SAMPLING:
NOTE: Prior to field use, clean all thermal desorption tubes thoroughly by heating at or above the
intended tube desorption temperature for 1-2 hours with carrier gas flowing at a rate of at least
50 mL/min. Always store tubes with long-term storage caps attached, or in containers that
prevent contamination. Identify each tube uniquely with a permanent number on either the
tube or tube container. Under no circumstances should tape or labels be applied directly to
the thermal desorption tubes.
1. Calibrate each personal sampling pump with a representative sampler in line.
2. Remove the caps of the sampler immediately before sampling. Attach sampler to personal sampling
pump with flexible tubing.
NOTE: With a multi-bed sorbent tube, it is extremely important to sample in the correct direction, from
least to maximum strength sorbent.
3. For general screening, sample at 0.01 to 0.05 L/min for a maximum sample volume of 6 L. Replace
caps immediately after sampling. Keep field blanks capped at all times. Tubes can act as diffusive
samplers if left uncapped in a contaminated environment.
4. Collect a "humidity test" sample to determine if the thermal adsorption tubes have a high water
background.
NOTE: At higher sample volumes, additional analyte and water (from humidity) may be collected on
the sampling tube. At sufficiently high levels of analyte or water in the sample, the mass
spectrometer may malfunction during analysis resulting in loss of data for a given sample.
5. Collect a "control" sample. For indoor air samples this could be either an outside sample at the same
location or an indoor sample taken in a non-complaint area.
6. Ship in sample storage containers at ambient temperature. Store at -10 C.
SAMPLE PREPARATION:
7. Allow samples to equilibrate to room temperature prior to analysis. Remove each sampler from its
storage container.
SAMPLING:NOTE: Prior to field use, clean all thermal desorption tubes thoroughly by heating at or above theintended tube desorption temperature for 1-2 hours with carrier gas flowing at a rate of at least50 mL/min. Always store tubes with long-term storage caps attached, or in containers thatprevent contamination. Identify each tube uniquely with a permanent number on either thetube or tube container. Under no circumstances should tape or labels be applied directly tothe thermal desorption tubes.1. Calibrate each personal sampling pump with a representative sampler in line.2. Remove the caps of the sampler immediately before sampling. Attach sampler to personal samplingpump with flexible tubing.NOTE: With a multi-bed sorbent tube, it is extremely important to sample in the correct direction, fromleast to maximum strength sorbent.3. For general screening, sample at 0.01 to 0.05 L/min for a maximum sample volume of 6 L. Replacecaps immediately after sampling. Keep field blanks capped at all times. Tubes can act as diffusivesamplers if left uncapped in a contaminated environment.4. Collect a "humidity test" sample to determine if the thermal adsorption tubes have a high waterbackground.NOTE: At higher sample volumes, additional analyte and water (from humidity) may be collected onthe sampling tube. At sufficiently high levels of analyte or water in the sample, the massspectrometer may malfunction during analysis resulting in loss of data for a given sample.5. Collect a "control" sample. For indoor air samples this could be either an outside sample at the samelocation or an indoor sample taken in a non-complaint area.6. Ship in sample storage containers at ambient temperature. Store at -10 C.SAMPLE PREPARATION:7. Allow samples to equilibrate to room temperature prior to analysis. Remove each sampler from itsstorage container.
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