Toxics in Schools, VOC SOP
Rev. No. 2
July 21,2009
STANDARD OPERATING PROCEDURE
FOR
MEASUREMENT OF VOLATILE ORGANIC
COMPOUNDS USING CANISTERS WITH PASSIVE
AIR SAMPLING KITS
U.S. Environmental Protection Agency
Region 4, Science and Ecosystem Support Division
Athens, Georgia, 30605
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Toxics in Schools, VOC SOP
Rev. No. 2
July 21,2009
Acknowledgement
This Standard Operating Procedure (SOP) was developed by EPA Region 4,
Science and Ecosystem Support Division. This SOP is based on the
Commonwealth of Kentucky's ambient monitoring SOP template. Special thanks
to the State of South Carolina and ERG for operational content.
For questions or comments please contact:
Tim Slagle, EPA, Region 4, SESD at slagle.tim(S)epa.gov or 706-355-8741
Greg Noah, EPA, Region 4, SESD at noah.greg@epa.gov or 706-355-8635
Mike Jones, EPA-OAQPS-AQAD at iones.michael(S)epa.gov or 919-541-0528
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Toxics in Schools, VOC SOP
Rev. No. 2
July 21,2009
Table of Contents
I. Introduction 4
II. Installation 6
A. Sampler Siting 6
B. Sampler Installation 6
III. Operating Procedure 7
A. Equipment and Supplies 7
B. Sampler and Sample Media Receipt Activities 7
Sampling Apparatus 7
Nutech 2701 Programmable Field Canister Timer 7
Sample Collection Canister 8
C. Conducting the Sampling Event 8
Site Arrival Daily Activities 8
Sample Recovery and Data Collection 9
Preparing Sampling System fora Sampling Event 10
Sample Shipping 11
IV. Quality Assurance 12
A. Flow Calibration 12
B. System Cleanliness 12
V. Data Forms 12
ERG Toxics/SNMOC Sample Data Sheet 13
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Toxics in Schools, VOC SOP
Rev. No. 2
July 21,2009
INTRODUCTION
This procedure is designed to provide instruction on collecting volatile organic
compounds in air using a canister with a passive air sampling kit.
This method is designed for the sampling of volatile organic compounds
(VOCs) in ambient air. The method is based on the collection of whole air
samples in specially treated canisters to final pressures below atmospheric.
The samples are then analyzed using EPA Compendium Methods T014A or
T015 Determination of Volatile Organic Compounds (VOCs) in Air Collected
in Specially Prepared Canisters and Analyzed by Gas Chromatography/Mass
Spectrometry (GC/MS) using the ERG contract laboratory.
The canisters are 6-liter stainless steel whose internal walls are coated to
reduce the reactivity of the air sample in the canister with an inert pure
chrome-nickel oxide compound or a silicon type compound. The canisters
contain a stainless steel treated valve equipped with a 1/4" Swagelock® fitting
on the inlet which allows for opening and closing the canister as well as for
connecting it to a wide range of sampling probes and sampling equipment.
Prior to use in the network, these canisters are purged several times with
clean humidified zero air and then checked for contamination via GC/MS.
Once certified as clean, the canisters are evacuated to approximately -30
inches of vacuum and are ready for use. The sampling method is simply a 24
hour passive sample whereby the canister is attached to a sample probe with
a timer, the valve is opened, and the canister is filled with ambient air.
This SOP is designed to be a step by step method for operating the sampling
system to be used in conjunction with the manufacturer's operator's
manual(s). Laboratory Analysis Methodology using the T015 method may be
referenced by contacting the Eastern Research Group (ERG) directly at 919-
468-7800 or by email Julie.Swift@erg.com. Maintenance and troubleshooting
should be conducted using the relevant operator's manual(s).
