How to Create Fire Investigation Reports: 2024

Randy Elmore
July 5, 2024

Creating fire investigation reports is a critical task that requires scrupulous attention to detail and a systematic approach. Our goal here is to walk you through each section of a full-scale, in-depth, fire investigation report. Understanding each of the elements involved throughout these reports and how to assess them effectively is of great importance. Once you understand these components, your team can generate accurate and detailed reports that meet legal and insurance requirements, as well as improve the overall safety and efficiency of a fire investigation.

In this post, we'll take you through the particulars so you can be ready to conduct a fire investigation and document it thoroughly. Let's begin.

What's Included in a Fire Investigation Report

Fire investigation reports are structured in such a way by design that's to ensure each and every aspect of the incident is carefully documented and analyzed. Here's a breakdown of what that looks like in a fire investigation report:

  1. Receipt of Assignment: Documents who cases are assigned to and when a case was made.
  2. Incident Synopsis: Includes a summary of what happened, where, and when.
  3. Safety Assessment: Presence of potential hazards is identified and documented.
  4. Weather Information: Environmental conditions such as temperature, wind, and precipitation are documented.
  5. Structure Details: Structural details like the construction, layout, and any modifications that might impact the spread of the fire. 
  6. Photograph / Video Surveillance: Captures the scene's state before and after the fire.
  7. Utilities: Did gas, electricity, or water utilities play a role in the fire?
  8. Exterior Examination: Documenting damage to the building's outer structure and surrounding area.
  9. Building Systems: Documents the status of critical building systems (HVAC, electrical, plumbing).
  10. Interior Examination: Examining the condition of rooms and materials inside the building.
  11. Area(s) of Fire Origin: Pinpoints where the fire originated.
  12. Delayering / Reconstruction: Peels back layers to uncover hidden details about the fire's progression.
  13. Heat/Ignition and Fuel Sources Identified/Confirmed in Area of Origin: Sources such as appliances or electrical outlets.
  14. Point(s) of Fire Origin: Specifies the exact point where the fire started.
  15. Evidence Collected: Details all evidence collected from the scene and labs used for analysis.
  16. Ignition Sequence/Hypothesis Development and Tested: Outlines the developed hypotheses and ignition sequence, using the scientific method to test and validate these theories.
  17. Dollar Loss Estimate: Gives estimates for structural, vehicle, and content losses.
  18. Fire Cause Classification: Classifies the fire as incendiary, accidental, natural, or undetermined, based on the findings.              
  19. Definitions: Mentions any relevant definitions from the NFPA 921 standard, for consistency and clarity.

Creating Fire Investigation Reports with Blaze Stack

To thoroughly conduct an investigative report for fire, it's essential to have arson investigation tools like Blazestack at your disposal. With Blazestack, investigators have the advantage of advanced features that add to overall efficiency and accuracy in documenting fire scenes.

Blazestack has its own edge. Here's some its unique advantages:

  • Structured Workflow: Generates a structured workflow automatically based on the type of case, so all the necessary steps are followed.
  • Time Efficiency: It significantly reduces the time required to write reports. Completion takes minutes, rather than days.
  • Centralized Data: Consolidates all case notes, photos, documents, and media in one easy-to-access location.
  • Customization: Data fields and workflows are fully customizable to fit specific needs and unique investigation scenarios.
  • Accessibility: Fully accessible via smartphones, tablets, laptops, and desktops, so investigators can work on the go, anywhere.
  • Enhanced Data Collection: Data collection quality improved through guided prompts, pull-down menus, and predefined options.
  • Collaboration: Multiple investigators to collaborate on a single case, so they can work as a team and share insights.
  • Industry Standards: Incorporates NFPA 921 definitions and a 1033 checklist, helping investigators adhere to industry standards and best practices.
Using software like Blazestack gives arson investigators the edge they need to thoroughly streamline their team's fire investigation reports.

With Blazestack, creating fire investigation reports is easy. No matter the location, your team will be at-the-ready with features like these.

