-------
Energy Dispersive X-Ray Fluorescence Analysis of Air Filters
Finally, che corrected counts are divided by analysis live time, L,
to obtain the count rate,
T.
and OI. ,
1 L
Calculations for instrument calibration are similar except that C.
is solved for in eq . 3. Also, since single element and non- interfering
multi-element standards are used for calibration, spectral corrections are
no t made and T . • M and aT = aN ,
11 i i
7 . Quality Control
The filters are loaded and unloaded into specially machined
acrylic holders. Filter loading is done in the laminar flow hood and the
filters themselves are handled with forceps, out of che analysis and
deposit area. The loaded filters are transported to and from the TEFA in
covered sample cases, and the filter holders are cleaned between each use.
These procedures prevent the possibility of sample contamination.
To prevent confusion in identification of the samples when they
are out of their ID coded filter containers, a sample position number versus
ID number relationship used. This relationship is established by the XRF LOG
before the filters are removed from their containers and it is verified after
each handling step in che procedure.
For each XRF analysis batch of 10 samples, one blank and a quality
control standard is analyzed. Measured concentrations of the quality control
standard, which contains several key elements, are compared with actual
concentrations (Figure 4). If che deviacion is more chan T 2%, all samples
of that run must be reanalyzed. The results of che quality control standard
over a number of runs provides a measure of the XRF analysis precision. If che
results show a trend in drift, recalibration is required.
Several elements, including K, Ca, Fe , As, Br and ?b are measured
under more than one of the three excitation conditions normally used for each
run. Results of these elements are compared for each of the excitation
conditions under which they are measured. If agreement is for outside the
calculated uncertainties, che sample must be reanalyzed.
(Rev. August, 1981)
-------
ERROR
•p
r~
•IT
J. it .
44 !
4- .
.i
L MEA3! i
•";,') 4J. ~o.j __
•-•'•' 4J." :-:=•, -r-
--
- <'> . 4
T T
r.p
rr
MT
rONCENTRATION
ACTUAL MEASURED
4<'i - xi'j 4 5 . 25-i~ ? . O
4 4.. •-;<•/ 44. 92*- 2.2
44.90 4?;. (•)•=>•(— 2.2
4T. -;O 4/-..94T-- 2 .:"»''
44.xO 44.i::(")H — •?.2
V. ERROR
1. 1
i 1.4
0. 4
CONCENTRATION' •/ ERROR
ACTUAL MEASURED
AT.. :=:i') 4O . •:>•:>.+._ •-•. 0,4. r:,. =;
44 . •-:<•> 44 . •-'•='•+— 2 . 2A. 1 . ••-•
44. •:•(-, 45. .-;•:>+_ 2. 23 i.l
47. ":'.") 47. 03n— l!. ::••-. — '"'. ?
44'. ;5'"i 44. '^V4-*-— 2. 1)5
4--'. 7'j 4'r'. 42-i— 2. 32
pr FA:;.T ! 1
ift ^TANDAPD iTl'?(")43
| r.riMf.ENTPATTON V. ERROR
ACTUAL riEAil.iPED
T 41-,. ;=•{•.! 40.'"'1H— '.";.'Il=:. '"'.::
=1 44 . .":'") 44 . ^7 -i— *'. *"": •"). .--.
=• 4J.. •:•!•) 4!=:.'"•":-!— 2.27 <"'..!:
T 4-.^('i 47 . ••"I'Tn— I:. V-. - •">.=;
RP''P
J./'.
44,
(Rev. August, L9B1)
-------
Energy Dispersive X-Ray Fluorescence Analysis of Air Filters
8. Quality Assurance
Calibration of the instrument is by thin film standards prepared
by Micromatter, Inc., Eastsound, WA. , and by solution deposited and
particle standards made by Columbia Scientific Industries, Austin, TX.
Plots of instrument response versus atomic number should yield smooth
curves, and are used to validate standard concentrations.
Interlaboratory comparisons are used Co check accuracy of the
instrument calibration. Several techniques have been used in interlaboratory
comparisons in addition to energy dispersive x-ray fluorescence, including
neutron activation analysis, optical spectroscopy, wavelength dispersive
x-ray fluorescence, and ion chromocography.
In house intermethod comparison vith neutron activation analysis is
done routinely. This independent method provides comparison with SRF on
about 20 elements.
Results from each analysis run are reviewed by the laboratory super-
visor. The inter-excitation and quality control standard results are checked
as described in section 7. The laboratory supervisor must initial the
XRF LOG before results of that run are considered valid. Periodic audits
of the TEFA startup, filter loading and unloading, analysis, and TErA
shutdown procedures insure compliance with the Standard Operating Procedure.
(Rev. August, 1981)
-------
-------
QUALITY ASSURANCE PLAN
(ORGANIC AND ELEMENTAL CARBON ANALYSIS)
1. QA Objectives in Terras of Precision, Accuracy, Completeness, Representa-
tiveness , and Comparability.
a. Precision. Replicate measurements of organic, elemental, and carbon-
ate carbon should correspond to a standard deviation of ±15%.
b. Accuracy. Analyses will be expected to be accurate to within ±152.
c. Completeness. Analytical results will be obtained for essentially
all samples delivered to OGC.
d. Representativeness. Not applicable,
e. Comparability. All data will be reported in yg of carbon per m^ of
air at 25*C and 760 mm.
2, Sample Custody.
Mr. Cliff Frazier will be responsible for the custody of the
samples.
s,
3. Calibration Procedures and Frequency.
Calibration is accomplished in two ways. At the end of each run a
known amount of CH^ gas is injected into the oven and the response measured.
Thus, a single point calibration is included in every run. The second cali-
bration procedure involves the measurement of filter samples containing known
amounts of specific carbonaceous materials. This will be done on a monthly
basis.
4 Analytical Procedures.
The initial configuration of the carbon analyzer was conceptually sin-
pie. An aerosol sample on a glass or quartz fiber filter segment was heated
to 600"C in a He atmosphere for the purpose of volatilizing organic carbon.
-------
The volatilized organic carbon was oxidized Co C02 in a MnC>2 bed at 900"C,
reduced to CHi» and measured by a flame ionization detector (FID). Elemental
carbon was measured by introducing 02 into the sample oven and combusting the
carbon to C02 which was measured as above. Early in the project a difficulty
in this method of speciation was discovered; namely, during the organic anal-
ysis a fraction cf the organic carbon was pyrolytically converted to elemen-
tal carbon. This was manifested by an increase in the "blackness" of the fil-
ter at the end of the organic analysis. The degree of pyrolytic conversion
was variable and could not be related in any simple manner to measurable prop-
erties of the sample.
To overcome this difficulty, the system which is now in use was de-
veloped. It involves modifications in the combustion method itself, the ad-
dition of an optical system for the continuous monitoring of filter reflec-
tivity, and the automation of the analytical sequence by microprocessor tech-
nology. The system is shown schematically in Figures 1 and 2 . As described
below, the optical system is used to correct for the pyrolytic conversion of
organic to elemental carbon.
In th? combustion method which is currently in use, the filter segments
to be analyzed are placed in thfe quartz sample boat, the combustion zone tem-
perature set to 350°C, and the oven purged with an 02(2%)-He(98%) mixture. The
boat is then inserted into the combustion zone in which oxidation and volatili-
zation of organic carbon into the flowing 02-He stream occur. The volatilized
carbon is oxidized to C02 in tho Mn02 bed, reduced to CH»,, and measured as de-
scribed above. This step typically removes about 2/3 of the organic carbon. On
the basis of the reflectivity measurements no net oxidation of elemental carbon
occurs, and conversion of organic to elemental carbon is minimized during this
-------
Vent
r— Loc
cv[xh —
GSV|Xh-- -
He
or
He/02
153 Val
iding Heating 0
JL
xiaation |2\J 1
T.. . A
i ivv 1
-i i 1
j u
[Temperature 2
Control ~{
i
L _ —
ve
micro-
—- nrnrps^or
LI
i
i
Methanator
c" T r\
r ID
l
Electrometer
i
Integrator
i
Recorder
Figure 1 Block diagran of the carbon analyzer.
-------
Si photo cell
Pin hole
Quartz light tube
2 x 3mm oval mirror \
Sample boat
Lenses "L
632.8nm
interference
filter
Oven
\
To
microprocessor
Oxidation zone (Mn
He/Ne laser
Gas linoi
\
Figure 2. Combustion oven and optical system.
-------
step. The latter is apparently inhibited by the oxygen in the carrier gas. The
sample oven is then purged with heliun such that all oxygen is removed from the
oven. During this process the sample remains in the oven, and the oven tempera-
ture is maintained at 350*C. When purging is complete, the combustion zone tem-
perature is raised to 600*C, and the remaining organic carbon is volatilized
into the helium carrier gas. This carbon is measured as above.
For the measurement of elemental carbon the combustion zone tecperature
is dropped to 400'C following which the carrier gas is changed to 02(2%)-He
(98*). The sample remains in the oven during this process. After 100 seconds
under these conditions, the temperature is raised to 500°C where it is held
•
for 120 seconds and finally to 600*C where it is held for 200 seconds. During
this step-wise combustion the evolved C02 is measured as usual. The purpose
of the step-wise combustion is to facilitate the pyrolysis correction.
