GUIDELINES FOR DETERMINING
CAPTURE EFFICIENCY
January 9, 1994
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GUIDELINES FOR DETERMINING
CAPTURE EFFICIENCY
Candace Sorrell
Source Characterization Group A (MD-19)
Emission Monitoring and Analysis Division
Office of Air Quality Planning and Standards
U. S. Environmental Protection Agency
Research Triangle Park, NC 27711
January 9, 1994
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TABLE OF CONTENTS
1.0 INTRODUCTION 1
1.1 Purpose 1
1.2 Background 1
1.3 Document Organization 2
2.0 RECOMMENDED CAPTURE EFFICIENCY (CE) PROTOCOLS AND
TEST METHODS 2
2.1 Permanent Total Enclosure 6
2.2 Temporary Total Enclosure 7
2.3 Building Enclosure 8
3.0 REQUIREMENTS FOR ALTERNATIVE CE PROTOCOLS ..... 9
3.1 Data Quality Objective 10
3.2 Lower Confidence Limit Approach 14
3.3 Additional Criteria 18
3.4 Reporting Requirements for Alternative
CE Protocols 20
3.5 Recordkeeping Requirements for Alternative
CE Protocols 21
4.0 MULTIPLE LINE TESTING 21
i 4.1 Aggregate Sampling „ 21
i 4.2 Multiple Lines/Common Control Device 21
5.0 REFERENCES 22
APPENDIX
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1.0 INTRODUCTION
l.l Purpose
The primary purpose of this document is to provide technical
guidance to U. S. Environmental Protection Agency (EPA) Regional
Offices regarding capture efficiency (CE) testing. The document
may also prove useful to State and local agency personnel and
owners and operators of stationary sources required to determine
CE.
l. 2 Background
In April 1990, EPA issued new guidance on CE testing.1 This
guidance replaced the traditional liquid/gas mass balance
determinations, which had often resulted in very poor precision
and CE values well in excess of 100 percent. The new protocols
involved permanent total enclosures (PTE's), temporary total
enclosures (TTE's), and building enclosures (BE's). This
guidance was later codified as part of the Chicago Federal
implementation plan (FIP) and included in the document "Model
Volatile Organic Compound Rules for Reasonably Available Control
Technology."2'3
In the beginning, the new protocols were met with resistance
from the regulated community, primarily on grounds of safety and
i
expense. Over time, the safety issue has largely been dispelled
as it has become clear that, with proper design and operation,
PTE's and TTE's pose minimal risk. However, it has also become
clear that in some cases, the new CE protocols are more costly
than the traditional liquid/gas procedures.
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To address the cost issue, EPA temporarily suspended certain
federal applicability aspects of its guidance while it embarked
on a 12-month study of alternatives with potential for reducing
CE testing costs. This document is a result of that study and of
simultaneous studies voluntarily undertaken by industry groups.
In this document, EPA presents technical guidance on recommended
procedures and on alternative procedures that may reduce costs.
Revisions to current State implementation plans (SIP's) are
required to use the alternative CE test methods described herein.
By calling these procedures "alternatives", the agency does not
intend to imply that they are more difficult to approve than the
"recommended" procedures where the stated criteria for approval
are satisfied. Guidance for implementing these SIP revisions is
provided in the cover memorandum.
1.3 Document organization
In Section 2.0, EPA's recommended protocols and test methods
are summarized. Section 3.0 presents two sets of criteria by
which alternative procedures can be approved, as well as the
recommended reporting requirements for using alternative
procedures. Section 4.0 presents a technical description for
aggregate sampling using the building as a TTE and for testing
multiple lines which share a common control device.
2.0 RECOMMENDED CAPTURE EFFICIENCY (CE) PROTOCOLS AND TEST
METHODS
The CE determination protocols and test methods recommended
by EPA are largely unchanged from those issued in the April 1990
guidance memo and codified in the Chicago FIP.1'2 The EPA
2
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continues to recommend the use of a PTE, TTE, or BE for
determining CE. When a TTE or BE is used, either a gas/gas
protocol or a liquid/gas protocol may be selected. The EPA test
methods for carrying out the recommended protocols have been
revised and will be proposed in the Federal Register for addition
to 40 CFR 51, Appendix M, as Method 204 through Method 204F.
Methods 204 through 204E were originally referred to as
Procedures T, L, G.I, G.2, F.I and F.2 respectively. Some
changes have been made to the test methods, so the latest version
i
of;the methods, which is included as an appendix, should be
consulted when planning CE testing. The draft revisions to date
are summarized below.
First, Appendix B, section 1.4, Sampling requirements.
originally contained a requirement that the sampling time for
each TTE and BE test run should be at least 8 hours, unless
otherwise approved. This provision has been revised to specify
that each TTE or BE run shall cover at least one complete
production cycle and must be at least 3 hours long. The sampling
time for each run need not exceed 8 hours, even if the production
cycle has not been completed. The maximum allowable time for a
test run is 24 hours. Alternative sampling times would be
subject to EPA approval.
Second, a new section on audit sample procedures has been
added to Procedure L, VQC Input.
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Third, the directions for analysis audits have been expanded
(newly added for Procedure L) to include information on audit
sample availability and reporting directions for audit results.
Next, a new method, Method 204F (called the distillation
approach), has been added for measuring liquid VOC input, as an
alternative to Procedure L.
Finally, Procedures T, Criteria for and Verification of a
Permanent or Temporary Total Enclosuref and F.2, Fugitive VOC
Emissions from Building Enclosures, have been revised to clarify
the acceptability criteria of a BE and to clarify which openings
in a building constitute an exhaust point or a natural draft
opening (NDO).
Table 2-1 lists the protocols, their associated EPA
recommended CE test methods, and the formulas for calculating CE.
Table 2-2 lists the EPA recommended CE test methods with the full
title of each. The PTE, TTE, and BE are discussed further in
Sections 2.1 through 2.3, respectively.
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TABLE 2-1.
Protocols
PTE
TTE —
gas/gas
TTE —
liquid/gas
BE —
gas/gas
BE —
liquid/gas
EPA recommended CE test methods
Enclosure
verification
M204
M204
M204
M204
M204
Liquid
input
(L)
NA
NA
M204A or
M204F
NA
M204A or
M204F
Captured
emissions
(G)
NA
M204B or
M204C
NA
M204B or
M204C
NA
Fugitive
emissions
(F) or
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TABLE 2-2.
Method
Method
Method
Method
Method
Method
Method
204
204A
204B
204C
204D
204E
204F
Criteria for and Verification of a Permanent
or Temporary Total Enclosure
Volatile Organic Compounds Content in Liquid
Input Stream
Volatile Organic Compounds Emissions in
Captured Stream
Volatile Organic Compounds Emissions in
Captured Stream (Dilution Technique)
Volatile Organic Compounds Emissions in
Fugitive Stream from Temporary Total
Enclosure
Volatile Organic Compounds Emissions in
Fugitive Stream from Building Enclosure
Volatile Organic Compounds Content in Liquid
Input Stream (Distillation Approach)
2.1 Permanent Total Enclosure
Method 204 lists the PTE requirements and the procedures for
verifying that an enclosure qualifies as a PTE. A PTE is an
enclosure that completely surrounds a source such that all
volatile organic compound (VOC) emissions are contained and
directed to a control device. If an enclosure meets the criteria
listed below then the enclosure is a PTE and the CE for the
source may be assumed to be 100 percent and need not be measured.
The PTE criteria are as follows:
1. Any NDO shall be at least 4 equivalent opening diameters
from each VOC-emitting point. An "equivalent diameter" is the
diameter of a circle that has the same area as the opening. The
equation for an equivalent diameter (ED) is:
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ED = I4 area)" Eq. 1
7T
For a circular NDO, this equation simply reduces to the diameter
of the opening.
2. The total area of all NDO's shall not exceed 5 percent
of the surface area of the enclosure's walls, floor, and ceiling.
3. The average face velocity (FV) of air through all NDO's
shall be at least 200 ft/min. The direction of air flow through
all NDO's shall be into the enclosure.
4. All access doors and windows whose areas are not
included as NDO's and are not included in the calculation of
FV shall be closed during routine operation of the process.4
1 5. All the exhaust gases from the enclosure are directed to
th^e control device.
If the PTE criteria are not met, then CE must be measured.
2.2 Temporary Total Enclosure
Method 204 lists the TTE requirements and the test
procedures for verifying that an enclosure qualifies as a TTE. A
TTE is an enclosure temporarily installed specifically for the CE
test.4 For an enclosure to qualify as a TTE, the criteria listed
below must be met. These five criteria ensure that all VOC's
are captured for measurement while minimizing disruption of
the capture normally achieved by the existing capture device(s)
in the absence of a TTE.4 The TTE criteria are as follows:
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1. Any NDO shall be at least 4 equivalent opening diameters
from each VOC-emitting point. An "equivalent diameter" is the
diameter of a circle that has the same area as the opening. The
equation for an equivalent diameter (ED) is:
ED = . Eg. 1
7T
For a circular NDO, this equation simply reduces to the diameter
of the opening.
2. The total area of all NDO's shall not exceed 5 percent
of the surface area of the enclosure's walls, floor, and ceiling.
3. The average face velocity (FV) of air through all NDO's
shall be at least 200 ft/min. The direction of air flow through
all NDO's shall be into the enclosure.
4. All access doors and windows whose areas are not
included as NDO's and are not included in the calculation of
FV shall be closed during routine operation of the process.4
5. Any exhaust point from the TTE shall be at least
4 equivalent duct or hood diameters from each NDO.
Two protocols may be used to measure the CE using a TTE, a
gas/gas protocol or a liquid/gas protocol. The associated test
methods and CE formula for each protocol are listed in Table 2-1.
2.3 Building Enclosure
Building enclosure protocols involve using the building that
houses the process as the enclosure. First, one must verify that
the BE meets the requirements for a TTE that are presented in
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Method 204. Then, using the procedures specified in Method 204E,
one must identify all the emission points from the building
enclosure (e.g., roof exhausts, windows, etc.) and determine
which emission points must be tested. Test procedures are given
for determining the flow rate and VOC concentration in the
exhaust from each of the various emission test points.
As with a TTE, two BE protocols may be used to measure the
CE, a gas/gas protocol or a liquid/gas protocol. The associated
test methods and CE formula for each protocol are listed in
Table 2-1.
3.0 REQUIREMENTS FOR ALTERNATIVE CE PROTOCOLS
To provide flexibility, EPA has developed two sets of
approval criteria which, when either of them is met, allow the
us£ of the data obtained with the alternative protocols and test
i
methods for determining CE. Alternative CE protocols and test
methods must meet either the requirements of the data quality
objective (DQO) approach or the lower confidence limit (LCL)
approach and the additional criteria presented below. The DQO,
LCL, and additional criteria are described in Sections 3.1, 3.2,
and 3.3, respectively. The recommended reporting requirements
for using alternative CE protocols and test methods are discussed
in Section 3.4.
NOTE: Although the Method 204 test series was developed for
i
TTE and BE testing, the same procedures can also be used in an
alternative CE test method. For example, a traditional
liquid/gas mass balance test could employ Method 204F to measure
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liquid VOC input and Method 204 B to measure captured VOC
emissions.
3.1 Data Quality Objective Approach
The purpose of the DQO is to allow sources to use
alternative CE test procedures while ensuring reasonable
precision consistent with pertinent requirements of the Clean Air
Act. The DQO requires that the width of the 2-sided 95 percent
confidence interval of the mean measured value be less than or
equal to 10 percent of the mean measured value (see Figure 1).
This ensures that 95 percent of the time, when the DQO is met,
the actual CE value will be ±5 percent of the mean measured value
(assuming that the test protocol is unbiased).
"a" < 0.05 xavg
UCL95
xav 95% confidence limit
"a" < 0.05 xavg
LCL95
Figure 1. Deviation around 95 percent (2-sided)
confidence interval.
Where:
a = distance from the average measured CE value to the
endpoints of the 95-percent (2-sided) confidence
interval that meets the DQO for the measured value.
LCL95 = Lower 95 percent confidence limit
UCL95 = Upper 95 percent confidence limit
xavg = Average CE value.
The DQO calculation is as follows:
10
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p =
.100
Eq. 2
avg
a =
0.975 s
Eq. 3
where;
a = distance from the average measured CE value to
the endpoints of the 95-percent (2-sided) confidence
interval for the measured value.
n = number of valid test runs.
P = DQO indicator statistic, distance from the
average measured CE value to the endpoints of
the 95-percent (2-sided) confidence interval,
expressed as a percent of the average
measured CE value.
s = sample standard deviation.
-0.975
t-value at the 95-percent confidence level (see
Table 3-1).
xavg = average measured CE value (calculated from all valid
test runs).
Xj = the CE value calculated from the ith test run.
The sample standard deviation and average CE value are
calculated as follows:
s =
n-1
0.5
Eq. 4
x
avg
E>.
n
Eq. 5
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Individual CE values greater than 105 percent are invalid
and cannot be used to calculate the average CE and DQO. The
source must have 3 valid test runs to use the DQO approach. The
DQO is achieved when P < 5 percent. In order to meet this
objective, facilities may have to conduct more than three test
runs. Examples of calculating P, given a finite number of test
runs, are shown below.
Number of
test runs, n
2
3
4
5
6
7
8
9
10
11
Q 975
12.706
4.303
3.182
2.776
2.571
2.447
2.365
2.306
2.262
2.228
1 Number of
test runs, n
3.078
1.886
1.638
1.533
1.476
1.440
1.415
1.397
1.383
1.372
12
13
14
15
16
17
18
19
20
21
^n 975
2.201
2.179
2.160
2.145
2.131
2.120
2.110
2.101
2.093
2.086
*-n 9n
1.363
1.356
1.350
1.345
1.341
1.337
1.333
1.330
1.328
1.325
TABLE 3-1. t-values.
Facility A conducted a CE test using a traditional liquid/gas
mass balance and submitted the following results:
Run CE
1 96,1
2 105.0
3 101.2
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therefore:
n = 3
to.975 = 4«30
xavg =100.8
s = 4.51
. (4.30) (4.51),llt20 £q> 6
P = ll'2 100 = 11.11 Eq. 7
110.8
Since the facility did not meet the DQO, they ran three more test
runs.
Run CE
4 93.2
5 96.2
6 87.6
i
The calculations for Runs 1-6 are as follows:
n =6
t0975 = 2.57
avg ~" "
S = 6.11
. (2.57) (6.11) .6-41 £q 8
P = lllilOO = 6.64
96.6
13
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The facility still did not meet the DQO. They ran three more
test runs with the following results:
Run CE
7 92.9
8 98.3
9 91.0
The calculations for Runs 1-9 are as follows:
n = 9
t0.975 = 2'31
Xav9 = 95.7
S = 5.33
a = J2_.31) (5.33) = A in
1/9
P = 4-1Q100 = 4.28 . Eq. 11
95.7
Based on these results, the average CE from the nine test runs
can be used to determine compliance.
3.2 Lower Confidence Limit Approach
The purpose of the LCL approach is to provide sources, who may be
performing much better than their applicable regulatory
requirement, a screening option by which they can demonstrate
compliance. The approach uses less precise methods and avoids
additional test runs which might otherwise be needed to meet the
DQO while still being assured of correctly demonstrating
compliance. It is designed to reduce "false positive" or so
14
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called "Type II errors" which may erroneously indicate compliance
where more variable test methods are employed. Because it
encourages CE performance greater than that required in exchange
for reduced compliance demonstration burden, the sources that
successfully use the LCL approach could produce emission
reductions beyond allowable emissions. Thus, it could provide
additional benefits to the environment as well.
The LCL approach compares the 80 percent (2-sided) LCL for
the mean measured CE value to the applicable CE regulatory
requirement. The LCL approach requires that either the LCL be
greater than or equal to the applicable CE regulatory requirement
or that the DQO is met. A more detailed description of the LCL
approach follows:
; A source conducts an initial series of at least three runs.
