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Use the latest criteria in the 2013 edition of NFPA 499 to determine electrical classification for combustible dust hazards so you can properly select and install electrical systems and equipment for safe use in Class II hazardous (classified) locations.

NFPA 499: Classification of Combustible Dusts and of Hazardous Locations for Electrical Installations in Chemical Process Areas contains detailed guidelines and diagrams that are useful tools for professionals who perform hazardous (classified) area classification as specified by NFPA 70: National Electrical Code for the purpose of selecting and installing electrical equipment that will not be an ignition source in environments where combustible dusts are produced, processed, or handled. This Recommended Practice also provides extensive data on physical properties of selected combustible dusts, including specific Class II, Division, and dust group information.

Major changes to the 2013 NFPA 499:

• Revised document scope clarifies the applicability of NFPA 499 to various forms or sources of combustible dusts.
• New chapter on combustible dusts addresses the various aspects of ignition for combustible dusts.
• Updated references correlate with current codes and standards.
• New references are applicable to various test methods for determining dust explosibility properties.

Additional changes in NFPA 499 improve usability and consistency with other documents.

The 2013 NFPA 499 is a valuable on-the-job tool for facility operators and installers and maintainers of industrial equipment using electrical power that is to be located in or near areas where combustible dusts are produced, used, or handled; equipment manufacturers providing equipment suitable for use in such electrically classified areas; design engineers/consultants; loss prevention or safety engineers; insurance professionals; enforcing officials; and owner/operators of industrial facilities.