Throughout the combustion process the reflectivity of the filter sample
is continuously monitored by a 633 nm He-Ne laser system. The time course of
the reflectivity is shown in Figure 3. At 350°C in 02/He little change in the
reflectivity is observed, indicating no net oxidation of elemental carbon or py-
rolytic conversion of organic to elemental carbon. As the temperature is raised
to 600°C in He, however, the reflectivity decreases, indicating an increase in
elemental carbon. The step-wise combustion of elemental carbon in the third
phase of the analysis results in an increase in the reflectivity corresponding
to the oxidation of elemental carbon. The pyrolysis correction is determined
by measuring the amount of elener.tal carbon oxid-ation necessary to return the
filter reflectivity to the value it had before pyrolysis occurred. The shaded
area in Figure 3b corresponds to the pyrolysis correction.
-------
Figure 3 (a) Filter reflectivity as a function of time.
(b) FID output as a function of time.
The cross-hatched section of the 400-500-600*C 02/He peak
corresponds to the correction for the pyrolytic production
of elemental carbon.
143.9
1
-I
J
U
hi
H
a
O
29.63
isee.
1290.
833.8
^^—t
350 *C
02/H«
600*C/He
400"[C
600*C
Cilibrition
12S3.
1
-i
J
I
1
-l
J
2960.
• Figure 3
-------
The analytical system is under the control of a microcomputer built
around a Motorola 6802 microprocessor. All switching of gas flovs, timing,
temperature control, pyrolysis correction, analog to digital conversion elec-
tronics, electrometer functions, signal integration, data stqrage, and data
outputs are controlled by the computer system. All data (7ID output, reflec-
tivity, combustion zone temperature, integrated peak areas, pyrolysis correc-
tion, and time) are stored on a cassette tape which can be analyzed at a later
date on the OGC PRIME 350 computer. The only operator interaction during the
analysis is to enter the filter identification code into the microcomputer
and load the sample into the system.
5. Data Analysis, Validation, and Reporting.
Data will be recorded on both cassette magnetic tape and on the x-y
plot generated at the time of analysis. The data stored on the tape are pro-
cessed by the OGC PRIME 350 computer. The processing involves peak integra-
tion, blank subtraction, pyrolysis correction, and conversion to scientific
units. The master equation 1s:
„/
UgC/zn
(peak area) / *ass of carbon \ .
?calibration\ X ln calibration 1 x f -^-
I \ PfiSK /
a /
\peak area / segment analyzed
- blank (ygC/c^) x total area of filter
' volume of air sampled
In this equation "peak area" has already been corrected for pyrolysis as de-
scribed in Section 4.
Several criteria will be used to validate an individual analysis. The
'first concerns the shape of the calibration peak. If injection of the CH^ cal-
ibration gas results in two peaks, this is indicative of incomplete oxidation
-------
in the Mn02 oxidation zone. If this is observed, then the oven must be re-
packed with fresh MnO^. The second criterion concerns the magnitude of the cal-
' ibration peak. If this is significantly low ( £ 15Z with respect to the aver-
age) or shows a decreasing trend, a loss of efficiency in the methanation pro-
cess is indicated. This can be corrected by re-packing the methanator with
fresh Ni/firebrick. The trend of calibration peak areas will be checked at
the end of each analysis day, and relevant comments entered in a QA log book.
Finally, an optical absorption measurement of each filter will be made to val-
idate the elemental carbon measurement. Absorption will be plotted as a func-
tion of measured elemental carbon concentration (ygC/cm2). Obvious outliers
will be re-analyzed.
The data flow in this program is almost totally automated. The out-
put of the carbon analyzer is recorded on a cassette magnetic tape which is
processed on the OGC PRBffi 350 computer. The only operator interaction is to
enter filter codes and air volumes into the computer file. This information
will be checked for accuracy from a hard-copy printout. Emily Heyerdahl will
be primarily responsible for handling this data flow.
6. Internal Quality Control Checks.
a. Standard filter. At the beginning of each day a "standard filter"
will be analyzed. The "standard filter" is an actual high volume fil-
ter sample collected in Portland, Oregon. Many analyses have been made
from this filter. If the standard filter analysis differs from the av-
erage by -z-z than 2 stizdard deviations, the standard filter will be
re-analyzed. If the re-analysis is within the above limit, then rou-
tine analysis will proceed. If not, the cause of the problem will be
investigated and corrected.
-------
b. Calibration. Each run will be individually calibrated. As discussed
in Section 5 , the shape and magnitude of the calibration peak relate
to the.analytical efficiency. In addition, at the Beginning of
each day CHj, calibrations are performed in both He and He/02 car-
rier gases. If these do not agree to within 102, the source of
•>
the discrepancy will be investigated and corrected.
c. External Standards. Filter segments containing known amounts of or-
ganic, elemental, or carbonate carbon will be analyzed once each month.
These will be prepared by Richard Johnson and submitted blind to Isiily
Heyerdahl who will analyze them.
" ~^' Performance and System Audits.
This is accomplished by the actions of Sections 5 and &.
8. Preventive Maintenance.
The primary components requiring preventive maintenance are the oxi-
dation and methanation ovens ard the optical system. The diagnostic tests and
maintenance procedures for the i7ens were discussed in Section 5 . in the op-
tical system the light pipe between the oxidation oven and the detector occa-
sionally deteriorates with respect to light transmission. This is manifested
by an apparent decrease in reflected light from a blank filter. When this oc-
curs, the only remedy is to replace the light pipe.
9. Specific Procedures to Be Used to Routinely Assess Data Precision, Accuracy,
and completeness.
Precision will be assessed in two ways. As discussed in Section 7 , a
"standard filter" is analyzed at the beginning of each day. These standard fil-
ter analyses are tabulated and stored in a computer file. The standard deviations
-------
10
for organic, elemental, and carbonate carbon will be calculated in the usual man-
ner. In addition, replicate analyses are performed on approximately one out of
ten filters. The absolute differences (as vgC/cm2) between the analyses will be
tabulated and stored in a computer file. Standard deviations will also be calcu-
lated.
Accuracy will be determined from the monthly measurement of external
standards. In addition, interlaL-oratory comparisons will be conducted from time
to time.
10. Corrective Action.
This has been discussed in Section 5.
11• Quality Assurance Reports to Management.
The results of the analyses of the standard filters, replicate
filters, and external standards will be transmitted to Dr. John A. Cooper.
-------
Page 10
21. Plot a graph of Q, vs P on two-cycle, semi-log
graph paper to obtain the hi vol orifice calibration line
as illustrated in Figure 2.7. Use a -straight edge to draw a
best fit line through the calibration points.
22. If any calibration point does not fall within ± 1
percent of the line, rerun that point, recalculate, and replot.
The percent deviation can be calculated by taking the questionable
flowrate (Q ) and the calibration line flowrate (Q ) for the
same P reading.
. . a (Qo * Qc)
Percent Deviation =
x 100
.»
.» V.O I'.l l'.2 TTT 1.4 l.J 1.6 1.7 1.8 1.9
Flow rate (Q,), m /min
Figure 2.7 Example of hi vol orifice
calibration relationship
anot to exceed + 1 percent
(Rev. 7/14/81)
-------
Page 11
4. Sampler
Samplers must be calibrated when first purchased,
after- major maintenance on the sampler (e.g., replacement of
motor or motor brushes) , any time the flow-rate measuring
device (i.e., rotameter or recorder) has to be replaced or
repaired, or any time a one-point audit check
deviates more than + 77, from the calibration curve.
In using the orifice calibration unit to calibrate a
sampler, corrections must be made to the indicated flow rate
if the ambient barometric pressure or temperature is substan-
tially different from the pressure or temperature values
recorded when the orifice unit vj^g calibrated. Calculate the
corrected flow rate as follows :
/T P \ 1/2
where
Q2 = corrected flow rate at sampling conditions, m /min;
Q, = uncorrected flow rate read from the orifice
unit calibration curve for a given pressure,
in. H2O;
T, = absolute temperature when orifice unit was
calibrated, °K;
P, = barometric pressure when orifice unit was
calibrated, iranHg;
T- = absolute temperature while calibrating the
sampler, °K, and
?2 = barometric pressure while calibrating sampler,
mmHg.
For example, if P, = P2/ Figure 2.8 shows the percentage change
of Q versus temperature differences. If T2 is greater than
T., the percentage change is positive; if T2 is less than T^,
the percent change is negative. The same procedure is used
to correct for pressure differences. The above formula corrects
for field conditions only.
(Rev. 7/14/81)
-------
Page 13
5. Calibration of Hi Vol Sampler with Flow Recorder -
Connect the calibration equipment as shown in Figure 2-13.
All data during the initial and final calibrations for
one hi vol are recorded on the same page 'in the Hi Vol Cali-
bration Log-. if the sampler is being
calibrated for the first time or if it has been serviced,
record the data on the "Initial" section of the calibration
log. If the sampler is being calibrated prior to scheduled
maintenance, record the data under the "Final" section of
the calibration log.
The stepwise calibration procedure for this model of
Hi Vol sampler is presented below:
1. Assemble a hi vol with a clean filter and operate
it for at least 5 minutes at 115 volts. If a step-down trans-
former is used during normal operation, then calibration
should be performed with the transformer in operation.
2. Record the flow recorder number and date on three
gummed labels. Affix one gummed label to the'very top of the
metal face on the front of the flow recorder. Affix another
gummed label to the middle of the vacuum hose and affix the
last gummed label to the other side of the hi vol motor.
3. Turn the motor OFF and attach the flow recorder to
the hi vol motor.
