What is ignitable liquid residue?
Ignitable liquid residue (ILR) is the evidence left behind at the scene of a fire. ILR represents the portion of an ignitable liquid that did not burn during a fire. The simple presence of ILR at the site of an arson investigation does not necessarily mean that the fire was deliberately started.
Which technique among the following is the most specific for the identification of ignitable liquids?
Gas chromatography-mass spectrometry is the most widely used analytical technique for the determination of accelerants in fire debris.
What is some evidence that an ignitable liquid was used to start a fire?
Evidence of the use of a flammable liquid in a fire can be established by an examination of burn patterns, charring, melted metals, heat colors, glass, observations of fire fighters, and the presence of residual flammable or combustible vapors.
What is an ignitable liquid accelerant?
Many accelerants are hydrocarbon-based fuels, sometimes referred to as petroleum distillates: gasoline, diesel fuel, kerosene, turpentine, butane, and various other flammable solvents. These accelerants are also known as ignitable liquids. Ignitable liquids can leave behind tell-tale marks in the fire debris.
How are materials collected at the scene analyzed to test for the presence of ignitable liquids?
Most materials analyzed for ignitable liquids are done using a three-step process: extraction of volatile compounds from the submitted material, separation, and detection of those volatile compounds, and data analysis to identify those compounds and their possible source.
How does the charcoal coated strip aid in analysis?
Activated charcoal strips are used to maximize the containment of accelerants at fire scenes. The introduction of commercially produced activated charcoal strips into fire debris analysis has provided an easy, efficient and cost effective method for accelerant extraction.
What are some indicators of use of accelerants in an arson fire?
Physical indicators used to detect the presence of accelerants are localised burn patterns to floors and surfaces and overhead damage inconsistent with the naturally available fuel. Reports from fire fighters or eyewitnesses of a rapid fire or of suspicious odours can also indicate the presence of an accelerant.
What is the flash point of combustible liquid?
Flammable liquids have a flash point of less than 100°F. Liquids with lower flash points ignite easier. Combustible liquids have a flashpoint at or above 100°F.
Are all accelerants are ignitable liquids?
What does an accelerant do? Sometimes it is hard to find evidence at the scene of a suspicious fire because the act of putting out a fire is destructive. All accelerants are ignitable liquids.
What are 3 ways investigators identify accelerants?
Signs that an arson investigator may find at the scene of a fire after it’s extinguished are rainbow colors along the surface of liquids remaining at the scene, burn patterns that indicate the presence of an accelerant, a window that’s clean of soot on the fire side but melted, or any indication that a fire burned …
What 2 things are used to detect accelerants?
Two types of hydrocarbon chemical tests have been used for accelerant detection. Draegar tubes are routinely used for detecting hydrocarbons in the atmosphere and hydrocarbon field test kits are used for soil and water analysis and both have been used at fire scenes.
