National Institute for Occupational Safety and Health

“ Determine the length of transfer line needed from the column end fitting to the bottom of the detector jet. Force a piece of 1.6-mm OD PTFE tubing equal to this length plus the length of the PTFE plug, through the center to the back end of the plug. Insert the PTFE plug, back end first, into the opening at the detector end of the column. Push the compression fitting over the column where the PTFE plug was inserted. Attach the column to the chromatograph, pushing the transfer line as close as possible to the bottom of the detector jet. Gently tighten the compression fitting around the column. ”

“ The working range is 0.1 to 4.8 ppm (0.33 to 17 mg/m3) for a 3-L air sample. However, coadsorbed water vapor will decompose the analyte unless the samples are refrigerated immediately after collection. INTERFERENCES: Acetone, methyl methacrylate and methanol do not interfere with the analysis. Methacrylamide does not elute from the column under the conditions given above. The gas chromatograph must be modified to eliminate contact of analyte with heated glass or metal surfaces. OTHER METHODS: This method was originally designated P&CAM 340 [2] . ”

“ Analyze three quality control blind spikes and three analyst spikes to ensure that the calibration graph and DE graph are in control. MEASUREMENT: 12.
Set gas chromatograph according to manufacturer’s recommendations and to conditions given on page 2506-1. ”