How to Write a Fire Investigation Report: Step-by-Step

For a comprehensive report on fire incidents, it's crucial to include the specific elements necessary for the fire investigation. This information ensures a detailed and accurate account of the incident. Be sure to include key details such as a synopsis, cause and origin, crime scene sketches, interview and interrogation findings, and data for insurance purposes. In the following sections, we'll go over these elements of fire investigation reports, so that they'll meet the necessary standards and provide a thorough record of the incident.

1. Receipt of Assignment

This is where you establish a clear starting point for the investigation. Accurate and detailed information here is going to set the stage for NFIRS data and the entire investigative process. Here's where documentation counts:

  • Date and Time of Incident: record the exact date and time the incident occurred. Use official dispatch records for accuracy.
  • Investigation Date and Time: Note when the investigation started. This can be found in the investigation log.
  • Responding Investigators: List number and names of all responding investigators; refer to team rosters and assignment sheets.
  • Incident Address: An exact location, including city and state/province, with a unit number, checking against official address databases.
  • Task Force Deployment: Indicate whether this was a task force deployment. Confirm from the dispatch records.

Best Practices:

Make sure the times are recorded in the same time zone.

Verify investigator names with official records to avoid misspellings.

2. Incident Synopsis

The incident synopsis is another crucial piece of fire investigation reports. It gives an overview of the incident, in summary, with key details that give context to the investigation. Document these things:

  • Citation/Arrest Information: Document if any citations or arrests were made. Obtain this from law enforcement reports.
  • Incident Type: Specify if it was a business or apartment complex fire and provide the name. Use property records for verification.
  • Alarm Type and Fire Type: Include the type of alarm and fire. This can be found in fire department incident reports.
  • Responding Fire Department: Name the fire department involved. Confirm from dispatch records.
  • Injuries/Fatalities: Record any injuries or fatalities, specifying between firefighters and civilians. Use medical and fire department reports.

Best Practices:

Be concise but thorough in the incident description.

Cross-check injury and fatality numbers with hospital records for accuracy.

3. Safety Assessment

In a fire investigation report, you must include a safety assessment. This identifies and documents potential hazards present at the scene. This is done to keep the investigation team and others involved safe throughout the investigation. Here's what you must document:

  • Hazards Present: Identify potential hazards such as air quality, collapse hazards, and general fire scene dangers. Conduct a site survey and consult hazard assessment guidelines.
  • PPE to Be Worn: Detail the required personal protective equipment (PPE). Refer to safety protocols and guidelines.

Best Practices:

Conduct a thorough on-site hazard assessment before documentation.

Check for PPE requirements and whether they meet industry standards.

4. Weather Information

For fire reports, weather information is another important piece of the puzzle. It helps investigators understand environmental conditions that could have influenced the fire. Here's the need-to-know:

  • Weather Source: Identify sources from which weather information comes. Consider using trusted sources such as the Weather Service.
  • Weather Conditions: Include temperature, humidity, wind direction, and speed. Obtain this data from official weather reports.

Best Practices:

Record weather data at multiple intervals if the investigation spans several hours.

Record any unusual weather or other environmental factors that have the potential to impact any investigation.

5. Structure Details

In accordance with the National Fire Incident Reporting System (NFIRS), structural details are vital. A fire investigator must document the details of the structure, including:

  • Occupancy Type: Describe the type of occupancy and construction. Use property records and blueprints.
  • Dimensions: Provide the length, width, and estimated square footage of the structure. Measure on-site and verify with building plans.
  • Foundation and Roofing: Describe the kind of foundation, roofing, and details of the building process.

Best Practices:

All structural details shall be checked with building permits and blueprints.

Use precise measuring tools.

For structural details in fire investigation reports, always cross check via blue prints and building permits.

Describe the Exposure

For fire investigation reports, you must describe the internal and external exposures. This helps to better understand how the fire spread. Here's what to document:

  • Internal Exposures: Describe how a fire could spread throughout the building via natural avenues including hidden spaces, stairways, chutes and shafts. Note the protective measures for interior areas, including firewalls, protection for valuable equipment and records.              
  • External Exposures:Determine other buildings or properties that may be exposed to the fire. Provide distances to exposures and other descriptions about them. If a vehicle is involved in the incident, include the VIN, license plate, make, model, and insurance information. 