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Toxics in Schools, VOC SOP
Rev. No. 2
July 21,2009
FIGURE 1. Photograph of Total VOC Sampling System
With Timer and Probe
Photograph courtesy of Nutech, GD Environmental Supplies, Inc
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Toxics in Schools, VOC SOP
Rev. No. 2
July 21,2009
INSTALLATION
A. Sampler Siting
Check the areas for safety. Ensure there will be enough room for the
operator to move freely while working, and ensure physical conditions of
the location will allow the operator to work safely.
The sampler should be set in a location unobstructed from any side. No
tree limbs or other hanging obstructions should be above the sampler. It
is suggested that the horizontal distance from the sampler to the closest
vertical obstruction higher than the sampler be at least twice the height of
the vertical obstruction. There should be no sources located nearby that
may bias sampling measurements.
Locate the sampler on a reasonably level structure at a height between
two (2) and fifteen (15) meters above the ground.
B. Sampler Installation
1. The sampling system consists of three components: the sample
canister, Nutech 2701 programmable field canister timer, and
passive sampling kit which includes flow controller with pressure
gauge and sample inlet. All components will be received from the
ERG laboratory where: the cans will have been cleaned, tested for
contamination and evacuated; flow controllers will have been
cleaned, tested for contamination, and calibrated for 24 hour
sampling; and the sample inlet will have been tested for
contamination.
2. The can must be mounted on a tripod or other support structure to
ensure the probe inlet will meet the minimum siting criteria of at
least 2 meters above ground level. Additionally, the probe inlet
should be at least 2 meters above the surface that the tripod sits
to reduce the chance for contamination from travel around the
sampling system. A mounting system for the can may be fabricated
to hold the can or another system may be devised to hold the can
securely in place.
3. Attach the stainless steel flow controller/gauge/ inlet apparatus to
the top of the timer by placing it onto the fitting on the top of the
timer unit and tightening the nut using a wrench. Be very careful
when installing and performing maintenance that no grit or dirt is
introduced onto the frit. This will clog the system or render parts
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Toxics in Schools, VOC SOP
Rev. No. 2
July 21,2009
inoperable. DO NOT OVERTIGHTEN the nut. When the nut feels
snug, another quarter turn should be sufficient to secure the inlet
apparatus.
4. Attachment of the can will be discussed in Section III, C Conducting
the Sampling Event section.
5. Level the tripod/stand on site. To secure the tripod and protect
merrf brane roofs, 2x4 wooden studs may be cut into two foot
sections and fastened to the legs using lag bolts and "L" brackets.
Place sand bags on these skids to prevent tipping of the tripod.
If collocated samplers will be located at the site, the two samplers
must be within four (4) meters of each other, but outside of two (1)
meter. The inlet heights must be within one (1) meter vertically.
OPERATING PROCEDURE
A. Equipment and Supplies
6 liter sample collection canister
Stainless steel flow controller/gauge/ inlet apparatus
Nutech 2701 programmable field canister timer
Tripod or stand with holder for assembled sampling apparatus
Logbook
ERG sample paperwork
B. Sampler and Sample Media Receipt Activities
Sampling Apparatus
1. Check parts and components against the packing list.
2. Ensure all fittings are present and in good condition.
3. Prior to sampling keep all components in a clean area free of
contamination.
Nutech 2701 Programmable Field Canister Timer
1. Charge the internal battery by opening the front cover and plugging
in the supplied USB adapter into the labeled USB port located on
the bottom right of the front panel.
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Toxics in Schools, VOC SOP
Rev. No. 2
July 21,2009
2. Plug the USB adapter into a 110V AC electrical socket and allow
the unit to charge for at least 12 hours. If the internal battery is
completely drained, there may be no initial response on the display.
The battery will display [HD1 after a full charge. The display will
show 113 when the unit needs to be recharged. This battery
indicator is located at the top center left of the display.
3. After the battery is fully charged, set the current time (local standard
time) by pushing the "Set" key twice to enter time now setting.
4. The LCD will show a flashing digit(s) that can be changed. Change
the time digits by pushing the left or right arrow keys. Press the set
button to move to the day of the week.
