NFPA 921 Chapter 27 Overview

NFPA 921 Chapter 27: Fire Cause and Origin Analysis Overview

• Chapter 27 of NFPA 921 focuses on fire cause and origin investigations. A systematic approach, critical thinking, and thorough documentation are essential.
• This chapter provides a framework for the entire investigation, not specific methods.
• The goal is to link the ignition source to the fire's circumstances using clear reasoning and evidence.

Key Elements of Fire Cause and Origin Analysis

• Initial Observation and Site Safety: Assess scene safety and document hazards immediately.
• Establishing a Potential Fire Cause: Create a preliminary list of potential causes (e.g., equipment malfunction, unattended cooking) based on initial data.
• Evaluating Potential Causes: Analyze each potential cause against available evidence, prioritizing by probability.
• Gathering Evidence: Systematically collect and document physical evidence and witness statements.
• Fire Scene Reconstruction and Documentation: Document the fire scene using multiple angles and scale; be mindful of fire conditions.
• Using Data to Evaluate Options: Correlate fire evidence with potential causes.
• Formulating Conclusions: Use evidence, observations, and analysis to deduce the cause and origin, presenting findings objectively in a written report.

Important Considerations in the Analysis

• Prioritization and Selection of Potential Causes: Start with the most likely causes and move to less probable ones as evidence is assessed.
• Pattern Recognition: Use patterns like the fire's path or unusual marks to confirm or refute conclusions.
• Understanding the Importance of Evidence Limitations: Acknowledge and document any missing information or inconsistencies.
• Application of Scientific Principles to Evidence Evaluation: Use scientific knowledge (e.g., heat transfer, combustion).
• Review of Possible Explanations: Scrutinize all possible explanations.
• Examination of All Potential Evidence: Objectively examine all possible evidence.
• Elimination of Implausible Causes: Remove causes inconsistent with the evidence.
• Recognizing that multiple causes can contribute: Account for combined factors (e.g., equipment malfunction and environmental issues).
• Understanding Limitations, and Scope of Evidence: Be aware of the analysis's limitations regarding the scope of answerable questions.
• Objectivity and Objectiveness in Documentation: Thoroughly document findings with diagrams and photos; avoid bias.
• Review of Evidence from Multiple Perspectives: Consider diverse viewpoints to mitigate blind spots and enhance reliability.

Documentation and Reporting

• Record Keeping: Maintain detailed, accurate, and thorough records throughout the investigation.
• Reporting Procedures: Communicate findings, conclusions, and reasoning logically and concisely in the report.
• Presenting Findings Objectively: Present evidence-based, unbiased findings, addressing potential errors, missing evidence, and inconsistencies objectively.