Best Practices:

If there's a vehicle involved, cross-check vehicle details with DMV records. 

Be sure to take pictures of the vehicle at many different angles for documentation purposes.

6. Photography/Video Surveillance 

Photography and video surveillance is key in fire investigations. They provide visual documentation of the scene and are used in fire investigation reports. Here's what will be documented:

  • Photography: Record photographers' names and roles with reference to team rosters. State the type and number of photos taken with reference to a photographic log.
  • Video Surveillance: Record all locations and status of the surveillance cameras, then check the on-site surveillance systems.

Best Practices:

Ensure all photographs are time-stamped.

Use high-resolution cameras for clear documentation.

7. Utilities

In fire investigation reports, the utilities portion helps assess the status and role of things like electricity, gas, and water to determine their impact on the fire. Here's what would be documented:

Electrical Main

  • Service Details: Whether electrical service to the house had been installed and whether it was energized. Verify using utility company records.
  • Condition of Breaker Panel: State the condition of the breaker panel along with the type of wiring present.

Electrical Subpanel

  • Subpanel Condition: Document the condition and location of the subpanel.


  • Gas Service Details: Describe both the status of the gas service and the condition of the gas meter. Obtain information from the gas company.


  • Water Service: Record the status of the water service. Be sure to verify this with the water utility company.

Best Practices:

Inspect utilities using lockout/tagout procedures to safeguard the work.

Photograph utility panels and meters for visual records.

8. Exterior Examination

In fire investigation reports, the exterior examination analyzes the impact to the exterior and helps establish the fire's behavior and spread. Here's what we'll be included in the fire report:

  • Direction of Examination and Condition of Each Side: Describe the direction of examination and the condition of each side of the structure and the roof, using methods of systematic observation.
  • Condition of the Roof: Based on observation, describe general conditions that exist on the roof, including collapse, charring, or fire behavior influenced by firefighting activities.
  • Progression of Fire: Describe the progression of the fire across the roof. Be sure to note any areas of intense heat and any structural failures. Detail specific damage types and locations to support fire origin and cause hypotheses.

Best Practices:

Conduct the examination in a clockwise or counterclockwise direction for consistency.

Use a checklist to make sure that no area on the exterior has been left unchecked.

Be sure to include observations of burn patterns, heat exposure indicators, and structural damage correlations.

In the exterior examination of your fire investigation report, be sure to look at the condition of the roof and describe the progression of the fire.

9. Building Systems

The purpose of documenting building systems such as alarm systems & smoke alarms is to gain insight into their role and condition during the fire. Here's what you'll need to record:

Alarm System

  • Alarm System Status: Identify whether the alarm system had been fitted and was working by checking alarm systems records.
  • Alarm Type: Specify whether an alarm was given or not, and the status of the alarm at the time of the incident.

Smoke Alarms

  • Smoke Alarm Details: The status, location and whether they functioned to alert during the fire shall be included. Be sure to verify against maintenance records.

Best Practices:

Test alarm systems, if safe to do so.

Document the last date of alarm maintenance.

10. Interior Examination

For fire investigation reports, it's important to assess the internal damage, as it also helps in determining the fire's impact and spread. Here's what you'll need to detail in your fire report:

  • Condition of the Interior: Conduct a room-by-room survey and record the condition of the interior as well as any areas of interest or damage.
  • Damage Assessment: Identify and detail any areas with minimal damages as well as those with significant damages. Examples of this could be bathrooms, kitchens, or bedrooms.
  • Condition of Windows: Be sure to check the condition of windows in all areas. Note those that are broken or intact, which can indicate the fire's progression or attempts at ventilation. 
  • Contributing Items: Document items found that could have played a role in the fire. This could include things such as smoking materials or electrical devices.

Best Practices:

Each room needs to be documented in a consistent format.

Look for patterns that indicate fire spread or origin.

