NFPA 1033 Job Performance Requirements: Fire Investigator
What this domain tests
NFPA 1033 is the Standard for Professional Qualifications for Fire Investigator. The exam tests the investigator's JPRs: applying the scientific method, examining the scene, determining origin and cause, handling evidence, interviewing, documenting, and testifying. The standard defines what a competent investigator must know and be able to do; it does not teach fire science.
Core rules
- The general JPRs require the investigator to use the scientific method: identify the problem, define it, collect data, analyze data, develop hypotheses, test them against the data, and select the hypothesis that survives testing.
- Origin before cause. The investigator first locates the area of origin, then evaluates ignition sources, fuels, and circumstances.
- Required knowledge includes fire science, building construction, fire protection systems, electricity, human behavior, evidence, and legal issues.
- Evidence JPRs: recognize, document, collect, package, preserve, and transfer evidence; maintain chain of custody; prevent contamination and loss.
- Scene safety is a continuing duty: structural stability, utilities, PPE, air monitoring, and rekindle potential.
- The investigator must remain current in the field and produce reports and testimony supported by data, not assumption.
Worked example
An investigator finds a V-pattern and a low burn area with a possible ignitable-liquid pour. Rather than declaring arson, the investigator documents the pattern, collects a sample from the proper depth in an approved container, submits a comparison or blank as appropriate, records the chain of custody, and tests the ignitable-liquid hypothesis against other sources, such as a failed appliance or spilled fuel. The reasoning is that a pattern is data, not a conclusion; cause is established only after hypotheses are tested.
Traps
Calling the origin the cause. Using 'negative corpus'-ruling out accidental causes without affirmative evidence. Skipping documentation or chain-of-custody entries. Assuming a pour pattern proves an ignitable liquid. Ignoring safety hazards during examination.