommended) - Self-explanatory
Source ID Number (Recommended) -
This space is provided for the use of
agency personnel and should be used
to enter the number the agency uses
to identify that particular source, such
as the State file number, Compliance
Data System number, or National
Emission Data System number
B PROCESS AND CONTROL DEVICE
TYPE Includes a several word
descriptor of the process and control
device, indication of current process
operating capacity or mode, and
operational status of control
equipment
Process equipment
Control equipment
Operating mode
Operating mode
Process Equipment (Required) - Enter
a description of the process
equipment that emits the plume or
emissions to be read The description
should be brief but should include as
much information as possible, as
indicated in the following examples:
Coal-Fired Boiler
#2 Oil-Fired Boiler
Wood Waste Conical Incinerator
Paint Spray Booth
Primary Crusher
Fiberglass Curing Oven
Reverberatory Smelting Furnace
Basic Oxygen Furnace
Operating Mode (Recommended) -
Depending on the type of process
equipment, this information may vary
from a quantification of the current
operating rate to a description of the
portion of a batch-type process for
which the emission opacity is being
read. For example, entries could
include "90 percent capacity" for a
boiler or "85 percent production rate"
for the shakeout area of a grey iron
foundry For a steel making furnace,
entries would include the exact part of
the process for which readings are
being made, such as "charging" or
"tapping." In some cases, the
observer may have to obtain this
information from a plant official
Control Equipment (Required) - Specify
the type(s) of control equipment being
used in the system after the process
equipment in question (e g , "hot-side
electrostatic precipitator")
Operating Mode (Recommended) -
Indicate the degree to which the
control equipment is being utilized at
the time of the opacity observations
(e.g., 75% capacity, full capacity, shut
down, off line) and the operating
mode (e g , automatic) The observer
will probably have to obtain this
information from a plant official
C EMISSION POINT IDENTIFICA TION
Contains information uniquely
identifying the emission point and
its spatial relationship with the
observer's position
Describe emission point
Start Stop
Height above
ground level
Start Stop
Distance from
observer
Start Stop
Height relative
to observer
Start Stop
Direct/on from
observer
Start Stop
Describe Emission Point (Required)
Include the identifying physical
characteristics of the point of release
of emissions from the source. The
description must be specific enough
so that the emission outlet can be
distinguished from all others at the
source In subsequent enforcement
proceedings, the observer must be
certain of the origin of the emissions
that were being read
Typical descriptions of the emission
outlet include the color, geometry of
the stack or other outlet, and the
location in relation to other
recognizable facility landmarks Any
special identification codes the agency
or source uses to identify a particular
stack or outlet should be noted along
with the source code used by the
observer The source of this
information should be recorded (e g ,
plant layout map or engineering
drawing)
Height Above Ground Level (Required)
- Indicate the height of the stack or
other emission outlet from its
foundation base This information is
usually available from agency files,
engineering drawings, or computer
printouts (such as NEDS printouts)
The information also may be obtained
by using a combination of a
rangefmder and an Abney level or
clmeometer The height may also be
estimated
Height Relative to Observer (Required)
- Indicate an estimate of the height of
the stack outlet (or of any other type
of emission outlet) above the position
of the observer This measurement
indicates the observer's position in
relation to the stack base (i e , higher
or lower than the base) and may later
be used in slant angle calculations
(see Section 3 1 2 6 and Subsection
4 4 6) if such calculations become
necessary
Distance From Observer (Required) -
Record the distance from the point of
observation to the emission outlet
This measurement may be made by
using a rangefmder If necessary, a
map also may be used to estimate the
distance
It is important that this
measurement be reasonably accurate
if the observer is close to the stack
(within 3 stack heights) because it is
coupled with the outlet height relative
to the observer to determine the slant
angle at which the observations were
made (see Figure 4 4). A precise
determination of the slant angle may
become important in calculating any
positive bias inherent in the opacity
readings
Direction From Observer (Required) -
Specify the direction of the emission
point from the observer to the closest
-------
Section 3.12.4
10
April 1983
of the eight points of the compass
(e.g., S, SE, NW, NE) or 45°. Use of a
compass to make this determination
in the following manner is suggested-
hold the compass while facing the
emission point, rotate the compass
until the North compass point lies
directly beneath the needle (which
will be pointing towards magnetic
North); then the point of the compass
closest to the emission outlet will
indicate the direction (Figure 4 5). A
map (plant layout) also may be used to
make this determination
Describe Emissions (Required) -
Include both the physical
characteristics of the emissions not
recorded elsewhere on the form and
the behavior of the resultant plume
The description of the physical
characteristics might include terms
such as lacy, fluffy, and detached
nonwater vapor condensibles
The terminology illustrated in Figure
4 6 can be used to describe plume
Observer/ Slant
"\45° Angle
behavior. The behavior can be used to
determine the atmospheric stability on
the day of the opacity observations.
Emission Color (Required) - Note the
color of the emissions. The plume
color can sometimes be useful in
determining the composition of the
emissions and will also serve to
document the total contrast between
the plume and its background as seen
by the opacity observer during the
observation period
Plume Type (Recommended) - Check
"continuous" if the duration of the
emissions being observed is greater
than 6 minutes Check "intermittent"
if the opacity cycle is less than 6
minutes Check "fugitive" if the
emissions have no specifically
designated outlet.
Water Droplets Present (May be
required) - Check "yes" or "no" as
appropriate. In some cases, the
presence of condensed water vapor in
the plume can be easily observed
/.' - Observer Path Length
L - Actual Path Length
Height
Relative to
Observer
-wl
Distance from observer
Figure 4.4. Slant angle relationships.
Observer
Stack
•o
Compass
Figure 4.5. Direct/on from observer is NE
D EMISSIONS DESCRIPTION Includes
information thai definitely
establishes what was observed
while making the visible emissions
determination
Describe emissions
Start Stop
Emission color
Start Stop
Water droplets
present
No D VesO
Plume type Continuous D
Fugitive D Intermittent D
If water droplet plume
Att ached D
Detached d
Point in the plume at which opacity was
determined
Start Stop
Plumes containing condensed water
vapor (or "steam plumes") are usually
very white, billowy, and wispy at the
point of dissipation, where the opacity
decreases rapidly from a high value
(usually 100%) to 0 percent if there is
no residual opacity plume contributed
by contaminate in the effluent.
To document the presence or
absence of condensed water vapor in
the plume, the observer must address
two points. First, is sufficient moisture
present (condensed or uncondensed)
in the plume initially? Second, if
enough moisture is present, are the
in-stack and ambient conditions such
that it will condense either before
exiting the stack or after exiting (when
it meets with the ambient air)? The
first question can be answered by
examining the process type and/or
the treatment of the effluent gas after
the process. Some common sources
of moisture in the plume are:
• Water produced by combustion
of fuels,
• Water from dryers,
• Water introduced by wet
scrubbers,
• Water introduced for gas cooling
prior to an electrostatic
precipitator, or other control
device, and
• Water used to control the
temperature of chemical
reactions
If water is present in the plume,
data from a sling psychrometer, which
measures relative humidity, in
combination with the moisture
content and temperature of the
effluent gas can be used to predict
whether the formation of a steam
plume is a possibility (see Section
3.126).
If Water Droplet Plume. (May be
required) - Check "attached" if
condensation of the moisture
contained in the plume occurs within
the stack and the steam plume is
visible at the stack exit Check
"detached" if condensation occurs
some distance downwind from the
stack exit and ttie steam plume and
the stack appear to be unconnected.
Point in the Plume at Which Opacity
was Determined (May be required) -
Describe as succinctly as possible the
physical location in the plume where
the observations were made. This
description is especially important in
the case where condensed water
vapor and/or secondary plume is
present. For example, were the
readings made prior to formation of
the steam plume? If the readings were
made subsequent to dissipation (e.g.,
in the case of an attached steam
-------
April 1983
11
Section 3.12.4
Coning
Fanning
Lofting
Looping
Fumigation
Figure 4.6. Plume behavior descriptors.
plume), then specify how far
downwind of the dissipation point and
how far downwind of the stack exit
the reading was made. This
information can be used to estimate
the amount of dilution that occurred
prior to the point of opacity readings.
Descriptions such as 4 feet above
outlet and 80 feet downstream from
outlet, 10 feet after steam dissipation
are appropriate.
Figure 4.7 shows some examples of
the correct location for making opacity
readings in various steam plume and
secondary plume situations
Describe Background (Required) -
Describe the background that the
plume is obscuring and against which
the opacity is being read. While
describing the background, note any
imperfections or conditions, such as
texture, that might affect the_ease of
making readings Examples of
background descriptions are roof of
roof monitor, stand of pme trees, edge
of jagged stony hillside, clear blue sky,
stack scaffolding, and building
obscured by haze
Background Color (Required) -
Accurately note the background color
(e g., new leaf green, conifer green,
brick red, sky blue, and gray stone).
OBSERVA TION CONDITIONS
Covers the background and ambient
weather conditions that occur during
the observation period and could
affect observed opacity
Describe background
Start Stop
Background color
Start Stop
Wmdspeed
Start Stop
Sky conditions
Start Stop
Wind direction
Start Stop
Ambient temp Wet bulb
Start Stop temP
Relative humidity
Area of Steam
Condensation
Attached steam plume
Read Here
Area of Steam
Condensation
Detached steam plume. In
rare cases, it may be
necessary to make readings
at the point of steam dis-
sipation if the plume is
more opaque at that point.
Read Here •
/preferred)
L
Or Here
Point of Steam
Dissipation
Secondary Plume Formation
i
Area of Steam
Condensation
Plume from a sulfuric acid
plant with detached steam
plume. Plume is clear at
stack exit. Secondary acid
mist is formed in area of
steam condensation.
Figure 4.7. Location for reading opacity under various conditions
-------
Section 3.12 4
12
April 1983
Sky Conditions (Required) - Indicate
the percent cloud cover of the sky
This information can be indicated by
using straight percentages (e.g , 10%
overcast, 100% overcast) or by
description, as shown below.
Term
Amount of cloud cover
Clear
Scattered
Broken
Overcast
10% to 50%
50% to 90%
>90%
Windspeed (Required) - Give the
wmdspeed accurately to ±5 miles per
hour The wmdspeed can be
determined using a hand-held
anemometer (if available), or it can be
estimated by using the Beaufort Scale
of Windspeed Equivalents in Table
4 1
Wind Direction (Required) - Indicate
the direction from which the wind is
blowing. The direction should be
estimated to eight points of the
compass by observing which way the
plume is blowing If this type of
estimation is not possible, the
direction may be determined by
observing a blowing flag or by noting
the direction a few blades of grass or
handfull of dust are blown when
tossed into the air Keep in mind that
the wind direction at the observation
point may be different from that at the
emission point; the wind direction at
the emission point is the one of
interest.
Ambient Temperature (Required) - The
outdoor temperature at the plant site
is measured by a thermometer (in
degrees Fahrenheit or centigrade)
obtained Irom a local weather bureau
or estimated Be certain to note which
temperature scale is used. This is
done m conjunction with the wet
bulb temperature and is only needed
when there are indications of a
condensing water droplet plume
Wet Bulb Temperature (May be
required) - Record the wet bulb
temperature from the sling
psychrometer This is to be done only
when there are indications of a
condensing water droplet plume
Relative Humidity (May be required) -
Enter the relative humidity measured
by using a sling psychrometer in
conjunction with a psychrometric
chart. This information can be used to
determine if water vapor in the plume
will condense to form a steam plume
(see Section 3126) If a sling
psychrometer is not available, data
from a nearby U S Weather Bureau
can be substituted
Table 4.1. The Beaufort Scale of Windspeed, Equivalents
General
description
Calm
Light
Gentle
Moderate
Fresh
Strong
Gale
Whole gale
Hurricane
Specifications
Smoke rises vertically
Direction of wind shown by smoke
drift but not by wind vanes
Wind felt on face; leaves rustle;
ordinary vane moved by wind
Leaves and small tw/gs m constant
motion, wind extends light flag
Raises dust and loose paper, small
branches are moved
Small trees in leaf begin to sway.
crested wavelets form on inland
waters
Large branches m motion; whistling
heard in telegraph wires, umbrellas
used with difficulty
Whole trees in motion; inconven-
ience felt in walking against the
wind
Tw/gs broken off trees; progress
generally impeded
Slight structural damage occurs
(chimney pots and slate removed)
Trees uprooted, considerable
structural damage occurs
Rarely experienced, accompanied
by widespread damage
Limits of velocity
33 ft (TO m) above
level ground, mph
Under 1
1 to 3
4 to 7
8 to 12
13 to 18
19 to 24
25 to 31
32 to 38
39 to 46
47 to 54
55 to 63
64 to 75
Above 75
F OBSERVER POSITION AND SOURCE
LAYOUT Clearly identifies the
observer's position in relation to the
emission point, plant landmarks,
topographic features, sun posit/on,
and wind direction
Source Layout Sketch
Draw North Arrow
Sun-fy Wmd-±
Plume and —
Stack
X Emission Point
Observers Position
140°
Sun Location Line
Source Layout Sketch (Required) -
This sketch should include as many
landmarks as possible. At the very
least, the sketch should locate the
relative position of the observed outlet
in such a way that it will not be
confused with others at a later date,
and clearly locate the position of the
observer while making the VE
readings. The exact landmarks will
depend on the specific source, but
they might include
Other stacks
Hills
Roads
Fences
Buildings
Stockpiles
Rail heads
Tree lines
Background for readings
To assist in subsequent analysis of
the reading conditions, sketch in the
plume (indicate the direction of wind
travel). The wind direction also must
be indicated m the previous section.