11. Area(s) of Fire Origin

Within all fire investigation reports, you're going to need to include a cause and origin report. It's crucial to determine how and where the fire started. Here's what will need to be documented:

  • Identify the Area: Identify just where the fire started using burn patterns and other indicators. Be sure to detail the fire's development stage at the time of discovery.
  • Status of Smoke Alarms: You'll record the presence and status of any smoke alarms in each area. You'll also indicate whether or not they were working and if they alerted the occupants.
  • Analyze Fire Development: Determine just how the fire developed and progressed over time. You'll record the status and performance of smoke alarms to evaluate compliance with fire safety regulations.

Best Practices:

Cross-reference with witness statements.

Use thermal imaging cameras to detect any hidden hot spots.

12. Delayering/Reconstruction

For reporting fires and investigating, delayering is going to aid in uncovering any hidden details that could reveal vital information about the fire. Here's what would be documented:

  • Delayering Process:Think of this process as a way of peeling back layers. You'll document the delayering process and any reconstruction efforts by using systematic de-layering techniques.

Best Practices:

Take photographs at each reconstructed stage.

Keep detailed notes of the reconstruction sequence.

13. Heat/Ignition and Fuel Sources Identified/Confirmed in Area of Origin

For a fire report, you'll need to identify and confirm any heat or ignition sources in the area of origin. Here's what you'll need to detail: 

  • Indicate the Source: Look for appliances, electrical outlets, etc. and record them.

Best Practices:

The elimination method should be applied to rule out the sources one by one.

Document all findings with photographs and notes.

14. Point(s) of Fire Origin

In fire investigation reports, the point(s) of origin is going to be the exact point where the fire started. For documentation purposes, this is what you'll need to keep in mind:

  • Look for Evidence: Things such as the most intense burn patterns, V-shaped marks, and areas of intense charring.
  • Evidence of Multiple Starting Points: If you find more than one ignition point for the fire, this can point to a deliberate ignition.
  • Evidence of Tampering of Manipulation: Be sure to take note of evidence of any heat source that was tampered with or intentionally set up to start a fire. This could include things such as cut wires, disabled safety features, or manipulated controls.

From the point(s) of origin, you'll analyze the spread of heat and smoke. It's important to remember that looking at the type and extent of damage to materials and structures can give vital clues about the intensity and duration of the fire. Be sure to document:

  • First Material Ignited: Watch for signs that accelerants may have been used, such as unusual burn patterns or rapid fire spread, and the appearance of residues that could be indicative of the presence of flammables.

Best Practices:

Note any melted, charred, or otherwise distorted materials that indicate high heat.

If necessary, validate findings with laboratory analysis.

Back up conclusions with multiple sources of evidence.

15. Evidence Collected 

Fire investigation procedure and techniques for NFIRS data require that evidence be documented and collected so that the labs can use it for analysis. Here's what will be included in fire investigation reports for different types of evidence:

Physical Evidence:

  • Debris Samples: These include charred materials, ashes, and residues from the fire scene.
  • Electrical Components: Gather wiring, circuit breakers, and electronic devices that may have contributed to the fire.
  • Ignition Sources: This includes any heat producing equipment found at the scene (lighters, matches).

Chemical Evidence:

  • Accelerant Samples: Soil, carpet, or other material thought to contain flammable liquids or accelerants.
  • Residue Analysis: This entails the collection of residues from the surfaces to determine the presence of accelerants or chemicals.

Documentary Evidence:

  • Photographs and Videos: The scene of the fire is documented through photographs and videos, after processing of the scene, to show damage patterns, point of origin, and areas of interest.
  • Witness Statements: Statements are obtained from all witnesses, including firefighters and first responders about what was observed and the actions performed.

Biological Evidence:

  • Human Remains: When there's loss of life, human remains can be collected and identified and the cause of death determined.
  • DNA Samples: DNA is collected from personal items or remains for identification purposes. 

Best Practices:

Check the evidence collection logs for consistency and accuracy.

16. Ignition Sequence/Hypothesis Development and Tested

With all fire investigation reports, you must outline the developed hypotheses and ignition sequence. Remember to use the scientific method and follow these guidelines for proper documentation:

  • Ask the Question: Is it an accidental, natural, or intentional ignition? 