4. Install a clean recorder chart and check the recorder
for proper operation. Zero the pen if necessary.
5. Remove the filter holder.
.6. Attach the calibrated orifice with one of the load
plates between the motor and the orifice.
7. Turn the motor ON and record the water manometer
and flow recorder readings after they stabilize.
8. Turn the motor OFF.
9. Repeat Steps 6-8 for each of the other load plates.
(Rev. 7/14/81)
-------
70
60
50
3 40
30
20-
HT^
Page 14
f r
i i l .... i
i ! i l . . I ii i i
^^r ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^>^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
0 .8 .9 1.0 1.1 1.2 1.3 1.4 1,5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3
FLOWRATE IN M3 MINUTE
Temperature
Cali
Date m^n \.
J
HI-VOL CALIBRATION CURVE
Barometric Pressure ~7£>O rr>'
Calibration log page no. \ Q _ Hi Vol. No. 5
\6. 1Q76 _ Analyst 6 .& .
Example of hi vol calibration curve
(Rev. 7/14/81)
-------
Page 15
Figure 2-13. Hi vol and orifice assembled for
calibration with flow recorder.
(Rev. 7/14/81)
-------
Page 16
10. Repeat Steps 6-9 once.
11. Determine and record the air flow rate as read from
the hi vol orifice calibration curve for each flow recorder
reading.
12. Record the barometric pressure in mm Hg and temperature
in °C.
13. Determine the percent difference between the temperature
and barometric pressure recorded and the temperature and baro-
metric pressure measured when the hi vol orifice was calibrated.
a. If the recorded barometric pressure is within
+15 percent range and the recorded temperature
is within +100 percent range proceed to step 16.
b. If the barometric pressure exceeds the +15
percent .range or the temperature exceeds the
+100 percent range or both occur proceed to
step 14.
14. Convert the temperature measured when the hi vol orifice
was calibrated (T,) and the temperature recorded in Step 12
above (T2) to absolute temperature (°K).
15. Determine the true flow rates corrected to the baro-
metric pressure and temperature recorded in Step 12 above.
This is done by substituting each of the flow rates determined
in Step 15 above for Q, in the following equation and solving
for §2-
Q2 -
where
' Q = flow rate determined in Step 15 above
Q_ = corrected flow rate
P. = barometric pressure measured when the hi vol
orifice was calibrated
P_ = barometric pressure recorded in Step 12 above
T, = absolute temperature determined at the time
the hi vol orifice was calibrated, °K
= absolute temperature determined from Step 12, °K.
'2
(Rev. 7/14/81)
-------
__ Page 17
16. Plot the flow recorder readings vs. the air flow rates
17. Use a French curve or a curve fitting technique such
as the least squares fit, to draw a best fit smooth curve
through the calibration points.
18. If any calibration point does not fall within ± 5
percent of the curve, or causes the curve to be S-shaped or
have a sharp turn, rerun that point, recalculate, and replot.
The percent deviation can be calculated by taking the question-
able flow rate (Q ) and the calibration curve flow rate (Q )
for the same flow meter reading.
(Q - Q )
Percent deviation = x 100
should fall within ± 5 percent.
Table 2.1 ACTIVITY MATRIX FOR CALIBRATION OF EQUIPMENT
Equipment
Analytical
balance
talative
humidity
Indicator
Ti»r
Zlapaed tiaa
Mter
Orifice
calibration
unit
Sampler
Acceptance limits
3 to 5 standard weights
covering normal range of
filter weight, all with
indicated weight • true
weight + 0.0005 g
Indicator reading <*
psychrometer reading
± 6*
^15 minutes/24 hours
+2 minutes/2 4 hours
Indicated flow rate -
actual flow rate +_ 4*
!Q0 - Qel
, ° . ' 0 05
we
QQ » observed flow rate
Q^ - flov rate from cali-
bration curve
Frequency and
method of
measurement
Gravimetric test
weighing at purchase
and when performing
periodic calibration
checks
Comparison with
reading of wet-bulb
dry-bulb psychro-
»«ter on receipt
and at 6 -month
intervals
Check at purchase
and quarterly
against elapsed time
meter
Standard timepiece
(known accuracy) at
receipt and at 6-
nonth intervals
Flow rate primary
standard at receipt
and 1-year interval
Calibration orifice
unit, on receipt and
after major mainten-
ance on sampler
Action if
requirements
not met
Have balance main-
tained and calibra-
ted by manufac-
turer's representa-
tive
Adjust or replace
to attain accept-
ance limits
Adjust and repeat
test
Adjust or replace
time indicator to
attain acceptance
limits
1) Adopt new cali-
bration curve if
evidence of orifice
damage is absent
2) Replace orifice
unit if evidence
of da^cage is
present
Rerun points for
which
|Q0 - Qcl
. ,r > n 01
Qc "
until acceptance
Limit attained
(Rev. 7/14/81)
-------
-------
STANDARD OPEEATING PROCEDURE
HIGH VOLUME .TSP FILTER HANDLING AND STORAGE
1. General Discussion
Filters used for High Volume TSP particulate collection are 8" x 10" Sierra
glass fiber filters.
Sample ID codes have a two letter prefix, EH for High Volume TSP filters.
A three digit-number follows the prefix, starting with 001.
All filter handling procedures are to be done in a clean area. Clean the
work area with a methanol dampened Kaydry towel, then lay out a clean Kaydry
to use as a work surface before all handling procedures.
Filters are stored in individual file folders, which, in turn, are placed
inside manila envelopes.
2. Materials and Equipment
• Sierra Model C-305-GF glass fiber filters
• file folders
• manila envelopes
• Kaydry towels
• methanol
• 4-digit number stamp
• Vinyl medical gloves
3. Filter Coding
1. Cut file folders such that they will fit inside 9" x 12" manila envelopes.
2. Place vinyl medical gloves on hands and clean with methanol dampened Kaydry
towel.
3. Select filter to be coded and inspect both sides for foreign particles,
pin holes, discolorations, or other imperfections. Some particles may be
blown off. Discard the filter if defective; otherwise, open cut file
folder and place filter inside.
4. Select ID # to be printed on filter using 4-digit number stamp. Stamp
ID // on upper right hand corner of top face of filter such that ink will
not interfere with sampling area.
5. Close file folder and stamp on upper right hand corner. Stamp manila
envelope with same ID // and place file folder with filter inside.
-------
6. Repeat steps 1 - 5 as necessary.
7. Record ID # and lot number of all filters coded in the RDDP sample
log book.
8. Place loaded filters in sample storage cabinet.
-------
STANDARD OPERATING PROCEDURE
MAINTENANCE FOR SIERRA DICHOTOMOUS SAMPLERS
1. Maintenance Schedule
Maintenance will be performed on a monthly basis.
2. Cleaning the Sampling Module
1. Particulate Deposits
The Sampling Module is disassembled as shown in Figure 1. All parts
are sealed with "0" rings. Particulate internal loss deposits accumu-
late primarily on the outer and inner surfaces of the tip of the receiv-
ing tube in the virtual impactor head. (Figure 2) The remaining internal
surfaces may have slight particulate deposits. These deposits should be
cleaned with alcohol or water using a. camel's hair "brush.
2. Bug Screen
The bug screen is exposed for cleaning by disassembling the aerosol inlet.
Brush all loose material off the bug screen and out of the aerosol inlet.
3. "0" Rings
The "0" rings in the aerosol inlet and the flow splitting chambers should
be conditioned with a light coating of vacuum grease.
3. Battery Beplaceinent
If AC power has not failed during operation, the dry cell battery for
stand-by power need be replaced only every 2-3 years. If AC power
has failed during operation, as indicated by the dot light on the Timer
Module, the battery must be replaced at the next regularly scheduled
maintenance.
To replace the battery, unplug the line power cord, and remove the
front panel of the Control Module by removing the six screws. The bat-
tery is located in a bracket on the lower left hand side of the back
-------
Standard Operating Procedure Page 2
Maintenance for Sierra Dichotomous Samplers
vail of the enclosure.
Leak Testing
The Control Module is leak-checked by installing needle valves on the
coarse-and fine-particle "bulkhead fittings on the side of the enclosure.
Close the valves and turn on the pump. Pressures P, and P. on the vacuum
gages should be -2k to -25 in. Hg-if leaks are negligible. Then gently
close the flov selector valve for the total flow and quickly shut off the
pump. Important Note: .If the pump is allowed to run with the total flow
selector valve shut, the pump will act as a compressor and can cause leaks.
If leaks are negligible, these pressures will increase to about -12 to -15
in. Hg in approximately -20-30 seconds and then will increase to zero in
about 2 minutes. The initial increase to -12 to -15 in- Hg is not caused
by external leaks but rather by a small flow through the pnuematic feed-
back line from the compressor to the vacuum side of the system.
If leaks exist, they most probably are in the filter jars, which should be
tightened firmly. The next leak possibility is the tubing fittings or a
tube improperly in contact with the hot pump and has melted through. Most
leaks can be quickly isolated by use of the inlet valves and the two vacuum
gauges.
-------
FROM AEROSOL INLET
FINS PARTICLES,
LESS THAN 2.5 MICRONS
.OARSE PARTICLES,
GREATER THAN 2.5 MICRONS
ASSETTE
FINE
PARTICLE
FILTER
INLET TUB
0 . 9., CMH
0.1 CMH
VIRTUAL
IMPACTOR
•NOZZLE
•VIRTUAL
IMPACTOR'
RECEIVER T
FILTER-
CASSETTE
COARSE
PARTICLE
FILTER,
37mm Dia.
