ORIGIN and DEVELOPMENT of NFPA 921
NFPA 921, Guide for Fire and Explosion Investigations, was developed by the Technical Committee on Fire Investigations to assist in improving the fire investigation process and the quality of information on fires resulting from that process. The goal of the committee is to provide guidance to both public and private investigators based on accepted scientific principles and scientific research.
The first edition of the document, issued by NFPA in 1992, focused largely on the determination of the origin and cause of fires and explosions involving structures. The 1995 edition of the document included revised chapters on safety, explosions, and the collection and handling of physical evidence. NFPA 907M, Manual for the Determination of Electrical Fire Causes, was withdrawn as an individual document and integrated, with revisions, into NFPA 921.
The 1998 edition of the document included a new chapter on fuel gas systems in buildings and the impact of fuel gases on fire and explosion investigations. Revisions were made to the chapters on electricity and fire, fire patterns, and physical evidence. The 1998 edition also included new text regarding ignitable liquid detection canine/handler teams.
The 2001 edition of NFPA 921 was reorganized for usability and included new chapters on building systems, fire-related human behavior, failure analysis and analytical tools, fire and explosion deaths and injuries, and wildfire investigations. The 2004 edition included a revision of the document to comply with the new Manual of Style for NFPA Technical Committee Documents. A new chapter, "Analyzing the Incident for Cause and Responsibility," was included, and chapters relating to legal considerations and recording the scene were revised.
The 2008 edition included rewrites of Chapter 5, Basic Fire Science; Chapter 6, Fire Patterns; Chapter 17, Origin Determination; Chapter 25, Motor Vehicle Fires; and Chapter 27, Management of Complex Investigations. A new Chapter 28, Marine Fire Investigations, was added to the document.
The 2011 edition saw changes to Chapter 4, Basic Methodology, and a new section on Report Review Procedures. Chapter 12, Safety, was revised to include chemical and contamination exposure to the fire investigator. Chapter 18, Fire Cause Determination, was revised to mirror Chapter 17, following the scientific method. This edition also saw the introduction of the negative corpus and significant rewrites of Chapter 21, Explosions; Chapter 23, Fire and Explosion Deaths and Injuries; and Chapter 26, Wildfire Investigations. Chapter 25, Motor Vehicle Fires, was substantially expanded to further address recreational vehicles and agricultural equipment.
The 2014 edition was the first NFPA Standard to be published in color. The color photographs greatly enhance the effectiveness of the document and are especially beneficial in the chapter on Fire Patterns. In additional, the concept of negative corpus was further clarified with additional information. A new chapter, Fire Protection Systems, was added based on the 16 knowledge topics found in NFPA 1033, Standard for Professional Qualifications for Fire Investigator. The chapter Analyzing the Incident for Cause and Responsibility was divided into two chapters, and the committee added information and photographs that further illustrate concepts of electrical arcing.
The 2017 edition of NFPA 921 includes many updates to accurately reflect current practices, technologies, research, and concepts. Chapter 8, Fire Protection Systems, was renamed Active Fire Protection Systems since passive systems are addressed in Chapter 7, Building Systems. The changes to Chapter 16, Documentation of the Investigation, brings the document up to date with current technology in the area of digital photography and 3D scanning. The concept of the origin matrix was included in Chapter 18, Origin. That concept addresses the impact of ventilation on origin determination. One of the most important changes can be found in the scope of NFPA 921. Chapter 1 was revised to address the misapplication of reports from the National Fire Incident Report System (NFIRS) as Fire Investigation Reports.
[The above information was obtained from pages 921-1 & 921-2 of NFPA 921, 2017 edition.]
The covers of each edition of NFPA 921 are shown below. The contents of each edition are copyrighted by the National Fire Protection Association.