Then, you'll support it with the most probable ignition sequence that cannot be disproved based on evidence collected:

  • Accidental: Evidence such as electrical burn marks, failed components, or witness statements corroborating that it was an accident.
  • System Failure: Physical evidence of system malfunction. This could be things such as broken parts, burned wires, or defective ports.
  • Arson: Presence of accelerants, unusual burn patterns, or security footage showing any suspicious activity.

Best Practices:

Test hypotheses against known facts.

Document the rationale behind each hypothesis.

17. Dollar Loss Estimate

Fire investigation reports will include a dollar loss estimate. These are estimates of structural, vehicle, and content losses. This fire damage assessment data is important to collect for insurance claims. Here's the need-to-knows:

How to Figure Out this Estimate

  • In order to get an estimate, you'll start by conducting a visual inspection of the fire scene. This is where you'll assess the extent of the damage. 
  • Documentation will be made via photographs and videos for the visual record.
  • Measurements and dimensions of the damaged areas and items must be recorded in the reports.
  • Be sure to take a look at property records. This will include the purchase price and any previous appraisals in order to get a clear baseline on the value.
  • Additionally, look at recent sales of similar properties, vehicles, and items to get an idea of current market values.

For Unknown or Unseen Items

  • Estimates for the unknown structures work a bit differently. The value of these items will be estimated on the structure's square footage and average cost per square foot in the area. 
  • For unknown items, estimate the current value of older items by calculating their depreciation from the original purchase price. 
  • Be sure to collect an inventory of items present before the fire to help estimate losses.
  • Statements will be collected from the property owner about the presence and value of items not visible after the fire.

To figure out this estimate, cost will be calculated to replace the structure with a new one of similar size and quality.

When filling out fire investigation reports, you must accurately classify the fire as incendiary, accidental, natural, or undetermined.

18. Fire Cause Classification

When it comes to fire cause and analysis, accurate classification is key. Remember to document the fire as:

  • Incendiary: A fire that's set deliberately.
  • Accidental: A fire that's not deliberate and results from unforeseen circumstances.
  • Natural: These are fires that are unplanned and caused by natural occurrences that don't involve humans. These happen in areas like forests, grasslands, or prairies.
  • Undetermined: A fire that lacks enough information to properly classify the fire.

19. Definitions

Definitions must be included in all fire investigation reports. The purpose of these definitions from the NFPA 921 standard is to communicate the most vital information to all persons dealing with the fire report. This could include a client, supervisor, prosecuting attorney, or other people interested in the report. Additionally, these definitions are going to help maintain consistency and clarity in the report.

Fire Dynamics and Behavior

It's vital for fire investigations and for the purpose of fire reports to understand fire dynamics and behavior. Here's some key concepts to keep in mind:

  • Combustion: The chemical process of burning, producing heat and light.
  • Flameover: Ignition of combustible gasses in the hot gas layer at the top of a compartment.
  • Flashover: Near-simultaneous ignition of most directly exposed combustible material in an enclosed area.
  • Backdraft: Rapid combustion or explosion caused by the introduction of oxygen into an oxygen-depleted environment containing combustible gasses.
  • Ceiling Jet: Horizontal flow of hot gasses that develop under a ceiling during a fire.
  • Radiant Heat: Heat transferred through electromagnetic waves without direct contact.
  • Conduction: Heat transfer through a solid material from a high-temperature region to a lower-temperature region.
  • Convection: Heat transfer due to the movement of fluids (liquids or gasses)
  • Creep: Slow, progressive spread of fire through materials.
  • Drop Down: Burning materials falling from higher levels to lower levels, potentially spreading the fire.
  • Fire Patterns: Visible or measurable physical effects that remain after a fire, which indicate the movement, intensity, and duration of the fire.
  • Smoke: Visible products of incomplete combustion, consisting of particles and gasses.
  • Soot: Black carbonaceous residue produced by incomplete combustion.

