Characterization of Pyrotechnic Reaction Residue Particles by SEM / EDS

ABSTRACT: Today the most reliable method for detecting gunshot residue is through the combined use of scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). In recent years, this same methodology is beginning to find use in detecting and characterizing pyrotechnic reaction residue particles (PRRP) whether produced by explosion or burning. This is accomplished by collecting particulate samples from a surface in the immediate area of the pyrotechnic reaction. Suspect PRRP are identified by their morphology (typically 1 to 20 micron spheroidal particles) using a SEM and then analyzed for the elements they contain using X-ray EDS. This can help to identify the general type of pyrotechnic composition involved. Further, more extensive laboratory comparisons can be made using various known pyrotechnic formulations.

Keywords: pyrotechnic reaction residue  particle, PRRP, gunshot residue, GSR, scanning electron microscopy, SEM, energy dispersive spectroscopy, EDS, morphology, X-ray elemental analysis