Draw North Arrow (Recommended) -
To determine the direction of north,
point the line of sight m the source
layout sketch in the direction of the
actual emission point, place the
compass next to the circle and draw
an arrow in the circle parallel to the
compass needle. A map (plant layout)
may also be used to determine
direction north
Sun's Location (Recommended) - It is
important to verify this parameter
before making any opacity readings.
The sun's location should be within
the 140° sector indicated in the layout
sketch; this confirms that the sun is
within the 140° sector to the
observer's back.
To draw the sun's location, point the
line of sight in the source layout
sketch m the direction of the actual
emission point, place a pen upright
along the "sun location line" until the
-------
April 1983
13
Section 3.12.4
shadow of the pen falls across the
observer's position Then draw the
sun at the point where the pen
touches the "sun location line "
G COMMENTS Includes all
implications, deviations,
disagreement with plant personnel
and/or problems of a factual nature
that have bearing on the opacity
observations and that cannot be or
have not been addressed elsewhere
on the form
Comments
Comments (May be required) - Note
all implications, deviations,
disagreements with plant personnel,
or problems of a factual nature that
cannot be or have not been addressed
elsewhere on the form Examples of
points to be included in this section
are:
• Changes in ambient conditions
from the time of the start of
readings
• Changes in plume color,
behavior, or other characteristics
• Changes in observer position and
reasons for the change, a new
form should also be initiated in
this case so that a new source
layout sketch may be drawn
• Difficulties encountered in plant
entry
• Conditions that might interfere
with readings or cause thsm to
be biased.
• Drawing of unusual stack
configuration (to show multiple
stacks or stack in relation to roof
line)
• Suspected changes to the
emissions or process during
observation.
• Unusual process conditions
• Additional source identification
information
• Type of plant (if not specified
elsewhere)
• Reasons for missed readings
• Other observers present
H COMPANY ACKNOWLEDGEMENT
Company acknowledgement of, but
not necessarily agreement with, the
opacity observations stated on the
form
I have received a copy of these opacity
observations
Signature
Title
Date
Signature (Recommended) - This
space is provided for the signature of
a plant official who acknowledges that
he/she has received a copy of the
observer's opacity readings. His/her
signature does not in any way
indicate that he/she or the company
concurs with those readings
Title (Recommended) - Include the
acknowledging official's company title
Date (Recommended) - The company
official should enter the date of
acknowledgment.
/ DA TA SET Opacity readings for the
observation period, organized by
minute and second This section
also includes the actual date and
start and stop times for the
observation period
Observation
date
A^
1
2
29
30
0
15
30
Start time
45
101^
31
32
59
60
0
Stop time
15
30
45
Observation Date (Required) - Enter
the date on which the opacity
observations were made
Start Time, Stop Time (Required) -
Indicate the times at the beginning
and the end of the actual observation
period The times may be expressed in
12-hour or 24-hour time (i e , 8.35
a m or 0835), however, 24-hour time
tends to oe less confusing
Data Set (Required) - Spaces are
provided for entering an opacity
reading every 15s for up to a 1 -hour
observation period The readings
should be in percent opacity and
made to the nearest 5 percent The
readings are entered from left to right
for each numbered minute, beginning
at the upper left corner of the left-
hand column, labeled row "M 1 "
(minute 1) and column "s 0" (0
seconds) The next readings are
entered consecutively in the spaces
labeled M 1, s 1 5, M 1, s 30; M 1, s
45, M 2, sO, M 2, s 15, etc
If, for any reason, a reading is not
made for a particular 15-second
period, that space should be skipped
and an explanation should be provided
m the comments section Also a dash
(-) should be placed in the space
which denotes that the space is not
just an oversight
J DATA REDUCTION Basic analysis of
the opacity readings to allow
preliminary compliance appraisal m
accordance with EPA Reference
Method 9
Average opacity
for highest period
Number of read-
ings above
% were
Range of opacity readings
Minimum Maximum
A verage Opacity for the Highest
Period (Required) - Enter the average
of the sum of the highest 24
consecutive readings (6-mmute set).
In other words, identify the 24
consecutive readings that would sum
to the greatest value and then divide
this value by 24 to get the average
opacity for that set of readings. Note:
The average should not include a time
lapse for which a valid reading could
have been taken but was not (see
Section 3126).
Number of Readings Above . % Were
. (Recommended) - Indicate an
optional frequency count of the
opacity readings above a particular
value The value is chosen according
to the opacity standard for the
emission point and is generally the
actual value of the standard
Method 9 does not specify the use
of frequency counting to reduce data,
but many States use it to determine
compliance with their time exemption
opacity standards For example, a
State regulation might specify that
opacity of a specific type of emission
source is not to exceed 20 percent for
more than 3 minutes in an hour If
more than 1 2 readings out of 240
exceed 20 percent in an hour-long
observation period, that State may
consider that source out of
compliance For example,
14 readings out of 240 readings (1
hour) are above 20 percent opacity
14 x 15 s per reading = 210 s
= 35 minutes of readings above the
standard
Range of Opacity Readings (Required)
- Enter the highest and lowest opacity
readings taken during the specified
observation period.
K OBSERVER DATA Information
required to validate the opacity data
Observer's name (print)
Observer's signature
Date
Organization
Certified by
Verified by
Date
Date
-------
Section 3.12.4
14
April 1983
Observer's Name (Required) - Print
observer's entire name
Observer's Signature/Date
(Recommended) - Self-explanatory
Organization (Required) - Provide the
name of the agency or company that
employs the observer.
Certified By (Recommended) - Identify
the agency, company, or other
organization that conducted the
"smoke school" or VE training and
certification course where the
observer obtained his/her most
current certification.
Date (Required) - Provide the date of
the most current certification
Verified By (Recommended) - The
actual signature of someone who has
verified the opacity readings and
calculations, usually the observer's
supervisor, or the individual who is
responsible for his/her work
Date (Recommended) - Provide the
date of verification.
4.3.3 Facility Operating Data - It is
strongly recommended that a VE
inspection/observation conclude with
a source inspection if opacity values
are in excess of the standard. The
observer would first follow the plant
entry procedure in Subsection 4 1 and
then follow the indicated procedure to
obtain facility operating data.
After the VE determination, it is
recommended that the following
source information be determined:
1 Were the plant and the source of
interest operating normally at the
time of the VE evaluation?
2. Are there any control devices
associated with the source?
3. Were the control devices
operating properly?
4 Have there been any recent
changes in the operation of the
process or control devices?
5. Have any malfunctions or
frequent upsets in the process or
control devices been noted and
reported (if required by the
agency)?
6. Is the plant operator aware of
excessive visible emissions and
have any corrective steps been
taken to alleviate the problems?
7. Are there any other sources of
visible emissions in close
proximity to the source in
question that may interfere with
reading the plume opacity or
contribute to the appearance of
the plume?
4.3.4 Photographs - It is suggested
that photographs be taken before and
after the observation is made, not
during the observation period
Conditions should be recorded as they
existed at the time of the observation.
The use of a 35-mm camera is
recommended to ensure good
photographs
Each photograph should be identified
with the date and time, the source,
and the position from which the
photograph was taken
4.4 Special Observation Problems
The VE observer constantly should
be aware that his/her observations
may be used as the basis of a
violation action and subject to
questioning as to the reliability of the
observations. Therefore, he/she must
also be aware that under some
conditions or situations it may be
difficult or impossible to conduct a
technically defensible visible
emissions observation
This section discusses some of the
most prevalent difficult conditions or
special problems associated with the
visible emission observation. Each
discussion is directed toward defining
the problem, indicating how it might
invalidate readings taken, and
addressing possible solutions and/or
ways to minimize the invalidating
effects
Not all of these discussions offer a
complete solution for a particular
problem; thus, it is important for the
individual observer to keep in mind
the purpose of the visible emission
observation when considering exactly
what action to take when faced with a
special problem.
4.4.1 Positional Requirements -
Valid VE evaluations can be
conducted only when the sun is
properly positioned at the observer's
back. Failure to adhere to this
positioning can result in significant
positive bias caused by forward light
scatter in opacity readings. Because of
this overriding constraint, some times
and locations make it difficult for the
observer to meet other opacity reading
criteria, e.g., reading the narrow axis
of a rectangular stack, reading a
series of stacks across a short axis to
prevent multiple plume effects, and
obtaining a contrasting background
Plant topography also may generate
constraints that restrict viewing
positions to one or more locations
The observer will be aided in
determining the best observation
location by following the criteria listed
below
1. Make sure that the emission
point is north of the observation
point.
2. Obtain a clear view of the
emission point with no
interfering plumes
3 Be sure that rectangular stacks
are read across the narrow axis
and multiple stacks are read
perpendicular to the line of
stacks
4. Minimize the slant angle by
moving a sufficient distance from
the stack or to an elevated
position (see Subsection 4.44).
5 Find a contrasting background or
a clear sky background.
6. Finally, determine the best time
of day for observations based on
the daily sun tracks at that
location
Collaborative studies of the
performances of trained observers
have indicated that, with the
exception of the positive bias caused
by having the improper sun angle,
visible emission observation biases
tend to be negative. Thus, if viewing
conditions are not ideal and a
negative bias (lower value) results,
opacity readings may not provide the
true measure of plume opacity
required to correlate to mass
emissions or control equipment
efficiency. However, readings that
indicate a violation can be regarded as
the minimum opacity; therefore,
documentation of the violation is
valid.
In situations where the observer
must make plume opacity readings
when all the criteria for correct
viewing cannot be met, all
extenuating circumstances must be
documented on the VE evaluation
form
4.4.2 Multiple Sources/Multiple
Stacks - An observer is sometimes
compelled to evaluate a stack that
discharges emissions from more than
one source or to evaluate a single
source that has more than one
emission point
In the case where one stack serves
more than one emission source, the
observer may be able to isolate the
emissions from one source as a result
of intervals of operation, or by
requesting the facility's cooperation in
temporarily shutting down the other
source(s) Otherwise, the observer
should proceed with the VE
observation and document the
situation completely on the VE
evaluation form
In the case of multiple emission
points for a single source (e g., in
positive-pressure baghouses and
multiple vents in roof monitors),
Section 2.1 of Method 9 directs the
-------
April 1983
15
Section 3.12.4
observer to read multiple stacks
independently if it is possible to do so
while meeting sun position
requirements. If it is necessary to get
an overall reading for the group of
stacks, the following set of formulas
can be used to calculate this reading
from the individual opacity values
100
1-_Q2_ = T2
100
1 --ON_ = TN
100
T-i X T2 X .. TN = TT
100 X(1 -TT) = OT
where
Oi= % opacity of 1st plume
62= % opacity of 2nd plume
ON= % opacity of nth plume
T-i = Transmittance of 1 st plume
Ta= Transmittance of 2nd plume
TN= Transmittance of nth plume
TT = Total transmittance
OT= % total opacity
4.4.3 High Winds - Occasionally the
crosswind conditions are unfavorable
during field observations of plume
opacity. When the winds are strong
enough to shear the emissions at the
stack outlet, it is difficult for the
observer to make an accurate and fair
VE observation. Strong crosswmds
can have several effects on the
plume:
1. The plume becomes essentially
flattened and is no longer conical
in shape thus the path length
and apparent opacity increases
2. The plume is torn into fragments
and becomes difficult to obtain a
representative reading
3. The plume becomes diluted, and
the apparent opacity is lowered
The observer can compensate
somewhat for the effect of flattening
by reading the plume downwind of
the stack, after it has reformed into a
cone. The dilution effect of high
winds, which lowers the apparent
opacity, presents more of a problem
Because of the negative bias
introduced, the effectiveness of
Method 9 as a control tool under
these conditions is diminished If a
violation is still observed under these
conditions, it should be considered
valid. It is recommended that
whenever feasible, VE observations be
suspended until the wind-caused
interferences have abated.
4.4.4 Poor Lighting - Poor lighting
conditions for VE observations usually
involve one or more of the following
(1) a totally overcast sky, (2) early
morning or late afternoon hours, or (3)
nighttime Each of these three lighting
conditions has the same net effect on
the plume; they differ slightly only in
the cause of the poor illumination
When the amount of available
sunlight is below a certain level, the
contrast between a white plume and
the background decreases. Therefore,
readings are not recommended in
either the early morning hours (at or
approaching dawn) or late afternoon
hours (at or approaching dusk)
Nighttime viewing obviously
represents the most severe of poor
lighting conditions. Some agencies
have attempted, with mixed results, to
use night vision devices (light
intensification scopes) for plume
viewing and testing in the dark
Others have achieved better results by
placing a light behind the emissions,
which provides a very high contrast
background. For this method, it is
important to select a source of light of
moderate strength that does not
cause the ins of the eye to close.
4.4.5 Poor Background - The color
contrast between the plume and the
background against which it is viewed
can affect the appearance of the
plume as viewed by an observer Field
studies have corroborated predictions
of the plume opacity theory by
demonstrating that a plume is most
visible and has the greatest apparent
opacity when viewed against a
contrasting background.
