Hot Filament Failure
Definition
Fracture of a tungsten bulb filament while at operational temperature (2,500-3,000 K); characterised by ductile deformation at the break, coiling, and tungsten trioxide (WO3) oxidation, confirming the headlight was on at impact.
Related terms
- ASTM E2927
- Standard test method for the determination of trace elements in glass samples using LA-ICP-MS; specifies the element suite, calibration standards (NIST SRM...
- BNS 2023 § 106
- Bharatiya Nyaya Sanhita 2023 provision criminalising causing death by negligence; the primary charging provision for fatal hit-and-run cases in India, with enhanced...
- Cold Filament Failure
- Fracture of a tungsten bulb filament below operational temperature; characterised by a clean, brittle transverse fracture with no deformation and no oxide...
- EUCAP
- European Collection of Automotive Paints, maintained at the Bundeskriminalamt (BKA) in Wiesbaden; the European counterpart to PDQ for automotive hit-and-run paint comparison.
- FCIN
- Forensic Collision Investigation Network (UK); provides standardised protocols for fatal and serious-injury collision forensic examination, including paint, glass, tyre and filament examination.
- LA-ICP-MS
- Laser ablation inductively coupled plasma mass spectrometry; a technique that fires a laser pulse at a sample surface, vaporises a tiny amount,...
- PDQ (Paint Data Query)
- RCMP-maintained international automotive paint database. Stores binder, pigment and layer data for vehicle original-equipment finishes from major manufacturers. Used to narrow a...
- PVB Interlayer
- Polyvinyl butyral film bonding the two glass layers in a laminated automotive windshield; retains broken glass in place after fracture, preserving the...
- SWGTREAD
- Scientific Working Group for Shoeprint and Tire Tread Evidence; US body that developed the dominant guidelines for footwear and tyre-mark examination, class-subclass-individual...
- Treadmate
- RCMP database of outsole designs for footwear comparison, used by Canadian forensic laboratories and accessible to partner agencies.
- Tungsten Trioxide (WO3)
- Pale yellow oxide of tungsten formed rapidly at temperatures above approximately 800 K when tungsten is exposed to atmospheric oxygen; its presence...
Explained in
- Vehicle Examination: Paint, Glass, Tyre, Headlight FilamentFracture of a tungsten bulb filament while at operational temperature (2,500-3,000 K); characterised by ductile deformation at the break, coiling, and tungsten...