ASTM International Standard Guide for Forensic Analysis of Geological Materials by Scanning Electron Microscopy and Energy Dispersive X-Ray Spectrometry ASTM E3501-25

1.1 This guide covers recommended techniques and procedures for the use of Scanning Electron Microscopy/Energy Dispersive X-ray Spectrometry (SEM/EDS) for the forensic analysis of geological materials to include soils, rocks, sediments, and materials derived from them (for example, concrete). 1.2 This guide describes some options for sample handling and preparation of specimens, instrument operating conditions, spectral and image data collection, evaluation of data quality, interpretation of EDS spectra for the identification of inorganic geological materials, documentation of morphology by SEM imaging, and criteria for sample comparison. 1.3 This guide 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. 1.4 The values stated in SI units are to be regarded as standard. Other units are avoided, but photon energy is commonly reported in units of kiloelectronvolts (keV), data are collected as counts per second (cps), and compositional data based on EDS are reported in elemental weight percent (wt.?%). 1.5 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. 1.6 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.