Consistent with these findings is
the fact that with a high contrast
background, the potential for positive
observer bias is the greatest
However, field trials consisting of 769
sets of 25 opacity readings each have
shown that for more than 99 percent
of the sets, the positive observer error
was no greater than 7 5 percent
"opacity.2
Also consistent with these findings
is the fact that as the contrast
between the plume and its
background decreases, the apparent
opacity decreases; this greatly
increases the chance for a negative
observer bias Under these conditions,
the likelihood lessens of a facility
being cited for a violation of an
opacity standard because of observer
error.
When faced with a situation where
there is a choice of backgrounds, the
observer should always choose the
one providing the highest contrast
with the plume because it will permit
the most accurate opacity reading
However, if a situation arises where
other constraints make it impossible
to locate an observation point that
provides a high contrast background,
the observer may read against a less
contrasting one with confidence that a
documented violation should be
legally defensible.
4.4.6 Reduced Visibility -
Environmental factors at the time of
observation also are of concern to
the visible emissions observer.
Environmental considerations include
rain, snow, or other forms of
precipitation, and photochemical smog
buildup, fog, sea spray, high humidity
levels, or any other cause of haze.
These environmental factors create a
visual obscuration that can increase
the apparent opacity of the plume, but
more commonly reduce the
background contrast and thus
decrease the apparent opacity.
In recognition of the problems that
could result from reduced visibility
caused by environmental factors, the
amended Method 9 (November 12,
1974) states, in paragraph 2.1 of the
Procedures Section: "The qualified
observer shall stand at a distance
sufficient to provide a clear view of
the emissions ..." A "clear view"
must be interpreted as a view free
from obstacles or interferences. Most
problems caused by reduced visibility
can be alleviated simply by making
the observations on another day.
4.4.7 Tall Stacks/Slant Angle -
When an observer's distance from the
stack approaches 1/4 mile
(approximately 1300 feet, or a little
over four football fields), the ambient
light scattering may begin to have an
adverse effect on the contrast
between the plume and the
background. Also, if the sky is
overcast or hazy on the day of
observation, the farther the observer
is from the emission point, the more
the haze interferes with the view of
the plume and hence, the less reliable
the readings.
On the other hand, the
recommendation that the observer
stand at least three stack heights from
the stack being observed is intended
to ensure that the width of the plume
as it is viewed is approximately the
same as it is at the stack outlet. As
the observer gets closer to the stack
and the viewing (slant) angle
-------
Section 3.12.4
16
April 1983
increases, the observed path length
also increases; this causes the
observed opacity to increase because
the observer is reading through more
emissions. These relationships are
shown in Figure 4.8 At an observer
distance of three stack heights, which
corresponds to a slant angle of 18°,
the deviation of observed opacity from
actual opacity decreases to 1 percent
opacity, which is considered
acceptable (see Section 3.12.6).
The three-stack-heights relationship
only occurs if the observer and the
base of the stack are in the same
horizontal plane. If the observer is on
a higher plane than the base of the
stack, then the minimum distance for
proper viewing can be reduced to less
than three stack heights; conversely,
if the observer's plane is lower than
that of the stack base, then the
minimum suggested distance will be
greater than three stack heights (see
Figure 4 8) The real determining
factor is the slant angle To assure no
more than a 1 percent opacity
deviation of observed opacity from
actual opacity, the observer must have
a visual slant angle of 18° or less.
4.4.8 Steam Plumes - Under certain
conditions, water vapor present in an
effluent gas stream will condense to
form a visible water droplet or "steam"
plume Because the NSPS (specifically
Method 9) and almost all SIP's
exclude condensed, uncombmed
water vapor from opacity regulations,
the VE observer must be careful that
he/she does not knowingly read a
plume at a point where condensed
water vapor is present and record the
value as representative of stack
emissions.
Knowledge of the kind of process
that generates the emissions being
read and simple observation of the
resultant plume almost always allows
the observer to determine if a steam
plume is present. Steam plumes are
commonly associated with processes
or control equipment that introduce
water vapor into the gas stream.
These sources include
• Fuel combustion,
• Drying operations,
Plume
H
— Y=3H
Figure 4.8. Observer distance, observed path length relationships
• Wet scrubbers,
• Water-induced gas cooling prior
to an emissions control device,
and
• Water-induced chemical reaction
cooling.
Also, observation of steam plumes
will reveal that they are usually very
white, billowy, and have an abrupt
point of dissipation. At the point of
dissipation, the opacity generally
decreases rapidly from a high value
(usually 100%) to a low value
Depending on the moisture and
temperature conditions in the stack
and in the ambient air, steam plumes
may be either "attached" or
"detached." An attached steam plume
forms within the stack and is visible
at the exit; a detached steam plume
forms downwind of the stack exit and
does not appear to be connected to
the stack. In cases when it is not clear
whether a steam plume is present or
when an observer would like to
predict the formation of a steam
plume, the stack gas conditions may
be used m conjunction with the
ambient relative humidity to make the
prediction (see Section 3.12 6)
When a steam plume is present, the
particulate plume is read at a point
where 1) no condensed water vapor
exists, and 2) the opacity is the
greatest. In the case of a detached
steam plume, this point is usually at
the stack exit, prior to the water vapor
condensation, in the case of an
attached steam plume, it is usually
slightly downwind of the point of
steam plume dissipation (for
examples, see Figure 4.7) The observer
should always carefully document the
point chosen
4.4.9 Secondary Plume Formation -
Some effluent gas streams contain
species that form visible mists or
plumes by a physical and/or cherpical
reaction that occurs either at some
point in the stack or after the
emissions come m contact with the
atmosphere This situation is known
as secondary plume formation
Examples of such secondary plume
formation include
• A change in the physical state of
a compound condensing from a
gas into a liquid, such as
vaporized hydrocarbon
condensing into an aerosol or a
solid.
• A physiocochemical reaction
between two or more gaseous (or
m some cases, liquid) species in
a plume, such as the
condensation of ammonia, sulfur
dioxide, and water vapor to form
-------
April 1983
17
Section 3.12.4
paniculate ammonium sulfite or
the condensation of sulfur
tnoxide and water vapor to form
sulfunc acid mist
• A physiocochemical reaction
between species in a plume and
species in the atmosphere, such
as the formation of NaOa
Secondary plumes are sometimes
found in the following processes (with
these suspected secondary reactions)1
• Coal- and oil-fired cement kilns
(S03 + H2O - H2S04 mist)
or [NH3+ S02 + H2O -
(NH4)2 S03]
• Fossil-fuel-fired steam
generators (S02 + H2O - H2S04
mist)
• Sulfunc acid manufacturing (SOs
+ H20 - H2S04 mist)
• Plywood and particleboard wood
heating (organic vapor — organic
mist)
• Glass manufacturing (inorganic
vapor — organic aerosol)
As in the case of steam plumes,
secondary plumes can be attached or
detached, depending on the specific
condensation reaction and the
ambient conditions. For example, a
secondary plume will be attached if a
reaction between plume species
occurs in the stack and the stack
temperature is sufficiently low to
cause condensation of the reaction
products to a visible liquid or solid
phase A detached secondary plume
will be evident when the reaction
does not occur until the gas stream
comes in contact with the
atmosphere. The degree of
detachment depends on the ambient
conditions, the degree of mixing
between the effluent and the
atmosphere, and the specific
reaction(s) involved
Secondary plumes may occur with
or without an accompanying steam
plume, and it is important that the
observer be able to distinguish
between the two Unlike steam
plumes, secondary plumes are often
persistent (they do not dissipate
rapidly), are usually bluish white (due
to the fine particles present), and are
grainy rather than billowy
To read a secondary plume, the
observer must locate the densest
point of the plume where water vapor
is not evident and make the readings
at that point This point may occur in
several different areas, depending on
the type of secondary plume An
attached secondary plume will usually
be read at the stack exit if an attached
steam plume is not present, if an
attached steam plume is present, the
secondary plume must be read at the
point of steam dissipation A detached
secondary plume will usually be read
slightly downwind of the area of
formation, assuming there is no
interfering condensed water vapor
Under some conditions, a secondary
plume may not fully condense until
some distance downstream of the
point of formation, in this case, the
observer simply looks for the densest
area of the plume and makes the
reading at that point It is especially
important in reading a secondary
formation plume to describe fully the
point at which the reading was taken
and the exact appearance of the
plume. (Refer to Figure 4 7 for one
example of where to read a secondary
plume.)
4.4.10 Fugitive Emissions - Fugitive
emissions are those emissions that do
not emanate from a conventional
smoke stack or vent Examples of
these nonconventional emissions
include'
• Dusty or unpaved roads
• Stock or raw material piles under
windy conditions or when moved
by machinery
• Conveyor belts, pneumatic lifts,
clamshells, and draglines
• Cutting, crushing, grinding, and
sizing of minerals or other
materials
• Plowing, tilling, and bulldozing
• Open incineration
• Demolition activities
• Roof monitors or building vents,
especially In foundries, iron and
steel facilities, and related
industries
Because of the irregular shape of
their emission point or area,
conducting a conventional Method 9
test on fugitive emissions may appear
difficult, however, it usually involves
only relatively minor adjustments
Commonly used procedures for
observation of fugitive emissions are
listed below
1 If possible, isolate the particular
emission from other emissions
by choosing an appropriate
position for observation
2 Adhere to the lighting
requirements of Method 9 by
keeping the sun in the 140°
sector to the observer's back
3 Also adhere to Method 9 in
selecting a position with regard
to wind direction and a
contrasting background
4 Whenever possible, select the
shortest path length through the
plume
5 Before taking readings, view the
emission for several minutes to
determine its characteristics
Changes that may occur in the
airborne particulate pattern over
time are important to note and to
consider in selecting a viewing
point
6. Select the line of sight and the
viewing point in the emissions so
that, on the average, the densest
part of the emissions will be
observed It is recommended that
all subsequent readings in a data
set be taken at the same relative
position to the emission source
7 The configuration of the emission
point or area may necessitate
taking readings at a point
downwind where the emissions
have assumed a more
conventional plume shape
8 If the plume cannot be viewed
through a nearly perpendicular
angle, corrections may be
necessary
4.4.11 Intermittent Sources - Some
sources release visible emissions
intermittently rather than
continuously, e g., coke ovens, batch
operations, single chamber
incinerators, malfunctioning control
equipment (in rapping, bag shaking,
etc ), boilers during soot blowing, and
process equipment during startup
Intermittent emissions may have a
high opacity for a short time and a
low or negligible opacity at other
times This high-low cycle may be
repeated at fairly regular intervals If a
source is in violation (or in continuous
compliance) of the applicable standard
over the 6-mmute averaging time
required by Method 9, it does not
pose a problem to the visible
emissions observer If the pollutant-
emitting operational cycle of a source
is less than 6 minutes in duration,
however, that source may be out of
compliance only for a portion of each
6-minute averaging period, which will
make it difficult or impossible to
document a violation if the data is to
be reduced to a 6-mmute average
If the source is not covered by a
NSPS or a State Implementation Plan
that specifies the explicit use of
Method 9 or another specified
modification to Method 9, another
technique for reading intermittent
emissions of less than a 6-mmute
duration is to use Method 9
procedures but reduce the averaging
time to about 3 minutes This
reduction will allow the observer to
tally the number of 3-mmut.e
violations that occur Analysis of
many data sets has confirmed that
using this method sacrifices little or
no accuracy
-------
Section 3.12.4
18
April 1983
In all cases where sources are not Table 4. 2. Activity
subject to NSPS or other federally
promulgated standard, the existing
State regulations and specified opacity . • .
observation methods (if any) must be
used. Two other techniques that have Per/meter survey
been used to document intermittent
emissions are the "stopwatch"
technique (measuring the total
accumulated time that the opacity
exceeds the applicable standard) and Plant entry
the time-aggregate data reporting
technique (taking readings every 1 5
seconds, tallying the number of
readings exceeding the standard, and
multiplying this number by 15 seconds
to determine the amount of time the
source is out of compliance during the
observation period) Many State
agencies use these latter techniques,
and have adopted their methods in
their SIP rules and regulations. EPA V£ Determination
currently has studies underway to ' Position
evaluate the accuracy and reliability of
these nonaveragmg techniques
2. Observations
3. Field data: VE
observation form
4. Facility operating
data
Special observation
problems
Matrix for Visible Emission Determination
Frequency and A ction if
Acceptance method of requirements
limits measurement are not met
Completed per-
imeter survey
Observer should
follow protocol
as suggested in
Subsec 4.2 and
adhere to con-
fidentiality of
data
In accordance
with Subsec
4.3.1
Taken in accord-
ance with Sub-
sec 4 3. 1
Completed data
form
Pertinent pro-
cess data
obtained
N/A
Prior to, follow-
ing, and during
(if warranted)
the VE deter-
mination
Entry prior to
taking VE read-
ings only if
necessary, entry
after VE readings
to provide plant
representative
with data and/ or
to obtain neces-
sary plant pro-
cess data
Take a position
for observation
as described in
Subsec 4 3. 1
and document
on data form
Make VE deter-
mination as
described in
Subsec 4.3.1
Complete data
form as per in-
structions and
examples in
Subsec 4.3.2
After VE obser-
vations, obtain
facility data per
Subsec 4.3.3
Refer to Subsec
4.4 when condi-
tions do not per-
mit VE observa-
tion under pro-
per position, etc.