FILTER
HOLDER
""Jr ~ -CC5. .TO CONTROL MCOULZ
-------
M
o
-------
Page 1
HI VOLUME - GLASS FIBER FILTER WEIGHING USING THE
TORBAL EA-1 AP ANALYTICAL BALANCE
Standard Operating Procedure
1. General Discussion
1. Analytical Problem:
The mass of air particulates collected on glass fiber filters
must be determined to an accuracy of better than ± 10% relative.
Minimum net weight is expected to be about 25 rag.
2. Interferences:
Humidity changes may affect the weight of the filter and of the
deposit. Filters are equilibrated before and after sampling inside
a Constant Humidity Chamber (CHC) 24 hours prior to weighing.
3. Readability: 0.1 mg.
4. Precision and Accuracy:
The balance is calibrated with class S weight. Precision expressed
as standard deviation is 0.2 mg.
5. The technician should read the Torbal EA-l-AP Instruction Manual
entirely before using the balance, paying close attention to
section 3, "weighing procedure". The balance is always left ON to
provide maximum stability.
6. Every tenth filter is a control filter and is labelled accordingly.
7. Keep the calibration weight clean and store in its proper container.
Handle the calibration weight with the cleaned weight forceps only
(non-serrated stainless steel) and do not use the weight forceps
for any other job.
(Rev. 6/11/81)
-------
Standard Operating Procedure Page 2
2. Equipment and Materials
• Torbal EA-1 AP Analytical balance with easel
• Constant Humidity Chamber
• Calibration weight, Class S
• Calibration weight forceps
• Kaydry towels
• Kimwipes
• Vinyl medical gloves
• Methanol
3. Operating Procedure
3.1 Start Up:
L. Remove filters to be weighed from their manila envelopes. Place
file folder with filter inside into the constant humidity chamber.
Allow 24 hours to equilibrate before weighing.
2. Remove hi-vol filter easel from weighing chamber. Fiance vinyl
medical gloves on both hands. With methanol dampened Kaydry
towel, clean: weighing chamber, easel, tare weight, balance
corttrol knobs/ left front corner of CHC and hands.
3. Replace easel to weighing chamber. Clean area around balance and
lay out a clean Kaydry towel on table. Clean forceps using a
methanol dampened Kimwipe.
4. Record technician, date, CHC humidity, room humidity and filter
ID's on "hi volume weigh sheet". Record whether the filters to
be weighed are unexposed or exposed samples.
5. Set weight control knobs and counter control knob to zero. Use the
coarse tare control and zero adjust knob to bring null indicator to
center.
6. Open door and place the calibration weight on easel. Close door and
adjust weight control knobs such that null indicator reads zero.
Record the total weight in the "calib" boxes provided by the data
sheet. Open door and remove calibration weight from easel to
appropriate container.
7. Adjust weight control knobs to zero. Null indicator should read zero;
if not, repeat steps 5-7. When null indicator complies with this
stipulation, check the box to the right of the first filters ID //.
(Rev. 6/11/81)
-------
Standard Operating Procedure Page 3
3.2 Weighing Filters:
1. Remove the first filter to be Weighed from the CHC and.check to
make sure that its ID // corresponds to the ID if on the data
• sheet. Place filter on easel inside weighing chamber and weigh
within 30 seconds. Record weight and note any defects (torn,
•particles falling off, etc.) on the data sheet. Remove filter
from easel and replace inside CHC.
2. Remove another filter, following the same procedure as
described above.
3. After every other filter, the balance must be zeroed. Note any
large deviations from the null zero in comments column.
4. Repeat steps 1-3 until weighing of the set is complete.
5. Place calibration weight on easel and record the calibration
weight.
6. Place calibration and tare weight in their proper containers.
3.3 Reweights:
1. Select at random three filters to be reweighed, preferably by
another technician.
2. Use the same start-up and filter weighing procedures with one
difference, filters from up to four sets can be reweighed at the
same time.
3.4 Calculations:
W ' » (W - W - AC) x 1000
n g t
Where: W = net deposit in mg
n
W = gross weight in g
&
W = tare weight in g
n
£
i . (Gross weight Control. - Tare weight Control.
AL> — "~~" ^^——^—^^-^——^^———^^———*—^^——-^
n
Where: n = the number of control filters in weigh set.
1. Record W in the comments column of the appropriate field data sheet.
n
(Rev. 6/11/81)
-------
Standard Operating Procedure Page 4
3.5 Quality Control:
1. The calibration weight check at the end of a weighing set must
be within ± . 0002 g of their correct values or the entire set
must be reweighed.
2. The reweight must all be within ± .0010 g or the entire set must
be reweighed.
-------
Page 1
Standard Operating Procedure
EPA High Volume TSP Sampler Audit"
fl.O' -"'"AUDITING; PROCEDURE "•" - ',' ."> -\t
'
. . .
~- 'Audit, as used- here, implies an independent: 'assessment of
- the" quality of data obtained by the . ambient'-.air monitoring
. .r-^ methods . Independence .can-, be achieved by .having the -audit made
by" "a .•different operator/ analyst tHan the one conducting the
> . w' '' • •«'*•• •
,.f fouti-Bfe field -measurements, -Th,e audit should- be-, a true assess-
-;.•.„ ' .'' " " ' •-.'": A*. " '
', . . ment oif" the,- i&eassurfiment- process under normal ..operation, i.e.,
., .withdht v,any special preparation or adjus-tmenf of^th'e sys^tem.
Routine- quality assurance checks -conducted .by the operator/
analyst- are necess'ary for obtaining and reporting good quality
data, "but 'they are-'not to be considered as part 'of the auditing
procedure-. .-.>•• :- .. " • ,-. 'j"7 . ;
'Two types of audits' are recommended herein, performance
and system audits. '.V Four1; performance audits and, a systems ".
audi£: are 'described.-.-in detail "in the'-'follQ'wing-"sections~. .An\
.•"•-.,' , . •,..-,-. . • '0 ' -. ' '" ''.;>•'• •' -'V
• '..alternative to p'erfonning four 'individual '-''audits' .'is -t6 '.audit
- * • , ,*•-." "*%" *
- the entire me-asurement process by comparing the final results^.
from the field sampler -to those obtained -with a collocated "..-.
% v . " * ' * ' *•..
: sampler". This alternative is described, in Section- U. 2 .v^.'.-A \ • v . ..
' summary 'of these audits is -'given in Table^ 8*2
-------
Page 2
by the total measurement system (sample collection, sample
analysis, and data processing). Performance audits are normally
a quantitative appraisal of quality.
Four performance audits of individual variables are
recommended:
1. Audit of clean filter weighing.
2. Audit of flow rate calibration.
3. Audit of exposed filter weighing.
4. Audit of data processing.
An auditing level of 7 out of 100 sampling periods is
suggested here as a starting frequency. For the case where.one
sample is collected every sixth day, an auditing level of one
per month is recommended. This would result in an auditing
level of approximately 3 for a lot size of 15 for data reported
quarterly. If the number of sampling periods is greater than
15 but less than 50, four (4) audits are recommended. These
frequencies are suggested starting frequencies and they are
to be altered based on experience and data quality. The audit
frequency should be reduced if past experience indicates the
data are of good quality, or increased if data are of poor
quality. In determining the number of audits to be made for
a large lot size, it is more important to make sure that the
sample is representative of the various conditions that may
influence data quality than to adhere to a fixed frequency.
The supervisor/quality assurance coordinator will specify
the audits and auditing level to be used according to monitoring
requirements.
8.1.1 Clean Filter Weighing Audits - Weighing audits are made
as soon as practical before or after the regular weighing.
Clean filters are normally weighed in batches. This allows
for the sampling to be performed and corrections to be made
before the filters are used.
1. Divide into lot sizes of 100 or less and weigh.
.. 2. Randomly select and reweigh 7 filters .from each lot
of 100. See Appendix I of Volume I of this Handbook for
(Rev. 7/14/81)
-------
Page 3
recommending sampling procedures.
3. If any one of the 7 check weights differs more than
2.8 mg from the original weight, reweigh all the filters in
that lot. Record results in a laboratory log book.
8.1.2 Flow Rate Calibration Audits - Independent flow rate
calibration audits should be made on site. Portable audit
equipment is used.a Perform the flow rate calibration audits
according to the following procedure:
1. Set up equipment.
2. Select one of the resistance plates and obtain the
actual flow rate, Q , and the rotameter reading, following the
a
calibration procedures, Section 2.6.
3. Convert rotameter reading to flow rate, 0 , using
the calibration curve and making corrections for ambient
temperature and pressure.
4. Compute the percent accuracy
Q_ - Q
% A = -2- - x 100. Equation 8-1
^a
5. If the percent accuracy is greater than ± 7 percent
for any one check, a complete recalibration should be performed
before sampling is resumed.•
6. Report 0 , Q , and the percent accuracy, % A, on
an X and R chart, under measurement result, items 1 and 2.
