Module details for Firearms, Fires and Explosions

Description

Examines the investigation, evaluation and interpretation of evidence from firearms, fires and explosions. It examines causes of fire, thermodynamics of combustion, sample collection and packaging, chemical tests and analytical techniques for fire debris analysis. It explores the nature of explosives and explosions, blast wave propagation, damage caused and the forensic evidence. We will cover internal, external and terminal ballistics and evidence from firearms discharge, recovered bullets and cartridge casing, and consider crime scene to court presentation and interpretation.

Aims

The aims of this Module are to enable the student to: (i) examine and characterise the origin of fire/explosion debris; (ii) evaluate techniques for distinguishing residues, (iii) identify the source and subsequent history of samples, (iv) understand the principles of kinetics/dynamics, energetics, phase transfer, and (v) the interpretation and understanding of ballistics evidence.

Learning Outcomes

By the end of this module the student should be able to:

1.  Apply the principles of kinetics and thermodynamics to fires and explosions

2.  Critically interpret findings of fire investigations in relation to fire dynamics

3.  Characterise explosives, fire debris and firearms discharge residue

4.  Evaluate forensic firearm and ballistic examinations

5.  Conduct and critically interpret a range of relevant laboratory techniques.

Indicative Content

1 Fire and Explosion Dynamics

Heat transfer mechanisms, ignition and spread of flame, spontaneous and smouldering combustion, pre-and post-flash-over fires, smoke movement, buoyancy, fuel load.

2 Thermochemistry of Fuels and Explosives

Combustion and energy release, oxygen balance and the Kistiakowsky−Wilson rules, Hess's law, heat and temperature of explosion, the concept of heat capacity.

3 Explosion and Fire Debris analysis

Explosives classification, factors affecting detonation. Debris position, identification of mechanical, thermal history and origin. Use of chemical tests to identify potential explosive residues and accelerants. Fire cause diagnosis, identification of origin of fire and source of ignition.

4 Internal, External and Terminal Ballistics

Factors affecting velocity, trajectory and impact of ballistic weapons, wounding, permanent and temporary cavity production factors.

5 Ballistic physical evidence

Tool-marks, firing pin impressions, rifling striations, gunshot residue, class and individual characteristics, factors affecting evidence production, transfer and persistence and interpretation.

Teaching and Learning Work Loads