National Institute for Occupational Safety and Health

“ A silylated glass wool plug precedes the front section and a 3mm urethane foam plug follows the back section. Tubes are comm ercially available. 2. Personal sampling pump, 0.01 to 0.2 L/min, with flexible tubing. 3. Gas chromatograph, FID, integrator, and Rtx1, or equivalent, fused silica capillary column. 4. Autosampler vials, glass, 1.8 mL, with PTFElined caps. 5. Syringes, 10-μL to 1-mL. 6. Volumetric flasks, 10-mL and 250-mL. 7. Pipets, various sizes.
SPECIAL PRECAUTIONS: Carbon disulfide is toxic and flamm able. Methanol is moderately toxic and flam m able. ”

“ Inject a 1-μL sample aliquot manually using the solvent flush technique or with an autosam pler. NOTE: If peak area is above the linear range of the working standards, dilute with carbon disulfide/methanol (99:1) , reanalyze and apply the appropriate dilution factor in the calculations. 11. Measure peak areas.
CALCULATIONS: 12. Determ ine the ma ss, μg (correc ted for DE) , for p-chlorobenzotrifluoride found in the sam ple front (W f) and bac k (W b) sorbent sections, and in the averag e m edia blank front (B f) and back (B b) sorbent sec tions. ”

“ This m ethod developm ent was ba sed upo n an health hazard evaluation request where p-chlorobenzotrifluoride was being us ed as a clean ing solvent for auto m obile parts. After an evaluatio n of va rious solid sorbent tubes and solvent/solvent m ixtu res, c oconut s hell charcoal tubes and carbon disulfide/m eth anol (99:1) solvent were selected for use in this method development. The desorption efficiency (DE) was determined for p-chlorobenzotrifluoride at 4 levels ranging from 27.1 μg to 541.2 μg. The average DE de termined for pchlorobenzotrifluoride was 100.6%. ”