Record .% A in the cells preceded by "Range, R" as indicated
in Figure 8.1. The value, % A, can be positive or negative
and the range is always positive. The sign of the difference
should be retained to determine the existence of trends and/or
consistent biases. The steps involved in the construction
of a quality control chart and in the interpretation of the
results are described in Appendix H, Volume I of this Handbook. '
aUS EPA uses a reference flow device (called an ReF device) whic:
is an orifice (with 5 different orifice plates) that mount
onto the faceplate of the hi vol adaptor. An ReF device
may be purchased from Dexco Co., Inc., 630 Chapel Hill Blvd.,
Burlington, NC 27215.
(Rev. 7/14/81)
-------
^•("si"1.)""
S,
Page 4
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(Rev. 7/14/81)
-------
Page 5
7. Repeat the above for each flow rate calibration audit
plotting all points on the chart and connecting the points by
a straight line.
8. Tentative warning and control lines are given as + 4.7
percent (warning lines) and +_ 7 percent ("out of control" lines).
After 15 to 20 points are plotted, new control and warning lines
may be derived as described in Appendix H of Volume I of this
4
Handbook.
9. Out of control points are an indication of calibration
errors, instrument damage, etc. Recalibrate the sampler prior
to further sampling when out of control.
10. Forward the X and R chart to the supervisor for review.
8.1.3 Exposed Filter Weighing Audits - In order to allow for
possible data corrections, it is necessary to weigh exposed
filters immediately after a 24-hour conditioning period. Thus,
it may be impossible to have lot sizes greater than 10 or 20.
1. Randomly select and reweigh 4 out of every lot size
of 50 or less (this would mean 100 percent checking if 4 or
less exposed filters are weighed at one time). For lot sizes
of 50 or greater, reweigh 7 from each lot.
i
2. Reweigh all filters in a lot if any audit weight differs
by more than +5.0 mg from the original weight.
3. Accept the lot with no change if all audi-ts are within
+_ 5.0 mg of the originals.
4. Record the original and audit weights on an X and R
chart as illustrated in Figure 8.2. Follow the procedure outlined
in steps 6 through 1C in Section 8.1.2. The accuracy A, in this
case would be defined as
A = Original Weight - Audit Weight (mg). Equation 8-2
Tentative warning and control limits of + 3.3 mg a"nd + 5.0 mg,
respectively, are recommended until sufficient data are obtained
(Rev. 7/14/81)
-------
Page 5
Table 7.1 ACTIVITY MATRIX FOR MAINTENANCE
XqoipaMt
Sopler Motor
faceplate gasket
kotaaeter
•star Baskets
Sampling head
Acceptance limits
-400 hours operation of
setor brushes
-Absence of malfunction
Absence- of leeks *c filter
•••1 -
-Ab'cnea of foreign at*teri*la
-Subl* op«r»cion»
LaaJe t±7ht fie
Xb*«nea of leaks
frequency andl
method of
a«««ur«m«nt
Vi«u«lly check upon
r«c«ipt *nd after each
400 hours of operation
Visually check after
•ach sampling period
Visually check for each
sample
Visually check each 400
hours of operation
Visually check each 200
hours of operation
Action i.:
requirements
not met
-Replace motor
brushes
-Other staintenJ
as indicated
Replace Basket
Clean: replace
if damaged
Replace gaskets
Replace 5aipljj
head
Rev. 7/14/81)
-------
X anu K CIIAiti
PROJECT I
NAMB I
DATE 74.
6
Cuidil
SUM
AVERAGE
t/l
JII17
J7I0.7
SOW
l/Zi
3NI.O
T11I.5
Jlbtt
sin*
WJil
Lot
4/L
MEASUUEMKNT
UNITS
4/0
Jftftf
3143
JJHM
Iht.7
3:.;
ItTS.'l
1ZT4?
5/I.3 5/ZO
3TKI
37H?
- _\- — oo
(U
Figure 8.2 Quality control chart for audit of weights of exposed filters
-------
Page 7
to support an alteration of these limits. Do not increase the
•limits unless so authorized by the Administrator.
5. Forward the X and R chart to the supervisor for review.
6. Out of control points indicate the need for recalibra-
tion of the balance and/or improved operator technique. Reweigh
all of the remaining exposed filters in the lot.
8.1.4 Data Processing Check - In auditing data processing
procedures, it is convenient and allows for correction to be
made immediately if audits are made soon after the original
calculations have been performed. In particular, this allows
for possible retrieval of additional explanatory data from
field personnel when necessary.
1. Use the same audit rate as step 1 of 8.1.3.
2. The check is made starting with the raw data on the
data sheet or flow rate recorder chart and continuing through
the recording of the concentration in yg/m on the SAROAD form.
3. If the mass concentration of suspended particulates
commuted by the audit check, (yg TSP/m ) , differs from the
3
original value, (yg TSP/m ) by as much as + 3 percent, all
samples in that lot are checked and corrected as necessary.
The audit value is always given as the correct value under
the assumption that a discrepancy between the two values is
always double checked by the auditor.
4. Audit values are recorded in the data log and reported,
along with the original values, to the supervisor for review.
8.2 Auditing with a Collocated Sampler
An alternate method of auditing the high volume method,
which in certain situations might be feasible, is to use two
collocated samplers. A network operating several samplers
in a reasonably small area (e.g., city or county) might find
this method more convenient than auditing individual variables.
The field sampler and the audit sampler will be denoted
respectively, as the first and second sampler-throughout
the section.
(Rev. 7/14/81)
-------
Page 8
The second sampler should be operated in strict accordance
with the procedures given in this section of the Handbook. A
record should be maintained of the checks performed on the second
sampler and reported with the data as requested by the manager.
An audit would be to place the second sampler adjacent to
(but no closer than 6 feet) the field sampler (see Reference 1
for discussion on positioning the sampler) and sample simul-
taneously.
The percent difference in the concentration of suspended
particulates as measured by the field sampler and the second
sampler is computed by
(ygTSP/m3) - (ygTSP/m3)_
Percent = %D = . —± =-2-T x 100. Equation 8-3
difference 0. 5 I (ygTSP/m3) 1 + (ygTSP/m^J
Based on the results of a collaborative test a defect would
be defined as
|D | >_ 15.*
The auditing level for collocated samplers would be the
same as that given in the previous section, i.e., n = 7, N = 100
as the initial rate.
Values of (yg TSP/m'),, (yg TSP/m )2/ and D, and the
auditing level would be reported on the quality control
X and R chart along with standard identification information.
The data may be analyzed and reported as described in
steps 6 through 10 of Section 8.1.2,' above, with the exception
that the difference, D, is obtained by equation 8-3. Tentative
warning and control limits are given-as 10.0 and 15.0 percent
respectively. Out of control values may imply errors in any
one of the several sample collection and analysis steps.
Audits of specific steps will aid in determining the likely
*If a = 3.5 percent of the concentration of TSP for each sampler,
then the percent difference, D, would have a standard deviation
of 5.0 percent of the mean value. This gives a 3o value of 15
percent.
(Rev. 7/14/81)
-------
Page 9
cause of the large deviations, e.g. calibration, weighing,
and/or data processing errors. See Figure 8.3 for an example
quality control chart.
8.3 Systems Audit
A systems audit is an on-site inspection and review of ^
the quality assurance system used for the total measurement
system (sample collection, sample analysis, data processing,
etc.). System audits are normally a qualitative appraisal
of system quality.
A systems audit should be conducted at the beginning of
a new monitoring system and as appropriate thereafter to audit
significant changes in system operation.
A preliminary form for use in a system audit is given
in Table 8.1. These questions should be checked for the
applicability to the particular local, state, or Federal agency,
(Rev. 7/14/81)
-------
PROJECT
NAME
™J£!fc
u
SUM
AVERAGE,X
7»D RANGE, n
Lofc
*17
20 —
10 —
a
' 13
-10-
-ZO-
13
U}J <
§K§~
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5S^«
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8
MEASUREMENT .,
UNITS Ibcizntdiffacnde
J52,
31
154
JHS
3J
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u
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n »i 1,1
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Figure 8.3 Quality control chart for audit with collocated samplers
-------
Page 11
Table 8.1 CHECK LIST FOR USE BY AUDITOR
FOR HI VOL METHOD
1. What type of hi vol samplers are utilized in the network?
2. Hov often are the samplers run? (a) daily, (b) once every
six days, (c) once every 12 days, (d) other.
3. What type of filter and number is being utilized?
4. Are there any pre-exposure checks for pin holes or imper-
fections run on the filters?
5. What is the collection efficiency for your filters?
6. What is the calibration procedure for the hi vol sampler?
7. Which statement most closely estimates the frequency of
flow rate calibration? (a) once when purchased, (b) once
when purchased, then after every sampler modification, or
(c) once when purchased, then at regular intervals there-
after.
8. Are flow rates measured before and after sampling period?
9. If the answer to t8 is yea, using the equation below, what
is the estimated average percent of change in the flow
rates? Use the equation
100(Q. - Q.)
-r - percent change
(a) less than 10%, (b) 10-20%, or (c) greater than 20%.
10. Is there a log book at each sampler to record flows and
times?
11. Are filters conditioned' before initial and final weighings?
. If so, how long? . And at what percent
humidity? .
12. Is the balance cheeked on a periodic basis? . If so,
how often? .With which standard weights?
13. How often are the hi-vol filters weighed?
How is the data from these weighings handled?
14. Are all weighings and serials numbers of filters kept in a
log book at the laboratory?