N/A
N/A
-
Follow instruc-
tions under
special problems
(Subsec 4.4)
when a proper
position cannot
be assumed
As above
Complete miss-
ing data (if
possible) or give
rationale for in-
complete data
Data must be
obtained as soon
as possible after
VE observation
N/A
N/A = not applicable.
-------
April 1983
Section 3.12.5
5.0 Postobservation Operations
Table 5.1 at the end of this section
summarizes the quality assurance
activities for postobservation
operations. These activities include
preparation of reports and data
summaries and validation.
5.1 Data Summary
The opacity observations are
recorded on data forms such as those
shown in Figures 4 1 and 4 2. Figure
5.1 is a summary data form for
manual calculations This form and
the calculation procedures are
discussed in detail in Section 3126.
It is recommended, however, that a
computer be used when reducing
large quantities of data and to avoid
calculation errors.
5.2 Reporting Procedures
Recording opacity observation data
on a three-part form is most
convenient One part can be given to
the appropriate facility personnel
immediately following the on-site field
observation if this is the agency policy
or procedure, one part should be
given to the Agency, and one part
should be maintained in the
observer's file. The data form should
be completed on-site, and it should be
signed by the observer, the facility
representative (if applicable), and the
Company
Start time /33O
Admiral fokJCr P/e(/lf~ Date
Emission point Oil
75 J,//
data validator. All corrections must be
initialed The file copy should be
signed by the data validator
Inspection forms alone may not be
adequate for documenting an
enforceable violation and can be
supplemented by a narrative report. It
is recommended that a summary
report be made containing the
following information:
1. Name and location of facility,
date and time of inspection,
name of inspector, and name of
company official(s) contacted.
2. Brief description of the specific
process information gathered,
. Location
Start
no
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
Total
opacity
sw
«««
TO
860
VK>
315
Average
opacity
3fc.S
3fc.T
it.fc
35*
3&0
35.2.
Start
no.
37
38
39
40
41
42
43
44
,_45_
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
Maximum averane 3*
Total
opacity
Average
opacity
Start
no
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
roi
102
103
104
105
106
107
108
Total
opacity
A verage
opacity
Start
no.
109
no
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
Total
opacity
Average
opacity
Start
no
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
Total
opacity
A verage
opacity
Start
no
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
Total
opacity
A verage
opacity
'• v % Start number of six minute averaae '
Number of nonoverlappin,
Calculated by ^LS^JT^L
verages in excess of standard o Listing start numher of these averages lj'*-i ou>// /:->
ir Datelkiti/iXtiSiReviewed by I f\. ^e^/£U/£/£ Date I? JUtf ff&i
Figure 5.1 Visible emission summary data sheet
-------
Section 3.12.5
April 1983
particularly any unusual
occurrences.
3 Description of the equipment that
was inspected and its operating
mode at the time of inspection
4 Notation of any excessive
emissions seen and
corresponding data from opacity
continuous emissions monitor if
available.
5. Explanation of excessive
emissions, if available, and
corrective actions being taken
6 Summary of emission points not
m compliance.
7 Recommendations for followup
action.
One copy of the report, an updated
plot plan, photographs, and other
pertinent data should be placed in the
Agency file Whenever a violation is
noted, it is EPA policy to notify the
facility of the alleged violation and to
permit them to review the evidence
against them in a meaningful way
The importance of a good file cannot
be overstated This file represents the
official Agency documentation of
compliance history, the latest
information on the source's operation
and compliance status The file also
provides the means of communicating
source conditions to other staff
members A thorough and accurate
historical record on source inspections
and opacity readings is essential to
good operation and any necessary
compliance/enforcement actions
5.3 Data Validation
All opacity observation data
obtained for compliance determination
should be validated by senior staff
assigned this responsibility Data
validation procedures are described in
References 1 6 and 1 7. These data
should be checked to the extent
possible for their completeness, the
correctness of source, the emission
point and description, the background,
and the process and control
equipment in use The calculation of
the average opacities and highest
average opacity also should be
checked All calculation checks should
agree within acceptable roundoff
errors. If possible, any questionable
data should be reviewed with the
observer Ideally the data validation
should occur as soon as possible after
the observations are recorded so that
questions may be resolved Any other
calculations made for the purpose of
supporting the data (e g , the effect of
angle of observation on the observed
opacity) should also be verified Note.
Any corrections in the data must be
forwarded to all interested parties so
that they may correct their records (a
data form should have been given to
them after the opacity observations
were completed)
5.4 Equipment Check
A check of the equipment following
the opacity observations helps to
ensure the quality of the data Any
indication of equipment
damage/malfunction should be
recorded on an equipment log and
noted for purposes of data validation
The malfunctioning equipment should
be repaired, adjusted, or replaced so
that the equipment will be available
for subsequent on-site field
observations
TableS. 1. Activity Matrix for Postobservation Operations
Frequency and Action if
Acceptance method of requirements
Activity limits measurement are not met
Data summary
Reporting procedures
Data validation
Equipment check
Completed data
form
Completed re-
port and data
forms
All checks
should agree
within accept-
able roundoff
error
All equipment/
apparatus
should be
checked for sat-
isfactory opera-
tion after each
VE observation
day
See Subsec
3126 for in-
structions for
calculations
Use 3-part form
as suggested in
Subsec 52
Make data valid-
ation check as
soon as possible
after VE obser-
vation
Check equip-
ment for
damage/ma/-
functions
Complete the
data summary
Complete the
necessary data
forms and re-
porting proce-
dure
Forward all
corrections of
the data/calcul-
ations to the
interested
parties
Note on equip-
ment log and
repair, adjust or
rep/ace the
equipment
-------
April 1983
Section 3.12.6
Three types of calculations are
described in this section (1) the
calculation of the average opacity for
the specified time period (usually 6
mm, or 24 observations recorded at
15-s intervals), (2) the calculation of
the path length through the plume
(seldom needed), and (3) the
prediction of steam plume formation
(seldom needed). In the first
calculation, the 6-min running (or
rolling) averages may be required To
minimize errors in the calculations,
another individual should check all
calculations for each VE
determination for compliance If a
difference greater than a typical
roundoff error is detected, the
corrections should be made and
initialed by the one making the
correction. Table 6.3 at the end of this
section summarizes the quality
assurance activities for these
calculations.
6.1 Calculation of Average
Opacity
Figure 6 1 shows actual opacity
data taken at one company
(unspecified) for two 6-min periods
Note: Any corrections made by an
observer must be initialed and the
corrected value used in the
computation of an average The
calculations can be checked by
obtaining the row and column
subtotals, the totals of these subtotals
must be identical.
Running 6-min averages are
calculated from data on Figure 6.2
and reported as described below
Running averages can include a time-
lapse break in opacity readings when
caused by an element that makes taking
a valid reading difficult (e g , fugitive
emissions, improper background, or
process shutdown). Running averages
should not contain time-lapse breaks
in the readings as a result of the
observer's desire not to take visible
emission data for personnel reasons
when conditions exist that would
allow the observer to take valid
opacity data (e g., eye strain or no
desire to continue readings) Figure
6.3 is included to provide an easy
reference between the VE reading
time on Figure 6 1 and the start
number on Figure 6.2 The start
numbers are used to find the
corresponding observation time for
the beginning of the calculated six
minute average
6.0 Calculations
Determination of the running
average is generally performed by
computer or by a hand calculator The
main purpose of the calculations is to
determine the number of 6-mm
periods in excess of the standard and
the greatest value for any 6-min
period It is also suggested, but not
required, that the opacity readings be
plotted on a graph showing percent
opacity versus time, with a straight
line connecting each subsequent
reading.
6.1.1 Use of Computer for
Calculations - It is highly
recommended that a computer be
used to calculate and plot data
Programming will vary with the
language used by the particular
computer, but the basic principle is as
follows
Input.
1 Enter all VE readings with their
corresponding start number or
identifying start time
Computation:
1. The first average opacity reading
is obtained by averaging the first
24 opacity readings.
2 Each succeeding running
average is obtained from the
previous one by adding the next
observation reading and
subtracting the first observation
in the series and then dividing by
24 (assuming 6-mm running
average).
Printout
1. The computer should print all VE
readings with their
corresponding number or time
This printing will ensure that all
readings have been entered
properly
2. The computer should search all
averages and print the highest
average opacity and its
corresponding number or time
interval
3 Starting at the first interval, the
computer should search for all
nonoverlapping 6-mmute periods
in excess of the standard Each
interval's average opacity value
and corresponding number or
time should be printed out
4 Finally the computer should plot
VE readings versus time
intervals. If the computer has a
plotter, it should be used If not,
the values can be plotted without
connecting lines If desired, the
computer can bracket intervals in
excess of the standard.
6.1.2 Use of Hand Calculator for
Calculations - When a hand calculator
is used, the calculation procedures
are the same as those for the
computer, except that they must be
performed manually All data should
be recorded on the VE Summary Data
Sheet (see Figure 6 2) if desired To
avoid calculating average opacity
values that are less than the standard,
the following procedure can be used.
The total value for the 24 readings
should be calculated first, and the
total opacity should be entered at
Start no 1
Each succeeding total value can be
obtained and recorded by adding the
difference between the value dropped
and the one added. These calculations
can be performed easily without a
calculator If desired, the average
opacity reading could then be
calculated only for those totals that
exceed the total allowable opacity
limit (e g , 20% x 24 = 480). Therefore,
a total opacity of 480 or greater would
be an exceedance of a 20 percent
opacity standard Method 9 does,
however, require that the accuracy of
the method be taken into account
when determining possible violations
of applicable opacity standard
It is suggested that when the
opacity standard has been exceeded
for any 24 consecutive readings, the
data be hand-plotted with each VE
reading versus its time interval These
plots fit best on graph paper scaled 10
lines to the inch Each 1 5-second
reading can be plotted at 1/2 spacing,
thereby allowing 20 readings per inch
If desired, intervals of opacity in
excess of the standards can be
marked on this plot It is much easier
to visualize a trend in opacity with
time with such a graphical
presentation than with tabulated
numerical readings as shown in
Figure 6 4
6.2 Calculation of Path
Length Through the Plume
The observer should be located so
that only one plume diameter is being
sighted through In rare cases, the
observer has no choice but to be
relatively close to the stack so that the
view is up through the plume rather
than across it. In these cases, this
extra width of plume should be
-------
Section 3 12.6
April 1983
SOURCE NAME
AP/1/&A/- PO\jJ£& P6A^^•
ADDRESS
///£. OC£-J\fJ /\
CITY
PHONE
STATE
VA
ZIP
SOURCE ID NUMBER
/Y£OS 4S7/U
PROCESS EQUIPMENT
0(1- Ftg££> ($&l(j£,SL
CONTROL EQUIPMENT
&t££TROST1KtfC- pK£OF/T/VlC
OPERA TING MODE
^AS£/-OAJ>
OPffl/l r//VG /MODf
v*' Ovl 00/1 1/'
'p*-
/%ArrE CONTINUOUS sf
] INTERMITTENT D
IF WA TER DROPLET PLUME
ATT A CHED D Of TA CHED D
POINT IN THE PLUME A T WHICH OPACITY WAS DETERMINED
START /O/A3O\/£. ffTKX.&tTsTOP ^^
DESCRIBE BACKGROUND
START S/CV STOP U /k
BACKGROUND COLOR gjjjr,
START &LU£. STOP^ZMTt
WIND SPEED
START /5mp>\ STOpZQ^h
AMBIENT TEMP
STOP -
Plu
Sta
•X
/
Wmd^
me and ~ ^^.
ck ^~^\
^-^Ti 14L
TEMP RH.percent
~ ?.5//
Draw /Vo/-?/? Arrow
7XACXS /^-^
z^v/;
)£m/ss/on Point
/t&H
Observers Position
^^^ „ «AC£
x^
Sun Location L/ne~\^
COMMENTS
;ses ^ o/£
I HA VE RECEIVED A COPY OF THESE OPACITY OBSERVA TIONS
SIGNATURE /t^JMtO^\ tf 0T5
OBSERVATION DATE
AWV\
7
2
3
4
5
6
7
' 8
9
70
7 7
72
73
74
75
76
77
78
79
20
27
22
23
24
25
26
27
28
29
30
0
30
55
35
30
30
35
50
35
60
50
30
30
75
35
50
35
35
55
66
30
-30
30
-
A VER A GE OP A CITY FOR /
HIGHEST PERIOD ^O°/O
\S£C
37
32
33
34
35
35
37
3fi
39
40
41
42
43
44
45
46
47
48
49
50
0
57
52 I
"53 t ~
54
55
56
57
58
59
60
STOP TIME
75
30
45
NUMBER OF READINGS ABOVE
*YO % WERE //
RANGE OF OPACITY READINGS -f //"SO/
MINIMUM 3O%) MAXIMUM foU /Q
OBSERVER'S NAME f PR I NT)
V£- PKOFFIT
OBSERVER'S SIGNATURE
•^ ^, ~fcl4ff&3
DATE
id \ t i / */ ^ )
/O CX ^ ^™ 1 OAw
ORGANIZA TION *. .- ,-.
