Liability in a nighttime car crash can depend on whether or not a vehicle’s lights were on or off. Hot shock is the common name for analysis of physical evidence often available that can prove if a vehicle’s lights were on or off at the time of a collision. 

Vista Engineering’s in-house scanning electron microscope (SEM) can look even more closely than standard forensic analysis described above. When clients look to us for Hot Shock SEM Analysis, we can magnify the filament much more to observe microscopic debris of glass and plastic that actually melt to the filament  when lights are on, and the filament is hot. 

Forensic SEM analysis can be performed on headlights, brake lights and other incandescent bulbs with filaments. Modern lighting systems include light emitting diodes (LEDs) and do not have heavy coiled filaments and therefore do not yield the same kind of forensic information as incandescent bulbs. Light bulb evidence is also very fragile and should be preserved early by examining and/or carefully extracting the bulbs soon after the crash. Attempts to activate a car’s electrical system to test other vehicle or safety systems can spoil lightbulb filaments and should not be done until the lightbulb evidence has been collected.