The source may choose to conduct additional test runs during the
initial test if it desires. All individual runs resulting in CE
values above 105 percent are invalid and cannot be used in
calculating the average CE and the LCL. If the data using only
the valid test runs meets the DQO, then the average CE value is
used to determine compliance. If the data does not meet the DQO
and the average CE, using all valid test runs, is above
100 percent then the test sequence is considered invalid. At
this point the facility has the option of (a) conducting more
test runs in hopes of meeting the DQO or of bringing the average
CE for all test runs below 100 percent or (b) discarding all
previous test data and retesting. [The purpose of this
I
15
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requirement is to protect against test methods which may be
inherently biased high. This is important because it is
theoretically impossible to have a CE greater than 100 percent
and the LCL approach only looks at the lower end variability of
the test results. This is different from the DQO which allows
average CE values up to 105 percent because the DQO sets both
upper and lower limits on test variability.] At any point during
testing when the results meet the DQO and the average CE is less
than 105 percent, the average CE can be used for demonstrating
compliance with the applicable regulatory requirement.
Similarly, if the average CE is below 100 percent then the LCL
can be used for demonstrating compliance with the applicable
regulatory requirement without regard to the DQO.
The LCL is calculated at a 80 percent (two-sided) confidence
level as follows:
r 1 3
- 12
where:
LC, = LCL at a 80 percent (two-sided) confidence level.
n = number of valid test runs.
s = sample standard deviation.
tQ 90 = t-value at the 80-percent (two-sided) confidence
level (see Table 3-1).
xavg = Average measured CE value (calculated from all valid
test runs).
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The resulting LC., is compared to the applicable CE
regulatory requirement. If LC1 exceeds (i.e. is higher than) the
applicable regulatory requirement, then a facility is in initial
compliance. However, if the LC, is below the CE requirement,
then the facility must conduct additional test runs. After this
point the test results will be evaluated not only looking at the
LCL but also the DQO of +5 percent of the mean at a 95 percent
confidence level. If the test results with the additional test
runs meet the DQO before the LCL exceeds the applicable CE
regulatory requirement, then the average CE value will be
compared to the applicable CE regulatory requirement for
determination of compliance.
If there is no specific CE requirement in the applicable
regulation, then the applicable CE regulatory requirement is
I
determined based on the applicable regulation and an acceptable
destruction efficiency test. If the applicable regulation
requires daily compliance and the latest CE compliance
demonstration was made using the LCL approach, then the
calculated LC1 will be the highest CE value which a facility is
allowed to claim until another CE demonstration test is
conducted. This last requirement is necessary to assure both
sufficiently reliable test results in all circumstances and the
potential environmental benefits referenced above.
i An example of calculating the LCL is shown below.
Facility B's applicable regulatory requirement is 85 percent CE.
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Facility B conducted a CE test using a traditional liquid/gas
mass balance and submitted the following results:
Run CE
1 94.2
2 97.6
3 90.5
therefore:
n = 3
t090 =1.886
Xavg = 94.1
S = 3.55
Lq-94.1-
Since the LC1 of 90.23 percent is above the applicable regulatory
reguirement of 85 percent then the facility is in compliance.
The facility must continue to accept the LC, of 90.23 percent as
its CE value until a new series of valid tests is conducted.
3.3 Additional Criteria
The Office of Air Quality Planning and Standards (OAQPS) has
developed an additional set of criteria that must be incorporated
into alternative CE protocols and associated test methods in
order for them to be approved. The following criteria apply:
1. A CE test shall consist of at least three sampling runs.
Each test run shall be at least 20 minutes long. The sampling
time for each run shall not exceed 24 hours.
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2. All test runs must be separate and independent. For
example, liquid VOC input and output must be determined
independently for each run. The final liquid VOC sample from one
run cannot be the initial sample for another run. In addition,
liquid input for an entire day cannot be apportioned among test
runs based on production.
3. Composite liquid samples will not be permitted to obtain
an "average composition" for a test run. For example, separate
initial and final coating samples must be taken and analyzed for
each run; initial and final samples cannot be combined prior to
analysis to derive an "average composition" for the test run.
4. All individual test runs that result in a CE of greater
than 105 percent are invalid and must be discarded. A test must
consist of at least 3 valid test runs.
5. If the source can demonstrate to the regulatory agency
that a run should not be considered due to an identified testing
or analysis error such as spillage of part of the sample during
shipping or an upset or improper operating conditions that is not
considered part of normal operation then the test result for that
individual run may be discarded. This limited exception allows
sources to discard as "outliers" certain individual runs without
replacing them with a valid run so long as the facility has at
least 3 valid test runs to use when calculating its DQO or LCL.
This exception is limited solely to test runs involving the types
of errors identified above.
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6. All valid test runs that are conducted must be included
in the average CE determination. The individual CE results and
average CE results cannot be truncated (i.e. 105 percent cannot
be reported as 100+ percent).
7. For the DQO approach the average CE for the test program
cannot be greater than 105 percent.
8. Alternative test methods for measuring VOC concentration
must include a three-point calibration of the gas analysis
instrument in the expected concentration range.
3.4 Reporting Requirements for Alternative CE Protocols
If a facility chooses to use alternative CE protocols and
test methods, the following information should be submitted with
each test report to the appropriate regulatory agency:
1. A copy of all alternative test methods, including any
changes to EPA reference methods, QA/QC procedures and
calibration procedures.
2. A table with information on each liquid sample,
including the sample identification, where and when the sample
was taken, and the VOC content of the sample;
3. The coating usage for each test run (for protocols in
which the liquid VOC input is to be determined);
4. The quantity of captured VOC measured for each test run;
5. The CE calculations and results for each test run;
6. The DQO or LCL calculations and results; and
20
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7. The QA/QC results, including information on calibrations
(e.g., how often the instruments were calibrated, the calibration
results, and information on calibration gases, if applicable).
3.5 Recordkeeping Requirements for Alternative CE Protocols.
A record should be kept at the facility of all raw data
recorded during the test in a suitable form for submittal to the
appropriate regulatory authority upon request.
4.0 MULTIPLE LINE TESTING
4.1 Aggregate Sampling
! A potential way to add further flexibility to determining CE
is to utilize aggregate sampling using a building enclosure.
This involves testing all regulated lines in the building
enclosure simultaneously. It must be noted that this technique
I
may not be feasible for all facilities. The applicable
\
regulations must be written to allow aggregate sampling and a
standard must be set for the building as a regulated entity. The
building must be able to meet the criteria in Method 204 for a
building enclosure and the building enclosure protocol described
in Section 2.3 must be followed.
4.2 Multiple Lines With Common Control Device
A second potential way to add further flexibility for
determining CE is to test multiple lines sharing a common control
device simultaneously. It must be noted that this technique may
not be feasible for all facilities. The applicable regulations
must be written to allow multiple line testing. The facility
must also meet additional guidelines as follows:
21
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1. The multiple lines roust share a common control device.
2. Multiple line testing may be performed using recommended
EPA protocols and test methods or alternative CE protocols and
test methods. The alternative protocols must meet the
requirements of Section 3.0.
3. The lines that are tested in combination are considered
to be in compliance only if the CE determined for the combination
of lines meets the most stringent CE required for any individual
line.
5.0 REFERENCES
1. Memorandum and attachments from Seitz, J.S., EPA/SSCD, to
Regional Office air division directors. April 16, 1990.
Guidelines for developing a State protocol for the
measurement of capture efficiency.
2. Office of the Federal Register. Control strategy: Ozone
[ control measures for Cook, DuPage, Kane, Lake, McHenry and
' Will Counties. 40 CFR 52.741. Washington, DC. U. S.
' Government Printing Office. 1992.
3. OAQPS. Model Volatile Organic Compound Rules for Reasonably
Available Control Technology. U. S. Environmental Protection
Agency. Research Triangle Park, NC. June 1992. pp. 340-
349.
4. The Measurement Solution: Using a Temporary Total Enclosure
for Capture Efficiency Testing. EPA-450/4-91-020. August
1991. Research Triangle Park, NC.
5. Mendenhall, W. Introduction to Probability and Statistics,
Third Edition. Belmont, California. Duxbury Press. 1971.
p. 419.
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APPENDIX
23
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DEC 14 1334
METHOD 204—CRITERIA FOR AMD VERIFICATION OF A PERMANENT OR
TEMPORARY TOTAL ENCLOSURE
1. INTRODUCTION
1.1 Applicability. This procedure is used to determine
whether a permanent or temporary enclosure meets the criteria for
a total enclosure. An existing building may be used as a
temporary or permanent enclosure as long as it meets the
appropriate criteria discribed in this method.
1.2 Principle. An enclosure is evaluated against a set of
criteria. If the criteria are met and if all the exhaust gases
from the enclosure are ducted to a control device, then the
volatile organic compounds (VOC) capture efficiency (CE) is
assumed to be 100 percent, and CE need not be measured. However,
if'part of the exhaust gas stream is not ducted to a control
i
deyice, CE must be determined.
1.3 Note. An evaluation of the proposed building materials
is recommended to minimize any potential hazards.
2. DEFINITIONS
2.1 Natural Draft Opening (NDO). Any permanent opening in
the enclosure that remains open during operation of the facility
and is not connected to a duct in which a fan is installed.
2.2 Permanent Total Enclosure (PE). A permanently installed
enclosure that completely surrounds a source of emissions such
that all VOC emissions are captured and contained for discharge
to a control device.
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2.3 Temporary Total Enclosure (TTE). A temporarily
installed enclosure that completely surrounds a source of
emissions such that all fugitive VOC emissions are captured and
contained for discharge through ducts that allow for the accurate
measurement of fugitive VOC emissions.
2.4 Building Enclosure (BE). An existing building that is
used as a TTE.
3. CRITERIA FOR TEMPORARY TOTAL ENCLOSURE
3.1 Any NDO shall be at least four equivalent opening
diameters from each VOC emitting point unless otherwise specified
by the Administrator.
3.2 Any exhaust point from the enclosure shall be at least
four equivalent duct or hood diameters from each NDO.
3.3 The total area of all NDO's shall not exceed 5 percent
of the surface area of the enclosure's four walls, floor, and
ceiling.
3.4 The average facial velocity (FV) of air through all
NDO's shall be at least 3,600 m/hr (200 fpm). The direction of
air flow through all NDO's shall be into the enclosure.
3.5 All access doors and windows whose areas are not
.included in Section 3.3 and are not included in the calculation
in Section 3.4 shall be closed during routine operation of the
process.
4. CRITERIA FOR A PERMANENT TOTAL ENCLOSURE
4.1 Same as Sections 3.1 and 3.3 through 3.5.
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4.2 All VOC emissions must be captured and contained for
discharge through a control device.
5. PROCEDURE
5.1 Determine the equivalent diameters of the NDO's and
determine the distances from each VOC emitting point to all
NDO's. Determine the equivalent diameter of each exhaust duct or
hood and its distance to all NDO's. Calculate the distances in
terms of equivalent diameters. The number of equivalent
diameters shall be at least four.
I
5.2 Measure the total area (AT) of the enclosure and the
total area (AN) of all NDO's in the enclosure. Calculate the NDO
to enclosure area ratio (NEAR) as follows:
AN
NEAR = _ Eq. 204-1
AT
The NEAR must be <0.05.
! 5.3 Measure the volumetric flow rate, corrected to standard
conditions, of each gas stream exiting the enclosure through an
exhaust duct or hood using EPA Method 2. In some cases (e.g.,
when the building is the enclosure), it may be necessary to
measure the volumetric flow rate, corrected to standard
conditions, of each gas stream entering the enclosure through a
i
forced makeup air duct using Method 2. Calculate FV using the
following equation:
-------
FV = °° " Ql Eq. 204-2
where :
Q0 = the sum of the volumetric flow from all gas streams
exiting the enclosure through an exhaust duct or
hood.
Q, = the sum of the volumetric flow from all gas streams
into the enclosure through a forced makeup air duct;
zero, if there is no forced makeup air into the
enclosure.
AN = total area of all NDO's in enclosure.
The FV shall be at least 3,600 m/hr (200 fpm) .
Alternatively, measure the pressure differential across the
enclosure. A pressure drop of 0.0075 mm Hg (0.004 in. H2O)
corresponds to an FV of 3,600 m/hr (200 fpm).
5.4 Verify that the direction of air flow through all NDO's
is inward. Streamers, smoke tubes, or tracer gases may be used.
Strips of plastic wrapping film have also been found to be
effective. Monitor the direction of air flow for at least
1 hour, with checks made no more than 10 minutes apart.
6. QUALITY ASSURANCE
6.1 The success of this method lies in designing the TTE to
simulate the conditions that exist without the TTE (i.e., the
effect of the TTE on the normal flow patterns around the affected
facility or the amount of fugitive VOC emissions should be
minimal) . The TTE must enclose the application stations, coating
reservoirs, and all areas from the application station to the
oven. The oven does not have to be enclosed if it is under
-------
negative pressure. The NDO's of the temporary enclosure and a
fugitive exhaust fan must be properly sized and placed.
6.2 Estimate the ventilation rate of the TTE that best
simulates the conditions that exist without the TTE (i.e., the
effect of the TTE on the normal flow patterns around the affected
facility or the amount of fugitive VOC emissions should be
minimal). Figure 204-1 may be used as an aid. Measure the
concentration (CG) and flow rate (QG) of the captured gas stream,
specify a safe concentration (CF) for the fugitive gas stream,
estimate the CE, and then use the plot in Figure 204-1 to
determine the volumetric flow rate of the fugitive gas stream
(QF). A fugitive VOC emission exhaust fan that has a variable
flow control is desirable.
6.3 Monitor the concentration of VOC into the capture device
i
without the TTE. To minimize the effect of temporal variation on
the captured emissions, the baseline measurement should be made
over as long a time period as practical. However, the process
conditions must be the same for the measurement in Section 6.5 as
they are for this baseline measurement. This may require short
measuring times for this quality control check before and after
the construction of the TTE.
6.4 After the TTE is constructed, monitor the VOC
concentration inside the TTE. This concentration shall not
continue to increase, and must not exceed the safe level
according to Occupational Safety and Health Administration
t
requirements for permissible exposure limits. An increase
-------
in VOC concentration indicates poor TTE design or poor capture
efficiency.
6.5 Monitor the concentration of VOC into the capture device
with the TTE. To limit the effect of the TTE on the process, the
VOC concentration with and without the TTE must be within 10
percent. If the measurements do not agree, adjust the
ventilation rate from the TTE until they agree within 10 percent.
-------
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o
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ill O
'—I 'O
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'•S~l\ iJ .
XI -C
C =J
ol >
Oj O
sis
*ji *j
t.
«J
o
8.0 r
i i
i i
/ .u
6.0
4 .\
2.0
2.0
1.0
0.90
0.SO r-
'
a:5oinr\
! \ ' '
0.;Or-7-
O.iO'1—
X
0.20
.=; .£ 0.1
0.09^
0.08
0.07
0.06
0.05
\
0.04
0.03
0.02
0.01
\
i i
80% CaptMre
\l I
98« Capture
0.5 1.0 1.5 2.0 2.5 3.0
Volumetric Flowrate of Fugitive Emissions Exhaust Stream ^F
^"™"™— ^•••^l^^™^*^*— M^^IMH -MMMHMBMB.MIIBBMBI—•^••«~B«IH*BI""MI—•-'^••^W 7 *""*"
Volumetric Flowrate of Gas Stream Delivered to the Control Device QQ
Figure 204-1. The crump!er chart.
X
i \
i r\L i i
i | | ^>^495S()
aptur
! \
6 'I 1
3.5
.7
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METHOD 204A—VOLATILE ORGANIC COMPOUNDS CONTENT IN LIQUID
INPUT STREAM
1. INTRODUCTION
1.1 Applicability. This procedure is applicable for
determining the input of VOC. It is intended to be used in
the development of liquid/gas protocols for determining VOC CE
for surface coating and printing operations.
•4
1.2 Principle. The amount of VOC introduced to the process
(L) is the sum of the products of the weight (W) of each VOC
containing liquid (ink, paint, solvent, etc.) used and its VOC
content (V). A sample of each VOC containing liquid is analyzed
with a flame ionization analyzer (FIA) to determine V.
1.3 Estimated Measurement Uncertainty. The measurement
uncertainties are estimated for each VOC containing liquid as
follows: W = ±2.0 percent and V = ±12.0 percent. Based on these
numbers, the probable uncertainty for L is estimated at about
±12.2 percent for each VOC containing liquid.
1.4 Sampling Requirements. A CE test shall consist of at
least three sampling runs. Each run shall cover at least one
complete production cycle, but shall be at least 3 hours long.
