1、NFPA921 Guide for Fire and Explosion Investigations 2014 Edition NFPA, 1 Batterymarch Park, Quincy, MA 02169-7471 An International Codes and Standards Organization 1/14ISBN: 978-145590850-9 (Print)ISBN: 978-145590862-2 (PDF)IMPORTANT NOTICES AND DISCLAIMERS CONCERNING NFPASTANDARDS NOTICE AND DISCLA
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29、t no cost at www.nfpa.org/freeaccess.Copyright 2013 National Fire Protection Association. All Rights Reserved.NFPA921Guide forFire and Explosion Investigations2014 EditionThis edition of NFPA 921, Guide for Fire and Explosion Investigations, was prepared by the Tech-nical Committee on Fire Investiga
30、tions. It was issued by the Standards Council on November 12,2013, with an effective date of December 2, 2013, and supersedes all previous editions.This edition of NFPA 921 was approved as an American National Standard on December 2,2013.Origin and Development of NFPA 921NFPA 921, Guide for Fire and
31、 Explosion Investigations, was developed by the Technical Com-mittee on Fire Investigations to assist in improving the fire investigation process and thequality of information on fires resulting from the investigative process. The guide is intendedfor use by both public sector employees who have sta
32、tutory responsibility for fire investigationand private sector persons conducting investigations for insurance companies or litigationpurposes. The goal of the committee is to provide guidance to investigators that is based onaccepted scientific principles or scientific research.The first edition of
33、 the document, issued by NFPA in 1992, focused largely on the determi-nation of origin and cause of fires and explosions involving structures. The 1995 edition ofthe document included revised chapters on the collection and handling of physical evidence,safety, and explosions. NFPA 907M, Manual for t
34、he Determination of Electrical Fire Causes, waswithdrawn as an individual document and was integrated with revisions into this document asa separate chapter. Elements of NFPA 907M that relate to other chapters of this documentwere relocated appropriately. New chapters dealing with the investigation
35、of motor vehiclefires, management of major investigations, incendiary fires, and appliances were added.The 1998 edition of the document included a new chapter on fuel gas systems in buildings andthe impact of fuel gases on fire and explosion investigations. The chapter on electricity and firewas rew
36、ritten to improve organization, clarify terminology, and add references. In the chapter onfire patterns, several sections were revised. Other revisions were made in the chapter on physicalevidence on the subject of preservation of the fire scene and of physical evidence. The edition alsoincluded new
37、 text regarding ignitible liquid detection canine/handler teams.The 2001 edition of this document included new chapters on building systems, fire-relatedhuman behavior, failure analysis and analytical tools, fire and explosion deaths and injuries,and wildfire investigations. An updated chapter on mo
38、tor vehicle fires was written. The docu-ment was organized to group chapters into subjects that made it more usable.The 2004 edition of this document included a revision of the document to comply with thenew Manual of Style for NFPA Technical Committee Documents, and a new chapter titled, “Analyz-in
39、g the Incident for Cause and Responsibility,” a rewrite of the chapter on Legal Consider-ations, and a revision of the chapter on Recording the Scene.The 2008 edition of this document included rewrites of Chapter 5, Basic Fire Science;Chapter 6, Fire Patterns; Chapter 17, Origin Determination; Chapt
40、er 25, Motor Vehicle Fires;and Chapter 27, Management of Complex Investigations. A new Chapter 28, Marine FireInvestigations, was added to the document.The 2011 edition of this document included important changes to Chapter 4, Basic Method-ology, which had a new section on Report Review Procedures.
41、Chapter 12, Safety, was revised toinclude chemical and contamination exposure to the fire investigator. Chapter 18, Fire CauseDetermination, was completely revised to be like Chapter 17, following the scientific method. Thiswas also where the committee discussed that it is improper to base a hypothe
42、sis on the absence ofany supportive evidence, also known as negative corpus. Chapter 21, Explosions, was completelyrevised with significantly more illustrations. Chapter 23, Fire and Explosion Deaths and Injuries,was completely rewritten. Chapter 25, Motor Vehicle Fires, was substantially expanded i
43、n sections9211NFPA and National Fire Protection Association are registered trademarks of the National Fire Protection Association, Quincy, Massachusetts 02169.addressing recreational vehicles and agricultural equipment. Chapter 26, Wildfire Investigations, was completely reorga-nized and rewritten w
44、ith more photographs and illustrations.The members of the NFPA Technical Committee on Fire Investigations dedicated the 2011 edition of NFPA 921 tothe memory of our dear friend, colleague, and long-time staff liaison Frank Florence (19432010). Frank passed awayon July 27, 2010, after a brief illness
45、. Frank served with the Salt Lake City Fire Department for 31 years before retiringas Fire Chief. After retiring from the fire service, Frank joined NFPA in the Public Fire Protection Division. Since the2001 edition of NFPA 921, Frank had served as our Staff Liaison. Frank was an invaluable resource
46、 to our committeeand a strong supporter of the fire investigation profession. He is dearly missed. Our thoughts and prayers continue togo out to his wife, Diane, and his sons, Robert and Randy.The 2014 edition is the first NFPA Code or Standard document to be published in color. The color photograph
47、sgreatly enhance the effectiveness of the document, and no chapter will exemplify this change more than the FirePatterns chapter. Now, the contrast and color changes are much more clearly visible. Also, there has been a lot ofdebate and discussion in the fire investigation community concerning “nega
48、tive corpus” since it was addressed in the2011 edition, and the committee has added information to better clarify the actual intent.A new chapter, Fire Protection Systems, is based on a mandate in NFPA 1033, Standard for Professional Qualificationsfor Fire Investigator, which includes fire protectio
49、n systems as one of the 16 knowledge topics that every fire investigatoris required to have a basic, up-to-date knowledge of. This chapter also addresses key components, operational andinstallation parameters, data gathering, and analysis of active fire protection systems.The Analyzing the Incident for Cause and Responsibility chapter has been divided into two chapters. The classifi-cation of fire causes is in one chapter and the responsibility discussion is now in a separate chapter. As a result of newresearch and testing on electrical arcing over the last few years, the commit
