Fire Flashcards
(23 cards)
What are indoor fires called?
Compartment fire
What are the thee stages of compartment fires and describe them
- Open fire:
- Growth
- Flashover
-> Fully developed fire: burning all combustible materials
What does the black smoke come from?
Whats happening as the couch is melting?
more gases are coming up from it melting that it can cause a rollover
petroleum products
What do you determine in an Ignitable liquid residue analysis?
Does not determine origin or cause of fire, simply if there is an ignitable liquid present
ILR are classified not identified
Petroleum:
Non petroleum: nail polish remover
Characteristic compounds - what you are looking for in a chromatogram
- ## aromatics-
Subclasses
- terpines (natural solvents)
- alt fuels
- cooking oils (fatty acids)
- oxygenates: alchohol, acetone (GCMS does not pick up n these very well, req a special method if its suspected)
Why is it important to package this evidence in airtight can/cont
volitile
all evidience escapes
Accelerant
material used to promote or spread a fire
Ignightable liq
any liq that readily burns
Adsorption
adherace of molecules of a gas or liq to the SURFACE of substrate
Elution
Theres another one i didnt get
PID Photoionzation detector (electronic sniffer)
detects hydrocarbons
- very broad
- increase or decerased signal
- con: other burn material can cause an increase signal = collect a lot of samples
Canines
trained to not alert burned material only those w ILR
- dectect VOC volitile orgo comp
How do you find controls in these
if dog alerts to a piece of drywall and not to another, the other piece of drywall can be used s a control
Heating
- more compounds in headspace
- combustion = loss of compounds?
Make sure library matches extraction meth
alcane ladder to see if your thing shifted ?
selected ion vs total ion?