The sampling time for each run need not exceed 8 hours, even if
the production cycle has not been completed. Alternative
sampling times may be used with the approval of the
Administrator.
1.5 Notes. Because this procedure is often applied in
highly explosive areas, caution and care should be exercised in
choosing, installing, and using the appropriate equipment.
8
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Mention of trade names or company products does not constitute
endorsement. All gas concentrations (percent, ppm) are by
volume, unless otherwise noted.
2. APPARATUS AND REAGENTS
2.1 Liquid Weight.
2.1.1 Balances/Digital Scales. To weigh drums of VOC
containing liquids to within 0.2 Ib.
2.1.2 Volume Measurement Apparatus (Alternative). Volume
meters, flow meters, density measurement equipment, etc., as
needed to achieve the same accuracy as direct weight
measurements.
2.2 VOC Content (FIA Technique). The liquid sample analysis
system is shown in Figures 204A-1 and 204A-2. The following
equipment is required:
2.2.1 Sample Collection Can. An appropriately-sized metal
can to be used to collect VOC containing materials. The can must
be constructed in such a way that it can be grounded to the
coating container.
2.2.2 Needle Valves. To control gas flow.
2.2.3 Regulators. For carrier gas and calibration gas
cylinders.
2.2.4 Tubing. Teflon or stainless steel tubing with
diameters and lengths determined by connection requirements of
equipment. The tubing between the sample oven outlet and the FIA
shall be heated to maintain a temperature of 120 ± 5°C.
-------
2.2.5 Atmospheric Vent. A tee and 0- to 0.5-liter/min
rotameter placed in the sampling line between the carrier gas
cylinder and the VOC sample vessel to release the excess carrier
gas. A toggle valve placed between the tee and the rotameter
facilitates leak tests of the analysis system.
2.2.6 Thermometer. Capable of measuring the temperature of
the hot water bath to within 1°C.
2.2.7 Sample Oven. Heated enclosure, containing calibration
gas coil heaters, critical orifice, aspirator, and other liquid
sample analysis components, capable of maintaining a temperature
of 120 ± 5°C.
2.2.8 Gas Coil Heaters. Sufficient lengths of stainless
steel or Teflon tubing to allow zero and calibration gases to be
heated to the sample oven temperature before entering the
critical orifice or aspirator.
2.2.9 Water Bath. Capable of heating and maintaining a
sample vessel temperature of 100 ± 5°C.
2.2.10 Analytical Balance. To measure ±0.001 g.
2.2.11 Disposable syringes. 2-cc or 5-cc.
2.2.12 Sample Vessel. Glass, 40-ml septum vial. A separate
vessel is needed for each sample.
2.2.13 Rubber Stopper. Two-hole stopper to accommodate
3.2-mm (l/8-in.) Teflon tubing, appropriately sized to fit the
opening of the sample vessel. The rubber stopper should be
wrapped in Teflon tape to provide a tighter seal and to prevent
any reaction of the sample with the rubber stopper.
10
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Alternatively, any leak-free closure fabricated of nonreactive
materials and accommodating the necessary tubing fittings may be
used.
2.2.14 Critical Orifices. Calibrated critical orifices
capable of providing constant flow rates from 50 to 250 ml/min at
known pressure drops. Sapphire orifice assemblies (available
from O'Keefe Controls Company) and glass capillary tubing have
been found to be adequate for this application.
2.2.15 Vacuum Gauge. Zero to 760-mm (0- to 30-in.) Hg
I
i
U-Tube manometer or vacuum gauge.
2.2.16 Pressure Gauge. Bourdon gauge capable of measuring
the maximum air pressure at the aspirator inlet (e.g., 100 psig).
, 2.2.17 Aspirator. A device capable of generating sufficient
I
vacjuum at the sample vessel to create critical flow through the
calibrated orifice when sufficient air pressure is present at the
aspirator inlet. The aspirator must also provide sufficient
sample pressure to operate the FIA. The sample is also mixed
with the dilution gas within the aspirator.
2.2.18 Soap Bubble Meter. Of an appropriate size to
calibrate the critical orifices in the system.
2.2.19 Organic Concentration Analyzer. An FIA with a span
value of 1.5 times the expected concentration as propane;
however, other span values may be used if it can be demonstrated
that they would provide more accurate measurements. The FIA
instrument should be the same instrument used in the gaseous
analyses adjusted with the same fuel, combustion air, and sample
11
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back-pressure (flow rate) settings. The system shall be capable
of meeting or exceeding the following specifications:
2.2.19.1 Zero Drift. Less than ±3.0 percent of the span
value.
2.2.19.2 Calibration Drift, Less than ±3.0 percent of the
span value.
2.2.19.3 Calibration Error. Less than ±5.0 percent of the
calibration gas value.
2.2.20 Integrator/Data Acquisition System. An analog or
digital device or computerized data acquisition system used to
integrate the FIA response or compute the average response and
record measurement data. The minimum data sampling frequency for
computing average or integrated values is one measurement value
every 5 seconds. The device shall be capable of recording
average values at least once per minute.
2.2.21 Chart Recorder (Optional). A chart recorder or
similar device is recommended to provide a continuous analog
display of the measurement results during the liquid sample
analysis.
2.2.22 Calibration and Other Gases. Gases used for
calibration, fuel, and combustion air (if required) are contained
in compressed gas cylinders. All calibration gases shall be
traceable to National Institute of Standards and Technology
standards and shall be certified by the manufacturer to
±1 percent of the tag value. Additionally, the manufacturer of
.f^.
1 the cylinder should provide a recommended shelf life for each
calibration gas cylinder over which the concentration does not
12
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change more than ±2 percent from the certified value. For
calibration gas values not generally available, alternative
methods for preparing calibration gas mixtures, such as dilution
systems, may be used with the approval of the Administrator.
2.2.22.1 Fuel. The FIA manufacturer's fuel should be used.
A 40 percent H2/60 percent He or 40 percent H2/60 percent N2 gas
mixture is recommended to avoid an oxygen synergism effect that
reportedly occurs when oxygen concentration varies significantly
from a mean value.
2.2.22.2 Carrier Gas. High purity air with less than 1 ppm
of organic material (as propane) or less than 0.1 percent of the
span value, whichever is greater.
, 2.2.22.3 FIA Linearity Calibration Gases. Low-, mid-, and
high-range gas mixture standards with nominal propane
concentrations of 20-30, 45-55, and 70-80 percent of the span
value in air, respectively. Other calibration values and other
sp^n values may be used if it can be shown to the Administrator's
satisfaction that more accurate measurements would be achieved.
2.2.22.4 System Calibration Gas. Gas mixture standard
containing propane in air, approximating the undiluted VOC
concentration expected for the liquid samples.
3. DETERMINATION OF LIQUID INPUT WEIGHT
3.1 Weight Difference. Determine the amount of material
introduced to the process as the weight difference of the feed
material before and after each sampling run. In determining the
total VOC containing liquid usage, account for:
(a) The initial (beginning) VOC containing liquid mixture.
13
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(b) Any solvent added during the test run.
(c) Any coating added during the test run.
(d) Any residual VOC containing liquid mixture remaining at
the end of the sample run.
3.1.1 Identify all points where VOC containing liquids are
introduced to the process. To obtain an accurate measurement of
VOC containing liquids, start with an empty fountain (if
applicable). After completing the run, drain the liquid in the
fountain back into the liquid drum (if possible) and weigh the
drum again. Weigh the VOC containing liquids to ±0.5 percent of
the total weight (full) or ±0.1 percent of the total weight of
VOC containing liquid used during the sample run, whichever is
less. If the residual liquid cannot be returned to the drum,
drain the fountain into a preweighed empty drum to determine the
final weight of the liquid.
3.1.2 If it is not possible to measure a single
representative mixture, then weigh the various components
separately (e.g., if solvent is added during the sampling run,
weigh the solvent before it is added to the mixture). If a fresh
drum of VOC containing liquid is needed during the run, then
weigh both the empty drum and fresh drum.
3.2 Volume Measurement (Alternative). If direct weight
measurements are not feasible, the tester may use volume meters
and flow rate meters (and density measurements) to determine the
weight of liquids used if it can be demonstrated that the
14
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technique produces results equivalent to the direct weight
measurements. If a single representative mixture cannot be
measured, measure the components separately.
4. DETERMINATION OP VOC CONTENT IN INPUT LIQUIDS
4.1 Collection of Liquid Samples.
4.1.1 Collect a 100-ml or larger sample of the VOC
containing liquid mixture at each application location at the
beginning and end of each test run. A separate sample should be
taken of each VOC containing liquid added to the application
mixture during the test run. If a fresh drum is needed during
the sampling run, then obtain a sample from the fresh drum.
4.1.2 When collecting the sample, ground the sample
container to the coating drum. Fill the sample container as
close to the rim as possible to minimize the amount of headspace.
4.1.3 After the sample is collected, seal the container so
I
the sample cannot leak out or evaporate.
4.1.4 Label the container to clearly identify the contents.
4.2 Liquid Sample VOC Content.
, 4.2.1 Assemble the liquid VOC content analysis system as
shown in Figure 204A-1.
4.2.2 Permanently identify all of the critical orifices that
may be used. Calibrate each critical orifice under the expected
operating conditions (i.e., sample vacuum and temperature)
against a volume meter as described in Section 5.3.
4.2.3 Label and tare the sample vessels (including the
stoppers and caps) and the syringes.
15
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4.2.4 Install an empty sample vessel and perform a leak test
of the system. Close the carrier gas valve and atmospheric vent
and evacuate the sample vessel to 250 mm (10 in.) Hg absolute or
less using the aspirator. Close the toggle valve at the inlet to
the aspirator and observe the vacuum for at least 1 minute. If
there is any change in the sample pressure, release the vacuum,
adjust or repair the apparatus as necessary, and repeat the leak
test.
4.2.5 Perform the analyzer calibration and linearity checks
according to the procedure in Section 5.1. Record the responses
to each of the calibration gases and the back-pressure setting of
the FIA.
4.2.6 Establish the appropriate dilution ratio by adjusting
the aspirator air supply or substituting critical orifices.
Operate the aspirator at a vacuum of at least 25 mm (1 in.) Hg
greater than the vacuum necessary to achieve critical flow.
Select the dilution ratio so that the maximum response of the FIA
to the sample does not exceed the high-range calibration gas.
4.2.7 Perform system calibration checks at two levels by
introducing compressed gases at the inlet to the sample vessel
while the aspirator and dilution devices are operating. Perform
these checks using the carrier gas (zero concentration) and the
system calibration gas. If the response to the carrier gas
exceeds ±0.5 percent of span, clean or repair the apparatus and
repeat the check. Adjust the dilution ratio as necessary to
achieve the correct response to the upscale check, but do not
adjust the analyzer calibration. Record the identification of
16
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the orifice, aspirator air supply pressure, FIA back-pressure,
and the responses of the FIA to the carrier and system
calibration gases.
4.2.8 After completing the above checks, inject the system
calibration gas for approximately 10 minutes. Time the exact
duration of the gas injection using a stopwatch. Determine the
area under the FIA response curve and calculate the system
response factor based on the sample gas flow rate, gas
concentration, and the duration of the injection as compared to
the!integrated response using Equations 204A-2 and 204A-3.
'4.2.9 Verify that the sample oven and sample line
temperatures are 120 ± 5°C and that the water bath temperature is
100 ± 5°C.
4.2.10 Fill a tared syringe with approximately 1 g of the
VOC containing liquid and weigh it. Transfer the liquid to a
tared sample vessel. Plug the sample vessel to minimize sample
loss. Weigh the sample vessel containing the liquid to determine
the amount of sample actually received. Also, as a quality
control check, weigh the empty syringe to determine the amount of
material delivered. The two coating sample weights should agree
within 0.02 g. If not, repeat the procedure until an acceptable
sample is obtained.
4.2.11 Connect the vessel to the analysis system. Adjust
the aspirator supply pressure to the correct value. Open the
valve on the carrier gas supply to the sample vessel and adjust
it to provide a slight excess flow to the atmospheric vent. As
soon as the initial response of the FIA begins to decrease,
17
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immerse the sample vessel in the water bath. (Applying heat to
the sample vessel too soon may cause the FIA response to exceed
the calibrated range of the instrument and, thus, invalidate the
analysis.)
4.2.12 Continuously measure and record the response of the
FIA until all of the volatile material has been evaporated from
the sample and the instrument response has returned to the
baseline (i.e., response less than 0.5 percent of the span
value). Observe the aspirator supply pressure, FIA
back-pressure, atmospheric vent, and other system operating
parameters during the run; repeat the analysis procedure if any
of these parameters deviate from the values established during
the system calibration checks in Section 4.2.7. After each
sample, perform the drift check described in Section 5.2. If the
drift check results are acceptable, calculate the VOC content of
the sample using the equations in Section 7. Integrate the area
under the FIA response curve, or determine the average
concentration response and the duration of sample analysis.
5. CALIBRATION AND QUALITY ASSURANCE
5.1 FIA Calibration and Linearity Check. Make necessary
adjustments to the air and fuel supplies for the FIA and ignite
the burner. Allow the FIA to warm up for the period recommended
by the manufacturer. Inject a calibration gas into the
measurement system and adjust the back-pressure regulator to the
value required to achieve the flow rates specified by the
manufacturer. Inject the zero- and the high-range calibration
18
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gases and adjust the analyzer calibration to provide the proper
responses. Inject the low- and mid-range gases and record the
responses of the measurement system. The calibration and
linearity of the system are acceptable if the responses for all
four gases are within 5 percent of the respective gas values. If
the performance of the system is not acceptable, repair or adjust
the system and repeat the linearity check. Conduct a calibration
and linearity check after assembling the analysis system and
after a major change is made to the system.
5.2 Systems Drift Checks. After each sample, repeat the
system calibration checks in Section 4.2.7 before any adjustments
to the FIA or measurement system are made. If the zero or
calibration drift exceeds ±3 percent of the span value, discard
the result and repeat the analysis.
! 5.3 Critical orifice Calibration.
5.3.1 Each critical orifice must be calibrated at the
specific operating conditions under which it will be used.
Therefore, assemble all components of the liquid sample analysis
system as shown in Figure 204A-3. A stopwatch is also required.
5.3.2 Turn on the sample oven, sample line, and water bath
heaters, and allow the system to reach the proper operating
temperature. Adjust the aspirator to a vacuum of 380 mm (15 in.)
Hg vacuum. Measure the time required for one soap bubble to move
a known distance and record barometric pressure.
5.3.3 Repeat the calibration procedure at a vacuum of 406 mm
(16 in.) Hg and at 25-mm (1-in.) Hg intervals until three
19
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consecutive determinations provide the same flow rate. Calculate
the critical flow rate for the orifice in ml/min at standard
conditions. Record the vacuum necessary to achieve critical
flow.
5.4 Audits.
5.4.1 Audit Procedure. Concurrently, analyze the audit
sample and a set of compliance samples in the same manner to
evaluate the technique of the analyst and the standards
preparation. The same analyst, analytical reagents, and
analytical system shall be used both for compliance samples and
the EPA audit sample. If this condition is met, auditing of
subsequent compliance analyses for the same enforcement agency
within 30 days is not required. An audit sample set may not be
used to validate different sets of compliance samples under the
jurisdiction of different enforcement agencies, unless prior
arrangements are made with both enforcement agencies.
5.4.2 Audit Samples and Audit Sample Availability. Audit
samples will be supplied only to enforcement agencies for
compliance tests. The availability of audit samples may be
obtained by writing:
Source Test Audit Coordinator (STAC) (MD-77B)
Quality Assurance Division
Atmospheric Research and Exposure Assessment Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
or by calling the STAC at (919) 541-7834. The request for the
audit sample must be made at least 30 days prior to the scheduled
compliance sample analysis.
20
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5.4.3 Audit Results. Calculate the audit sample
concentration according to the calculation procedure described in
the audit instructions included with the audit sample. Fill in
the audit sample concentration and the analyst's name on the
audit response form included with the audit instructions. Send
one copy to the EPA Regional Office or the appropriate
enforcement agency, and a second copy to the STAC. The EPA
Regional Office or the appropriate enforcement agency will report
the results of the audit to the laboratory being audited.
i
Include this response with the results of the compliance samples
i
in relevant reports to the EPA Regional Office or the appropriate
enforcement agency.
i
6. NOMENCLATURE
, AL = area under the response curve of the liquid sample, area
count.
