KBC fire investigation experts have encountered a number of fire cases recently where the prosecution investigators have erroneously implied that ‘accelerants’ were present at the scene due to ‘hits’ or ‘indications’ from sniffer dogs or hand held hydrocarbon detectors.
A recent piece of research carried out by the Bureau of Alcohol Tobacco and Firearms (ATF) in the US on hand held detectors (Fire & Arson Investigator, April 2016, Vol 66, Issue 4 P21) concluded that ‘Given the problems identified in this study, [hand held] hydrocarbon detectors are proven to be often inaccurate, and at best, should only be used as a preliminary screening tool’.
KBC’s position, and current best practice, is that only a proper laboratory examination of appropriate debris samples will confirm the presence of significant levels of hydrocarbons and therefore potential accelerant use. Even then, the presence of many hydrocarbons can have perfectly innocent explanations, from materials legitimately present or from pyrolysis/combustion products. It is imperative that analytical results are obtained and carefully considered in the context of each case.
Alan Henderson, Keith Borer Consultants