15. What is the approximate time delay between sample collection
and final weighing? ' ' days
(Rev. 7/14/81)
-------
Page 12
Table 8.2 ACTIVITY MATRIX FOR AUDITING PROCEDURE
Audit
Weighing audits
Clean filters
Exposed filters
Calibration audit
Data processing
audit
Collocated sampler
audit
(ystvm*
audit
Acceptance limit*
Audit vt. - original wt. * 2.8 wj
Audit vt. " original vt. * 5.0 ag
flow rate
°'" ^ rlov rat.a i X-07
Flow rat«a • routine »««»ur«d r*t%
flow rrnte^ - Audited rate
iuc TSP/m^
(ug TSP/m-i)a
(ug TSP/»^) • routine neasured con-
centration
(119 TSP/n*) • audited conc«ntration
100[(u9 TSf/a^)i - (»q TSP/«J)j] -
Av*ra?« lug TSP/» ) ^ and 2
i.«., th« difference in concentration
do«> not exceed 15% of the average value
obtained by the field saapler 1 and the
collocated sampler 2.
These liaits are for repeatability (cane
operator) . Larger limits would be ex-
pected for reproducibility (between
two operators ) .
Method •• described 'In
this *«ctioa of ui«
Handbook.
Frequency and
awthod of
measurement
Freguancv - 7 audits
per 100 filters. For
a lot size of SO or
less filters aaJce 4
audits .
Method - Ose analytical
balance . Condition
filters for 24 hours
before weighing
rreourncy - See above.
Method" — Sane as for
calibration procedure
for one flow rate.
Frecruenc-y - See above.
Method - Re4o all cal-
culations > readings of
charts, etc. through
recording results.
Preouenc^ - S*« above.
Bonitor calibrated and
naintained in strict
accordance to method
description.
yrgguTncv - At the
b*vliULiaf of »_ new
•onitorinf cystesi
and periodically as
appropriate
I*-"""! "S-~.i£*en of
r-^*--*vr>Dts
not "Mt ;
Reveigtt all filters
in the batch
Perform calibra-
tion before
sampling is
resuned.
Recheck all calcnt-
lationa.
Data invalid for
Initiate iav10*"*1
•ethods aad/or train-la,
pctxjruu
(Rev. 7/14/81)
-------
Dichotomous Filter Handling and Data Procedures
I. General Discussion
Dichotomous filters best suited for the CMB analysis of ambient
particulate material consist of a polyolefin supporting ring bonded
to the top (particle collection) surface of a teflon membrane. The
filters are 37 -mm in diameter.
Sample ID codes should consist of a letter prefix indicating the sample
site and whether the filter is the fine or coarse fraction. Sequential
three digit numbers should then be used for the sample number, e.g.,
BFSC 012 and BFSF 012 might represent the twelfth sample (both coarse
and fine) collected in Bakersfield (B) at the fire station (FS) site.
The most important point to emphasize is that both the coarse and fine
fraction filters should have the same numerical code to facilitate data
interpretation and the letter portion should reflect the sample site
and whether it is the coarse or fine fraction (C or F).
Maintain a sample log book. Record sample sites, filter numbers, dates,
comments, volumes* weights and filter lot numbers.
All filter handling procedures should be done in a clean area. Clean
the work area with a methanol dampened Kaydry towel, then lay out a
clean Kaydry towel to use as a work surface before all handling procedures.
The filters must be handled only by the supporting ring with clean forceps.
A laminar flow clean hood is the most appropriate work area. Disposable
elastic gloves should be worn when working with filters.
Petri dishes, slides and cassettes can be reused but must be
wiped clean with methanol before reuse.
II. Materials and Equipment
Sierra Model FH-240-P filter cassettes
• Millipore plastic Petri dishes (PD 10 047 00)
• Millipore plastic Petri slides (PD 15 047 00)
• Ghia Corp. 2y PTFE 37 mm filters with polyolefin rings
(R2P503700)
• field sample transport boxes
shipping boxes
forceps
• Kaydry towels (VWR Cat. // 21903-008)
methanol (polyethylene wash bottle)
waterproof fine point marker (e.g. Pilot Corp. extra fine
point permanent markers)
-------
adhesive labels
disposable plastic gloves (e.g., Tru-Touch Vinyl Medical
Gloves, VWR cat tf 32901-060)
Tip-n-Tell shipping indicators
III. Laboratory and Field Procedures
1. Lay out a series of 6 - 10 Petri dishes on the work surface,
label with the sample ID numbers, recalling that there
should be coarse and fine pairs.
2. Select a new filter and inspect both sides for foreign
particles, pin holes, discolorations, or other
imperfections. Some particles may be carefully blown off.
Discard the filter if defective.
3. Steady the filter by pressing down on the plastic ring of
the filter with forceps. Write the ID number as recorded
on the Petri dish on the plastic ring of the filter using
a fine point waterproof marker.
4. Weigh the numbered filter and record in log book. Also
record the filter lot number.
5. Place the bottom half (female part) of a clean Sierra
filter cassette on the work surface and place the weighed
and numbered filter into it. The filter should be placed
top (numbered) side up. Place the top half (male part)
of the clean Sierra filter cassette in position over the
bottom half and press down so that it snaps into proper
alignment.
6. Label the edge of the cassette with an adhesive label.
The number should correspond to the number on the Petri
dish and polyolefin ring.
7. Place the loaded cassettes into the corresponding Petri
dishes.
8. Place the Petri dishes into the field transport box (in
coarse-fine sets).
9. ' Once at the sampling site, place the cassettes into the
dichotomous samplers (bevelled side down) again making sure
that each coarse-fine set is placed into one dichotomous
sampler. Retain the numbered Petri dishes in the field
transport box.
-------
10. Record the. sample site, sampler serial number, filter ID
number, start and stop flow rate, start and stop time and
volume, as well as the initials of the operator and
comments onto data sheets (sample attached). Note: Total (T)
flow rate and volume and coarse (c) flow rate and volume are
measured and recorded.
11. After a 24 hour sample has been collected, the loaded filter
cassette should be placed into its corresponding numbered
Petri dish and.returned to the laboratory.
12. Label clean Petri dish slides with the sample ID numbers.
13. Select a Petri dish containing an exposed filter from the
sample transport box and place on the work surface. Obtain
the Petri slide with the matching ID and place on the work
surface.
14. Remove the Petri dish lid and, being careful not to touch the
filter, remove the filter cassette assembly from the Petri
dish. Remove the side label and carefully separate the
cassette assembly. Then using a pair of forceps, transfer the
filter to its Petri slide.
15. Record any unusual appearance or condition of the filter in the
sample log book.
16. Weigh the loaded filter and record the weight in the sample log
book. Replace the filter into its numbered Petri slide. Pinch
the edge of the filter in the Petri slide when closing the slide
to hold the filter in- place. Note: Less than 100 Petri slides
per tray can be held when they are loaded due to the increased
thickness caused by pinching the filter.
17. Place the Petri slides into the plastic trays. Put the
cardboard boxes containing the trays into a cabinet or other
protected location until enough are collected for shipment.
IV . Shipment
1. Place the cardboard boxes containing the plastic trays of
loaded Petri slides into the flanged shipping box in such a
manner so that all filters are held upright during shipment.
Include filters from each filter lot number for blanks.
2. Photocopy the data sheets and appropriate pages from the
sample log book for enclosure into the shipping box. Include
the uncorrected mass of particulate material collected on the
filters in micrograms.
3. Place a "Tip-n-Tell" indicator on the shipping box with the
accompanying label. Activate the "Tip-n-Tell" indicator.
4. Ship directly to NEA Laboratories, Inc., 8310 S.W. Nimbus Avenue,
Beaverton, Oregon, 97005.
-------
LOW-VULUML inCIIOTUMOUS KllilJ) DATA Slltbl1
OX LC
Serial^
ID//
F
C
f
^
F
C
Sampled
Start
T
c
Stop
Start
•
T
c.
F
C
T
C-
Stop
Net
F
t
f
r
f
y
F
C
•
/
F
C
'•
T
c
T
C
-i- — , — . ., i _ - - .
i-IIJ-l. J.U1.D
T
C
T
c
T
c
T
c
T
c
•
T
C
i
I
-------
Soil and Road Dust Sample Sieving
11.1 General Discussion
The bulk soil and road dust samples collected according to SOP #12 and #13
must be segregated before analysis. This procedure describes the isolation
of two size fractions, <75 ym and <38 urn.
Special care must be taken to prevent the spread of dust to any other sample
handling or analysis area of the lab, and to prevent cross-contamination of •
the soil samples. Clean' the work area and spatulas with methanol dampened
Kaydry towels between each sample handling.
11.2 Materials and Equipment
1. Set of Tyler sieves, as indicated USA No. Opening
um
plus top cover and bottom pan.
18 1000
40 425
80 180
200 75
400 38
2. Tyler sieve shaker, Model RX-24
3. Polyvials, 26 ml.
4. Kaydry disposable towels.
5. Compressed air.
6. Spatulas, large and small sizes.
7. Methanol.
8. Soft bristle brush.
-------
Standard Operating Procedure
Page 2
11.3 Flow Diagram
Remove bulk
sample from storage
Transfer to 18, 40, 80
and 200 mesh sieve
assembly
Shake one hour
Clean 18, 40, 80,
and 200 mesh sieves
Place an aliquot
of the <75 urn
fraction in labeled
vial
Place rest of the <75
ym fraction in 400 mesh
sieve assembly
Return the >75 ym
fraction to sample
storage bag
Shake one hour
Clean'400 mesh sieve
Place the <38 ym
fraction in labeled
vial(s)
Return the <38 ym
fraction to sample
storage bag
I
Place sample
vials in storage
Return remaining bulk)
sample to storage
-------
Standard Operating Procedure Page 3
11.4 Sieve Cleaning
1. This procedure should be done in a room dedicated for sieve cleaning
or outside to prevent the spread of dust to sample handling areas of
the lab.