1 AS = area under the response curve of the calibration gas,
area count.
I
Cs = actual concentration of system calibration gas, ppm
propane.
K = 1.830 x 10'9 g/(ml-ppm).
L = total VOC content of liquid input, kg.
I
ML = mass of liquid sample delivered to the sample vessel, g.
q = flow rate through critical orifice, ml/min.
RF = liquid analysis system response factor, g/area count.
0S = total gas injection time for system calibration gas
during integrator calibration, min.
VFj. = final VOC fraction of VOC containing liquid j.
V, = initial VOC fraction of VOC containing liquid j.
21
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V.. = VOC fraction of VOC containing liquid j added during the
*J
run.
V = VOC fraction of liquid sample.
WFj = weight of VOC containing liquid j remaining at end of
the run, kg.
W^ = weight of VOC containing liquid j at beginning of the
run, kg.
WAJ = weight of VOC containing liquid j added during the run,
kg.
7. CALCULATIONS
7.1 Total VOC Content of the Input VOC Containing Liquid.
ii WU - X>j Wn + £ VA; WAJ Ec*'
j =1 j =1
7.2 Liquid Sample Analysis System Response Factor for
Systems Using Integrators, Grams/Area Count.
RF = °s q s K Eq. 204A-2
As
7.3 VOC Content of the Liquid Sample.
V =Al RF Eq. 204A-3
22
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ro
CO
ATMOSPHERIC
VENT
0-0.5 LPM
ROTAMETER
UPC,
ZERO AIR.
OR EQUIVALENT
SAMPLE OVEN
THERMOMETER
LINEARITY
CALIBRATION GASES
HEATED SAMPLE OVEN
SAMPLE BYPASS
ROTAMETER
0-10 LPM
GAS
HEATING COILS
BACK
PRESSURE
REGULATOR
CRITICAL
ORIFICE
WATER BATH
THERMOMETER
0-30- Hg
U-TUBE MANOMETER
OR VACUUM GAGE
VOC
SAMPLE
VESSEL
Figure 204A-1. Liquid analysis sample system.
-------
TEFLON SAMPLE LINE
TO
FIA
C cc GLASS VESSEL
ULTRA PURE
CARRIER GAS
CRITICAL ORIFICE
RUBBER STOPPER
WITH TEFLON TAPE
Figure 204A-2. VOC sampling vessel.
24
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en
BUBBLE
METER
UPC.
ZERO AIR,
OR EQUIVALENT
SAMPLE OVEN
THERMOMETER
PRESSURE
GAGE
LINEARITY
CALIBRATION GASES
HEATED SAMPLE OVEN
SAMPLE BYPASS
ROTAMETER
0-10 LPM
GAS
HEATING COILS
FID EXHAUST
INTEGRATOR/
BACK
PRESSURE
REGULATOR
CRITICAL
ORIFICE
WATER BATH
THERMOMETER
HEATED
SAMPLE
LINE
0 - 30- Hg
U-TUBE MANOMETER
OR VACUUM GAGE
VOC
SAMPLE
VESSEL
Figure 204A-3. Critical orifice calibration apparatus.
-------
METHOD 204B—VOLATILE ORGANIC COMPOUNDS EMISSIONS IN
CAPTURED STREAM
1. INTRODUCTION
1.1 Applicability. This procedure is applicable for
determining the VOC content of captured gas streams. It is
intended to be used in the development of liquid/gas or gas/gas
protocols for determining VOC CE for surface coating and printing
operations. The procedure may not be acceptable in certain
site-specific situations [e.g., when: (1) direct-fired heaters or
other circumstances affect the quantity of VOC at the control
device inlet; and (2) particulate organic aerosols are formed in
the process and are present in the captured emissions].
1.2 Principle. The amount of VOC captured (G) is calculated
as the sum of the products of the VOC content (C .), the flow
rate (QGj) , and the sample time (6C) from each captured emissions
point.
1.3 Estimated Measurement Uncertainty. The measurement
uncertainties are estimated for each captured or fugitive
emissions point as follows: QG- = ±5.5 percent and
CCj- = ±5.0 percent. Based on these numbers, the probable
uncertainty for G is estimated at about ±7.4 percent.
1.4 Sampling Requirements. A CE test shall consist of at
least three sampling runs. Each run shall cover at least
one complete production cycle, but shall be at least 3 hours
long. The sampling time for each run need not exceed 8 hours,
even if the production cycle has not been completed.
26
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Alternative sampling times may be used with the approval of the
Administrator.
1.5 Notes. Because this procedure is often applied in
highly explosive areas, caution and care should be exercised in
choosing, installing, and using the appropriate equipment.
Mention of trade names or company products does not constitute
endorsement. All gas concentrations (percent, ppm) are by
volume, unless otherwise noted.
2. APPARATUS AND REAGENTS
2.1 Gas VOC Concentration. A schematic of the measurement
system is shown in Figure 204B-1. The main components are as
follows:
2.1.1 Sample Probe. Stainless steel or equivalent. The
probe shall be heated to prevent VOC condensation.
! 2.1.2 Calibration Valve Assembly. Three-way valve assembly
I
at the outlet of the sample probe to direct the zero and
calibration gases to the analyzer. Other methods, such as
quick-connect lines, to route calibration gases to the outlet of
the sample probe are acceptable.
2.1.3 Sample Line. Stainless steel or Teflon tubing to
transport the sample gas to the analyzer. The sample line must
be heated to prevent condensation.
2.1.4 Sample Pump. A leak-free pump, to pull the sample gas
through the system at a flow rate sufficient to minimize the
response time of the measurement system. The components of the
pump that contact the gas stream shall be constructed of
27
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stainless steel or Teflon. The sample pump must be heated to
prevent condensation.
2.1.5 Sample Flow Rate Control. A sample flow rate control
valve and rotameter, or equivalent, to maintain a constant
sampling rate within 10 percent. The flow rate control valve and
rotameter must be heated to prevent condensation. A control
valve may also be located on the sample pump bypass loop to
assist in controlling the sample pressure and flow rate.
2.1.6 organic Concentration Analyzer. An FIA with a span
value of 1.5 times the expected concentration as propane;
however, other span values may be used if it can be demonstrated
to the Administrator's satisfaction that they would provide more
accurate measurements. The system shall be capable of meeting or
exceeding the following specifications:
2.1.6.1 Zero Drift. Less than ±3.0 percent of the span
value.
2.1.6.2 Calibration Drift. Less than ±3.0 percent of the
span value.
2.1.6.3 Calibration Error. Less than ±5.0 percent of the
calibration gas value.
2.1.6.4 Response Time. Less than 30 seconds.
2.1.7 Integrator/Data Acquisition System. An analog or
digital device, or computerized data acquisition system used to
integrate the FIA response or compute the average response and
record measurement data. The minimum data sampling frequency for
computing average or integrated values is one measurement value
28
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every 5 seconds. The device shall be capable of recording
average values at least once per minute.
2.1.8 Calibration and Other Gases. Gases used for
calibration, fuel, and combustion air (if required) are contained
in compressed gas cylinders. All calibration gases shall be
traceable to National Institute of Standards and Technology
standards and shall be certified by the manufacturer to
±1 percent of the tag value. Additionally, the manufacturer of
the cylinder should provide a recommended shelf life for each
calibration gas cylinder over which the concentration does not
change more than ±2 percent from the certified value. For
calibration gas values not generally available, alternative
methods for preparing calibration gas mixtures, such as dilution
systems, may be used with the approval of the Administrator.
2.1.8.1 Fuel. The FIA manufacturer's recommended fuel
should be used. A 40 percent H2/60 percent He or
40 percent H2/60 percent N2 gas mixture is recommended to avoid
an oxygen synergism effect that reportedly occurs when oxygen
concentration varies significantly from a mean value.
2.1.8.2 Carrier Gas. High purity air with less than 1 ppm
of organic material (as propane or carbon equivalent) or less
than 0.1 percent of the span value, whichever is greater.
2.1.8.3 FIA Linearity calibration Gases. Low-, mid-, and
high-range gas mixture standards with nominal propane
concentrations of 20-30, 45-55, and 70-80 percent of the span
value in air, respectively. Other calibration values and other
29
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span values may be used if it can be shown to the Administrator's
satisfaction that more accurate measurements would be achieved.
2.1.9 Particulate Filter. An in-stack or an out-of-stack
glass fiber filter is recommended if exhaust gas particulate
loading is significant. An out-of-stack filter must be heated to
prevent any condensation unless it can be demonstrated that no
condensation occurs.
2.2 Captured Emissions Volumetric Flow Rate.
2.2.1 Method 2 or 2A Apparatus. For determining volumetric
flow rate.
2.2.2 Method 3 Apparatus and Reagents. For determining
molecular weight of the gas stream. An estimate of the molecular
weight of the gas stream may be used if approved by the
Administrator.
2.2.3 Method 4 Apparatus and Reagents. For determining
moisture content, if necessary.
3. DETERMINATION OF VOLUMETRIC FLOW RATE OF CAPTURED
EMISSIONS
3.1 Locate all points where emissions are captured from the
affected facility. Using Method I, determine the sampling
points. Be sure to check each site for cyclonic or swirling
flow.
3.2 Measure the velocity at each sampling site at least once
every hour during each sampling run using Method 2 or 2A.
4. DETERMINATION OF VOC CONTENT OF CAPTURED EMISSIONS
30
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4.1 Analysis Duration. Measure the VOC responses at each
captured emissions point during the entire test run or, if
applicable, while the process is operating. If there are
multiple captured emission locations, design a sampling system to
allow a single FIA to be used to determine the VOC responses at
all sampling locations.
4.2 Gas VOC Concentration.
4.2.1 Assemble the sample train as shown in Figure 204B-1.
Calibrate the FIA according to the procedure in Section 5.1.
4.2.2 Conduct a system check according to the procedure in
Section 5.3.
i 4.2.3 Install the sample probe so that the probe is
centrally located in the stack, pipe, or duct, and is sealed
tightly at the stack port connection.
4.2.4 Inject zero gas at the calibration valve assembly.
Allow the measurement system response to reach zero. Measure the
system response time as the time required for the system to reach
the effluent concentration after the calibration valve has been
returned to the effluent sampling position.
4.2.5 Conduct a system check before, and a system drift
check after, each sampling run according to the procedures in
Sections 5.2 and 5.3. If the drift check following a run
indicates unacceptable performance (see Section 5.3), the run is
not valid. The tester may elect to perform system drift checks
during the run not to exceed one drift check per hour.
31
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4.2.6 Verify that the sample lines, filter, and pump
temperatures are 120 ± 5°C.
4.2.7 Begin sampling at the start of the test period and
continue to sample during the entire run. Record the starting
and ending times and any required process information as
appropriate. If multiple captured emission locations are sampled
using a single FIA, sample at each location for the same amount
of time (e.g., 2 minutes) and continue to switch from one
location to another for the entire test run. Be sure that total
sampling time at each location is the same at the end of the test
run. Collect at least four separate measurements from each
sample point during each hour of testing. Disregard the
measurements at each sampling location until two times the
response time of the measurement system has elapsed. Continue
sampling for at least 1 minute and record the concentration
measurements.
4.3 Background Concentration. NOTE: Not applicable when
the building is used as the TTE.
4.3.1 Locate all NDO's of the TTE. A sampling point shall
be at the center of each NDO, unless otherwise specified by the
Administrator. If there are more than six NDO's, choose six
sampling points evenly spaced among the NDO's.
4.3.2 Assemble the sample train as shown in Figure 204B-2.
Calibrate the FIA and conduct a system check according to the
procedures in Sections 5.1 and 5.3. NOTE: This sample train
32
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shall be separate from the sample train used to measure the
captured emissions.
4.3.3 Position the probe at the sampling location.
4.3.4 Determine the response time, conduct the system check,
and sample according to the procedures described in
Sections 4.2.4 through 4.2.7.
4.4 Alternative Procedure. The direct interface sampling
and analysis procedure described in Section 7.2 of Method 18 may
be used to determine the gas VOC concentration. The system must
be idesigned to collect and analyze at least one sample every
10 minutes.
5. CALIBRATION AND QUALITY ASSURANCE
5.1 FIA Calibration and Linearity Check. Make necessary
I
adjustments to the air and fuel supplies for the FIA and ignite
the burner. Allow the FIA to warm up for the period recommended
by;the manufacturer. Inject a calibration gas into the
measurement system and adjust the back-pressure regulator to the
*•
value required to achieve the flow rates specified by the
manufacturer. Inject the zero- and the high-range calibration
gases and adjust the analyzer calibration to provide the proper
responses. Inject the low- and mid-range gases and record the
responses of the measurement system. The calibration and
linearity of the system are acceptable if the responses for all
four gases are within 5 percent of the respective gas values, if
the performance of the system is not acceptable, repair or adjust
the system and repeat the linearity check. Conduct a calibration
33
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and linearity check after assembling the analysis system and
after a major change is made to the system.
5.2 Systems Drift Checks. Select the calibration gas that
most closely approximates the concentration of the captured
emissions for conducting the drift checks. Introduce the zero
and calibration gases at the calibration valve assembly and
verify that the appropriate gas flow rate and pressure are
present at the FIA. Record the measurement system responses to
the zero and calibration gases. The performance of the system is
acceptable if the difference between the drift check measurement
and the value obtained in Section 5.1 is less than 3 percent of
the span value. Conduct the system drift checks at the end of
each run.
5.3 System Check. Inject the high-range calibration gas at
the inlet of the sampling probe and record the response. The
performance of the system is acceptable if the measurement system
response is within 5 percent of the value obtained in Section 5.1
%
for the high-range calibration gas. Conduct a system check
before and after each test run.
5.4 Audits.
5.4.1 Analysis Audit Procedure. Immediately before each
test, analyze an audit cylinder as described in Section 5.2. The
analysis audit must agree with the audit cylinder concentration
within 10 percent.
5.4.2 Audit Samples and Audit Sample Availability. Audit
samples will be supplied only to enforcement agencies for
34
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compliance tests. The availability of audit samples may be
obtained by writing:
Source Test Audit Coordinator (STAC) (MD-77B)
Quality Assurance Division
Atmospheric Research and Exposure Assessment Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
or by calling the STAC at (919) 541-7834. The request for the
audit sample must be made at least 30 days prior to the scheduled
compliance sample analysis.
5.4.3 Audit Results. Calculate the audit sample
concentration according to the calculation procedure described in
the audit instructions included with the audit sample. Fill in
the audit sample concentration and the analyst's name on the
i
audit response form included with the audit instructions. Send
one copy to the EPA Regional Office or the appropriate
enforcement agency, and a second copy to the STAC. The EPA
Regional Office or the appropriate enforcement agency will report
the results of the audit to the laboratory being audited.
Include this response with the results of the compliance samples
in relevant reports to the EPA Regional Office or the appropriate
enforcement agency.
6. NOMENCLATURE
AJ - area of NDO i, ft2.
AH = total area of all NDO's in the enclosure, ft2.
CBi = corrected average VOC concentration of background
' emissions at point i, ppm propane.
CB = average background concentration, ppm propane.
35
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CGj = corrected average VOC concentration of captured
emissions at point j, ppm propane.
CDH = average measured concentration for the drift check
calibration gas, ppm propane.
CDO = average system drift check concentration for zero
concentration gas, ppm propane.
CH = actual concentration of the drift check calibration gas,
ppm propane.
Cj = uncorrected average background VOC concentration
measured at point i, ppm propane.
Cj = uncorrected average VOC concentration measured at point
j , ppm propane .
G = total VOC content of captured emissions, kg.
K, = 1.830 x 10*6 kg/(m3-ppm).
n = number of measurement points.
QGj = average effluent volumetric flow rate corrected to
standard conditions at captured emissions point j,
m3/min.
6C = total duration of captured emissions.
7 . CALCULATIONS
7.1 Total VOC Captured Emissions.
G = E
-------
7.3 Background VOC Concentration at Point i.
=•1 " (C, - CDO)__ii_ Eq. 204B-3
7.4 Average Background Concentration.
C -
CB ~
Eq. 204B-4
NOTE: If the concentration at each point is within 20 percent of
the average concentration of all points, then use the arithmetic
average.
