Significance and Use
5.1 The preservation and storage of extracts recovered from fire debris or liquids submitted in a fire investigation provides a mechanism for reanalysis in the event that the original evidence is altered due to factors such as the extraction process (Practices and ), sample degradation, or failure of the original evidence container during post-analysis storage.
5.2 Reanalysis of a stored sample extract could result in data that do not duplicate the data obtained during the initial analysis. Loss of the more volatile components of a stored sample can occur, and this possibility should be considered when interpreting data from a stored sample. Studies of gasoline and diesel show that results (that is, determination of presence and classification of an ignitable liquid, or determination of absence of an ignitable liquid) obtained from reanalysis data are in agreement with the initial analytical results. ()
5.3 Preserved extracts are either returned to the submitter for storage or catalogued and stored by the laboratory or other designee.
1.1 This standard covers procedures for the preservation of ignitable liquids and ignitable liquid residue extracts obtained from fire debris samples and questioned ignitable liquid samples. Extraction procedures are described in Section , Referenced Documents.
1.2 Specific evaluation of this practice is limited to the preservation of gasoline and diesel fuel (, ) the components of which together span the range of chemical classes and volatility of ignitable liquid residues commonly encountered in fire debris samples.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.