4.1 This practice is useful for preparing extracts from fire debris for later analysis by gas chromatography-mass spectrometry (GC/MS).

4.2 This is a very sensitive separation procedure, capable of isolating quantities smaller than 1 μL of ignitable liquid residue from a sample.

4.3 This practice is particularly useful when the potential for fractionation during separation must be reduced, as when attempting to distinguish between various grades of fuel oil.

4.4 This practice is particularly useful for the extraction of nonporous surfaces such as glass, or the interior of burned containers. It is also particularly well suited to the extraction of ignitable liquid residues from very small samples, very large samples, or samples that are not suitable for heating.

4.5 This practice is not specific to ignitable liquids and can be hampered by coincident extraction of interfering compounds present in the fire debris samples.

4.6 This practice may not be useful for the extraction of some extremely volatile ignitable liquids, which may evaporate during the concentration step.

4.7 This is a destructive technique. Whenever possible, this technique should only be used when a representative portion of the sample can be preserved for reanalysis. Those portions of the sample subjected to this procedure may not be suitable for resampling. If destruction of the sample is an issue, consider using passive headspace concentration as described in Practice E1412.