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Crime Scene Investigation for Explosive Incidents. Prof. Charles L. Feer Department of Criminal Justice. Bomb Scene Investigations. Start as Local L.E. Investigation F.B.I. investigates Terrorism A.T.F. & E. investigates explosives E.O.D. (Bomb Techs)
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Crime Scene Investigationfor Explosive Incidents Prof. Charles L. FeerDepartment of Criminal Justice
Bomb Scene Investigations • Start as Local L.E. Investigation • F.B.I. investigates Terrorism • A.T.F. & E. investigates explosives • E.O.D. (Bomb Techs) • Be Aware of Secondary Devices! MadridIraq • Do not enter until told “safe” • Assessing safety is on-going. Turkey News Turkey 2
Explosion An explosion is: • A sudden and rapid escape of gases from a confined space. • Accompanied by high temperatures, violent shock, and loud noise. Pipe Bomb
Three Types of Explosions • Mechanical • Chemical • Nuclear
Mechanical Explosion • Occurs when pressure builds up in a container until the pressure exceeds the structural resistance of the container. Alley Effect
Chemical Explosion • Are the result of fuel and oxygen supporting rapid combustion. Redneck Bomb Maker
Atomic Explosions • Are produced by Fission – splitting the nuclei of atoms; or, • Fusion which forces the nuclei of atoms together under great pressure.
Energetic Materials Two broad categories of Explosions: • 1) Low Explosives – burn rather than explode. (Need to be contained) • 2) High Explosives – detonate by shock. (Do not have to be confined.)
High Explosives Three groups: • Primary – detonate forcefully, sensitive to heat, shock, friction. • Secondary - require a detonating device or initiating explosion. • Tertiary – require a booster or a secondary high explosive to detonate.
Upon Detonation 1) Shock wave moves. Slow Mo Pressure 2) Air rushes back into void created by positive pressure. Positive – Negative Pressure 3) Fragmentation (container) and Shrapnel (attached to bomb). Flying – LEFlying – Iraq
Locating and Collecting Evidence • Do NOT go in without a Bomb Tech! • Locate Crater – indicates the origin of the blast. • Soil samples must be gathered from all areas surrounding the crater. • Locate remnants of the detonating mechanism.
Locating and Collecting Evidence • Remnants can include blasting caps, batteries, match heads, cell phones, walkie-talkies, timers. • Think – Fingerprints! • Think – DNA!
Locating and Collecting Evidence Indoor Scene – Each room should be treated as a separate crime scene. Outdoor Scene – Locate the debris furthest from the crater, and double the distance for your perimeter. If a suspect is arrested – collect all clothing and personal items. (Seal everything in paper bags.)
Explosive Incidents • Think Hazardous Materials! • Transportation of Haz-Mat materials, including explosives require special conditions.