3T"ATG Al£P<%£VTfOrJ CblJT&>L o^ACD
CERTIFIED BY .<-f^
E"ASTEJ?f\| TECHAJfCAZ- ASSOv-.
VERIFIED BY
DT* MM n&
DATE
Figure 6.1. Visible emission observation form
-------
April 1983
Section 3.12.6
Visible Emission Summary Data Sheet
Company
Start time
.Location
Emission point
Start
no
1
2
3
4
5
6
7
a
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
Total
opacity
055'
80^"
Q df}
Dcx^'
$(,0
gyo
ffL^J /I)
Average
opacity
w -a
,?£•£
%,(?
2S.®
2>£.O
35^.2-
Start
no
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
Total
opacity
Average
opacity
Start
no
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
704
705
706
707
108
Total
opacity
Average
opacity
Start
no
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
Total
opacity
A verage
opacity
Start
no
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
Total
opacity
A verage
opacity
Start
no
181
182
183
184
J85
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
Total
opacity
A verage
opacity
Maximum average 3 B? pingaverage_s in excess of standard
r.almilated hy \/-£] PfrfiFFfr7~ T
Figure 6.2. Visible emission summary data sheet
of six
__»2_
minute average
Listing start number of these averages
Date '
/ ' '•$
-------
Section 3.12.6
April 1983
VISIBLE EMISSION OBSERVATION FORM
SOURCE NAME
ADDRESS
CITY
PHONE
STATE
ZIP
SOURCE ID NUMBER
PROCESS EQUIPMENT
CONTROL EQUIPMENT
OPERA TING MODE
OPERA TING MODE
DESCRIBE EMISSION POINT
START STOP
HEIGHT ABOVE GROUND LEVEL
START STOP
DISTANCE FROM OBSERVER
START STOP
HEIGHT
START
RELATIVE TO OBSERVER
STOP
DIRECTION FROM OBSERVER
START STOP
DESCRIBE EMISSIONS
START STOP
EMISSION COLOR
START STOP
WA TER DROPLETS PRESENT
NO O YESD
PLUME
FUG/T/V
TYPE CONTINUOUS D
£ D INTERMITTENT D
IF WA TER DROPLET PLUME
ATT A CHED D DETA CHED D
POINT IN THE PLUME A T WHICH OPACITY WAS DETERMINED
START STOP
DESCRIBE BACKGROUND
START STOP
BACKGROUND COLOR
START STOP
WIND SPEED
START STOP
AMBIENT TEMP
START STOP
Source Layout Sketch
X
Sun~d}- Wind ^
Plume and — ^^
Stack ^-""""^
^ '4
SKY CONDITIONS
START STOP
WIND DIRECTION
START
STOP
WET BULB TEMP RH. percent
Draw North Arrow
n
V_y
Emission Point
Observers Posit/on
?^\^
Sun Location Line
COMMENTS
1 HA VE RECEIVED A COPY OF THESE OPACITY OBSERVA TIONS
S/GNA TUBE
TITLE
DATE
OBSERVATION DATE
\SEC
MIN\
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
0
1
5
9
13
17
21
25
29
33
37
41
45
49
53
57
61
65
69
73
77
81
85
89
93
97
101
105
109
113
117
15
2
6
10
14
18
22
26
30
34
38
42
46
50
54
58
62
66
70
74
78
82
86
90
94
30
3
7
11
15
19
23
27
31
35
39
43
47
51
55
59
63
67
71
75
79
83
87
91
95
98 '. 99
102
106
110
114
118
103
107
11 1
115
119
START TIME
45
4
8
12
16
20
24
28
32
36
40
44
48
52
56
60
64
68
72
76
80
84
88
92
96
100
104
108
112
116
120
A VERAGE OPACITY FOR
HIGHEST PERIOD
\SEC
Mlfr\
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
0
121
125
129
133
137
141
145
149
153
157
161
165
169
173
177
181
185
189
193
197
201
205
209
213
217
221
225
229
233
237
STOP TIME
15
122
126
130
134
138
142
146
150
154
158
162
166
170
174
178
182
186
190
194
198
202
206
210
214
218
222
226
230
234
238
30
123
127
131
135
139
143
147
151
155
159
163
167
171
175
179
183
187
191
195
199
203
207
211
215
219
223
227
231
235
239
45
124
128
132
136
140
144
148
152
156
160
164
168
172
176
180
184
188
192
196
200
204
208
212
216
220
224
228
232
236
240
NUMBER OF READINGS ABOVE
% WERE
RANGE OF OPACITY READINGS
MINIMUM MAX/MUM
OBSERVER'S NAME (PRINT)
OBSERVER'S S/GNA TURE
DATE
ORGANIZA T/ON
CERTIFIED BY
VERIFIED BY
DATE
DATE
Figure 6.3. Opacity data form with start numbers shown
-------
April 1983
Section 3.12.6
30
20
§
10
Time, minutes
Figure 6.4. Plot opacity versus time
acknowledged and the individual data
values may be adjusted
mathematically in the final data report
to show the increase m opacity
reading due to the added path length
These adjusted opacity readings
should be used in determining
averages in excess of the standard
The calculation of observed path
length is shown in Appendix A of
Reference 1 and is included here for
the observer's convenience Figure
6 5 shows how the slant angle vanes
with distance from an elevated
source. As an observer moves closer
to the base of the stack, the angle of
sight and the path length through the
plume both increase; this causes the
observed opacity to increase even
though the cross-plume opacity
remains constant This situation only
applies when the opacity is read
through a vertically rising plume and
the observer is on the same plane as
the base of the stack
The actual opacity may be
calculated from the observed opacity,
if the slant angle 8 is known, or from
the known height of the stack and the
distance from the observer to the base
of the stack.
Method 1 (when slant angle 8 is known)
1 -( Op ) =T0Equation 6-1
100
(1 -T")x 100 -Or.
where
00= observed opacity in %
T0= observed transmittance
F= cosine of 8
Oc= corrected opacity in %.
Method 2 (where distances are known)
Y
F = ./H2 + Y~ Equation 6-2
1-< °J> ) = T0
100
(1 -T^)x 100 = OC
where
00= observed opacity in %
T0= observed transmittance
F= cosine of 8
Oc= corrected opacity in %
H= height of stack
Y= distance of observer from stack.
Note' Since the correction is a
power function, the correction must
be made on each opacity reading and
the corrected values used for
calculations, in lieu of the correction
being conducted on the reduced
(averaged) data
Table 6 1 presents the opacity
corrected for slant angle or viewing
angle 6 versus the full range of
opacity readings. For angles less than
approximately 18° the adjustment is
relatively insignificant.
6.3 Predicting Steam Plume
Formation
The psychrometric chart can be
used in conjunction with a simple
/
4ff
length through Plume
9 - Slant Angle
Stack
H
3H\
Figure 6.5. Variation of observation angle and pathlength with distance from an elevated source
-------
Section 3.12.6
April 1983
Table 6. 1 . Opacity Correction for Slant Angle
Measured
opacity. Slant angle 6, degrees
% 0 10 20
95 95 95 94
90 90 90 89
85 85 85 83
80 80 80 78
75 75 75 73
70 70 70 68
65 65 64 63
60 60 59 58
55 55 55 53
50 50 50 48
45 45 45 43
40 40 40 38
35 35 35 33
30 30 30 29
25 25 25 24
20 20 -20 19
15 15 15 14
10 10 10 9
5 554
0 000
equation to predict the formation of a
visible water vapor (steam) plume. The
psychrometric chart is a graphical
representation of the solutions of
various equations of the state of air
and water vapor mixtures (see Figure
6 6) Both the ambient and stack
emission data points on the chart are
referred to as their "state point" and
represent one unique combination of
the following five atmospheric
nronertifis
30 40 50 60
93 90 85 78
86 83 77 68
81 77 71 62
75 71 65 55
70 65 59 50
65 60 54 45
60 55 49 41
55 50 45 37
50 46 40 33
45 41 36 29
40 37 32 26
36 32 28 23
31 28 24 19
27 24 21 16
22 20 17 13
18 16 13 11
13 12 10 8
9875
4333
0000
represented by the set of curved lines
originating in the lower left portion of
the chart.
Absolute humidity (humidity ratio) -
The mass of water vapor per unit
mass of air, expressed as grams per
pound or pound per pound;
represented by the vertical axes.
Specific volume - The volume
occupied by a unit mass of air,
expressed as cubic feet per pound;
determines the values for the
remaining three properties. For
example, by using a sling
psychrometer to measure the wet and
dry bulb temperatures, one can
determine the relative humidity, the
absolute humidity, and the specific
volume of the air.
To predict the occurrence of a
visible steam plume, both the ambient
air conditions and the stack gas
conditions must be known or
calculated and located on the
psychrometric chart. If any portion of
the line connecting the two points lies
to the left of the 100 percent relative
humidity line, it is an indication that
the change of the exhaust gas from
the stack state conditions to the
ambient air state will be accompanied
by the condensation of the water
vapor present in the exhaust stream
and a resultant visible steam plume.
Obtaining the state point for the
ambient air conditions is relatively
simple, as previously indicated, the
wet and dry bulb temperatures, which
will determine a unique state point,
can be measured by using a sling
psychrometer. Often the only data
available for determining the state
point of the stack gas are the dry bulb
temperature of the exhaust gas
stream and its moisture content.*
However, a relationship exists
between the moisture content and the
humidity ratio (or absolute humidity),
as shown in the following equation:
Dry bulb temperature - The actual
ambient temperature; represented by
the horizontal axis
Wet bulb temperature - The
temperature indicated by a "wet bulb"
thermometer ( a regular thermometer
that has its bulb covered with a wet
wick and exposed to a moving air
stream); represented by the curved
axis on the left side of the chart
(saturation temperature)
Relative humidity - The ratio of the
partial pressure of the water vapor to
the vapor pressure of water at the
same temperature; values are
represented by the diagonal lines
running from lower right to upper left.
The relationships shown in the chart
differ with changes in barometric
pressure. The chart included in this
section is for a barometric pressure of
29.92 inches of mercury. Therefore,
with use of wet bulb dry bulb
technique, if the actual pressure is
less than about 29.5 inches of
mercury, the humidity ratio should be
calculated from the equation and not
the chart.
Plotting the values for any two of
the five atmospheric properties
Table 6.2. Vapor Pressures of Water at Saturation
Temp ,
°F
30
40
50
60
70
80
90
100
110
720
730
0
0 1647
02478
03626
05218
0. 7392
1 032
7 422
1.932
2596
3446
4525
7
0.1716
0.2576
03764
05407
07648
1 066
1 467
7 332
2672
3 543
4647
2
0 1803
02677
03906
05601
07912
1 102
1 513
2052
2749
3 642
4772
Water
3
0 1878
02783
0.4052
05802
08183
1.138
1 561
2 114
2.829
3.744
4.900
vapor pressure, in. Hg
4
0 1955
02891
04203
06009
08462
1 175
7 670
2 178
2911
3848
5031
5
O 2035
03004
04359
06222
08750
1 213
1 660
2243
2995
3954
5 165
6
02118
03120
0.4520
06442
09046
1 253
1.712
2310
3081
4063
5302
7
0.2203
03240
04586
0.6669
09352
1 293
1.765
2379
3 169
4.174
5.442
8
0.2292
03364
04858
0.6903
09666
1 335
1 819
2449
3259
4.289
5 585
B
0.2383
03493
0.5035
0 7144
09989
1.378
1 875
2.521
3351
4.406
5.732
where
HR = humidity ratio, in pound of water
vapor per pound of dry air
MC = %_ moisture content, expressed
100
as a decimal.
The following sample problem
demonstrates the use of this
equation
Given.'
Ambient conditions
Dry bulb temperature = 70°F
Wet bulb temperature = 60°F
Barometric pressure = 29.92 in. Hg
Effluent gas conditions
Dry bulb temperature = 160°F
Moisture content = 16.8% = 0.168
100
Find.
Ambient relative humidity
Exhaust gas humidity ratio
Determine whether or not
condensed water (steam plume)
will form
"These are usually obtained from plant records
or are estimated from recent source test data
-------
April 1983
Section 3.12.6
Solution:
Plot ambient wet bulb and dry bulb
temperatures (see Figure 6.5).
Ambient relative humidity = 55%
Exhaust gas humidity ratio = HR
HR=0.62(MC)
1 - MC
=0.62 (0 1 68)
1 - 0.168
= 0 125 Ib/lbdry air
Plot humidity ratio and stack dry bulb
temperature (see Figure 6 6) Connect
the ambient state point and stack gas
state point with a straight line (see
Figure 6.5). The line crosses the 100
percent relative humidity line, thus,
formation of a visible water vapor
plume is probable.
When the wet bulb/dry bulb
technique is used and the barometric
pressure is less than 29.5 m. Hg, it is
suggested that Equation 6-5 be used
to calculate the moisture content
(MC).
