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Use the latest criteria in the 2012 NFPA 497 to determine ignitability hazards so you can properly select electrical systems and equipment for safe use in Class I hazardous (classified) locations.

NFPA 497: Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas applies to locations where flammable gases or vapors, flammable liquids, or combustible liquids are processed or handled and where their release into the atmosphere could result in their ignition by electrical systems or equipment. It also provides information on specific flammable gases and vapors, flammable liquids and combustible liquids whose relevant combustion properties have been sufficiently identified to allow their classification into the groups established by NFPA 70®: National Electrical Code® for proper selection of electrical equipment in hazardous locations.

Update your knowledge to keep pace with major revisions in the 2012 edition, including:

• Approved amendments to physical and chemical property data for materials included in the document
• Added definition for unclassified locations
• Added guidance on the use of portable electronic products, such as watches, cell phones, indicating where their use is permitted in Division 2 locations
• Revised and expanded Annex B
• Updated reference standards and extracted text to the most current editions

Various edits and formatting changes were also made to improve usability and consistency with other documents. This document is an essential on-the-job tool for installers and maintainers of industrial equipment using electrical power that is to be located in or near areas where flammable or combustible liquids, or flammable gases or vapors are stored, handled or used; equipment manufacturers providing equipment suitable for use in such electrically classified areas; design engineers/consultants; loss prevention or safety engineers; insurance; enforcing officials; owner/operator of industrial facilities.