Demolition Order During Origin Determination at a Strip Mall
At 06:10 a fire in a four-unit strip mall destroyed three units and heavily damaged the common attic. The fire investigator arrives at 08:00 and begins an exterior and interior examination. By 09:30 the investigator has narrowed the area of origin to the rear of Unit B but has not determined the cause. At 09:45 the building official posts the structure as unsafe and orders emergency demolition within eight hours because a masonry parapet is leaning toward the sidewalk. The property owner wants to remove business records and a safe; the insurance adjuster wants to move a charred delivery van; a tenant demands access to retrieve cash. The investigator has two technicians and one camera. The demolition contractor is already staging equipment. The investigator must decide how to use the limited window, what to document, what evidence to collect, and how to deal with the competing demands. No one has been injured.
1. How should the investigator prioritize the limited time before demolition?
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The investigator should treat the eight-hour window as a scene-processing deadline, not an invitation to cut corners. Priority order: secure the scene and stop unauthorized removal of contents; document the exterior and the origin area from the safest accessible points, including the parapet condition and the unit separation; complete the origin examination in Unit B, including the floor, ceiling, and electrical components; collect representative evidence and samples before demolition; interview the owner, tenant, and any witness about the van and business records; and photograph and diagram the scene before the contractor arrives. The investigator should not enter an unsafe structure; if the building official will not allow access, the investigator should request a limited escort or use exterior documentation and remote imaging. The cause may end up undetermined because of destruction, and the file must say so. NFPA 1033 JPRs require systematic scene examination, evidence preservation, and documentation-not a guess under time pressure.
2. How should the investigator handle the owner, insurer, tenant, and demolition contractor who want access?
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The investigator should explain that the scene is under investigation and that removing contents or the van can destroy evidence and undermine the chain of custody. If the investigator has legal authority as the AHJ's representative, he should deny access until documentation is complete; if not, he should ask the fire marshal or law enforcement to secure the scene. The owner's business records can be photographed and released only after they are documented; the safe should not be opened by the owner without documentation. The insurance adjuster can be given a written inventory and a schedule, not unsupervised access. The tenant's cash retrieval should wait until the area is documented and safe. All requests and denials should be logged. If the demolition contractor arrives early, the investigator should confirm the demolition order in writing and coordinate a stop-work period for documentation. This is the NFPA 1033 evidence-preservation and scene-security JPR in practice.
3. If the cause cannot be established before demolition, how should the report characterize the finding?
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The investigator should document the limits of the examination: the parapet hazard, the demolition deadline, and the areas that could not be examined safely. If the origin is supported but the cause cannot be determined, the report should classify the cause as 'undetermined' rather than 'accidental' or 'electrical.' NFPA 1033 requires the investigator to use a systematic methodology and to document the evidence, not to fill gaps with speculation. The report should list the hypotheses considered, the evidence for and against each, and the reason each could not be eliminated or confirmed. If samples are collected, the report should state where they were taken and the chain of custody. The investigator should recommend a supplemental examination if conditions change, and should note that demolition destroyed potential evidence. That protects the integrity of the investigation and gives the fact-finder an honest basis for the report.