Equation 6-5
where
VP = Vapor pressure of H20 using
Equation 6-6
Pabs = Barometric pressure
VP = SVP - (3 57x10~4) (Pabs) (Td-Tw)
(1 +TW - 32)
1571 Equation 6-6
where
SVP = Saturated vapor pressure in in
Hg at wet bulb temperature
(taken from Table 6.2)
la = Temperature of dry bulb
thermometer, °F
Tw = Temperature of wet bulb
thermometer, °F
Table6.3 Activity Matrix for Calculations
Acceptance
Calculation limits
Average opacity Data in Fig 6.1
completed and
checked to with-
in roundoff error
Running average Data in Fig 6.2
Frequency and
method of
measurement
For each com-
pliance test,
perform inde-
pendent check
of data form and
calculations
As above
Action if
requirements
are not met
Complete the
data and initial
any changes in
calculations
As above
opacity
Path length through
the plume
Predicting steam
plume
completed and
checked
No limits have
been set
No limits have
been set
For each com-
pliance test with
the slant angle
>J8°, calculate
using Eq. 6-1
Use psychro-
metnc chart and
Equation 6-3
Perform calcu-
lations
Perform calcu-
lations
-0 14
_ Psychrometr/c Chart
Barometric Pressure 29 92 Inches of Mer
60
80
100 120 140 160 180 200 220 240 260 280 300
320
- State Point for Ambient Conditions
- State Point for Stack Gas Conditions
Dry Bulb Temperature, °F
Figure 66 Psychrometric chart for problem solution
-------
April 1983
Section 3.12.7
An audit is an independent
assessment of data quality
Independence is achieved by using
observers and data analysts other
than the original observer/analyst
Routine QA checks for proper
observer positioning and
documentation are necessary to
obtain good quality data. Table 7.1 at
the end of this section summarizes
the QA activities for auditing
Two performance audits are
recommended for VE readings
1. Audit of observer by having an
experienced observer make
independent readings
2. Audit of data forms and
calculations
In addition, it is recommended that a
systems audit be conducted by an
experienced observer at the same
time the performance audit of visible
emissions is conducted. The two
performance audits are described in
Subsection 7 1 and the systems audit
is described in Subsection 7 2
7.1 Performance Audits
Performance audits are quantitative
evaluations of the quality of visible
emission data.
7.1.1 Performance Audit of Visible
Emissions - In this audit, an
experienced observer goes with the
observer being audited and both
observers take the readings
simulataneously (using the same time
piece) and complete the data forms as
independently as is practical The
audit is intended for observers in their
first year and observers who have not
made opacity observation in the field
in over a year The differences
between the two readings serve as a
measure of accuracy assuming the
experienced observer reads the "true
opacity " Because this assumption is
not necessarily correct, the difference
between the two readings is a
combined measure of accuracy of
both observers For a minimum of six
minutes (24 readings), the average of
the absolute differences should be less
than 10 percent, and no individual
differences should exceed 20 percent
(The values of 10% and 20%
suggested for the limits are the
approximate results of combining the
allowable errors of the two observers,
eg ,V(7.5)2 + (7 5)2 = 10 6%, and
V152 + 152 = 21 2% This audit should
be performed twice in a year for the
7.0 Auditing Procedures
first year of an observer and
whenever conditions tend to warrant
them thereafter Calculate %A using
Equation 7-1.
%A = |VE (observer) - VE (auditor)]
Equation 7-1
where
VE (observer) = average and in-
dividual VE
readmg(s) of the
observer being
audited
VE (auditor) = average and
individual VE
readmg(s) of the
auditor
7.1.2 Performance Audit of Data
Calculations - This audit is an
independent check of all calculations
performed for the summary VE report
Every calculation should be checked
within round-off error This audit
should be conducted on at least 7
percent of the annual numbers of VE
summary reports.
7.2 System Audit
A system audit provides an on-site
qualitative inspection and review of
the total inspection. This audit
includes a check of the "Record of
Visual Determination of Opacity,"
Figure 9 1 of Section 3128, and the
top portion of the "Observation
Table 7.1. Activity Matrix for Auditing Procedures
Record," Figure 9.2 of Section 3.12.8.
In addition, the auditor should assess
the visible emission inspection
technique used by the auditee. This
portion of the system audit is best
handled in conjunction with the
performance audit described in the
previous Subsection 711. Therefore,
the frequency of the system audit
should coincide with the frequency of
the performance audits of visible
emissions. Some observations to be
made by the auditor are listed in
Figure 7 1
Audit
Performance audit
of visible emissions
Performance audit
of data calculations
System audit
Acceptance
limits
Individual obser-
vations within
±20%, average
(absolute) devia-
tion within
±10%
Original and
check calcula-
tions agree
within round-off
error
Conduct obser-
vations as de-
scribed in this
section of
the Handbook
Frequency and
method of
measurement
At least two
times during the
first year; sim-
ultaneous ob-
servation and
data recording
Seven percent
of tests for
compliance, per-
form indepen-
dent check on
all calculations
At least two
times during the
first year; use
audit checklist
(Fig 7. 1)
Action if
requirements
are not met
Review obser-
vation tech-
niques
Check and cor-
rect all calcu-
lated results
(averages)
Explain to obser-
ver the devia-
tions from rec-
ommended
procedures;
note the devia-
tions on Fiq 7 1
-------
Section 3.12.7
April 1983
X? />/> /I I
Name of individualist audited J./UTJ fi, (^
//,.,i l/.^/^ <,
AHiliation _
Auditor name
Date of audit
77 f
• /Co •
_ A11 illation
£FA
- Auditor signature
Yes
/
I/
_fc^
X
_./
^L
i/
i/
(^
j^
^
S
-j£
/
_t/L
No
Comment
c.on-pioiertti<3/i\/ retftSirgd
/ /
A/A
/
f//A
/
Operation
/ Equipment satisfactory
2 Data forms completed
3 Post-notification /courtesy obligation! performed
4 Correct identification of point of emissions
5. Plume associated with process generation point
6 Credentials okay
7 Observer acted in professional and courteous manner
8 Proper observer position
9 Opacity readings complete
10 Ancillary measurements available
1 1 Camera used to validate sightings/ source identification
72 Facility personnel given a copy of raw data
13 Mutiple sources/ plumes /out lets
14 Lighting conditions satisfactory
15 Background conditions framing, etc ) satisfactory
16 Slant angle recorded
17 Fugitive emissions
18 Time of day recorded
19 Recertified within last 6 months
General comments:
%rform*«c<: fartof l/£ te^ys Mf* Jctydzile.
&»*&', /// ^/ ^^<5 /£ facias we /
-------
April 1983
Section 3.12.8
Method 9—Visual
Determination of the Opacity
of Emissions from Stationary
Sources
Many stationary sources discharge
visible emissions into the atmosphere;
these emissions are usually in the
shape of a plume This method
involves the determination of plume
opacity by qualified observers The
method includes procedures for the
training and certification of observers,
and procedures to be used in the field
for determination of plume opacity
The appearance of a plume as viewed
by an observer depends upon a
number of variables, some of which
may be controllable and some of
which may not be controllable in the
field Variables which can be
controlled to an extent to which they
no longer exert a significant influence
upon plume appearance include.
Angle of the observer with respect to
the plume, angle of the observer with
respect to the sun, point of
observation of attached and detached
steam plume, and angle of the
observer with respect to a plume
emitted from a rectangular stack with
a large length to width ratio The
method includes specific criteria
applicable to these variables
Other variables which may
not be controllable in the field are
luminescence and color contrast
between the plume and the
background against which the plume
is viewed These variables exert an
influence upon the appearance of a
plume as viewed by an observer, and
can affect the ability of the observer
to accurately assign opacity values to
the observed plume Studies of the
theory of plume opacity and field
studies have demonstrated that a
plume is most visible and presents the
greatest apparent opacity when
viewed against a contrasting
background It follows from this, and
is confirmed by field trials, that the
opacity of a plume, viewed under
conditions where a contrasting
background is present can be
assigned with the greatest degree of
accuracy However, the potential for a
positive error is also the greatest
when a plume is viewed under such
contrasting conditions Under
conditions presenting a less
contrasting background, the apparent
opacity of a plume is less and
8.0 Reference Method3
approaches zero as the color and
luminescence contrast decrease
toward zero As a result, significant
negative bias and negative errors can
be made when a plume is viewed
under less contrasting conditions. A
negative bias decreases rather than
increases the possibility that a plant
operator will be cited for a violation of
opacity standards due to observer
error
Studies have been undertaken to
determine the magnitude of positive
errors which can be made by qualified
observers while reading plumes under
contrasting conditions and using the
procedures set forth in this method.
The results of these studies (field
trials) which involve a total of 769
sets of 25 readings each are as
follows'
(1) For black plumes (133 sets at a
smoke generator). 100 percent
of the sets were read with a
positive error1 of less than 7 5
percent opacity, 99 percent
were read with a positive error
of less than 5 percent opacity.
(2) For white plumes (170 sets at a
smoke generator, 168 sets at a
coal-fired power plant, 298 sets
at a sulfunc acid plant), 99
percent of the sets were read
with a positive error of less than
7 5 percent opacity; 95 percent
were read with a positive error
of less than 5 percent opacity.
The positive observational error
associated with an average of twenty-
five readings is therefore established.
The accuracy of the method must be
taken into account when determining
possible violations of applicable
opacity standards.
1. Principle and applicability.
1.1 Principle The opacity of
emissions from stationary sources is
determined visually by a qualified
observer
1.2 Applicability. This method is
applicable for the determination of the
opacity of emissions from stationary
sources pursuant to § 60.11(b) and for
qualifying observers for visually
determining opacity of emissions.
'For a set, positive error = average opacity
determined by observers' 25 observations —
average opacity determined from
transmissometer's 25 recordings
2. Procedures.
The observer qualified in
accordance with paragraph 3 of this
method shall use the following
procedures for visually determining
the opacity of emissions:
2.1 Position. The qualified observer
shall stand at a distance sufficient to
provide a clear view of the emissions
with the sun oriented in the 140°
sector to his back Consistent with
maintaining the above requirement,
the observer shall, as much as
possible, make his observations from
a position such that his line of vision
is approximately perpendicular to the
plume direction, and when observing
opacity of emissions from rectangular
outlets (e.g. roof monitors, open
baghouses, noncircular stacks),
approximately perpendicular to the
longer axis of the outlet. The
observer's line of sight should not
include more than one plume at a
time when multiple stacks are
involved, and in any case the observer
should make his observations with his
line of sight perpendicular to the
longer axis of such a set of multiple
stacks (e.g. stub-stacks on
baghouses).
2.2 Field records. The observer
shall record the name of the plant,
emission location, type facility,
observer's name and affiliation, and
the date on a field data sheet (Figure
9-1). The time, estimated distance to
the emission location, approximate
wind direction, estimated wind speed,
description of the sky condition
(presence and color of clouds), and
plume background are recorded on a
field data sheet at the time opacity
readings are initiated and completed.
2.3 Observations. Opacity
observations shall be made at the point
of greatest opacity in that portion of
the plume where condensed water
vapor is not present. The observer
shall not look continuously at the
plume, but instead shall observe the
plume momentarily at 15-second
intervals.
2.3.7. Attached steam plumes. When
condensed water vapor is present
within the plume as it emerges from
the emission outlet, opacity
observations shall be made beyond the
point in the plume at which
-------
Section 3.12.8
April 1983
Company
Location
Test Number .
Date
Type Facility _
Control Device
Hours of Observation
Observer
Observer Certification Date
Observer Affiliation
Point of Emissions
Height of Discharge Point
Clock Time
Observer Location
Distance to Discharge
Direction from Discharge
Height of Observation Point
Background Description
Weather Conditions
Wind Direction
Wind Speed
Ambient Temperature
Sky Conditions /clear,
overcast, % clouds, etc )
Plume Description
Color
Distance Visible
Other Information
Initial
Final
Summary of A verage Opacity
Set
Number
Time
Start—End
Opacity
Sum
A verage
Readings ranged from to % opacity
The source was/was not in compliance with
at the time evaluation was made.
Figure 9.1 Record of Visual Determination of Opacity
Page
.of.
condensed water vapor is no longer
visible. The observer shall record the
approximate distance from the
emission outlet to the point in the
plume at which the observations are
made
2.3.2 Detached steam plume. When
water vapor in the plume condenses
and becomes visible at a distinct
distance from the emission outlet, the
opacity of emissions should be
evaluated at the emission outlet prior
to the condensation of water vapor
and the formation of the steam plume.
2.4 Recording observations. Opacity
observations shall be recorded to the
nearest 5 percent at 1 5-second
intervals on an observational record
sheet (See Figure 9-2 for an
example.) A minimum of 24
observations shall be recorded Each
momentary observation recorded shall
be deemed to represent the average
opacity of emissions for a 1 5-second
period.
2.5 Data Reduction Opacity shall be
determined as an average of 24
consecutive observations recorded at
15-second intervals. Divide the
observations recorded on the record
sheet into sets of 24 consecutive
observations. A set is composed of
any 24 consecutive observations. Sets
need not be consecutive in time and
in no case shall two sets overlap. For
each set of 24 observations, calculate
the average by summing the opacity
of the 24 observations and dividing
this sum by 24 If an applicable
-------
April 1983
Section 3.12.8
Company
Location
Test Number .
Date
Observer
Type Facility
Point of Emissions
Hr
Min.