37
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DUCT
SINGLE POINT
PROBE AT
MIDDLE OF DUCT
GO
oo
L
HEATED
PARTICULATE
FILTER
to
N
CALIBRATION
VALVE
ASSEMBLY
IU
O
1
I
IU
o
i
6
EXCESS
SAMPLE
SAMPIE BYPASS
FID EXHAUST
MOFAMETER =
SAMPLE MANIFOLD
O
1
O
I
FUME
IONIZATION
ANALYZER
INTEGRATOR/
DATA
ACQUISITION
SYSTEM
CHART
RECORDER
(OPTIONAL)
LEGEND
NEEDLE VALVE
SAMPLE LINES
SIGNAL LINES
Figure 204B-1. Gas VOC concentration measurement system.
-------
TEI LONIIEAD
SAMPLE PUMP
-A-
o
cc
:ODM
• i
•AcoS
UJ
O
2
cr
O
UJ
cc
o
2
BACK
PRESSURE
AIOR
SAMPIE
BYPASS
FIA
EXHAUST
EXHAUST
0-
ANALYZER
GAS IN.IECTIOM
VAIVE
PI AME
IOMIZAIION
ANALYZER
CO
CO
CONTROL
VALVE
| MEASUREMENT POINV 1
MEASUHEMENn'OINT 2
MEASUREMENT POINT 3
MEASUREMEN I POIN
MEASUREMENT COIN I 5
SAMPLING
MANIEOLD
DATA
ACQUISITION
SYSTEM
Cl IART
RECORDER
-CO
CO
UJ
NEEDIE
VALVES
ROTAME1ERS
THREE
WAY
VALVES
Fignre 20AB-2. Background measurement system.
-------
METHOD 204C—VOLATILE ORGANIC COMPOUNDS EMISSIONS IN CAPTURED
STREAM (DILUTION TECHNIQUE)
1. INTRODUCTION
1.1 Applicability. This procedure is applicable for
determining the VOC content of captured gas streams. It is
intended to be used in the development of a gas/gas protocol in
which fugitive emissions are measured for determining VOC
CE for surface coating and printing operations. A dilution
system is used to reduce the VOC concentration of the
captured emissions to about the same concentration as the
fugitive emissions. The procedure may not be acceptable in
certain site-specific situations [e.g., when: (1) direct-fired
heaters or other circumstances affect the quantity of
VOC at the control device inlet; and (2) particulate organic
aerosols are formed in the process and are present in the
captured emissions].
1.2 Principle. The amount of VOC captured (G) is calculated
as the sum of the products of the VOC content (CG-) , the flow
rate (QGj) , and the sampling time (0C) from each captured
emissions point.
1.3 Estimated Measurement Uncertainty. The measurement
uncertainties are estimated for each captured or fugitive
emissions point as follows: Qc. = ±5.5 percent and
CQj = ±5 percent. Based on these numbers, the probable
uncertainty for G is estimated at about ±7.4 percent.
40
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1.4 Sampling Requirements. A CE test shall consist of at
least three sampling runs. Each run shall cover at least one
complete production cycle, but shall be at least 3 hours long.
The sampling time for each run need not exceed 8 hours, even if
the production cycle has not been completed. Alternative
sampling times may be used with the approval of the
Administrator.
1.5 Notes. Because this procedure is often applied in
highly explosive areas, caution and care should be exercised in
choosing, installing, and using the appropriate equipment.
Mention of trade names or company products does not constitute
endorsement. All gas concentrations (percent, ppm) are by
volume, unless otherwise noted.
! 2. APPARATUS AND REAGENTS
2.1 Gas VOC Concentration. A schematic of the measurement
I
system is shown in Figure 204C-1. The main components are as
follows:
2.1.1 Dilution System. A Kipp in-stack dilution probe and
controller or similar device may be used. The dilution rate may
be changed by substituting different critical orifices or
adjustments of the aspirator supply pressure. The dilution
system shall be heated to prevent VOC condensation. Note: An
out-of-stack dilution device may be used.
2.1.2 Calibration Valve Assembly. Three-way valve assembly
at the outlet of the sample probe to direct the zero and
calibration gases to the analyzer. Other methods, such as
41
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quick-connect lines, to route calibration gases to the outlet of
the sample probe are acceptable.
2.1.3 Sample Line. Stainless steel or Teflon tubing to
transport the sample gas to the analyzer. The sample line must
be heated to prevent condensation.
2.1.4 Sample Pump. A leak-free pump, to pull the sample gas
through the system at a flow rate sufficient to minimize the
response time of the measurement system. The components of the
pump that contact the gas stream shall be constructed of
stainless steel or Teflon. The sample pump must be heated to
prevent condensation.
2.1.5 Sample Flow Rate Control. A sample flow rate control
valve and rotameter, or equivalent, to maintain a constant
sampling rate within 10 percent. The flow control valve and
rotameter must be heated to prevent condensation. A control
valve may also be located on the sample pump bypass loop to
assist in controlling the sample pressure and flow rate.
2.1.6 Sample Gas Manifold. Capable of diverting a portion
of the sample gas stream to the FIA, and the remainder to the
bypass discharge vent. The manifold components shall be
constructed of stainless steel or Teflon. If captured or
fugitive emissions are to be measured at multiple locations, the
measurement system shall be designed to use separate sampling
probes, lines, and pumps for each measurement location and a
common sample gas manifold and FIA. The sample gas manifold and
42
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connecting lines to the FIA must be heated to prevent
condensation. NOTE: Depending on the number of sampling points
and their location, it may not be possible to use only one FIA.
However to reduce the effect of calibration error, the number of
FIA's used during a test should be keep as small as possible.
2.1.7 Organic Concentration Analyzer. An FIA with a span
value of 1.5 times the expected concentration as propane;
however, other span values may be used if it can be demonstrated
to the Administrator's satisfaction that they would provide more
accurate measurements. The system shall be capable of meeting or
exceeding the following specifications:
2.1.7.1 Zero Drift. Less than ±3.0 percent of the span
value.
I
, 2.1.7.2 Calibration Drift. Less than ±3.0 percent of the
span value.
2.1.7.3 calibration Error. Less than ±5.0 percent of the
calibration gas value.
2.1.7.4 Response Time. Less than 30 seconds.
2.1.8 Integrator/Data Acquisition System. An analog or
digital device or computerized data acquisition system used to
integrate the FIA response or compute the average response and
record measurement data. The minimum data sampling frequency for
computing average or integrated values is one measurement value
every 5 seconds. The device shall be capable of recording
average values at least once per minute.
43
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2.1.9 Calibration and Other Gases. Gases used for
calibration, fuel, and combustion air (if required) are contained
in compressed gas cylinders. All calibration gases shall be
traceable to National Institute of Standards and Technology
standards and shall be certified by the manufacturer to
±1 percent of the tag value. Additionally, the manufacturer of
the cylinder should provide a recommended shelf life for each
calibration gas cylinder over which the concentration does not
change more than ±2 percent from the certified value. For
calibration gas values not generally available, alternative
methods for preparing calibration gas mixtures, such as dilution
systems, may be used with the approval of the Administrator.
2.1.9.1 Fuel. The FIA manufacturer's recommended fuel
should be used. A 40 percent H2/60 percent He or
40 percent H2/60 percent N2 gas mixture is recommended to avoid
an oxygen synergism effect that reportedly occurs when oxygen
concentration varies significantly from a mean value.
2.1.9.2 Carrier Gas and Dilution Air Supply. High purity
air with less than 1 ppm of organic material (as propane or
carbon equivalent), or less than 0.1 percent of the span value,
whichever is greater.
2.1.9.3 FIA Linearity Calibration Gases. Low-, mid-, and
high-range gas mixture standards with nominal propane
concentrations of 20-30, 45-55, and 70-80 percent of the span
value in air, respectively. Other calibration values and other
44
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span values may be used if it can be shown to the Administrator's
satisfaction that more accurate measurements would be achieved.
2.1.9.4 Dilution Check Gas. Gas mixture standard containing
propane in air, approximately half the span value after dilution.
2.1.10 Particulate Filter. An in-stack or an out-of-stack
glass fiber filter is recommended if exhaust gas particulate
loading is significant. An out-of-stack filter must be heated to
prevent any condensation unless it can be demonstrated that no
condensation occurs.
2.2 Captured Emissions Volumetric Flow Rate.
2.2.1 Method 2 or 2A Apparatus. For determining volumetric
flow rate.
2.2.2 Method 3 Apparatus and Reagents. For determining
molecular weight of the gas stream. An estimate of the molecular
i
weight of the gas stream may be used if approved by the
Administrator.
2.2.3 Method 4 Apparatus and Reagents. For determining
moisture content, if necessary.
3. DETERMINATION OF VOLUMETRIC FLOW RATE OF CAPTURED
EMISSIONS
3.1 Locate all points where emissions are captured from the
affected facility. Using Method 1, determine the sampling
points. Be sure to check each site for cyclonic or swirling
flow.
3.2 Measure the velocity at each sampling site at least once
every hour during each sampling run using Method 2 or 2A.
45
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4. DETERMINATION OF VOC CONTENT OF CAPTURED EMISSIONS
4.1 Analysis Duration. Measure the VOC responses at each
captured emissions point during the entire test run or, if
applicable, while the process is operating. If there are
multiple captured emissions locations, design a sampling system
to allow a single FIA to be used to determine the VOC responses
at all sampling locations.
4.2 Gas VOC Concentration.
4.2.1 Assemble the sample train as shown in Figure 204C-1.
Calibrate the FIA according to the procedure in Section 5.1.
4.2.2 Set the dilution ratio and determine the dilution
factor according to the procedure in Section 5.3.
4.2.3 Conduct a system check according to the procedure in
Section 5.4.
4.2.4 Install the sample probe so that the probe is
centrally located in the stack, pipe, or duct, and is sealed
tightly at the stack port connection.
4.2.5 Inject zero gas at the calibration valve assembly.
Measure the system response time as the time reguired for the
system to reach the effluent concentration after the calibration
valve has been returned to the effluent sampling position.
4.2.6 Conduct a system check before, and a system drift
check after, each sampling run according to the procedures in
Sections 5.2 and 5.4. If the drift check following a run
indicates unacceptable performance (see Section 5.4), the run is
46
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not valid. The tester may elect to perform system drift checks
during the run not to exceed one drift check per hour.
4.2.7 Verify that the sample lines, filter, and pump
temperatures are 120 ± 5°C.
4.2.8 Begin sampling at the start of the test period and
continue to sample during the entire run. Record the starting
and ending times and any required process information as
appropriate. If multiple captured emission locations are sampled
using a single FIA, sample at each location for the same amount
of time (e.g., 2 min.) and continue to switch from one location
to another for the entire test run. Be sure that total sampling
time at each location is the same at the end c1 the test run.
Collect at least four separate measurements from each sample
i
point during each hour of testing. Disregard the measurements at
each sampling location until two times the response time of the
measurement system has elapsed. Continue sampling for at least
1 minute and record the concentration measurements.
4.3 Background Concentration. NOTE: Not applicable when
I
the building is used as the TTE.
4.3.1 Locate all NDO's of the TTE. A sampling point shall
be at the center of each NDO, unless otherwise approved by the
i
Administrator. If there are more than six NDO's, choose six
sampling points evenly spaced among the NDO's.
4.3.2 Assemble the sample train as shown in Figure 204C-2.
Calibrate the FIA and conduct a system check according to the
procedures in Sections 5.1 and 5.4.
47
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4.3.3 Position the probe at the sampling location.
4.3.4 Determine the response time, conduct the system check,
and sample according to the procedures described in
Sections 4.2.4 through 4.2.8.
4.4 Alternative Procedure. The direct interface sampling
and analysis procedure described in Section 7.2 of Method 18 may
be used to determine the gas VOC concentration. The system must
be designed to collect and analyze at least one sample every
10 minutes.
5. CALIBRATION AND QUALITY ASSURANCE
5.1 FIA Calibration and Linearity Check. Make necessary
adjustments to the air and fuel supplies for the FIA and ignite
the burner. Allow the FIA to warm up for the period recommended
by the manufacturer. Inject a calibration gas into the
measurement systerr. after the dilution system and adjust the
back-pressure regulator to the value required to achieve the flow
rates specified by the manufacturer. Inject the zero- and the
high-range calibration gases and adjust the analyzer calibration
to provide the proper responses. Inject the low- and mid-range
gases and record the responses of the measurement system. The
calibration and linearity of the system are acceptable if the
responses for all four gases are within 5 percent of the
respective gas values. If the performance of the system is not
acceptable, repair or adjust the system and repeat the linearity
check. Conduct a calibration and linearity check after
48
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assembling the analysis system and after a major change is made
to the system.
5.2 Systems Drift Checks. Select the calibration gas that
most closely approximates the concentration of the diluted
captured emissions for conducting the drift checks. Introduce
the zero and calibration gases at the calibration valve assembly,
and verify that the appropriate gas flow rate and pressure are
present at the FIA. Record the measurement system responses to
the zero and calibration gases. The performance of the system is
acceptable if the difference between the drift check measurement
and the value obtained in Section 5.1 is less than 3 percent of
the span value. Conduct the system drift check at the end of
each run.
5.3 Determination of Dilution Factor. Inject the dilution
check gas into the measurement system before the dilution system
and record the response. Calculate the dilution factor using
Equation 204C-3.
5.4 System Check. Inject the high-range calibration gas at
the inlet to the sampling probe while the dilution air is turned
off. Record the response. The performance of the system is
acceptable if the measurement system response is within 5 percent
of the value obtained in Section 5.1 for the high-range
calibration gas. Conduct a system check before and after each
test run.
49
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5.5 Audits.
5.5.1 Analysis Audit Procedure. Immediately before each
test, analyze an audit cylinder as described in Section 5.2. The
analysis audit must agree with the audit cylinder concentration
within 10 percent.
5.5.2 Audit Samples and Audit Sample Availability. Audit
samples will be supplied only to enforcement agencies for
compliance tests. The availability of audit samples may be
obtained by writing:
Source Test Audit Coordinator (STAC) (MD-77B)
Quality Assurance Division
Atmospheric Research and Exposure Assessment Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
or by calling the STAC at (919) 541-7834. The request for the
audit sample must be made at least 30 days prior to the scheduled
compliance sample analysis.
5.5.3 Audit Results. Calculate the audit sample
concentration according to the calculation procedure described in
the audit instructions included with the audit sample. Fill in
the audit sample concentration and the analyst's name on the
audit response form included with the audit instructions. Send
one copy to the EPA Regional Office or the appropriate
enforcement agency, and a second copy to the STAC. The EPA
Regional Office or the appropriate enforcement agency will report
the results of the audit to the laboratory being audited.
Include this response with the results of the compliance samples
50
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in relevant reports to the EPA Regional Office or the appropriate
enforcement agency.
6. NOMENCLATURE
AJ = area of NDO i, ft2.
AN = total area of all NDO's in the enclosure, ft2.
CA = actual concentration of the dilution check gas, ppm
propane.
CBi = corrected average VOC concentration of background
emissions at point i, ppm propane.
CB = average background concentration, ppm propane.
CDH = average measured concentration for the drift check
calibration gas, ppm propane.
CDO = average system drift check concentration for zero
concentration gas, ppm propane.
CH = actual concentration of the drift check calibration gas,
ppm propane.
Cj = uncorrected average background VOC concentration
measured at point i, ppm propane.
Cj = uncorrected average VOC concentration measured at point
j, ppm propane.
CM = measured concentration of the dilution check gas, ppm
propane.
DF = dilution factor.
G = total VOC content of captured emissions, kg.
K, = 1.830 x 10'6 kg/(m3-ppm).
i
n = number of measurement points.
QGj = average effluent volumetric flow rate corrected to
standard conditions at captured emissions point j,
m3/min.
Oc = total duration of CE sampling run, min.
51
-------
7. CALCULATIONS
7.1 Total VOC Captured Emissions.
G = E QGJ *c *1
Eq. 204C-1
7.2 VOC Concentration of the Captured Emissions at Point j.
CH
_J! Eq. 204C-2
CGj = DF (Cj - CDO)
7.3 Dilution Factor.
DF = _
CM
Eq. 204C-3
7.4 Background VOC Concentration at Point i
j CDO)
Eq. 204C-4
7.5 Average Background Concentration.
c =
*-
Eq. 204C-5
NOTE: If the concentration at each point is within 20 percent of
the average concentration of all points, then use the arithmetic
average.