5. Change the day by pushing the left or right arrow keys. An arrow
will be present above the selected day.
6. Press the "Enter" key to finish the time setting.
7. If the battery is fully drained during operation, the time may need to
be reset.
Sample Collection Canister
1. The sample collection canister will arrive from ERG in a cardboard
box. The canister does not need to be refrigerated after receipt or
during return shipping.
2. Open the box and ensure the canister is in good condition. Confirm
that the valve remained in the closed position during shipping and
that the top plug is secured on the top fitting.
C. Conducting the Sampling Event
Site Arrival Daily Activities
1. Check the timer battery and ensure there is at least one bar on the
display. If there is one bar or no bars, the timer should be
recharged before conducting the sampling event.
2. Record activities, site observations, and maintenance activities in
logbook.
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Toxics in Schools, VOC SOP
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July 21,2009
3. Inspect the sampling apparatus inlet checking for insects or debris
that may be present from the prior sampling event. Clean if
necessary.
Sample Recovery and Data Collection
1. Activate the timer display by pressing the "Enter" button once. This
will activate the screen with the current day of the week and current
time of day (in Standard Time not Daylight Savings Time). The
valve icon on the timer should appear as a indicating that the
valve is in the closed position. The display will also indicate the total
elapsed time for the previous sampling event.
2. Record the total elapsed time on the ERG Toxics/SNMOC Sample
Data Sheet in the "Elapsed Time" blank in the "Field Recovery"
section.
3. Open the solenoid valve by pressing the "Manual" button once.
4. Read the gauge and record the remaining pressure left in the can
on the ERG Toxics/SNMOC Sample Data Sheet and record the
reading in the "Field Recovery", "Field Final Can. Press. ("Hg)"
blank. If the pressure is zero, note the lack of pressure in the
"Comments" section of the form.
5. Close the timer solenoid valve by pressing the "Manual" button
again.
6. Close the sample canister by turning the knob or handle until it is
tight.
7. Using a wrench, loosen the nut connecting the timer to the canister,
and remove the timer and flow controller apparatus.
8. Replace the cap/nut to the top inlet of the canister "finger tight".
Using a wrench, turn the cap a quarter turn to secure.
9. On the ERG Toxics/SNMOC Sample Data Sheet, completely fill in
the rest of the "Field Recovery" section. Be sure to record any
observations that were made during the run period.
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Toxics in Schools, VOC SOP
Rev. No. 2
July 21,2009
Preparing Sampling System for a Sampling Event
1. Prepare sample paperwork. On the ERG Toxics/SNMOC Sample
Data Sheet, complete the missing information on the "Lab
PreSampling" section. Record any pertinent observations in the
notes section at the bottom of the form.
2. Remove the cap/nut covering the top of the canister using a
wrench. Set the nut aside in a clean place so that it can be retrieved
and used after the sampling event.
3. Attach canister to the Nutech 2701 timer by fitting the timer unit on
top of the canister. Tighten the nut connecting the timer to the
canister. DO NOT OVERTIGHTEN the nut. When the nut feels
snug, another quarter turn should be sufficient to secure the timer
inlet to the can. The stainless steel flow controller/gauge/ inlet
apparatus should already be connected to the timer.
4. Program the sampling event by pushing the "set" button once to
enter event setting.
5. Set event number (SEG on the display). Select 1 as your event
number using the arrow keys. Once the event number is set,
"Open" will be flashing to set the valve function.
6. Press "Enter" to confirm the open function. The time will flash. Set
the sampling start time, followed by the day of the week using the
arrow keys. Confirm the settings by pressing "Enter" to complete
the program.
