NFPA 921:2021

Chapter 1 Administration 1.1 Scope. 1.2 Purpose. 1.3 Application. 1.4 Units of Measure. 1.5 Measurement Uncertainty. Chapter 2 Referenced Publications 2.1 General. 2.2 NFPA Publications. 2.3 Other Publications. 2.4 References for Extracts in Advisory Sections. Chapter 3 Definitions 3.1 General. 3.2 NFPA Official Definitions. 3.3 General Definitions. 3.4 Canine Definitions. Chapter 4 Basic Methodology 4.1 Nature of Fire Investigations. 4.2 Systematic Approach. 4.3 Relating Fire Investigation to the Scientific Method. 4.4 Basic Method of a Fire Investigation. 4.5 Level of Certainty. 4.6 Review Procedure. 4.7 Reporting Procedure. Chapter 5 Basic Fire Science 5.1 Introduction. 5.2 Chemistry. 5.3 Products of Combustion. 5.4 Fluid Flows. 5.5 Heat Transfer. 5.6 Fuel Load, Fuel Packages, and Properties of Flames. 5.7 Ignition. 5.8 Flame Spread. 5.9 Fire Spread in a Compartment. 5.10 Compartment Fire Development. 5.11 Fire Spread Between Compartments. 5.12 Paths of Smoke Spread in Buildings. Chapter 6 Fire Effects and Fire Patterns 6.1 Introduction. 6.2 Observations. 6.3 Analysis of Observations. 6.4 Fire Pattern Analysis. Chapter 7 Building Systems 7.1 Introduction. 7.2 Features of Design, Construction, and Structural Elements in Evaluating Fire Development. 7.3 Types of Construction. 7.4 Construction Assemblies. 7.5 Construction Materials. 7.6 Impact of Passive Fire Protection Systems on Investigation. 7.7 Design and Installation Parameters of the System. 7.8 Documentation and Data Collection. 7.9 Analysis. 7.10 Heating Systems. Chapter 8 Active Fire Protection Systems 8.1 Introduction. 8.2 Documentation of Fire Protection Systems. 8.3 Fire Alarm Systems. 8.4 Water-Based Fire Suppression Systems. 9.9 Ignition by Electrical Energy. 9.10 Interpreting Damage to Electrical Systems. 9.11 Identification of Arc Melting of Electrical Conductors. 9.12 Static Electricity. 9.13 Lithium Ion Batteries. Chapter 10 Building Fuel Gas Systems 10.1 Introduction. 10.2 Fuel Gases. 10.3 Natural Gas Systems. 10.4 LP-Gas Systems. 10.5 Common Fuel Gas System Components. 10.6 Common Piping in Buildings. 10.7 Common Appliance and Equipment Requirements. 10.8 Common Fuel Gas Utilization Equipment. 10.9 Investigating Fuel Gas Systems Incidents. Chapter 11 Fire-Related Human Behavior 11.1 Introduction. 11.2 History of Research. 11.3 General Considerations of Human Responses to Fires. 11.4 Factors Related to Fire Initiation. 11.5 Youth Fire-Setting Behavior. 11.6 Incendiary Fires. 11.7 Human Factors Related to Fire Spread. 11.8 Recognition and Response to Fires. Chapter 12 Legal Considerations 12.1 Introduction. 12.2 Constitutional Considerations. 12.3 Legal Considerations During the Investigation. 12.4 Pretrial Legal Considerations. 12.5 Trials. Chapter 13 Safety 13.1 General. 13.2 General Fire Scene Safety. 13.3 Fire Scene Hazards. 13.4 Safety Plans. 13.5 Chemical and Contaminant Exposure. 13.6 Personal Protective Equipment (PPE). 13.7 Emergency Action Plans. 13.8 Post-Scene Safety Activities. 13.9 Safety in Off-Scene Investigation Activities. 13.10 Special Hazards. Chapter 14 Sources of Information 14.1 General. 14.2 Legal Considerations. 14.3 ASTM Standards for Collecting, Preserving, and Evaluating Data. 14.4 Forms of Information. 14.5 Sources of Non-Scene Data. 14.6 Private Sources of Information. Chapter 15 Planning the Investigation 15.1 Introduction. 15.2 Basic Incident Information. 15.3 Organizing the Investigation Functions. 15.4 Pre-Investigation Team Meeting. 15.5 Specialized Personnel and Technical Consultants. 15.6 Case Management. Chapter 16 Documentation of the Investigation 16.1 Introduction. 16.2 Photography. 16.3 Note Taking. 16.4 Diagrams and Drawings. 16.5 Reports. Chapter 17 Physical Evidence 17.1 General. 17.2 Physical Evidence. 17.3 Preservation of the Fire Scene and Physical Evidence. 17.4 Contamination of Physical Evidence. 17.5 Methods of Collection. 17.6 Evidence Containers. 17.7 Canine-Handler Teams Introduction. 17.8 Identification of Physical Evidence. 17.9 Transportation and Storage of Physical Evidence. 