ASTM E1588
Definition
ASTM International standard practice for gunshot residue analysis by scanning electron microscopy with energy-dispersive spectrometry. Defines particle classification (characteristic, consistent-with, indicative), morphology criteria (spheroidal, fused, 0.5 to 10 micrometre), elemental panels (classical Pb-Sb-Ba and lead-free variants), and reporting language. The Indian CFSL GSR SOPs are aligned to this standard.
- Analytical Method
- Scanning electron microscopy with energy-dispersive X-ray spectrometry (SEM-EDS)
- Characteristic GSR Elements
- Lead, barium, and antimony (Pb-Sb-Ba)
- Particle Size Range
- 0.5 to 10 micrometres
- Particle Shape
- Spheroidal (rounded from melt-cooling)
Common questions
What does ASTM E1588 define for GSR analysis?+
ASTM E1588 is the standard practice for gunshot residue analysis by scanning electron microscopy with energy-dispersive X-ray spectrometry (SEM-EDS). It defines particle classification, morphology criteria, elemental detection rules, sampling procedures, and how to report results.
How does ASTM E1588 classify GSR particles?+
The standard defines three particle types. Characteristic particles contain lead, barium, and antimony together. Consistent-with particles have any two of these three elements. Indicative particles contain only one of the three elements but have morphology consistent with GSR. The standard also specifies that GSR particles should be spheroidal in shape and range from 0.5 to 10 micrometres in size.
Why is ASTM E1588 important in forensic labs?+
This standard provides consistent criteria for GSR examination across laboratories. It ensures that analysts use uniform methods for sampling, instrument setup, particle identification, and result reporting, making GSR evidence more reliable and defensible in casework.
Related terms
- Back-Scattered Electron (BSE)
- High-energy electron from the primary beam that has bounced elastically off a nucleus and exited the sample. BSE yield increases with atomic...
- Secondary Electron (SE)
- Low-energy electron (below 50 eV) ejected from the top few nanometres of the sample when the primary beam knocks a loosely bound...
- Sputter Coating
- Vacuum-deposition technique that lays a thin (5 to 15 nm) conductive layer of gold, gold-palladium or carbon onto a non-conductive sample (polymer,...
- Antimony Sulphide
- Sb2S3, the primary fuel in conventional primer formulations, burning rapidly in the presence of oxygen released by barium nitrate during ignition.
- Automated Particle Search (APS)
- A software-driven SEM mode that scans the entire stub surface using backscattered electron contrast, flags particles above an atomic-number threshold, and triggers...
- Barium Nitrate
- Ba(NO3)2, the oxidiser in conventional primer formulations, decomposing thermally to release molecular oxygen that sustains the combustion of antimony sulphide fuel.
- Characteristic Particle
- ASTM E1588 category: a single particle in which Pb, Sb, and Ba are simultaneously detected by EDS, with morphology consistent with melt-and-quench...
- Characteristic X-Ray
- An X-ray photon emitted when an outer-shell electron drops into an inner-shell vacancy created by ionisation. Energy is set by the difference...
- Consistent Particle
- ASTM E1588 category: a particle containing two of the three primer elements (Pb-Sb, Pb-Ba, or Sb-Ba), or all three elements without spherical...
- Dermal Nitrate (Paraffin) Test
- Historical test where molten paraffin was cast on the suspect's hand and the cast was sprayed with diphenylamine in sulphuric acid. Blue...
- EDS / EDXRF Detector
- Silicon-drift detector mounted at a fixed take-off angle to the sample that reads characteristic X-rays emitted as the primary beam ionises atoms...
- Energy-Dispersive X-Ray Spectroscopy (EDS)
- An X-ray detection method that simultaneously measures the energies of all characteristic X-ray photons emitted from the interaction volume, identifying all elements...
Explained in these topics
- Electron Microscopy: SEM, TEM and EDSThe ASTM International standard for gunshot residue examination by SEM-EDS, specifying stub collection, instrumental conditions, the three-element Pb-Sb-Ba cri...
- Gunshot Residue (GSR) Analysis: Detection MethodsASTM standard guide for GSR analysis by SEM-EDX. Defines characteristic particles (Pb-Ba-Sb together), consistent particles (any two of three) and the morpholo...
- Gunshot Residue: Three-Component Particles and SEM-EDXStandard Practice for Gunshot Residue Analysis by Scanning Electron Microscopy/Energy Dispersive X-Ray Spectrometry. Defines sampling, stub preparation, SEM-ED...
- Scanning Electron Microscopy (SEM) with EDXRFASTM International standard practice for gunshot residue analysis by scanning electron microscopy with energy-dispersive spectrometry. Defines particle classif...