7. The valve icon on the timer should appear as td indicating that
the valve is in the closed position. During the sampling event, the
icon on the timer will appear as
8. To set the event stop time, push (Set once to enter event setting. Set
event number (SEG) first. Select 1 as your event number. Once you
set the event number the (Open) will flash. Using right arrow key to
move flashing to (Close), now (Close) is flashing for you to set the
valve function. Push (Enter) to confirm the close function. Then the
time will be flashing. You now set your sampling stopping time,
followed by day of the week. Select the day of the week then push
(Enter) to finish the sampling start time.
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Toxics in Schools, VOC SOP
Rev. No. 2
July 21,2009
9. Open the solenoid valve by pressing the "Manual" button once.
10. Read the gauge and record the pressure in the can on the ERG
Toxics/SNMOC Sample Data Sheet and record the reading in the
"Field Set -up", "Field Initial Can. Press. ("Hg)" blank.
11. The pressure indication should be approximately 30 inHg. If no
pressure or if less than 20 inHg is displayed, another canister
should be used.
12. Close the timer solenoid valve by pressing the "Manual" button
again.
13. Press the "Auto" button to activate the sampling event. "Activated"
should appear in the lower left hand corner of the display.
14. Ensure that the can and sampling apparatus are securely fastened
to the tripod or stand.
Sample Shipping
If available, use a cable tie or other device to "lock" the valve handle in
the closed position. Remove the pink copy of the ERG Toxics/SNMOC
Sample Data Sheet and file in a site record. Pack the can and the
completed white copy of the ERG Toxics/SNMOC Sample Data Sheet in
the original cardboard shipping box and tape it closed. The can does
NOT need to be shipped cold. Use the pre-filled out FedEx label
provided by ERG, and fill out the "Sender" section with the sampling
agency's address and phone number. Send priority overnight to ERG.
If the shipping form is lost, use the address below for shipping to ERG,
and contact them directly for the FedEx accounting.
Address: ERG
601 Keystone Park Drive
Suite 700
Morrisville, NC 27560
919-468-7924
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Toxics in Schools, VOC SOP
Rev. No. 2
July 21,2009
IV. QUALITY ASSURANCE
To ensure that quality data is being collected the following checks should be
considered:
A. Flow Calibration
A flow calibration must be completed at the beginning of the study period.
This activity will be completed by ERG before the device is shipped to the
agency. The operator should suspect a problem if the remaining
pressure in the can is consistently zero.
B. System Cleanliness
All equipment, with the exception of the timer, will be cleaned by ERG
before shipment to the agency. If anomalies are observed, the ERG
laboratory will notify the agency and a course of action will be identified.
The operator should take care not to touch or contaminate the inlet,
fittings, and other parts of the sampling train. These areas should be
kept covered if possible when sampling is not occurring.
V. DATA FORMS
All sample related run data forms will be supplied by ERG. Check the data
sheets for completion after every setup or retrieval event. The operator is
expected to keep a logbook to document all site activities, quality assurance
activities, and sampling activities. The ERG Toxics/SNMOC Sample Data
Sheet is attached below.
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Toxics in Schools, VOC SOP
Rev. No. 2
July 21,2009
ERG Toxics/SNMOC Sample Data Sheet
ERG Lab ID *
TOXICS/SNMOC SAMPLE DATA SHEET
a
Site Code:
City/State:
AQS Code:
Canister Number:
Collection Date:
Options
SNMOC(Y/N):_
TOXICS (Y/N):
Lab Initial Can. Press. ("Hg):
Date Can. Cleaned:
Cleaning Batch # :
Duplicate Event (Y/N):
Duplicate Can # :
2 §•
.1 S
It.
Operator:
Setup Date:
Sys.
MFC Setting:
Field Initial Can. Press. {"Hg):
Elapsed Timer Reset (Y/N):
Canister Valve Opened (Y/N):
t
2 5
« 6
u
GJ
Received by:
Status: Valid
If void, why:
Date:
Void
(Circle one)
S
at
Analyst:
Batch I.D.
Date:
X
o
Analyst:
Batch I.D.
Date:
Comments:
White: Sample Traveler
Canary: Lab Copy
Pink: Field Copy
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