2. Use compressed air to blow away all loose dust. Pay particular attention
to the screen, the screen-to-frame joint, and overlapping surfaces on the
frame.
t
3. Carefully brush all loose dust from the wire mesh screen with a soft
bristled brush.
4. Wipe all loose dirt from the frame with a. brush or Kaydry towel. Clean
both inside and outside and below as well as above the screen.
5. Repeat steps 2-4 until the sieve is clean.
11.5 Sieving
1. Clean the bottom pan using a methanol dampened Kaydry towel and assemble
the cleaned Tyler sieves in the following order, from the bottom to top:
bottom pan, 200 mesh screen, 80 mesh screen, 40 mesh screen, 18 tnesh
screen.
2. Select a sample from the sample storage cabinet for processing.
3. Remove the inner bag and sample data card from the outer bag. Set them
aside for later use.
4. Transfer the contents of the sample bag to the sieve assembly; minimize
the loss of fine dust by dumping the sample into the sieve slowly and
carefully. Set the sample bag aside for later use.
5. Clean the top cover using a methanol dampened Kaydry towel and compressed
air, and put the top cover into position on the sieve assembly.
6. Place the sieve assembly into position on the shaker. Press Che locking
tab down firmly onto the sieve assembly with one hand and tighten the
locking tab screw with the other hand. Repeat for the other locking tab.
7. Start Che shaker. If dust escapes from the sieve assembly, either the
assembly is not mounted tightly enough, or there is foreign material be-
tween the mating surfaces of the sieves. Correct and restart if neces-
sary. Using the built-in timer, run the shaker for one hour.
8. While the sample is shaking, clean the sieve(s) not in use according to
the procedure in section 11.4.
-------
Standard Operating Procedure Page *
9. Remove the sieve assembly from the shaker and set on a clean Kaydry
towel. Remove the sieves and top cover as a unit from the bottom pan
and set on a clean Kaydry towel.
10. Using a clean spatula, transfer dust from the bottom pan to a new 26 ml
Polyvial. Fill the Polyvial about half full. Close the lid and cut off
the hinge. Recore "I.D. ^ (from the sample data card) and "size
<75 urn" on an adhesive label. Stick the label on the Polyvial and secure
in place with a piece of transparent tape.
11. Place the clean 400 mesh sieve on a clean Kaydry towel. Carefully pour
the sample remaining in the bottom pan into the 400 mesh sieve; tapping
lightly on the pan will remove most of the material.
12. Transfer the material remaining in the 18, 40, 80 and 200 mesh sieves
carefully into the bottom pan; tapping lightly on the sieve frame will
remove most of the material.
13. Transfer the material from the bottom pan to the sample bag.
14. Use a methanol dampened Kaydry towel to clean the bottom pan.
15. Place the 400 mesh sieve on the bottom pan and the top cover over the
400 mesh sieve. ^
16. Repeat steps 6 thru 9.
17. Using a clean spatula, transfer dust from the bottom pan to a new 26 ml
Polyvial. Use more than one Polyvial if necessary. Close the lid and
cut off the hinge. Record "ID f? " (from the sample data card)
and-"Size <38 urn" on an adhesive label. Stick the label on the Polyvial
and secure with a piece of transparent tape. Record "ID if " and
"Vial 1 of 2" or "Vial 3 of 3", etc. on the lids of the Polyvials from
both-size fractions.
18. Transfer material from the 400 mesh -sieve to the bottom pan, and from
the bottom pan to the sample bag. Close the bag and seal with tape.
19. Record the date of sieving and initials on the sample data card. Place
the inner sample bag and data card into the outer bag.
20. Return bulk sample and Polyvials to sample storage cabinet.
-------
TEFLON FILTER WEIGHING USING THE CAHN 27 ELECTROBALANCE
Standard Operating Procedure
1. General Discussion
1. Analytical Problem:
The mass of air particles collected on teflon membrane filters must
be determined to an accuracy of better than ± 10% relative. Two
sizes of filters are used, 37 and 47 mm diameter, with tare weights
of about 75 ± 20 mg and 120 ± 20 mg, respectively. Minimum net
weight is expected to be about 120 yg.
2. Interferences:
Electrostatic charge on the filter is one possible source of inter-
ference. This is eliminated by use of a beta source charge neutralizer.
Humidity changes may affect the weight of deposit, but not the weight
of filters, since they are non-hygroscopic. Humidity changes are
minimized by performing the weighing procedures in an air conditioned
laboratory.
3. Minimum Detectable Quantity: 15 yg (three sigma).
4. Precision and Accuracy:
The balance is calibrated with class M weights. Repeatability
for the immediate reweighing of a filter is ± 1 yg; long term repeat-
ability ±£ ± 5 yg.
5. The technician should read the Cahn 27 Instruction Manual entirely
before using the balance, paying close attention to Section 3, Balance
Operation. The balance is always left ON to provide maximum stability.
6. Keep the calibration weights clean and store in their proper
container. Handle them only with the cleaned weight forceps (non-
serrated stainless steel) and do not use the weight forceps for any
other job.
(Rev. 9/25/81)
-------
2. Equipment and Materials
• Cahn 27 Electrobalance with custom 60 mm open stirrups
• Po210 charge neutralizer
• Calibration weights, 10, 20, 50 and 100 mg Class M
• Tare weights, 20 50 and 100 mg Class C
• weight forceps
• filter forceps
• Kaydry towels
• Kimwipes
• Methanol
3. Operating Procedure
3.1 Start Up;
1. Remove the stirrups from the weighing chamber as in Section 3.1.2
of the Cahn 27 Instruction Manual and set aside on a clean Kimwipe.
Clean the weighing chamber with a methanol dampened Kimwipe.
Replace the stirrups, one on the A side and one on the TARE side.
Place the charge neutralizer in the center of the weighing chamber.
Clean the area around the balance and lay out a clean Kaydry towel
in front of the weighing chamber. Clean the weight forceps (non-
serrated stainless steel) and filter forceps using a methanol
dampened Kimwipe.
2. Obtain the calibration weights and the filters to be weighed
from the sample storage cabinet.
3. Record technician, date and filter lot number on the data sheet.
4. Determine approximate weight of one of the filters by weighing
on the A200 range. Select the 10, 20, 50 and 100 mg calibration
weights in combination such that their combined weight equals
within + 8 and - 12 mg of the filter weight. (When doing gross
weights or reweights, use the same weights as for the tare
weighing).
5. Set the balance controls to RANGE: A 20 and RESPONSE: 0. Make
sure CALIBRATE, COARSE and FINE ZERO controls are locked. Press
TARE twice to untare the balance.
6. Place the selected calibration weights on the A pan and balance
with appropriate tare weights on the TARE pan so that the display
reads 0 • + 20 mg.
(Rev. 9/25/81)
-------
7. When the display stabilizes (after at least 30 seconds), press
TARE to zero the balance.
8. Add the 20 mg calibration weight to the A pan (or remove it if
already there). Display should read + 20.000 ± 0.001
(or - 20.000 ± 0.001) when it stabilizes. If not, adjust CALIBRATE
accordingly.
9. Replace calibration weight and note that 0.000 ± 0.001 is displayed.
If not, repeat steps 7 and 8. Record tare weight as the sum of the
calibration weights ± display reading, and the calibration reading
on the data sheet.
10. Remove calibration weights to their container.'
3.2 Weighing Filters:
1. Up to 25 filters per set can be weighed. When weighing the
filters, note any defects (torn, particles falling off, etc.)
on the data sheet.
2. Place the first filter to be weighed on the charge neutralizer.
After a few seconds, transfer the filter to the A platform and
place the next filter to.be weighed on the charge neutralizer.
3. When the display stabilizes (after at least 30 seconds), record
the filter ID number and weight reading including + or - sign on
the data sheet.
A. Transfer the filter from the A platform to its container, transfer
the filter on the charge neutralizer to the A platform, and place
the next filter in sequence on the charge neutralizer.
5. Repeat steps 3 and 4 until weighing of the sec is complete.
6. Place the calibration weight(s) on the A pan. Record tare weight
as the sum of the calibration weights ± display reading. Press
TARE if the reading is not 0.000.
7. Add the 20 mg calibration weight to the A pan (or remove it if
already there). Record calibration reading.
8. Place calibration and tare weights in their containers.
3.3 Replicates:
1. Select at random three filters to be reweighed, preferably by
another technician.
(Rev. 9/25/81)
-------
2. Weigh che filters using the procedures in sections 3.1 and 3.2.
Indicate that the weighings are replicates on the data sheet.
Filters from up to 8 sets can be reweighed at the same time.
3. Calculate the difference, W , between the original and replicate
weighings.
3.4 Shutdown;
1. Replace the filters that were weighed in the sample storage
cabinet.
2. Clean the balance as in 3.1.1.
3, Record the date of weighing in the appropriate Sample Log Book.