52
-------
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Tignrc 201C-1. Captured emissions measurement system.
-------
SAMPI E
OYI'ASS
EXHAUST
en
HA
EXHAUST
MOIAMtILM
TEFLON HEAD
SAMPLE PUMP
II AMI:
IONIZAIION
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-------
METHOD 204D—VOLATILE ORGANIC COMPOUNDS EMISSIONS IN FUGITIVE
STREAM FROM TEMPORARY TOTAL ENCLOSURE
1. INTRODUCTION
1.1 Applicability. This procedure is applicable for
determining the fugitive VOC emissions from a TTE. It is
intended to be used as a segment in the development of liquid/gas
or gas/gas protocols for determining VOC CE for surface coating
and printing operations.
i 1.2 Principle. The amount of fugitive VOC emissions (F)
from the TTE is calculated as the sum of the products of the VOC
content (Cf.) , the flow rate (QF:) from each fugitive emissions
point, and the sampling time (6f) .
1.3 Estimated Measurement Uncertainty. The measurement
i
uncertainties are estimated for each fugitive emission point as
t
follows: QFj = ±5.5 percent and Cf. = ±5.0 percent.
Based on these numbers, the probable uncertainty for F is
estimated at about ±7.4 percent.
1.4 Sampling Requirements. A CE test shall consist of at
least three sampling runs. Each run shall cover at least one
complete production cycle, but shall be at least 3 hours long.
The sampling time for each run need not exceed 8 hours, even if
the production cycle has not been completed. Alternative
sampling times may be used with the approval of the
Administrator.
1.5 Notes. Because this procedure is often applied in
highly explosive areas, caution and care should be exercised in
55
-------
choosing, installing, and using the appropriate equipment.
Mention of trade names or company products does not constitute
endorsement. All gas concentrations (percent, ppm) are by
volume, unless otherwise noted.
2. APPARATUS AND REAGENTS
2.1 Gas VOC Concentration. A schematic of the measurement
system is shown in Figure 204D-1. The main components are as
follows:
2.1.1 Sample Probe. Stainless steel or equivalent. The
probe shall be heated to prevent VOC condensation.
2.1.2 Calibration Valve Assembly. Three-way valve assembly
at the outlet of the sample probe to direct the zero and
calibration gases to the analyzer. Other methods, such as
quick-connect lines, to route calibration gases to the outlet of
the sample probe are acceptable.
2.1.3 Sample Line. Stainless steel or Teflon tubing to
transport the sample gas to the analyzer. The sample line must
be heated to prevent condensation.
2.1.4 Sample Pump. A leak-free pump, to pull the sample gas
through the system at a flow rate sufficient to minimize the
response time of the measurement system. The components of the
pump that contact the gas stream shall be constructed of
stainless steel or Teflon. The sample pump must be heated to
prevent condensation.
2.1.5 Sample Flow Rate Control. A sample flow rate control
valve and rotameter, or equivalent, to maintain a constant
56
-------
sampling rate within 10 percent. The flow control valve and
rotameter must be heated to prevent condensation. A control
valve may also be located on the sample pump bypass loop to
assist in controlling the sample pressure and flow rate.
2.1.6 Sample Gas Manifold. Capable of diverting a portion
of the sample gas stream to the FIA, and the remainder to the
bypass discharge vent. The manifold components shall be
constructed of stainless steel or Teflon. If emissions are to be
measured at multiple locations, the measurement system shall be
designed to use separate sampling probes, lines, and pumps for
each measurement location and a common sample gas manifold and
FIA. The sample gas manifold and connecting lines to the FIA
must be heated to prevent condensation.
2.1.7 Organic Concentration Analyzer. An FIA with a span
value of 1.5 times the expected concentration as propane;
however, other span values may be used if it can be demonstrated
to the Administrator's satisfaction that they would provide more
accurate measurements. The system shall be capable of meeting or
exceeding the following specifications:
2.1.7.1 Zero Drift. Less than ±3.0 percent of the span
value.
2.1.7.2 Calibration Drift. Less than ±3.0 percent of the
span value.
i
2.1.7.3 Calibration Error. Less than ±5.0 percent of the
calibration gas value.
2.1.7.4 Response Time. Less than 30 seconds.
57
-------
2.1.8 Integrator/Data Acquisition System. An analog or
digital device or computerized data acquisition system used to
integrate the FIA response or compute the average response and
record measurement data. The minimum data sampling frequency for
computing average or integrated values is one measurement value
every 5 seconds. The device shall be capable of recording
average values at least once per minute.
2.1.9 Calibration and Other Gases. Gases used for
calibration, fuel, and combustion air (if required) are contained
in compressed gas cylinders. All calibration gases shall be
traceable to National Institute of Standards and Technology
standards and shall be certified by the manufacturer to
±1 percent of the tag value. Additionally, the manufacturer of
the cylinder should provide a recommended shelf life for each
calibration gas cylinder over which the concentration does not
change more than ±2 percent from the certified value. For
calibration gas values not generally available, alternative
methods for preparing calibration gas mixtures, such as dilution
systems, may be used with the approval of the Administrator.
2.1.9.1 Fuel. The FIA manufacturer's recommended fuel
should be used. A 40 percent H2/60 percent He or
40 percent H2/60 percent N2 gas mixture is recommended to avoid
an oxygen synergism effect that reportedly occurs when oxygen
concentration varies significantly from a mean value.
58
-------
2.1.9.2 Carrier Gas. High purity air with less than l ppm
of organic material (as propane or carbon equivalent) or less
than 0.1 percent of the span value, whichever is greater.
2.1.9.3 FIA Linearity Calibration Gases. Low-, mid-, and
high-range gas mixture standards with nominal propane
concentrations of 20-30, 45-55, and 70-80 percent of the span
value in air, respectively. Other calibration values and other
span values may be used if it can be shown to the Administrator's
satisfaction that more accurate measurements would be achieved.
2.1.10 Particulate Filter. An in-stack or an out-of-stack
glass fiber filter is recommended if exhaust gas particulate
loading is significant. An out-of-stack filter must be heated to
prevent any condensation unless it can be demonstrated that no
condensation occurs.
' 2.2 Fugitive Emissions Volumetric Flow Rate.
I 2.2.1 Method 2 or 2A Apparatus. For determining volumetric
flow rate.
1 2.2.2 Method 3 Apparatus and Reagents. For determining
molecular weight of the gas stream. An estimate of the molecular
weight of the gas stream may be used if approved by the
Administrator.
2.2.3 Method 4 Apparatus and Reagents. For determining
moisture content, if necessary.
2.3 Temporary Total Enclosure. The criteria for designing
an acceptable TTE are specified in Method 204.
59
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3. DETERMINATION OF VOLUMETRIC FLOW RATE OF FUGITIVE
EMISSIONS
3.1 Locate all points where emissions are exhausted from the
TTE. Using Method 1, determine the sampling points. Be sure to
check each site for cyclonic or swirling flow.
3.2 Measure the velocity at each sampling site at least once
every hour during each sampling run using Method 2 or 2A.
4. DETERMINATION OF VOC CONTENT OF FUGITIVE EMISSIONS
4.1 Analysis Duration. Measure the VOC responses at each
fugitive emission point during the entire test run or, if
applicable, while the process is operating. If there are
multiple emission locations, design a sampling system to allow a
single FIA to be used to determine the VOC responses at all
sampling locations.
4.2 Gas VOC Concentration.
4.2.1 Assemble the sample train as shown in Figure 204D-1.
Calibrate the FIA and conduct a system check according to the
procedures in Sections 5.1 and 5.3, respectively.
4.2.2 Install the sample probe so that the probe is
centrally located in the stack, pipe, or duct, and is sealed
tightly at the stack port connection.
4.2.3 Inject zero gas at the calibration valve assembly.
Allow the measurement system response to reach zero. Measure the
system response time as the time reguired for the system to reach
the effluent concentration after the calibration valve has been
returned to the effluent sampling position.
60
-------
4.2.4 Conduct a system check before, and a system drift
check after, each sampling run according to the procedures in
Sections 5.2 and 5.3. If the drift check following a run
indicates unacceptable performance (see Section 5.3), the run is
not valid. The tester may elect to perform system drift checks
during the run not to exceed one drift check per hour.
4.2.5 Verify that the sample lines, filter, and pump
temperatures are 120 ± 5°C.
4.2.6 Begin sampling at the start of the test period and
i
continue to sample during the entire run. Record the starting
and ending times and any required process information, as
appropriate. If multiple emission locations are sampled using a
single FIA, sample at each location for the same amount of time
(e..g., 2 min.) and continue to switch from one location to
I
another for the entire test run. Be sure that total sampling
time at each location is the same at the end of the test run.
Collect at least four separate measurements from each sample
point during each hour of testing. Disregard the response
measurements at each sampling location until 2 times the response
time of the measurement system has elapsed. Continue sampling
for at least 1 minute and record the concentration measurements.
i
4.3 Background Concentration.
4.3.1 Locate all NDO's of the TTE. A sampling point shall
be at the center of each NDO, unless otherwise approved by the
Administrator. If there are more than six NDO's, choose six
sampling points evenly spaced among the NDO's.
61
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4.3.2 Assemble the sample train as shown in Figure 204D-2.
Calibrate the FIA and conduct a system check according to the
procedures in Sections 5.1 and 5.3.
4.3.3 Position the probe at the sampling location.
4.3.4 Determine the response time, conduct the system check,
and sample according to the procedures described in
Sections 4.2.3 through 4.2.6.
4.4 Alternative Procedure. The direct interface sampling
and analysis procedure described in Section 7.2 of Method 18 may
be used to determine the gas VOC concentration. The system must
be designed to collect and analyze at least one sample every
10 minutes.
5. CALIBRATION AND QUALITY ASSURANCE
5.1 FIA Calibration and Linearity Check. Make necessary
adjustments to the air and fuel supplies for the FIA and ignite
the burner. Allow the FIA to warm up for the period recommended
by the manufacturer. Inject a calibration gas into the
measurement system and adjust the back-pressure regulator to the
value required to achieve the flow rates specified by the
manufacturer. Inject the zero- and the high-range calibration
gases and adjust the analyzer calibration to provide the proper
responses. „ Inject the low- and mid-range gases and record the
responses of the measurement system. The calibration and
linearity of the system are acceptable if the responses for all
four gases are within 5 percent of the respective gas values. If
the performance of the system is not acceptable, repair or adjust
62
-------
the system and repeat the linearity check. Conduct a calibration
and linearity check after assembling the analysis system and
after a major change is made to the system.
5.2 Systems Drift Checks. Select the calibration gas
concentration that most closely approximates that of the fugitive
gas emissions to conduct the drift checks. Introduce the zero
and calibration gases at the calibration valve assembly and
verify that the appropriate gas flow rate and pressure are
present at the FIA. Record the measurement system responses to
the zero and calibration gases. The performance of the system is
acceptable if the difference between the drift check measurement
and the value obtained in Section 5.1 is less than 3 percent of
the span value. Conduct a system drift check at the end of each
run.
i 5.3 System Check. Inject the high-range calibration gas at
the inlet of the sampling probe and record the response. The
performance of the system is acceptable if the measurement system
response is within 5 percent of the value obtained in Section 5.1
for the high-range calibration gas. Conduct a system check
before each test run.
5.4 Audits.
I
5.4.1 Analysis Audit Procedure. Immediately before each
test, analyze an audit cylinder as described in Section 5.2. The
analysis audit must agree with the audit cylinder concentration
within 10 percent.
63
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5.4.2 Audit Samples and Audit Sample Availability. Audit
samples will be supplied only to enforcement agencies for
compliance tests. The availability of audit samples may be
obtained by writing:
Source Test Audit Coordinator (STAC) (MD-77B)
Quality Assurance Division
Atmospheric Research and Exposure Assessment Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
or by calling the STAC at (919) 541-7834. The request for
the audit sample must be made at least 30 days prior to the
scheduled compliance sample analysis.
5.4.3 Audit Results. Calculate the audit sample
concentration according to the calculation procedure described in
the audit instructions included with the audit sample. Fill in
the audit sample concentration and the analyst's name on the
audit response form included with the audit instructions. Send
one copy to the EPA Regional Office or the appropriate
enforcement agency, and a second copy to the STAC. The EPA
Regional Office or the appropriate enforcement agency will report
the results of the audit to the laboratory being audited.
Include this response with the results of the compliance samples
in relevant reports to the EPA Regional Office or the appropriate
enforcement agency.
6. NOMENCLATURE
A,- = area of NDO i, ft2.
AN = total area of all NDO's in the enclosure, ft2.
64
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CBi = corrected average VOC concentration of background
emissions at point i, ppm propane.
CB = average background concentration, ppm propane.
CDH = average measured concentration for the drift check
calibration gas, ppm propane.
CDO = average system drift check concentration for zero
concentration gas, ppm propane.
Cr = corrected average VOC concentration of fugitive
emissions at point j, ppm propane.
CH = actual concentration of the drift check calibration gas,
ppm propane.
Cj = uncorrected average background VOC concentration at
point i, ppm propane.
Cj = uncorrected average VOC concentration measured at
point j, ppm propane.
F = total VOC content of fugitive emissions, kg.
K, = 1.830 x 10'6 kg/(m3-ppm).
n = number of measurement points.
Qf. - average effluent volumetric flow rate corrected to
standard conditions at fugitive emissions point j,
m3/min.
0F = total duration of fugitive emissions sampling run, min.
7. CALCULATIONS
7.1 Total VOC Fugitive Emissions.
n
F = £
-------
7.2 VOC Concentration of the Fugitive Emissions at Point j.
j - CDO) H Eq. 204D-2
'-DH
7.3 Background VOC Concentration at Point i
CBI =
-------
SAMPLE
BYPASS
EXHAUST
FIA
EXHAUST
TEFLON HEAD
SAMPLE PUMP
FLAMf:
IONIZAI ION
ANALYZER
ANALYZER
GAS INJECTION
VALVE
I FUGITIVE EMISSION POINT 1
FUGITIVE EMISSION POINT 2
FUGITIVE EMISSION POINT 3
FUGITIVE EMISSION POINT 4
FUGITIVE EMISSION POINT 5
NEEDLE
VALVES
SAMPLING
MANIFOLD
ROTAMETERS
THREE
WAY
VALVES
DATA
ACQUISITION
SYSTEM
CHART
RECORDER
Figure 2040-1. Fugitive emissions measurement system.
-------
EXIIAUST
O)
oo
TEFLON HEAD
SAMPLE PUMP
o
-------
METHOD 204E—VOLATILE ORGANIC COMPOUNDS EMISSIONS IN FUGITIVE
STREAM FROM BUILDING ENCLOSURE
1. INTRODUCTION
1.1 Applicability. This procedure is applicable for
determining the fugitive VOC emissions from a building enclosure
(BE). It is intended to be used in the development of liquid/gas
or gas/gas protocols for determining VOC CE for surface coating
and printing operations.
1.2 Principle. The total amount of fugitive VOC emissions
(FB) from the BE is calculated as the sum of the
products of the VOC content (CFj) of each fugitive emissions
point, the flow rate (QFj) at each fugitive emissions point, and
time (0F).
1.3 Measurement Uncertainty. The measurement uncertainties
are estimated for each fugitive emissions point as follows:
QFj = ±10.0 percent and CFj = ±5.0 percent. Based on these
numbers, the probable uncertainty for FB is estimated at about
±11.2 percent.
i
1.4 Sampling Requirements. A CE test shall consist of at
least three sampling runs. Each run shall cover at least one
complete production cycle, but shall be at least 3 hours long.
The sampling time for each run need not exceed 8 hours, even if
the production cycle has not been completed. Alternative
sampling times may be used with the approval of the
Administrator.
i
' 1.5 Notes. Because this procedure is often applied in
highly explosive areas, caution and care should be exercised in
69
-------
choosing, installing, and using the appropriate equipment.
Mention of trade names or company products does not constitute
endorsement. All gas concentrations (percent, ppm) are by
volume, unless otherwise noted.
