The science of fire origin and cause investigation can be a verycomplex subject. No two fires are ever alike and therefore, everyfire investigation has its own particular set of challenges.However, regardless of whether the investigation is for a smallvehicle fire or a large commercial loss, many of the steps used incompetent fire investigation are the same.

NFPA 921, the National Fire Protection Guide for Fire &Explosion Investigations, is a guide that outlines the acceptedapproach and methods used in fire investigation. The basicprinciples incorporated center around the scientific method. Thescientific method involves some very specific steps, beginning withidentifying the problem and concluding with the selection of afinal hypothesis.

It is critical to origin and cause investigations that ahypothesis not be developed until all of the data has beenthoroughly and completely collected and analyzed. Conducting aninvestigation based on any preconceived notions or ideas is a trapthat must be avoided at all costs. You cannot try to make the data“fit” your theory. It can lead to missed evidence, overlookedinformation, or unnoticed facts, and is ultimately likely to bedisproven.