0
1
2
3
4
5
6
7
5
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
Seconds
0
15
30
45
Steam Plume
(check if applicable)
Attached
Detached
Comments
Figure 9.2 Observation Record
(FR Doc 74-26150 Filed 11-11-74. 845 am)
Page of
-------
Section 3.12.8
April 1983
standard specifies an averaging time
requiring more than 24 observations,
calculate the average for all
observations made during the
specified time period. Record the
average opacity on a record sheet.
(See Figure 9-1 for an example.)
3. Qualifications and testing.
3.1 Certification requirements. To
receive certification as a qualified
observer, a candidate must be tested
and demonstrate the ability to assign
opacity readings in 5 percent
increments to 25 different black
plumes and 25 different white
plumes, with an error not to exceed
15 percent opacity on any one reading
and an average error not to exceed 7.5
percent opacity in each category.
Candidates shall be tested according to
the procedures described in paragraph
3.2. Smoke generators used pursuant
to paragraph 3.2 shall be equipped
with a smoke meter which meets the
requirements of paragraph 3.3.
The certification shall be valid for a
period of 6 months, at which time the
qualification procedure must be
repeated by any observer in order to
retain certification.
3.2 Certification procedure.
The certification test consists of
showing the candidate a complete run
of 50 plumes—25 black plumes and
25 white plumes—generated by a
smoke generator. Plumes within each
set of 25 black and 25 white runs
shall be presented in random order.
The candidate assigns an opacity
value to each plume and records his
observation on a suitable form. At the
completion of each run of 50
readings, the score of the candidate is
determined. If a candidate fails to
qualify, the complete run of 50
readings must be repeated in any
retest. The smoke test may be
administered as part of a smoke
school or training program, and may
be preceded by training or
familiarization runs of the smoke
generator during which candidates
are shown black and white plumes of
known opacity.
3.3 Smoke generator
specifications.
Any smoke generator used for the
purposes of paragraph 3.2 shall be
equipped with a smoke meter
installed to measure opacity across
the diameter of the smoke generator
stack. The smoke meter output shall
display instack opacity based upon a
path length equal to the stack exit
diameter, on a full 0 to 100 percent
chart recorder scale. The smoke meter
optical design and performance shall
meet the specifications shown in
Table 9-1. The smoke meter shall be
calibrated as prescribed in paragraph
3.3.1 prior to the conduct of each
smoke reading test. At the
completion of each test, the zero and
span drift shall be checked and if the
drift exceeds ±1 percent opacity, the
conditions shall be corrected prior to
conducting any subsequent test runs.
The smoke meter shall be
demonstrated, at the time of
installation, to meet the specifications
listed in Table 9-1. This demonstration
shall be repeated following any
subsequent repair or replacement of
the photocell or associated electronic
circuitry including the chart recorder
or output meter, or every 6 months,
whichever occurs first.
Table 9-1. Smoke Meter Design and
Performance Specifica-
tions
Parameter: Specification
a. Light source Incandescent lamp
operated at
nominal rated
voltage.
b. Spectral Photopic (daylight
response of spectral response of
photocell. the human eye—
reference 4.3).
c. Angle of view 15° maximum total
angle.
d. Angle of projec- 15° maximum total
tion angle.
e. Calibration error ±3% opacity, maxi-
mum
f. Zero and span ±1% opacity, 30
drift. minutes.
g. Response time <5 seconds.
3.3.1 Calibration. The smoke meter
is calibrated after allowing a minimum
of 30 minutes warmup by alternately
producing simulated opacity of 0
percent and 100 percent. When stable
response at 0 percent or 100 percent
is noted, the smoke meter is adjusted
to produce an output of 0 percent or
100 percent, as appropriate. This
calibration shall be repeated until
stable 0 percent and 100 percent
readings are produced without
adjustment. Simulated 0 percent and
100 percent opacity values may be
produced by alternately switching the
power to the light source on and off
while the smoke generator is not
producing smoke.
3.3.2 Smoke meter evaluation. The
smoke meter design and performance
are to be evaluated as follows:
3.3.2.1 Light source. Verify from
manufacturer's data and from voltage
measurements made at the lamp, as
installed, that the lamp is operated
within ±5 percent of the nominal
rated voltage.
3.3.2.2 Spectral response of
photocell. Verify from manufacturer's
data that the photocell has a photopic
response; i e., the spectral sensitivity
of the cell shall closely approximate
the standard spectral-luminosity curve
for photopic vision which is
referenced in (b) of Table 9-1.
3.3.2.3 Angle of view. Check
construction geometry to ensure that
the total angle of view of the smoke
plume, as seen by the photocell, does
not exceed 15°. The total angle of
view may be calculated from' 8 = 2
tan'1 d/2L, where 6 = total angle of
view; d = the sum of the photocell
diameter + the diameter of the limiting
aperture; and L = the distance from
the photocell to the limiting aperture.
The limiting aperture is the point in
the path between the photocell and
the smoke plume where the angle of
view is most restricted. In smoke
generator smoke meters this is
normally an orifice plate.
3.3.2.4 Angle of projection. Check
construction geometry to ensure that
the total angle of projection of the
lamp on the smoke plume does not
exceed 15°. The total angle of
projection may be calculated from: 6 =
2 tan"1 d/2L, where G - total angle of
projection; d = the sum of the length
of the lamp filament + the diameter of
the limiting aperture; and L = the
distance from the lamp to the limiting
aperture.
3.3.2.5 Calibration error Using
neutral-density filters of known
opacity, check the error between the
actual response and the theoretical
linear response of the smoke meter.
This check is accomplished by first
calibrating the smoke meter according
to 3 3.1 and then inserting a series of
three neutral-density filters of
nominal opacity of 20, 50, and 75
percent in the smoke meter
pathlength. Filters calibrated within
±2 percent shall be used. Care should
be taken when inserting the filters to
prevent stray light from affecting the
meter. Make a total of five
nonconsecutive readings for each
filter. The maximum error on any one
reading shall be 3 percent opacity.
3.3.2.6 Zero and span drift
Determine the zero and span drift by
calibrating and operating the smoke
-------
April 1983
Section 3.12.8
generator in a normal manner over a
1-hour period The drift is measured
by checking the zero and span at the
end of this period
3.3.2 7 Response time Determine
the response time by producing the
series of five simulated 0 percent and
100 percent opacity values and
observing the time required to reach
stable response. Opacity values of 0
percent and 100 percent may be
simulated by alternately switching the
power to the light source off and on
while the smoke generator is not
operating.
4. References.
4.1 Air Pollution Control District
Rules and Regulations, Los Angeles
County Air Pollution Control District,
Regulation IV, Prohibitions, Rule 50.
4.2 Weisburd, Melvm L Field
Operations and Enforcement Manual
for Air, U S. Environmental-Protection
Agency, Research Triangle Park, N C.,
APTD-1 100, August 1972, pp 4.1-
4.36.
4.3 Condon, E.U., and Odishaw, H.,
Handbook of Physics, McGraw-Hill
Co., NY, NY, 1958, Table 3.1, p. 6-
52.
-------
April 1983
Section 3.12.9
9.0 References and Bibliography
10.
11
Technical Assistance Document.
Quality Assurance Guideline for
Visible Emission Training
Programs, EPA-600/S4-83-011.
Federal Register. Volume 39,
No. 219, November 12, 1974.
Method 9 - Visual
Determination of the Opacity of
Emissions from Stationary
Sources (Appendix A).
Conner, W.D. Measurement of
Opacity by Transmissometer and
Smoke Readers. EPA
Memorandum Report 1974
Conner, W.D., and J.R
Hodkinson. Optical Properties
and Visual Effects of Smoke
Plumes. U S. Environmental
Protection Agency. Office of Air
Programs, Edison Electric
Institute, and Public Health
Service. 1967 AP-30
Coons, J D , et al. Development,
Calibration, and use of a Plume
Evaluation Training Unit JAPCA
15. 199-203, May 1965
Crider, W.L., and J.A Tash.
Status Report: Study of Vision
Obscuration by Nonblack
Plumes. JAPCA 14:161-165,
May 1 964.
U.S Environmental Protection
Agency. Evaluation of EPA
Smoke School Results. Emission
Standards and Engineering
Division, Office of Air Quality
Planning and Standards. October
9, 1974
Evaluation and Collaborative
Study of Method for Visual
Determination of Opacity of
Emissions from Stationary
Sources. EPA-650/4-75-009
Malmberg, K.B EPA Visible
Emission Inspection Procedures.
U.S. Environmental Protection
Agency, Washington, D.C.
August 1975
Osborne, M C., and M.R
Midgett Survey of
Transmissometer Used in
Conducting Visible Emissions
Training Courses. Environmental
Monitoring and Support
Laboratory, U.S Environmental
Protection Agency. March 1978
Rmgelmann, M. Method of
Estimating Smoke Produced by
Industrial Installations Rev
Technique, 268, June 1898.
1 2 Weir, A , Jr., D G. Jones, and
LT Paypay. Measurement of
Particle Size and Other Factors
Influencing Plume Opacity.
Paper presented at the
International Conference on
Environmental Sensing and
Assessment, Las Vegas, Nevada,
September 14-19, 1975
13. US Environmental Protection
Agency. APTI Course 439
Visible Emissions Evaluation.
Student Manual. EPA-450/3-
78-106, 1978
14 U.S. Environmental Protection
Agency. APTI Course 439
Visible Emissions Evaluation.
Instructor Manual. EPA-450/3-
78-105, 1978.
15 U.S. Environmental Protection
Agency Guidelines for
Evaluation of Visible Emissions
EPA-340/1-75-007, 1975
16. U.S. Environmental Protection
Agency. Screening Procedures
for Ambient Air Quality Data
EPA-450/2-78-037, July 1978.
17. Validation of Air Monitoring
Data. EPA-600/4-80-030, June
1980.
-------
April 1983 1 Section 3.12.10
10.0 Data Forms
Blank data forms are provided on
the following pages for the
convenience of the QA Handbook
user No documentation is given on
these forms because it would detract
from their usefulness. Also, the titles
are placed at the top of the figures, as
is customary for a data form. These
forms are not required format, but are
intended as guides for the
development of an organizations' own
program. To relate the form to the
text, a form number is also indicated
in the lower right-hand corner (e.g.,
Form M9-1.1, which implies that the
form is Figure 1.1. in Section 3.12.1
of the Method 9 Handbook) Any
future revisions of this form can be
documented by adding A, B, C (e g.,
1 1A, LIB). The data forms included
in this section are listed below.
Form Title
1.2 Sample Certification Test Form
2 1 Procurement Log
4.1 Visible Emission Observer's
Plant Entry Checklist
4.1 Visible Emission Observer's
Plant Entry Checklist (Reverse
Side)
4.2 Visible Emission Observation
Form
4.2 Visible Emission Observation
Form (Reverse Side)
5.1 Visible Emission Summary Data
Sheet
6.2 Visible Emission Summary Data
Sheet (same as Figure 5.1)
7 1 Method 9 Checklist for Auditors
-------
Section 3.12.10
April 1983
Affiliation
Course location
Date
Sample Certification Test Form
Name
Sunglasses
Run Number
Distance and direction to stack
Reading
number
1
2
3
4
5
6
7
8
9
10
77
12
13
14
15
16
17
18
19
20
21
22
23
24
25
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
5
5
0
0
0 5
0 5
0 5
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
15 20 25
20 25
25
25
15 20 25
15
15 20
15 20
15 20
15 20
15 20
15 20
15
25
25
25
25
20 25
15
15 20
15 20
15
15
20 25
25
25
20 25
20 25
15 20 25
15
15 20
15 20
20 25
25
25
15 20 25
15
15
15
15 20
15 20
20 25
20 25
20 25
25
25
Sky .