2. Apparatus and Reagents
2.1 Gas VOC Concentration. A schematic of the measurement
system is shown in Figure 204E-1. The main components are as
follows:
2.1.1 Sample Probe. Stainless steel or equivalent. The
probe shall be heated to prevent VOC condensation.
2.1.2 Calibration Valve Assembly. Three-way valve assembly
at the outlet of the sample probe to direct the zero and
calibration gases to the analyzer. Other methods, such as
quick-connect lines, to route calibration gases to the outlet of
the sample probe are acceptable.
2.1.3 Sample Line. Stainless steel or Teflon tubing to
transport the sample gas to the analyzer. The sample line must
be heated to prevent condensation.
2.1.4 Sample Pump. A leak-free pump, to pull the sample gas
through the system at a flow rate sufficient to minimize the
response time of the measurement system. The components of the
pump that contact the gas stream shall be constructed of
stainless steel or Teflon. The sample pump must be heated to
prevent condensation.
2.1.5 Sample Flow Rate Control. A sample flow rate control
valve and rotameter, or equivalent, to maintain a constant
70
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sampling rate within 10 percent. The flow rate control valve and
rotameter must be heated to prevent condensation. A control
valve may also be located on the sample pump bypass loop to
assist in controlling the sample pressure and flow rate.
2.1.6 Sample Gas Manifold. Capable of diverting a portion
of the sample gas stream to the FIA, and the remainder to the
bypass discharge vent. The manifold components shall be
constructed of stainless steel or Teflon. If emissions are to be
measured at multiple locations, the measurement system shall be
designed to use separate sampling probes, lines, and pumps for
each measurement location, and a common sample gas manifold and
FIA. The sample gas manifold must be heated to prevent
condensation.
2.1.7 Organic Concentration Analyzer. An FIA with a span
value of 1.5 times the expected concentration as propane;
however, other span values may be used if it can be demonstrated
to the Administrator's satisfaction that they would provide more
accurate measurements. The system shall be capable of meeting or
exceeding the following specifications:
2.1.7.1 Zero Drift. Less than ±3.0 percent of the span
value.
i
; 2.1.7.2 Calibration Drift. Less than ±3.0 percent of the
span value.
2.1.7.3 Calibration Error. Less than ±5.0 percent of the
calibration gas value.
2.1.7.4 Response Time. Less than 30 seconds.
71
-------
2.1.8 Integrator/Data Acquisition System. An analog or
digital device or computerized data acquisition system used to
integrate the FIA response or compute the average response and
record measurement data. The minimum data sampling frequency for
computing average or integrated values is one measurement value
every 5 seconds. The device shall be capable of recording
average values at least once per minute.
2.1.9 Calibration and other Gases. Gases used for
calibration, fuel, and combustion air (if required) are contained
in compressed gas cylinders. All calibration gases shall be
traceable to National Institute of Standards and Technology
standards and shall be certified by the manufacturer to
±1 percent of the tag value. Additionally, the manufacturer of
the cylinder should provide a recommended shelf life for each
calibration gas cylinder over which the concentration does not
change more than ±2 percent from the certified value. For
calibration gas values not generally available, alternative
methods for preparing calibration gas mixtures, such as dilution
systems, may be used with the approval of the Administrator.
2.1.9.1 Fuel. The FIA manufacturer's recommended fuel
should be used. A 40 percent H2/60 percent He or
40 percent H2/60 percent N2 gas mixture is recommended to avoid
an oxygen synergism effect that reportedly occurs when oxygen
concentration varies significantly from a mean value.
72
-------
2.1.9.2 Carrier Gas. High purity air with less than 1 ppm
of organic material (propane or carbon equivalent) or less than
0.1 percent of the span value, whichever is greater.
2.1.9.3 FIA Linearity Calibration Gases. Low-, mid-, and
high-range gas mixture standards with nominal propane
concentrations of 20-30, 45-55, and 70-80 percent of the span
value in air, respectively. Other calibration values and other
span values may be used if it can be shown to the Administrator's
satisfaction that more accurate measurements would be achieved.
i
2.1.10 Particulate Filter. An in-stack or an out-of-stack
glass fiber filter is recommended if exhaust gas particulate
loading is significant. An out-of-stack filter must be heated to
prevent any condensation unless it can be demonstrated that no
condensation occurs.
i
< 2.2 Fugitive Emissions Volumetric Flow Rate.
2.2.1 Flow Direction Indicators. Any means of indicating
inward or outward flow, such as light plastic film or paper
streamers, smoke tubes, filaments, and sensory perception.
2.2.2 Method 2 or 2A Apparatus. For determining volumetric
flow rate. Anemometers or similar devices calibrated according
to the manufacturer's instructions may be used when low
velocities are present. Vane anemometers (Young-maximum response
propeller), specialized pitots with electronic manometers (e.g.,
Shortridge Instruments Inc., Airdata Multimeter 860) are
commercially available with measurement thresholds of 15 and
8 mpm (50 and 25 fpm), respectively.
73
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2.2.3 Method 3 Apparatus and Reagents. For determining
molecular weight of the gas stream. An estimate of the molecular
weight of the gas stream may be used if approved by the
Administrator.
2.2.4 Method 4 Apparatus and Reagents. For determining
moisture content, if necessary.
2.3 Building Enclosure. The criteria for an acceptable BE
are specified in Method 204.
3. Determination of Volumetric Flow Rate of Fugitive
Emissions
3.1 Preliminary Determinations. The following points are
conconsidered exhaust points and should be measured for
volumetric flow rates and VOC concentrations:
3.1.1 Forced Draft Openings. Any opening in the facility
with an exhaust fan. Determine the volumetric flow rate
according to Method 2.
3.1.2 Roof Openings. Any openings in the roof of a facility
which does not contain fans are considered to be exhaust points.
Determine volumetric flow rate from these openings. Use the
appropriate velocity measurement devices (e.g., propeller
anemometers).
3.2 Determination of Flow Rates.
3.2.1 Measure the volumetric flow rate at all locations
identified as exhaust points in Section 3.1. Divide each exhaust
opening into nine equal areas for rectangular openings and into
eight equal areas for circular openings.
74
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3.2.2 Measure the velocity at each site at least once every
hour during each sampling run using Method 2 or 2A, if
applicable, or using the low velocity instruments in
Section 2.2.2.
4. DETERMINATION OF VOC CONTENT OF FUGITIVE EMISSIONS
4.1 Analysis Duration. Measure the VOC responses at each
fugitive emissions point during the entire test run or, if
applicable, while the process is operating. If there are
multiple emissions locations, design a sampling system to allow a
i
single FIA to be used to determine the VOC responses at all
sampling locations.
4.2 Gas VOC Concentration.
1 4.2.1 Assemble the sample train as shown in Figure 204E-1.
Calibrate the FIA and conduct a system check according to the
procedures in Sections 5.1 and 5.3, respectively.
4.2.2 Install the sample probe so that the probe is
centrally located in the stack, pipe, or duct, and is sealed
i
tightly at the stack port connection.
4.2.3 Inject zero gas at the calibration valve assembly.
Allow the measurement system response to reach zero. Measure the
system response time as the time required for the system to reach
the effluent concentration after the calibration valve has been
returned to the effluent sampling position.
4.2.4 Conduct a system check before, and a system drift
check after, each sampling run according to the procedures in
Sections 5.2 and 5.3. If the drift check following a run
75
-------
indicates unacceptable performance (see Section 5.3), the run is
not valid. The tester may elect to perform drift checks during
the run, not to exceed one drift check per hour.
4.2.5 Verify that the sample lines, filter, and pump
temperatures are 120 ± 5°C.
4.2.6 Begin sampling at the start of the test period and
continue to sample during the entire run. Record the starting
and ending times, and any required process information, as
appropriate. If multiple emission locations are sampled using a
single FIA, sample at each location for the same amount of time
(e.g., 2 minutes) and continue to switch from one location to
another for the entire test run. Be sure that total sampling
time at each location is the same at the end of the test run.
Collect at least four separate measurements from each sample
point during each hour of testing. Disregard the response
measurements at each sampling location until 2 times the response
time of the measurement system has elapsed. Continue sampling
for at least 1 minute, and record the concentration measurements.
4.3 Alternative Procedure. The direct interface sampling and
analysis procedure described in Section 7.2 of Method 18 may be
used to determine the gas VOC concentration. The system must be
designed to collect and analyze at least one sample every
10 minutes.
5. CALIBRATION AND QUALITY ASSURANCE
5.1 FIA Calibration and Linearity Check. Make necessary
adjustments to the air and fuel supplies for the FIA and ignite
76
-------
the burner. Allow the FIA to warm up for the period recommended
by the manufacturer. Inject a calibration gas into the
measurement system and adjust the back-pressure regulator to the
value required to achieve the flow rates specified by the
manufacturer. Inject the zero- and the high-range calibration
gases, and adjust the analyzer calibration to provide the proper
responses. Inject the low- and mid-range gases and record the
responses of the measurement system. The calibration and
linearity of the system are acceptable if the responses for all
four gases are within 5 percent of the respective gas values. If
the performance of the system is not acceptable, repair or adjust
the system and repeat the linearity check. Conduct a calibration
and linearity check after assembling the analysis system and
af^er a major change is made to the system.
5.2 Systems Drift Checks. Select the calibration gas that
most closely approximates the concentration of the captured
emissions for conducting the drift checks. Introduce the zero
and calibration gases at the calibration valve assembly and
verify that the appropriate gas flow rate and pressure are
present at the FIA. Record the measurement system responses to
the zero and calibration gases. The performance of the system is
i
acceptable if the difference between the drift check measurement
and the value obtained in Section 5.1 is less than 3 percent of
i
the span value. Conduct a system drift check at the end of each
run.
77
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5.3 System Check. Inject the high-range calibration gas at
the inlet of the sampling probe and record the response. The
performance of the system is acceptable if the measurement system
response is within 5 percent of the value obtained in Section 5.1
for the high-range calibration gas. Conduct a system check
before each test run.
5.4 Audits.
5.4.1 Analysis Audit Procedure. Immediately before each
test, analyze an audit cylinder as described in Section 5.2. The
analysis audit must agree with the audit cylinder concentration
within 10 percent.
5.4.2 Audit Samples and Audit Sample Availability. Audit
samples will be supplied only to enforcement agencies for
compliance tests. The availability of audit samples may be
obtained by writing:
Source Test Audit Coordinator (STAC) (MD-77B)
Quality Assurance Division
Atmospheric Research and Exposure Assessment Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
or by calling the STAC at (919) 541-7834. The request for the
audit sample roust be made at least 30 days prior to the scheduled
compliance sample analysis.
5.4.3 Audit Results. Calculate the audit sample
concentration according to the calculation procedure described in
the audit instructions included with the audit sample. Fill in
the audit sample concentration and the analyst's name on the
78
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audit response form included with the audit instructions. Send
one copy to the EPA Regional Office or the appropriate
enforcement agency, and a second copy to the STAC. The EPA
Regional Office or the appropriate enforcement agency will report
the results of the audit to the laboratory being audited.
Include this response with the results of the compliance samples
in relevant reports to the EPA Regional Office or the appropriate
enforcement agency.
, 6. NOMENCLATURE
COH = average measured concentration for the drift check
calibration gas, ppm propane.
CDO = average system drift check concentration for zero
concentration gas, ppm propane.
Cp. = corrected average VOC concentration of fugitive
emissions at point j, ppm propane.
1 CH = actual concentration of the drift check calibration
gas, ppm propane.
i
C. = uncorrected average VOC concentration measured at
point j, ppm propane.
FB = total VOC content of fugitive emissions from the
building, kg.
i
K, = 1.830 x lO'6 kg/(m3-ppm).
n = number of measurement points.
QF. = average effluent volumetric flow rate corrected to
\ standard conditions at fugitive emissions point j,
m3/min.
6f = total duration of CE sampling run, min.
7. CALCULATIONS
7.1 Total VOC Fugitive Emissions from the Building.
79
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Eq. 204E-1
7.2 VOC Concentration of the Fugitive Emissions at Point j.
CFj = (Cj - CDO) °H Eq. 204E-2
~
80
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TEPLONIIEAD
SAMPLE PUMP
-A
o
-co
o
ID
o
2
ot
o
III
SAMPLE
BYPASS
nOMME'lEMl I f—
BACK
PRESSURE
REGULATOR
EXHAUST
ANAi.Yznn
GAS INJECTION
VALVE
CXI
CONTROL
VALVE ®
FUGITIVE EMISSION POINT 1
FUGITIVE EMISSION POINT 2
FUGITIVE EMISSION POINT 3
FUGITIVE EMISSION POINT 4
FUGITIVE EMISSION POINT 5
NEEDLE
VALVES
SAMPLING
MANIFOLD
nOTAMETERS
THREE
WAY
VALVES
DA IA
AGOUISmON
SYSTIfM
ri AMI;
lONI^AIION
ANAI Y/TI1
Figure 204E-1. Tugitive emissions measurement system.
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DEC 14 •:-
METHOD 204F—VOLATILE ORGANIC COMPOUNDS CONTENT IN LIQUID
INPUT STREAM (DISTILLATION APPROACH)
1. INTRODUCTION
1.1 Applicability. This procedure is applicable for
determining the input of VOC. It is intended to be used as a
segment in the development of liquid/gas protocols for
determining VOC CE for surface coating and printing operations.
1.2 Principle. The amount of VOC introduced to the process
(L) is the sum of the products of the weight (W) of each VOC
containing liquid (ink, paint, solvent, etc.) used, and its VOC
content (V), corrected for a response factor (RF). A sample of
each coating used is distilled to separate the VOC fraction. The
distillate is used to prepare a known standard for analysis by an
FIA, calibrated against propane, to determine its RF.
1.3 Sampling Requirements. A CE test shall consist of at
least three sampling runs. Each run shall cover at least one
complete production cycle, but shall be at least 3 hours long.
The sampling time for each run need not exceed 8 hours, even if
the production cycle has not been completed. Alternative
sampling times may be used with the approval of the
Administrator.
1.4 Notes. Because this procedure is often applied in highly
explosive areas, caution and care should be exercised in
choosing, installing, and using the appropriate equipment.
Mention of trade names or company products does not constitute
endorsement. All gas concentrations (percent, ppm) are by
volume, unless otherwise noted.
82
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2. APPARATUS AND REAGENTS
2.1 Liquid Weight.
2.1.1 Balances/Digital Scales. To weigh drums of VOC
containing liquids to within 0.2 Ib.
2.1.2 Volume Measurement Apparatus (Alternative). Volume
meters, flow meters, density measurement equipment, etc., as
needed to achieve the same accuracy as direct weight
measurements.
; 2.2 Response Factor Determination (FIA Technique). The VOC
distillation system and Tedlar gas bag generation system
apparatuses are shown in Figures 204F-1 and 204F-2, respectively.
The following equipment is required:
2.2.1 Sample Collection Can. An appropriately-sized metal
can to be used to collect VOC containing materials. The can must
be constructed in such a way that it can be grounded to the
coating container.
2.2.2 Needle Valves. To control gas flow.
• 2.2.3 Regulators. For calibration, dilution, and sweep gas
cylinders.
2.2.4 Tubing and Fittings. Teflon and stainless steel
tubing and fittings with diameters, lengths, and sizes determined
i
by the connection requirements of the equipment.
2.2.5 Thermometer. Capable of measuring the temperature of
the hot water and oil baths to within 1°C.
2.2.6 Analytical Balance. To measure ±0.01 mg.
i 2.2.7 Microliter Syringe. 10-/il size.
83
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2.2.8 Vacuum Gauge or Manometer. 0- to 760-mm (0- to
30-in.) Hg U-Tube manometer or vacuum gauge.
2.2.9 Hot Oil Bath, With Stirring Hot Plate. Capable of
heating and maintaining a distillation vessel at 110 ± 3°C.
2.2.10 Ice Water Bath. To cool the distillation flask.
2.2.11 Vacuum/Water Aspirator. A device capable of drawing
a vacuum to within 20 mm Hg from absolute.
2.2.12 Rotary Evaporator System. Complete with folded inner
coil, vertical style condenser, rotary speed control, and Teflon
sweep gas delivery tube with valved inlet. Buchi Rotavapor or
equivalent.
2.2.13 Ethylene Glycol Cooling/Circulating Bath. Capable of
maintaining the condenser coil fluid at -10°C.
