Determining the presence of accelerants after a fire
The RAE MR2000 portable PID VOC detector detects the presence of accelerants. Accelerants are VOCs. After there has been a fire, there will still be higher levels of VOCs at the source of a fire when accelerants have been used that otherwise would be the case when accelerants are not used.
The procedure would be to hold the end of the PID probe at the point where accelerant may be present and watch or listen to the PID for any sign of hydrocarbons. Check at joints or cracks between boards, under baseboards or plates in contact with flooring. Pry up boards to form a small crack where the PID probe can be inserted. Also check under unburned portions of rug or upholstery or any point where accelerant may have soaked in and remained. Concrete floors can also hold a high amount of residual accelerant. If elevated levels of hydrocarbon contamination are detected, trace it to the point of maximum reading. This is the point where samples should be taken for further lab analysis.