Undetermined (NFPA 921)
Definition
The NFPA 921 conclusion category that records insufficient evidence to establish origin or cause at the 'possible' level or above. Represents the scientifically honest conclusion when data is insufficient, not an investigative failure.
- Standard
- NFPA 921 conclusion category
- Confidence level
- Below 'possible' on the NFPA 921 certainty scale
- Meaning
- Insufficient evidence for origin or cause determination
- Status
- A valid scientific conclusion, not a failure to investigate
Common questions
How does this differ from the 'undetermined cause' classification specifically?+
The NFPA 921 undetermined category can apply to origin as well as cause and marks any point on the certainty scale where the evidence falls below the 'possible' threshold, while undetermined cause is the narrower case of cause specifically not being identifiable.
Can a fire investigator later revise an undetermined finding?+
Yes, if new physical evidence, witness information, or laboratory results become available, an investigator can reopen and revise the conclusion, since undetermined reflects the state of the evidence at the time, not a permanent verdict.
Related terms
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