5.1 This practice provides best practices to be followed in the collection and preservation of OGSR samples intended for forensic analysis.

5.1.1 This practice applies to the collection of OGSR from surfaces in both field and laboratory settings.

5.1.2 Adhesive tape lifting is suitable for collecting OGSR from many dry surfaces, including skin, hair, and clothing (1-4).3

5.1.2.1 Other OGSR collection techniques such as swabbing, and vacuuming have been reported but they are not recommended for routine practice.

5.2 Gunshot residue (GSR) examinations are commonly performed to determine if an individual could have been exposed to firearm discharge. Traditional GSR analysis has relied upon the detection of pGSR, as described in Practice E1588; however, OGSR provides information that complements pGSR analysis (1, 5). This standard practice is of use to forensic laboratories desiring to supplement pGSR analysis with OGSR analysis to identify surfaces exposed to gunshot residue.

5.3 OGSR originates from the combustion of the smokeless powder and the priming mixture following their ignition during the firearm discharge process. After a firearm has been discharged, the combined residue can be found on exposed surfaces in the vicinity of the fired weapon (for example, hands, other exposed skin surfaces, hair, clothing) (2, 5). OGSR can also be found in the cartridge case after firing and can be recovered to provide information about the constituents of the propellant or the priming mixture, or both.

5.4 This standard practice does not apply to the analysis or interpretation of OGSR, or pGSR.

1.1 This practice covers procedures for the sampling and preservation of organic gunshot residues (OGSR) recovered from hands, skin, clothing, and other surfaces.

1.2 This practice is intended for use by competent forensic science practitioners with the requisite formal education, discipline-specific training (refer to Practice E2917), and demonstrated proficiency to perform forensic casework.

1.3 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.

1.4 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.