Full Description

1.1This practice covers the analysis of gunshot residue (GSR) by scanning electron microscopy/energy-dispersive X-ray spectrometry (SEM/EDS) using manual and automated methods. The analysis may be performed manually, with the operator manipulating the microscope controls and the EDS system software, or in an automated fashion, where some amount of the analysis is controlled by pre-set software functions. This practice refers to the analysis of electron microscopy stubs and does not address sample collection (1).2

1.2Since software and hardware formats vary among commercial systems, guidelines will be offered in the most general terms possible. For proper terminology and operation, consult the SEM/EDS system manuals for each instrument.

1.3The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.4This practice offers a set of instructions for performing one or more specific operations. This practice cannot replace knowledge, skill, or ability acquired through appropriate education, training, and experience and should be used in conjunction with sound professional judgment.

1.5This practice does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user when applying this practice to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.