National Institute for Occupational Safety and Health

“ Add known amounts of calibration stock solution, or serial dilutions thereof, to hexane in 10-mL volumetric flasks and dilute to the mark.
NOTE: The working standards are stable indefinitely at room temperature if kept in airtight containers. Analyze together with samples and blanks (steps 12 and 13) . Prepare calibration graph (peak area or height vs. μg pentachloroethane) . Determine desorption efficiency (DE) at least once for each lot of Porapak R used for sampling in the calibration range (step 9) . ”

“ Hexane is flammable (flash point = -21 °C) and toxic; all work with it must be done in a hood.
Pentachlorothenae causes CNS effects, with possible liver and kidney effects [3] . Technical grade pentachloroethane (containing 4.2% hexachloroethane, a known carcinogen in mice) was carcinogenic for B6C3F1 mice, causing hepatocellular carcinomas in males and females, and adenomas in females [4] .
SAMPLING:
Calibrate each personal sampling pump with a representative sampler in line. ”

“ INTERFERENCES: 1,2,2,3-Tetrachloropropane interferes with the analyte GC peak but is not likely to be present in most samples. Large concentrations of 1,1,2,2-tetrachloroethane may obscure the analyte GC peak. ”