4. Calculate net weights if appropriate.
5. Return the data sheets to the laboratory supervisor.
3.5 Calculations:
W - (W - WJ X 1000,
n g t
where, W = net deposit in yg
•
W = gross weight reading in mg
o
W = tare weight reading in mg
W, = (W - W ) X 1000
d g r
or
Wj » (W - W ) X 1000,
d t r
where, W = difference between original and replicate weights in ug
W = replicate weight reading in mg.
3.6 Quality Control:
1. The tare and calibration weight checks at the end of a weighing set
must be within ± 0.004 mg- of their correct values or the entire
set must be reweighed.
2. Replicate weighing differences, W , must be _< ± 10 ug or <_ 2% of W or
the entire set must be reweighed.
(Rev. 9/25/81)
-------
3.7 Quality Assurance:
1. Class M weights are used for calibration. According to NBS
circular 547, they are "...designed for use as reference standards,
for work of the highest precision, and for investigations demanding
a high degree of constancy over a period of time."
2. 12% replicates ensure that weighing precision is within limits.
3. Calibration and tare operations are performed before each set
of 25 filters and are checked for accuracy after each set.
4. Results of replicate weighings and calibration and tare weight
checks are reviewed by the laboratory supervisor. He must initial
the data sheet before the data is considered valid.
(Rev. 9/25/81)
-------
Page 1
Standard Operating Procedure
EPA High Volume TSP Sampler Calibration
1- Elapsed Time Meter
The elapsed time meter (synchronous motor type 60 hertz)
should be checked on site or in the laboratory every six
months against a timepiece of known accuracy. If the indica-
tor shows any signs of being temperature sensitive, it should
be checked on site during each season of the year.
A gain or loss of more than 2 minutes in a 24-hour period
warrants an adjustment or replacement of the indicator.
Record results of these checks in the calibration log
book.
2. Timer
For those samplers that are equipped with an on-off timer,
the timer should be calibrated and adjusted using a calibrated
elapsed time meter as the reference. An example of this type
calibration procedure is presented below. Figure 2.2 depicts
the wiring diagram for use in this calibration.
The timer calibration procedure should be performed on a
quarterly basis. Calibration data are recorded in the Timer
Calibration Log. See Figure 2.3 for an example. The steos
in the calibration procedure are:
1. Plug a correctly wired timer into an electrical outlet.
2. Set the timer to the correct time.
3. Set the ON and .OFF time trippers for a 24-hour test
period.
4. Plug the test light into one of the output plugs and
an elapsed time meter into the other.
5. Check the system by manually operating the switch ON
and OFF.
(Rev. 7/14/81)
-------
Page 2
6. Allow the system to operate for the 24-hour test
period and determine the elapsed time from the elapsed time
meter.
a. If the elapsed time is 24 hours + 15
minutes, the timer is acceptable for
field use.
b. If the elapsed time is not 24 hours
+ 15 minutes, adjust the tripper
switches and repeat the test.
Indicator lamp
ON-OFF Timer
(± 15 min/24 hours)
Elapsed time meter
(± 2 min/24 hours)
Figure 2.2 Diagram of a timer calibration system
3. Orifice Calibration Unit
The orifice calibration unit should be calibrated against a
secondary standard, for example a Rootsmeter, upon receipt and at
one-year intervals thereafter. The manufacturer's average calibration
curve can be used unless the calibration deviates from it by more
than ± 4 percent at any one point along the curve. When deviations
from the manufacturer's curve are larger than ± 4 percent and
there are no visible signs of damage to the orifice, the cali-
bration should be repeated by another operator. if the large
deviations persist (after the secondary standard has been checked
(Rev. 7/14/81)
-------
114 1
Timor
No.
1321
Oa«-e.
Start
do/75
Stop
Jlllfe
Elapsed ti.-ce
Indlcdtor
serial No.
0 \J() 0 %.0 (f>
Test
period
44hr5.
Elapsed time
indicator reading
A3 hrs. 53 rv),n.
Accuracy
97. 5
By (signature)
£. ty&ru^
/
Figure 2.3 Example of a timer calibration log 21
ID
-------
Page 4
and found satisfactory) a new average calibration curve is
constructed using the results from at least five sets of
calibration data.
Orifice units should be visually inspected for visible
signs of damage to the orifice before each use. A calibra-
tion check should be made if the orifice appears to have any
nicks or dents.
The following stepwise orifice calibration procedure is
adapted from Reference 3.
1. Assemble the parts as shown in Figure 2.4.
2. Zero the water and mercury manometers by sliding
their scales until the zero on the scale is level with the
meniscus as illustrated in Figure 2.5.
3. Check the level of the positive displacement meter
table. Adjust the legs if necessary.
4. Install Load Plate 18 between the orifice and the
positive displacement meter.
5. Turn Hi Vol motor ON, and let the system operate 5
minutes. While the unit equilibrates, continue with steps
6-9 below.
6. Write Plate #18 under the Plate # Column in the Hi
Vol Orifice Calibration Log. See Figure 2.6 for an example.
7. Record the date, time, orifice number, name of
primary standard (positive displacement meter) and the
serial number of the primary standard in the appropriate
spaces in the log.
8. Record the temperature in °C.
(Rev. 7/14/81)
-------
Page 5
MEROJR'
MANOMETER
THERMOMETER
BAROMETER
POSTIYE
DISPLACEMENT
METER
IAL I 5
UNCOMPENSATED
HI-VOL
MOTOR
* «f nositive displacement
Figure 2.4 Diagram of positive
(Rev. 7/14/81)
meter system
-------
00
H
c
-3-
-2-
-1-
3
H
J
vc _ — p/
MERCURY
MANOMETER
ZEROED
K^i
:::!:::
-2-
-1-
-1-
-2-
^J
^
^^***iMU>"*^^
WATER
MANOMETER
ZEROED
70mm
y
'ME
MAf^
RE
P =
- 4-
-3-
- 2-
-1 -
- 1-
_ o
t
-4-
±~A
RCUR\
OMETE
AD INC
70nn
=7
r
:R
k
>
w
MA
R
P,
-3-
-2-
i _
-1-
-2-
WATER
NOMET
EADIN
- 3.0
i /
ER
G
In.
j ,
Pt =
W
UQ
(T)
Figure 2.5 How to read mercury and water manometers
-------
Description
Derivation
^X^ymbol
Plate^v.
Number ^"X^
&
~T
13
1^
18
Ft.3 of
Air
\
100
100
100
100
100
100
100
100
100
100
3
m of
Air
\
2.83
2.83.
2.83
2.83
2.83
2.83
2.83
2.83
2.83
2.83
Barometric
Pressure
mm Hg
Pa
7^7
1(0-1
767
7k7
767
Vacuum
in Standard
in nun Hg
Pm
7o
TO
TO
70
7£>
Absolute
volui.w in m
v (Pa"Pra)
•V- Pa
V
2.57
Z.S7
2.B7
2L57
•2.S-7
Time in
Minutes
t
7.73
1.64
(.43
i.zq
I.2Z
Flow rate
ra-Vniin
V
a
t
'I
o.Q^
1.4-
I.B
z,o
2.1
Pressure Drop
Across the
Orifice in
inches of water
Pt
2.5
6.S
II. O
IS.5
18.3
00
Orifice Number
Temperature ZiS.Q
Date (C\-~A
Manufacturer
C Barometric Pressure
Primary Standard
Calibration voltage
Verified By
Time JQ.-45 d.m
Serial Number (Q42.3
OQ
(B
Figure 2.6 Example of hi vol orifice calibration log
-------
Page 8
Definitions "for use with Figure 2. 6
V = Actual volume of air measured in cubic meters.
a
V = Volume measured by the positive displacement meter in
c cubic feet
V = Volume measured by the positive displacement meter in
m cubic meters as calculated from Vc.
P = Atmospheric pressure in mm Hg.
3.
P = Vacuum at the inlet of the positive displacement meter
m in mm Hg.
t -= Minutes of time elapsed during run.
Q1 = Flow rate in cubic meters per minute'at prevailing
atmospheric pressure and temperature (uncorrected).
P . = Pressure drop across the orifice in inches of water.
Equations given in Figure 2.6
V • = V x 0.0283
m c
-------
Page 9
9. Record the barometric, pressure in mm Hg.
10. After the 5-minute equilibration period, read the
mercury manometer and record this value in column P . The
example given in Figure 2.5 shows a reading of 70 millimeters
(mm) .
11. Read the water manometer and record this in column
P . The example given in Figure 2.5 shows a reading of 3.0
inches.
12. Wind the stopwatch and set it in the horizontal
position with the dial facing up.
13. Locate the uncompensated dial on the left end of the
positive displacement meter. The location is shown in Figure
2.4. Note: this dial must be viewed from the end. One
revolution of Dial #5 equals 10 cubic feet of air passed through
the positive displacement meter.
14. Use a stopwatch to measure the time in minutes and
hundredths of minutes for exactly 10 revolutions of Dial #5
(i.e., for 100 ft of air to pass through the positive dis-
placement meter). Record 100 under column V and the elapsed
time under column t.
15. Record 2.83 under column V to convert cubic feet to
- - — m
cubic meters.
•
V = V x o.0283
me ^
•3 m _ _ _ _ 3
100 ft3 x 0.0283 ~3- 2'83 m
16. Turn the motor OFF.
17. Repeat this procedure with each of the other load
plates in the set.
18. Repeat Steps 1-17 one time.
19. Calculate and record V for each run.
a.
(3?* ~ PJ
V = v a m_
am p
a
20. Calculate and record Q, for each run.
-------