1. Evidence Collection

2.  ASAP – no search warrant needed initially b/c evidence can be lost quickly  Collect 3-4 L of ash and debris, plus anything with traces of accelerant  Use portable vapor detectors or arson dogs

3. Packaging  Substrate control – sample not contaminated by accelerant  Used for comparison  Packaged separately in airtight container (ex. Clean paint can) so vapors not lost - space left for vapors = headspace

4. Determining igniter  Match or lighter – often destroyed in fire or taken with culprit  Molotov cocktail – leaves glass fragments  Spark plug or fuse to ignite fire – often parts of it found

5. Criminal Profile  Clues about arsonist – type of accelerant and igniter; method of operations  Can make criminal profile = list of likely characteristics; narrows list of suspects

6. Lab Analysis  Analyze accelerant residue 1. Direct headspace extraction procedure a. heat to collect vapors in headspace b. remove w/ syringe c. gas chromatograph - Compare debris & control to see if additional chemical is present - - compare to known accelerants

7. 2. Passive headspace extraction procedure - Charcoal-coated strip suspended in headspace - Can w/ lid heated 4-16 hrs at 50-80 o C - Accelerant will vaporize & be absorbed by charcoal - Charcoal washed w/ organic solvent - Solvent dissolves & removes accelerant - Recovered accelerant -> gas chrom.