Standard Practice for Static Headspace Sampling of Vapors from Fire Debris Samples

Abstract

4.1 This practice is intended for use as a sampling technique within a general scheme for the analysis of ignitable liquids and ignitable liquid residues from fire debris samples in accordance with Guide E3245. 4.2 Headspace samples obtained using this practice are screened using a gas chromatograph with a flame ionization detector (GC-FID) or analyzed using a gas chromatograph with a mass spectrometer (GC-MS, refer to Test Method E1618). 4.3 This practice is most applicable for sampling light to medium range ignitable liquids.3, 4, 5, 6 It is not capable of sufficient recovery of heavy range ignitable liquids to support accurate analysis using Test Method E1618. Note 1: When present in high concentrations, highly volatile compounds can saturate the headspace, inhibiting the recovery of less volatile compounds by this practice. This skewed recovery can lead to the detection or identification of only the more volatile compounds in the sample. 4.4 This practice is useful for sampling fire debris to screen for the presence of ignitable liquid residues prior to extraction with other techniques, such as those described in Practices E1386, E1412, E1413, and E2154, and E3189. 4.4.1 This practice is less capable of recovering limited quantities of ignitable liquids than Practices E1386, E1412, E1413, E2154, and E3189, particularly for heavy range compounds. 4.5 This practice only removes a small aliquot of the headspace vapor from a closed container; therefore, the fire debris sample remains in approximately the same condition in which it was submitted, and reanalysis using a new headspace sample, or a different sampling technique, is possible. However, removing multiple headspace samples continually reduces the concentration of ignitable liquid vapors, if originally present, and can eventually result in non-recovery by static headspace sampling. Note 2: The headspace sample collected using this practice is consumed in the subsequent screening by GC-FID or analysis by GC-MS.