Qualified ≠ Experienced: junk science is out, real fire science is in.

We have been asked to review fellow fire investigators’ work, and something keeps showing up. There is a lack of science-backed knowledge from people who have been in the industry for three decades or more. They are considered “experts,” but many have not stayed up to date with changes in the science. That got us thinking: how many are out there still operating as forensic fire investigators on reputation alone? The uncomfortable answer is “too many,” and the evidence is in their methods. Origin and Cause (O&C) is also not a side-skill for retired firefighters or a bolt-on for generalist forensic engineers.

Modern O&C work is science-based, evidence-led, and hypothesis-driven, utilising the scientific method to build and test competing explanations before selecting a cause. That is the core expectation set by NFPA 921 and mirrored in training worldwide, even if the documents themselves are American. If your expert cannot show that workflow clearly, you are buying an opinion rather than an investigation.

For years, “rules of thumb” like crazed glass, spalling, and simple V-pattern shortcuts were treated as proof of arson. Research and practice have overturned those heuristics. Crazing is produced by rapid cooling, commonly when water hits hot glazing, not by rapid heating or an accelerant. That single example illustrates the larger shift from lore to testable fire science. Junk science is out. Real science is in.

Qualification is more than years on the truck or years in a lab. The widely used pairing is NFPA 1033 for minimum professional qualifications and NFPA 921 for how investigations are conducted. 1033 requires current, beyond-secondary knowledge across the well-known “Big Sixteen” domains, including fire science and chemistry, thermodynamics and thermometry, fire and explosion dynamics, computer modelling, methodology, hazardous materials, failure analysis, fire protection systems, evidence handling, and electrical systems. 921 requires you to apply the scientific method on every case and to accept “undetermined” when more than one cause hypothesis remains viable. These are universal quality controls that travel well across jurisdictions.

Experience still matters, but it must be coupled with education and method. A veteran firefighter or a strong forensic engineer does not automatically possess the competencies to determine origin and cause. Private clients should verify that any investigator demonstrates 1033-style knowledge coverage and a 921-style plan that explains how hypotheses will be developed, tested, and either eliminated or sustained. If you cannot follow the chain from observations to analysis to conclusion, a judge will struggle too.

Certifications can help, but they are not the finish line. IAAI and NAFI align their programs with 1033 and 921, providing widely recognised credentials; however, you should still look for applied competence. Ask for scenario-based examples, peer-reviewed reports, and proof of continuing education in emerging hazards like lithium-ion systems and electric vehicles. Treat the certificate as a starting point and verify the person behind it.

Globally, fire science is a multidisciplinary field with an international literature. Foundational technical works complement investigation guides and help keep practitioners current as fuels, systems, and buildings evolve. Serious investigators treat competence as permanent homework. If someone claims they have learned everything about O&C, they should retire.

Bottom line. Hire for education, method, and transparency, not just title or mileage. Before you engage a private investigator, check their documented 1033 knowledge footprint and demand a 921-style hypothesis test plan. If the matter goes to court, you do not want to be defending a cause opinion built on outdated heuristics or a generalist résumé.