17.10 Chain of Custody of Physical Evidence. 17.11 Examination and Testing of Physical Evidence. 17.12 Evidence Disposition. Chapter 18 Origin Determination 18.1 Introduction. 18.2 Overall Methodology. 18.3 Data Collection for Origin Determination. 18.4 Analyze the Data. 18.5 Developing Origin Hypotheses. 18.6 Testing an Origin Hypothesis for Validity. 18.7 Selecting the Final Hypothesis. 18.8 Origin Insufficiently Defined. Chapter 19 Fire Cause Determination 19.1 Introduction. 19.2 Overall Methodology. 19.3 Data Collection for Fire Cause Determination. 19.4 Analyze the Data. 19.5 Developing Cause Hypotheses. 19.6 Testing the Cause Hypothesis for Validity. 19.7 Selecting the Final Hypothesis. 19.8 Incident Classification. Chapter 20 Analyzing the Incident for Cause and Responsibility 20.1 General. 20.2 The Cause of the Fire or Explosion. 20.3 The Cause of Damage to Property Resulting from the Incident. 20.4 The Cause of Bodily Injury or Loss of Life. 20.5 Determining Responsibility. Chapter 21 Failure Analysis and Analytical Tools 21.1 Introduction. 21.2 Time Lines. 21.3 Systems Analysis. 21.4 Mathematical Modeling. 21.5 Fire Testing. 21.6 Data Required for Modeling and Testing. Chapter 22 Explosions 22.1 General. 22.2 Types of Explosions. 22.3 Characterization of Explosion Damage. 22.4 Effects of Explosions. 22.5 Factors Controlling Explosion Effects. 22.6 Seated Explosions. 22.7 Nonseated Explosions. 22.8 Gas/Vapor Combustion Explosions. 22.9 Dust Explosions. 22.10 Backdraft (Smoke Explosions). 22.11 Unconfined Vapor Cloud Explosions. 22.12 Explosives. 22.13 Investigation of Explosive Incidents. 22.14 Investigating the Explosion Scene. 22.15 Analyze Origin (Epicenter). 22.16 Analyze Fuel Source. 22.17 Analyze Ignition Source. 22.18 Analyze to Establish Cause. Chapter 23 Incendiary Fires 23.1 Introduction. 23.2 Incendiary Fire Indicators. 23.3 Potential Indicators Not Directly Related to Combustion. 23.4 Other Evidentiary Factors. Chapter 24 Fire and Explosion Deaths and Injuries 24.1 General. 24.2 Mechanisms of Death and Injury. 24.3 Consumption of the Body by Fire. 24.4 Postmortem Changes. 24.5 Investigating Fire Scenes with Fatalities. 25.1 Scope. 25.2 Appliance Scene Recording. 25.3 Origin Analysis Involving Appliances. 25.4 Cause Analysis Involving Appliances. 25.5 Appliance Components. 25.6 Common Residential Appliances. Chapter 26 Motor Vehicle Fires 26.1 Introduction. 26.2 Vehicle Investigation Safety. 26.3 Fuels in Vehicle Fires. 26.4 Ignition Sources. 26.5 System Identification and Function. 26.6 Body Systems. 26.7 Motor Vehicle Fire Scenes. 26.8 Motor Vehicle Examinations. 26.9 Total Burns. 26.10 Special Considerations for Incendiary Vehicle Fires. 26.11 Vehicle Ignition Components. 26.12 Vehicles in Structures. 26.13 Recreational Vehicles. 26.14 Heavy Equipment. 26.15 Agricultural Equipment and Implements Introduction. 26.16 Hybrid Vehicles. 26.17 Towing Considerations. 26.18 Hydrogen-Fueled Vehicles. Chapter 27 Wildfire Investigations 27.1 Introduction. 27.2 Wildfire Fuels. 27.3 Weather. 28.1 Scope. 28.2 Basic Information and Documents. 28.3 Communications Among Interested Parties. 28.4 Understandings and Agreements. 28.5 Management of the Investigation. 28.6 Evidence. 28.7 Logistics. 28.8 Site and Scene Safety. Chapter 29 Marine Fire Investigations 29.1 Introduction. 29.2 Powerboat and Sailboat Terminology. 29.3 Boat Investigation Safety. 29.4 System Identification and Function. 29.5 Exterior. 29.6 Interior. 29.7 Propulsion Systems. 29.8 Ignition Sources. 29.9 Documenting Boat Fire Scenes. 29.10 Boat Examination. 29.11 Boats in Structures. 29.12 Legal Considerations. Annex A Explanatory Material Annex B Bibliography Annex C Informational References Annex D Photograph Credits

This document is designed to assist individuals who are charged with the responsibility of investigating and analyzing fire and explosion incidents and rendering opinions as to the origin, cause, responsibility, or prevention of such incidents, and the damage and injuries which arise from such incidents.