A fire investigation works out where a fire started and what caused it, using a structured, scientific method. Several parties may investigate the same fire for different reasons: the fire service, police, insurers and engineers acting for owners or other parties. For owners, the most important steps come early, by protecting the scene and evidence until the investigators have done their work.
Who investigates and why
| Party | Main interest |
|---|---|
| Fire department or fire marshal | Determining origin and cause under provincial fire safety law, identifying public safety issues and recording fire statistics |
| Police | Involved where a fire may be criminal, or where there is a death or serious injury |
| Insurers and their adjusters | Understanding the cause to handle the claim and look at whether someone else may be responsible |
| Engineers and private investigators | Acting for owners, insurers, manufacturers or other parties to examine equipment, systems and building factors |
| Workplace safety regulators | Involved where workers were injured or work activity may have played a part |
The fire authority's powers and responsibilities are set by provincial law and differ between Alberta, BC and Ontario. Public authorities have control of the scene at first; private investigators work around that and with permission.
The method
Professional fire investigation in North America generally follows NFPA 921, Guide for Fire and Explosion Investigations, which applies the scientific method to fire scenes. In practice that means:
- Recognize the need and define the problem: a fire happened and its origin and cause need to be found.
- Collect data: scene examination, photographs, measurements, witness interviews, building records, alarm and monitoring data, video and weather.
- Analyze the data using fire science and engineering knowledge.
- Develop hypotheses about the origin and cause that fit the data.
- Test the hypotheses against all the evidence, and rule out alternatives that do not fit.
- Select a final hypothesis only when it has been tested and holds up. Where that cannot be done, the cause should be reported as undetermined.
A good investigation does not start with a conclusion and look for evidence to support it. "Undetermined" is an honest and sometimes correct outcome.
Origin, cause and responsibility
- Origin is where the fire started, worked out from burn patterns, fire spread, witness accounts, alarm data and other evidence.
- Cause is the combination of a fuel, an ignition source and the circumstances that brought them together, such as an electrical fault, cooking, hot work, smoking materials or equipment failure.
- Responsibility is a further question about who, if anyone, is at fault. It is often the focus of insurance and legal processes and may involve more than one party.
Investigations often also look at why the fire spread as it did and how fire protection systems performed: whether alarms sounded, sprinklers operated and fire separations held.
What owners should do after a fire
Protect the scene. Do not clean up, move debris, remove equipment or start repairs until the fire authority has released the scene and your insurer agrees. Evidence that is lost or altered cannot be recovered, and disturbing it can affect claims and legal rights.
- Make sure the scene is secured against entry, weather and further damage, as directed by the fire department
- Notify your insurer promptly
- Do not enter the damaged area until it has been declared safe; fire-damaged structures and atmospheres can be hazardous
- Preserve records: maintenance logs, alarm panel history, monitoring company records, security video, work orders and contractor lists
- Write down what you and your staff saw, heard and did, while memories are fresh
- Keep failed equipment and suspected items in place, or have them collected and stored properly with a record of who handled them
- Tell other parties who may have an interest, such as equipment manufacturers, contractors and tenants, through your insurer or lawyer, so they can take part in examinations
Evidence and examinations
Where equipment such as an appliance, electrical panel or heater may be involved, investigators may remove it for a laboratory examination. Good practice is to give all interested parties notice and a chance to attend before items are taken apart or tested, so the results are not disputed later. Investigators keep a chain of custody record for each item.
What the findings are used for
- Insurance claim decisions and recovery from responsible parties
- Repairs and design changes to stop it happening again
- Improvements to maintenance, hot work controls and housekeeping
- Product recalls where a design defect is found
- Legal proceedings, where an investigator may give evidence
Many fires trace back to maintenance and housekeeping issues. See hot work permits and infrared thermography for electrical systems for two common prevention measures, and incident investigation for workplace follow-up.
How ehZee can help
Our fire investigations service looks at the building systems and equipment involved in a fire, working alongside the fire authority, insurers and other investigators. We report our findings and their basis in plain terms, and can recommend changes to reduce the chance of a repeat.
Common questions
How long before we can start repairs?
Not until the fire authority releases the scene and your insurer agrees that investigators no longer need it. This can take days or longer for complex fires. Temporary protection against weather and entry can usually be done sooner with permission.
Why would we hire our own investigator?
The fire department's findings may be brief, and other parties' investigators act for their own clients. An independent engineering investigation can examine building systems in more depth and protect your interests.