30 35
30 35
30 35
30 35
30
30
30
40 45
40 45
40 45
40 45
50 55
50 55
50 55
50 55
30 35 40 45 50 55
30 35
30 35
30 35
30 35
30 35
30 35
30 35
30 35
30 35
35
35
30
30
30 35
30 35
30 35
35
35
35
30 35
30 35
40 45
40 45
40 45
40 45
40 45
40 45
40 45
40 45
40 45
30 35 40 45
40
40
40
40
45
45
40
40
40 45
40 45
40 45
45
45
45
45
55
55
50
50
50 55
50 55
50 55
50 55
50 55
50 55
50
50
55
55
50 55
50 55
50 55
50
50
55
55
50 55
50 55
50 55
50 55
60 65
60 65
60 65
60 65
60 65
60 65
60 65
60 65
60 65
60 65
60
60
60
60
60
65
65
65
65
65
60 65
60 65
60 65
60 65
60 65
60 65
60 65
60 65
60 65
40 45 50 55 60 65
Wind
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
80 85
80 85
80 85
80 85
90 95
90 95
90 95
90 95
80 85 90 95
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
95
95
90
90
90 95
90 95
90 95
90 95
90 95
90 95
90 95
90 95
95
95
90
90
90 95
90 95
90 95
100
100
100
100
100
100
100
100
100
100
WO
100
100
100
100
100
100
100
100
100
Error
90 95
90 95
90 95
90 95
90 95
Dev/e
inn
inn
mo
mn
inn
ttmn
Reading
number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
77
18
19
20
21
22
23
24
25
Error
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
0 5
10
10
10
10
10
10
10
10
10
10
0 5 10
0 5 10
0 5 10
0 5 10
0 5 10
10
10
10
10
10
10
10
10
10
10
15
15
15
20
20
20
15 20
15 20
15 20
15 20
15 20
15 20
15 20
15 20
15 20
15 20
15 20
15 20
15 20
15 20
15 20
15 20
15 20
15 20
15 20
15 20
15 20
15 20
25
25
25
25
25
25
25
25
25
25
25
25
25
30
30
30
25 30
25 30
30
30
30
25 30
25 30
30
30
30
30
30
30
30
25 30
25 30
25 30
25 30
25 30
25 30
25 30
25 30
35
35
35
35
35
40
40
40
40
40
35
35
35 40
35 40
35 40
35 40
35 40
35 40
35 40
35 40
35 40
35 40
35 40
35 40
35 40
35 40
35 40
35 40
35 40
35 40
45
45
45
45
45
40 45
40 45
45
45
45
45
45
45
45
45
45
45
45
45
45
45
45
45
45
45
50 55
50 55
50 55
50
50
50
50
50
50
50
50
55
55
55
55
55
50 55
50 55
50 55
50 55
50 55
50 55
55
55
55
50 55
50 55
50 55
50 55
50 55
50 55
50 55
60 65
60 65
60 65
60 65
60 65
60 65
60 65
60 65
60
60
65
65
60 65
60 65
60 65
60 65
50 55 60 65
65
65
60
60
60 65
60 65
60 65
60 65
60 65
60 65
60 65
60 65
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
70
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
75
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80
80
80
80
80
85
85
85
85
85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
80 85
90 95
90 95
90 95
90 95
90 95
90 95
90 95
90 95
90 95
90 95
90 95
90 95
90 95
90 95
90 95
90 95
90 95
90 95
90 95
80 85 90 95
90 95
90 95
90 95
90 95
90 95
100
100
100
100
100
100
100
100
100
100
WO
100
WO
100
100
100
100
100
wo
100
wo
100
wo
100
100
Deviation _
Quality Assurance Handbook M9-1 2
-------
April 1983
Section 3.12.10
Procurement Log
Item description
Quantity
Purchase
order
number
Vendor
Date
Ordered
Received
Cost
Disposition
Comments
Quality Assurance Handbook M9-2 1
-------
Section 3.12.10
April 1983
Visible Emission Observer's Plant Entry Checklist
Source name and address
Observer
Agency
Date of VE observation
Previous company contact (if applicable)
Title
Purpose of visit
Emission points at which VE observations to be conducted
Authority for entry (see reverse side)
Plant safety requirements
D Hardhat
D Safety glasses
D Side shields (on glasses)
D Goggles
D Hearing protection
Specify
D Coveralls
D Dust mask suggested
D Respirator(s)
Specify
D Safety shoes (steel-toed)
D Insulated shoes
D Gloves
D Other
D Specify
Company official contacted {on this visit)
Title
Quality Assurance Handbook M9-4 1
-------
April 1983 5 Section 3.12.10
Visible Emission Observer's Plant Checklist (Continued)
Authority for Plant Entry: Clean Air Act, Section 114
(a)(2) the Administrator or his authorized representative upon presentation of his credentials -
(A) shall have a right of entry to, upon or through any premises of such person or in which any records required to be
maintained under paragraph (1 j of this section are located, and
(B) may at reasonable times have access to, and copy of any records, inspect any monitoring equipment or methods
required under paragraph (1), and sample any emissions which such person is required to sample under
paragraph (1).
(b) (1) Each State may develop and submit to the A dministrator a procedure for carrying out this section in such State If the
Administrator finds the State procedure is adequate, he may delegate to such State any authority he has to carry out this
section.
(2) Nothing in this subsection shall prohibit the Administrator from carrying out this section in a State.
(c)Any records, reports or information obtained under subsection (aj shall be available to the public except that upon a showing
satisfactory to the Administrator by any person that records, reports, or information, or particular part thereof, (other than
emission data) to which the A dministrator has access under this section if made public would divulge methods or processes
entitled to protection as trade secrets of such person, the A dministrator shall consider such record, report, or information or
particular portion thereof confidential in accordance with the purposes of Section 1905 of Title 18 of the United States
concerned with carrying out this Act or when relevant in any proceeding under this Act."
Confidential Information: Clean Air Act, Section 114 (see above) 41 Federal Register 36902, September 1, 1976
If you believe that any of the information required to be submitted pursuant to this request is entitled to be treated as
confident/a/, you may assert a claim of business confidentiality, covering all or any part of the information, by placing on (or
attaching to) the information a cover sheet, stamped or typed legend, or other suitable notice, employing language such as
"trade secret," 'proprietary," or "company confidential." Allegedly confidential portions of otherwise nonconfidential
information should be clearly identified If you desire confidential treatment only until the occurrence of a certain event; the
notice should so state Information so covered by a claim will be disclosed by EPA only to the extent, and through the procedures,
set forth at 40 CFR, Part 2, Subpart B (41 Federal Register 36902, September 1, 1976.)
If no confidentiality claim accompanies this information when it is received by EPA, it may be made available to the public by
EPA without further notice to you
Quality Assurance Handbook M9-4.1
-------
Section 3.12.10
April 1983
Visible Emission Observation Form
SOURCE NAME
ADDRESS
CITY
PHONE
STATE
ZIP
SOURCE ID NUMBER
PROCESS EQUIPMENT
CONTROL EQUIPMENT
OPERA TING MODE
OPERA TING MODE
DESCRIBE EMISSION POINT
START STOP
HEIGHT ABOVE GROUND LEVEL
START STOP
DISTANCE FROM OBSERVER
START STOP
HEIGHT RELATIVE TO OBSERVER
START STOP
DIRECT/ON FROM
OBSERVER
START STOP
DESCRIBE EMISSIONS
START STOP
EMISSION COLOR
START STOP
WA TER DROPLETS PRESENT
NO D YESO
PLUME TYPE CONTINUOUS D
FUGITIVE D INTERMITTENT D
IF WA TER DROPLET PLUME
ATTACHED^ DETACHED D
POINT IN THE PLUME A T WHICH OPACITY WAS DETERMINED
START STOP
DESCRIBE BACKGROUND
START STOP
BACKGROUND COLOR
START STOP
WIND SPEED
START STOP
AMBIENT TEMP
START STOP
Source Layout Sketch
X
Sun-fy- W/nd_±
Plume and ^ ]^
Stack ^
^^^^ 140
SKY CONDITIONS
START STOP
WIND DIRECTION
START STOP
WET BULB TEMP
RH, percent
Draw North Arrow
o
Emission Point
Observers Position
>^^.
Sun Location Line
COMMENTS
I HAVE RECEIVED A COPY OF THESE OPACITY OBSERVATIONS
S/GNA TURE
TITLE
DATE
OBSERVATION DATE
\SEC
MIN\,
}
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
0
15
30
START TIME
45
A VERAGE OPACITY FOR
HIGHEST PERIOD
NSfC
Mlfr\
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
0
STOP TIME
15
30
45
NUMBER OF READINGS ABOVE
% WERE
RANGE OF OPACITY READINGS
MINIMUM MAXIMUM
OBSERVER'S NAME 1 'PRINT)
OBSERVER'S SIGN A TURE
DATE
ORGANIZATION
CERT/FIEDBY
VERIFIED BY
DATE
DATE
Quality Assurance Handbook M9-4.2
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April 1983
Section 3.12.10
Visible Emission Observation Form
This form is designed to be used in conjunction with EPA Method 9, "Visual Determination of the Opacity of Emissions from Stationary
Sources "Any deviations, unusual conditions, circumstances, difficulties, etc., not dealt with elsewhere on the form should be fully noted
in the section provided for comments Following are brief descriptions of the type of information that needs to be entered on the form; for a
more detailed discussion of each part of the form, refer to the "User's Guide to the Visible Emission Observation Form "
'Source Name - full company name, parent company or division
information, if necessary.
*Sky Conditions - indicate cloud cover by percentage or by
description (clear, scattered, broken, overcast, and color ofclouds)
"Address - street (not mailing) address or physical location
of facility where VE observation is being made
Phone - self-explanatory
Source ID Number - number from NEDS, CDS, agency file, etc
" Process Equipment, Operating Mode - brief description of process
equipment (include ID no.J and operating rate, % capacity utilization,
and/or mode (e g, charging, tapping}
"Control Equipment, Operating Mode - specify control device typefs)
and % utilization, control efficiency
''Describe Emission Point - stack or emission point location, geometry,
diameter, color, for identification.purposes
"Height Above Ground Level - stack or emission point height, from
files or engineering drawings
"Height Relative to Observer - indicate vertical posit/on of observation
point relative to stack top
"Distance From Observer - distance to stack +10%. to determine, use
rangefinder or map
"Direction From Observer - direction to stack, use compass or map,
be accurate to eight points of compass
"Describe Emissions - include plume behavior and other physical
characteristics (e g, looping, lacy, condensing, fumigating, secondary
particle formation, distance plume visible, etc)
"Emission Color - gray, brown, white, red, black, etc
Plume Type:
Continuous - opacity cycle >6 minutes
Fugitive - no specifically designed outlet
Intermittent - opacity cycle <6 minutes
" " Water Droplets Present - determine by observation or use wet sling
psychrometer. water droplet plumes are very white, opaque, and
billowy in appearance, and usually dissipate rapidly
""If Water Droplet Plume.
Attached - forms prior to exiting stack
Detached - forms after exiting stack
""Point in the Plume at Which Opacity was Determined - describe
physical location in plume where readings were made (e g ,4 in above
stack exit or 10 ft after dissipation of water plume I
"Describe Background - object plume is read against, include
atmospheric conditions (e g, hazy}
"Background Color - blue, white, new leaf green, etc
"Windspeed - use Beaufort wind scale or hand-held anomometer;
be accurate to ±5 mph
" Wind Direction - direction wind is from: use compass; be
accurate to eight points.
"Ambient Temperature - in °F or °C.
""Wet Bulb Temperature - the wet bulb temperature from the
sling psychrometer
""Relative Humidity - use sling psychrometer; use local U.S
Weather Bureau only if nearby
"Source Layout Sketch - include wind direction, associated
stacks, roads, and other landmarks to fully identify location of
emission point and observer position
Draw North Arrow • point line of sight in direction of emission
point, place compass beside circle, and draw in arrow parallel
to compass needle
Sun Location Line - point line of sight in direction of emission
point, place pen upright on sun location line, and mark location
of sun when pen's shadow crosses the observers position
""Comments - factual implications, deviations, altercations,
and/or problems not addressed elsewhere
Acknowledgment - signature, title, and date of company official
acknowledging receipt of a copy of VE observation form
"Observation Date - date observations conducted
"Start Time, Stop Time - beginning and end times of observation
period (e g. 1635 or 4 35 p m)
"Data Set - percent opacity to nearest 5%. enter from left to right
starting in left column
"Average Opacity for Highest Period - average of highest 24
consecutive opacity readings
Number of Readings Above (Frequency Count) count of total
number of readings above a designated opacity
"Range of Opacity Readings:
Minimum - lowest reading
Max/mum - highest reading
"Observer's Name - print in full
Observer's Signature, Date - sign and date after performing final
calculations
•Required by Reference Method 9, other items
suggested
"Required by Method 9 only when particular
factor could affect the reading
"Organization - observer's employer
"Certifier, Date - name of "smoke school" certifying observer and
date of most recent certification
Verifier, Date - signature of person responsible for verifying
observer's calculations and date of verification
Quality Assurance Handbook M 9-4.2
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Section 3.12.10
April 1983
Visible Emission Summary Data Sheet
Company .
Start time
. Date
. Location __
Emission point
Start
no
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
Total
opacity
Average
opacity
Start
no
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
Total
opacity
Average
opacity
Start
no
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
Total
opacity
A verage
opacity
Start
no
109
no
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
Total
opacity
A verage
opacity
Start
no
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
Total
opacity
A verage
opacity
Start
no
181
182
183
184
J85
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
Total
opacity
Average
opacity
Maximum average
Number of nonoverlappmg averages
Calculated by
% Stan number
in excess of standard .
Date _
of six minute average /
Listing start number of these averages
Reviewed by Date
Quality Assurance Handbook M9-5.1
and M9-6.2
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April 1983
Section 3.12.10
Method 9 Checklist for Auditors
Name of individuals) audited
Affiliation
Auditor name .
Date of audit _
.Affiliation
. A uditor signature
Yes
No
Comment
Operation
1 Equipment satisfactory
2 Data forms completed
3 Post-notification /courtesy obligation) performed
4 Correct identification of point of emissions
5 Plume associated with process generation point
6 Credentials okay
7 Observer acted in professional and courteous manner
8 Proper observer position
9 Opacity readings complete
10 Ancillary measurements available
1 1 Camera used to validate sightings/ source identification
12 Facility personnel given a copy of raw data
13 Mutiple sources/ plumes/ outlets
14 Lighting conditions satisfactory
15 Background conditions (raining, etc ) satisfactory
16 Slant angle recorded
1 7 Fugitive emissions
18 Time of day recorded
19 Recertified within last 6 months
General comments:
duality Assurance Handbook M9-7 1
'U.S. Government Priming Office: 1991— 548-187/40519
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