2.2.14 Dry Gas Meter (DGM). Capable of measuring the
dilution gas volume within 2 percent, calibrated with a
spirometer or bubble meter, and equipped with a temperature gauge
capable of measuring temperature within 3°C.
2.2.15 Activated Charcoal/Mole Sieve Trap. To remove any
trace level of organics picked up from the DGM.
2.2.16 Gas Coil Heater. Sufficient length of 0.125-inch
stainless steel tubing to allow heating of the dilution gas to
near the water bath temperature before entering the
volatilization vessel.
2.2.17 Water Bath, With Stirring Hot Plate. Capable of
heating and maintaining a volatilization vessel and coil heater
at a temperature of 100 ± 5°C.
84
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2.2.18 Volatilization Vessel. 50-ml midget impinger fitted
with a septum top and loosely filled with glass wool to increase
the volatilization surface.
2.2.19 Tedlar Gas Bag. Capable of holding 30 liters of gas,
flushed clean with zero air, leak tested, and evacuated.
2.2.20 Organic Concentration Analyzer. An FIA with a span
value of 1.5 times the expected concentration as propane;
however, other span values may be used if it can be demonstrated
that they would provide more accurate measurements. The FIA
instrument should be the same instrument used in the gaseous
analyses adjusted with the same fuel, combustion air, and sample
back-pressure (flow rate) settings. The system shall be capable
of meeting or exceeding the following specifications:
i
' 2.2.20.1 Zero Drift. Less than ±3.0 percent of the span
i
value.
2.2.20.2 Calibration Drift. Less than ±3.0 percent of the
span value.
2.2.20.3 Calibration Error. Less than ±3.0 percent of the
calibration gas value.
2.2.21 Integrator/Data Acquisition system. An analog or
digital device or computerized data acquisition system used to
integrate the FIA response or compute the average response and
record measurement data. The minimum data sampling frequency for
computing average or integrated value is one measurement value
every 5 seconds. The device shall be capable of recording
average values at least once per minute.
85
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2.2.22 Chart Recorder (Optional). A chart recorder or
similar device is recommended to provide a continuous analog
display of the measurement results during the liquid sample
analysis.
2.2.23 Zero Air. High purity air with less than 1 ppm of
organic material (as propane) or less than 0.1 percent of the
span value, whichever is greater. Used to supply dilution air
for making the Tedlar bag gas samples.
2.2.24 THC Free N2. High purity N2 with less than
1 ppm THC. Used as sweep gas in the rotary evaporator system.
2.2.25 Calibration and other Gases. Gases used for
calibration, fuel, and combustion air (if required) are contained
in compressed gas cylinders. All calibration gases shall be
traceable to National Institute of Standards and Technology
standards and shall be certified by the manufacturer to
±1 percent of the tag value. Additionally, the manufacturer of
the cylinder should provide a recommended shelf life for each
calibration gas cylinder over which the concentration does not
change more than ±2 percent from the certified value. For
calibration gas values not generally available, alternative
methods for preparing calibration gas mixtures, such as dilution
systems, may be used with prior approval of the Administrator.
2.2.25.1 Fuel. The FIA manufacturer's recommended fuel
should be used. A mixture of 40 percent H2/60 percent He, or
40 percent HE/60 percent N2 is recommended to avoid fuels with
86
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oxygen to avoid an oxygen synergism effect that reportedly occurs
when oxygen concentration varies significantly from a mean value.
2.2.25.2 Combustion Air. High purity air with less than
1 ppm of organic material (as propane) or less than 0.1 percent
of the span value, whichever is greater.
2.2.25.3 FIA Linearity calibration Gases. Low-, mid-, and
high-range gas mixture standards with nominal propane
concentration of 20-30, 45-55, and 70-80 percent of the span
value in air, respectively. Other calibration values and other
span values may be used if it can be shown that more accurate
measurements would be achieved.
2.2.25.4 System Calibration Gas. Gas mixture standard
containing propane in air, approximating the VOC concentration
expected for the Tedlar gas bag samples.
3. DETERMINATION OF LIQUID INPUT WEIGHT
3.1 Weight Difference. Determine the amount of material
introduced to the process as the weight difference of the feed
material before and after each sampling run. In determining the
total VOC containing liquid usage, account for: (a) the initial
(beginning) VOC containing liquid mixture; (b) any solvent added
during the test run; (c) any coating added during the test run;
and (d) any residual VOC containing liquid mixture remaining at
the end of the sample run.
3.1.1 Identify all points where VOC containing liquids are
introduced to the process. To obtain an accurate measurement of
87
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VOC containing liquids, start with an empty fountain (if
applicable). After completing the run, drain the liquid in the
fountain back into the liquid drum (if possible), and weigh the
drum again. Weigh the VOC containing liquids to ±0.5 percent of
the total weight (full) or ±0.1 percent of the total weight of
VOC containing liquid used during the sample run, whichever is
less. If the residual liquid cannot be returned to the drum,
drain the fountain into a preweighed empty drum to determine the
final weight of the liquid.
3.1.2 If it is not possible to measure a single
representative mixture, then weigh the various components
separately (e.g., if solvent is added during the sampling run,
weigh the solvent before it is added to the mixture). If a fresh
drum of VOC containing liquid is needed during the run, then
weigh both the empty drum and fresh drum.
3.2 Volume Measurement (Alternative). If direct weight
measurements are not feasible, the tester may use volume meters
and flow rate meters (and density measurements) to determine the
weight of liquids used if it can be demonstrated that the
technique produces results equivalent to the direct weight
measurements. If a single representative mixture cannot be
measured, measure the components separately.
4. DETERMINATION OF VOC CONTENT IN INPUT LIQUIDS
4.1 Collection of Liquid Samples.
4.1.1 Collect a 1-pint or larger sample of the VOC
containing liquid mixture at each application location at the
88
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beginning and end of each test run. A separate sample should be
taken of each VOC containing liquid added to the application
mixture during the test run. If a fresh drum is needed during
the sampling run, then obtain a sample from the fresh drum.
4.1.2 When collecting the sample, ground the sample
container to the coating drum. Fill the sample container as
close to the rim as possible to minimize the amount of headspace.
4.1.3 After the sample is collected, seal the container so
the sample cannot leak out or evaporate.
4.1.4 Label the container to identify clearly the contents.
4.2 Distillation of VOC.
4.2.1 Assemble the rotary evaporator as shown in
Figure 204F-1.
4.2.2 Leak check the rotary evaporation system by aspirating
a Vacuum of approximately 20 mm Hg from absolute. Close up the
system and monitor the vacuum for approximately 1 minute. If the
vacuum falls more than 25 mm Hg in 1 minute, repair leaks and
repeat. Turn off the aspirator and vent vacuum.
4.2.3 Deposit approximately 20 ml of sample (inks, paints,
etc.) into the rotary evaporation distillation flask.
4.2.4 Install the distillation flask on the rotary
evaporator.
4.2.5 Immerse the distillate collection flask into the ice
water bath.
4.2.6 Start rotating the distillation flask at a speed of
approximately 30 rpm.
89
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4.2.7 Begin heating the vessel at a rate of 2 to 3°C per
minute.
4.2.8 After the hot oil bath has reached a temperature of
50°C or pressure is evident on the mercury manometer, turn on the
aspirator and gradually apply a vacuum to the evaproator to
within 20 mm Hg of absolute. Care should be taken to prevent
material burping from the distillation flask.
4.2.9 Continue heating until a temperature of 110°C is
achieved and maintain this temperature for at least 2 minutes, or
until the sample has dried in the distillation flask.
4.2.10 Slowly introduce the N2 sweep gas through the purge
tube and into the distillation flask, taking care to maintain a
vacuum of approximately 400-mm Hg from absolute.
4.2.11 Continue sweeping the remaining solvent VOC from the
distillation flask and condenser assembly for 2 minutes, or until
all traces of condensed solvent are gone from the vessel. Some
distillate may remain in the still head. This will not affect
solvent recovery ratios.
4.2.12 Release the vacuum, disassemble the apparatus and
transfer the distillate to a labeled, sealed vial.
4.3 Preparation of VOC standard bag sample.
4.3.1 Assemble the bag sample generation system as shown in
Figure 204F-2 and bring the water bath up to near boiling
temperature.
4.3.2 Inflate the Tedlar bag and perform a leak check on the
bag.
90
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4.3.3 Evacuate the bag and close the bag inlet valve.
4.3.4 Record the current barometric pressure.
4.3.5 Record the starting reading on the dry gas meter, open
the bag inlet valve, and start the dilution zero air flowing into
the Tedlar bag at approximately 2 liters per minute.
4.3.6 The bag sample VOC concentration should be similar to
the gaseous VOC concentration measured in the gas streams. The
amount of liquid VOC required can be approximated using equations
in Section 6. Using Equation 204F-4, calculate Cvoc by assuming
RF is 1.0 and selecting the desired gas concentration in terms of
propane, CC3. Assuming Bv is 20 liters, ML, the approximate
amount of liquid to be used to prepare the bag gas sample, can be
calculated using Equation 204F-2.
4.3.7 Quickly withdraw an aliquot of the approximate amount
calculated in Section 4.3.6 from the distillate vial with the
microliter syringe and record its weight from the analytical
balance to the nearest 0.01 mg.
4.3.8 Inject the contents of the syringe through the septum
of the volatilization vessel into the glass wool inside the
vessel.
4.3.9 Reweigh and record the tare weight of the now empty
syringe.
4.3.10 Record the pressure and temperature of the dilution
gas as it is passed through the dry gas meter.
91
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4.3.11 After approximately 20 liters of dilution gas have
passed into the Tedlar bag, close the valve to the dilution air
source and record the exact final reading on the dry gas meter.
4.3.12 The gas bag is then analyzed by FIA within 1 hour of
bag preparation in accordance with the procedure in Section 4.4.
4.4 Determination of VOC response factor.
4.4.1 Start up the FIA instrument using the same settings as
used for the gaseous VOC measurements.
4.4.2 Perform the FIA analyzer calibration and linearity
checks according to the procedure in Section 5.1. Record the
responses to each of the calibration gases and the back-pressure
setting of the FIA.
4.4.3 Connect the Tedlar bag sample to the FIA sample inlet
and record the bag concentration in terms of propane. Continue
the analyses until a steady reading is obtained for at least
30 seconds. Record the final reading and calculate the RF.
4.5 Determination of coating VOC content as VOC (Vu).
4.5.1 Determine the VOC content of the coatings used in the
process using EPA Method 24 or 24A as applicable.
5. CALIBRATION AND QUALITY ASSURANCE
5.1 FIA Calibration and Linearity Check. Make necessary
adjustments to the air and fuel supplies for the FIA and ignite
the burner. Allow the FIA to warm up for the period recommended
by the manufacturer. Inject a calibration gas into the
measurement system and adjust the back-pressure regulator to the
92
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value required to achieve the flow rates specified by the
manufacturer. Inject the zero- and the high-range calibration
gases and adjust the analyzer calibration to provide the proper
responses. Inject the low- and mid-range gases and record the
responses of the measurement system. The calibration and
linearity of the system are acceptable if the responses for all
four gases are within 5 percent of the respective gas values. If
the performance of the system is not acceptable, repair or adjust
the system and repeat the linearity check. Conduct a calibration
and linearity check after assembling the analysis system and
after a major change is made to the system. A calibration curve
consisting of zero gas and two calibration levels must be
performed at the beginning and end of each batch of samples.
5.2 Systems Drift Checks. After each sample, repeat the
system calibration checks in Section 5.1 before any adjustments
to the FIA or measurement system are made. If the zero or
calibration drift exceeds ±3 percent of the span value, discard
the result and repeat the analysis.
5.3 Quality Control. A minimum of one sample in each batch
must be distilled and analyzed in duplicate as a precision
control. If the results of the two analyses differ by more than
±10 percent of the mean, then the system must be reevaluated and
the entire batch must be re-distilled and analyzed.
5.4 Audits.
5.4.1 Audit Procedure. Concurrently, analyze the audit
sample and a set of compliance samples in the same manner to
93
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evaluate the technique of the analyst and the standards
preparation. The same analyst, analytical reagents, and
analytical system shall be used both for compliance samples and
the EPA audit sample. If this condition is met, auditing of
subsequent compliance analyses for the same enforcement agency
within 30 days is not required. An audit sample set may not be
used to validate different sets of compliance samples under the
jurisdiction of different enforcement agencies, unless prior
arrangements are made with both enforcement agencies.
5.4.2 Audit Samples. Audit Sample Availability. Audit
samples will be supplied only to enforcement agencies for
compliance tests. The availability of audit samples may be
obtained by writing:
Source Test Audit Coordinator (STAC) (MD-77B)
Quality Assurance Division
Atmospheric Research and Exposure Assessment Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
or by calling the STAC at (919) 541-7834. The request for the
audit sample must be made at least 30 days prior to the scheduled
compliance sample analysis.
5.4.3 Audit Results. Calculate the audit sample
concentration according to the calculation procedure described in
the audit instructions included with the audit sample. Fill in
the audit sample concentration and the analyst's name on the
audit response form included with the audit instructions. Send
one copy to the EPA Regional Office or the appropriate
94
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enforcement agency, and a second copy to the STAC. The EPA
Regional Office or the appropriate enforcement agency will report
the results of the audit to the laboratory being audited.
Include this response with the results of the compliance samples
in relevant reports to the EPA Regional Office or the appropriate
enforcement agency.
6 . NOMENCLATURE
Bv = Volume of bag sample volume, liters.
CC3 = Concentration of bag sample as propane, mg/ liter.
cvoc = Concentration of bag sample as VOC, mg/ liter.
K = 0.00183 mg propane/ (liter-ppm propane)
L = Total VOC content of liquid input, kg propane.
ML = Mass of VOC liquid injected into the bag, mg.
My = Volume of gas measured by DGM, liters.
PM = Absolute DGM gas pressure, mm Hg.
PSTO = Standard absolute pressure, 760 mm Hg.
FIA reading for bag gas sample, ppm propane.
RF = Response factor for VOC in liquid,
weight VOC/weight propane.
RFj = Response factor for VOC in liquid J,
weight VOC/weight propane.
TM = DGM temperature, °K.
TSTD = Standard absolute temperature, 293 °K.
Vu = Initial VOC weight fraction of VOC liquid J.
VFJ = Final VOC weight fraction of VOC liquid J.
VAJ = VOC weight fraction of VOC liquid J added during the
run.
95
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Wjj = Weight of VOC containing liquid J at beginning of
run, kg.
WFJ = Weight of VOC containing liquid J at end of run, kg.
WAJ = Weight of VOC containing liquid J added during the
run, kg.
7. CALCULATIONS
7.1 Bag sample volume.
Mv TSTD PM
v " T P
i *
Eq. 204F-1
7.2 Bag sample VOC concentration.
_ML
-voc
Eq. 204F-2
7.3 Bag sample VOC concentration as propane.
7.4
7.5
~ R
Response Factor.
Eq. 204F-3
Total VOC Content of the Jnput VOC Containing Liquid.
RF = -^ Eq. 204F-4
T =
Fj +
'AJ WAJ
RF,
Eq. 204F-5
96
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CO
f\J
Z
UJ
TTT1 I
CONDENSER
TEFLON
PURGE TUBE
0-30 HG
MANOMETER
DISTILLATION
FLASK
OIL
TEMPERATURE
PROBE
_HOT OIL
BATH
STIRRING
ETHYLENE GLYCOL
COOLING/CIRCULATING
BATH
DISTILLATE
COLLECTION
FLASK
TO
ASPIRATOR
ROTARY.
EVAPORATOR
FLASK w/
TUBULAT ION
Figure 204F-1. VOC distillation system apparatus.
-------
cc
o
o:
UJ
M
CO
00
Q
UJ
UJ
-
U-TUBE
'MANOMETER
EDLAR BAG
30 LITER
JU-SYR INGE
I
METER OUTLET
EMPPER^URE VOLATILIZATION
rKUdL VESSEL
^ACTIVATED
CHARCOAL-
MOLECULAR
SIEVE
{XJ-
CAPACITY
WATER BATH
TEMPERATURE
PROBE
GLASS WOOL
-S.S. GAS
HEATING COIL
HOT WATER
BATH
STIR RING
HOTPLATE
Ficjure 204F-2. Tcdlar gas bag generation system apparatus.
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