Fire Cause and Ignition

Determining the cause of the fire as well as the ignition source is key to an investigation and will always be included in fire reports, as discussed above. Key terms to remember include:

  • Fire Cause: Circumstances, conditions, or agency that brings together a heat source and fuel resulting in a fire.
  • Ignitable Liquid: Any liquid with a flash point below 100°F (37.8°C).
  • Ignition Temperature: Minimum temperature at which a material ignites and sustains combustion.
  • Competent Ignition Source: Ignition source capable of generating enough heat to ignite a specific fuel.
  • Spontaneous Heating: Self-heating of materials due to internal chemical reactions.
  • Spontaneous Ignition: Ignition of a material without an external flame or spark, usually due to spontaneous heating.
  • Autoignition: Ignition of a material without an external flame or spark due to temperature and conditions.
  • Electric Spark: Discharge of electricity through the air that can ignite flammable materials.
  • Arson: Criminal act of deliberately setting fire to property.

Fire Investigation Methods and Evidence

Systematic methods and collection of evidence are what drive an effective fire investigation. For fire investigation reports, here's where it counts:

  • Scientific Method: Systematic approach to investigation involving observation, hypothesis, experimentation, and conclusion.
  • Systematic Approach: Methodical process for conducting fire investigations.

Fire Origin and Progression

Determination of origin and spread is important in understanding how the fire was initiated and developed:

  • Point of Origin: Specific location where the fire started.
  • Area of Origin: General location where the fire started, encompassing the point of origin.
  • First Fuel Ignited: Initial material ignited by the heat source that starts the fire.
  • Arcing Through Char: Electrical arcing through a charred path, which can occur during or after a fire.
  • Mass Loss: Reduction in the mass of a material due to combustion.
  • Char: Carbonaceous residue remaining after incomplete combustion.
  • Clean Burn: Areas where the fire burned so intensely that all combustible materials are consumed, leaving a clean surface.

Building and Material Considerations

When a building is involved in a fire, a fire investigator must understand the materials and construction of the buildings involved. Here's what to take into account:

  • Fuel Load: Total quantity of combustible contents within a space or building.
  • Thermoplastic: Materials that become soft when heated and harden upon cooling.
  • Calcination of Gypsum: Chemical change in gypsum caused by exposure to heat, leading to dehydration and a powdery texture.
  • Bead: Small, round globules of glass or metal formed by intense heat, often seen in electrical fires.
  • Bonding: Permanent joining of metallic parts to form an electrically conductive path.
  • Poor Connections: Faulty or loose electrical connections that can generate heat and ignite materials.

Fire Safety and Prevention

Additionally, there's some key concepts for fire investigators to remember when it comes to safety on the scene:

  • Ventilation: Movement of air into and out of a structure, which can influence fire behavior.
  • Failure: Breakdown of a system or component leading to malfunction, which can contribute to fire causes.
  • Cause: The reason for the fire, which encompasses the ignition source, first fuel ignited, and circumstances leading to ignition.

Types of Fire Investigation Reports

Depending on the purpose of the fire reports, their type can vary. An example of this would be a fire department report for arson investigation training. Here's the main types of fire investigation reports:

NFIRS Reports

NFIRS, which stands for the National Fire Incident Reporting System, is a database that collects reports from fire departments all across the US. It includes comprehensive data that details the fire causes, property damage, injuries, and fatalities.

Municipal Fire Investigation Reports

These reports are prepared by municipal authorities or local fire departments. They document and investigate fire incidents that happen within their jurisdiction.

Private Fire Investigation Reports

These are reports prepared by private fire investigators usually hired by the insurance company, law firms, or other private entities to investigate fires. These reports are vital for recovery through insurance claims and prosecution of the offenders in the courts of law and fixing liability. Unlike the municipal or public fire investigation reports, due to reasons of unbiased and thorough analysis, such private fire investigation reports are conducted independently—oftentimes aided by forensic techniques and expertise in various disciplines.

Final Thoughts

All fire investigation reports have a structure that is meticulous by design. This, of course, is to ensure that each and every aspect of the fire incident is thoroughly documented and analyzed. 

Using Blazestack to create fire reports can greatly enhance the quality and effectiveness of all fire investigations. Through complete documentation and analysis, we can work together to uncover the truth behind every fire and make advancements in the field of fire investigation.

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