2017 NFPA 499 Recommended Practice - Current Edition
When you select a digital product (pdf or digital access), you are purchasing a license to access NFPA Information electronically. To protect the authenticity of your product, certain restrictions apply.

NFPA Members save an additional 10%.

Item #: NFPA_499
Price: $0.00
Formats Available:

  • Description

    This Recommended Practice is a vital first step for the selection of electrical systems and equipment for safe use in Class II hazardous (classified) locations in accordance with the NEC®.

    Up-to-date with NFPA 70®: National Electrical Code®, the 2017 edition of NFPA 499: Classification of Combustible Dusts and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas presents criteria to determine ignitability hazards in chemical process areas where combustible dusts are produced, processed, or handled.

    Make sure you can properly select and install electrical systems and equipment for safe use in Class II hazardous (classified) locations.

    Filled with detailed guidelines and diagrams, NFPA 499 also provides extensive data on physical properties of selected combustible dusts, including specific Class II, Division, and dust group information.

    The 2017 edition of NFPA 499 is revised for:

    • Greater consistency between the figures and text regarding a transitional classified location around doorways
    • Alignment with the 2017 edition of the NEC -- including addition of the zone classification system

    It's an important tool for anyone who performs hazardous (classified) area classification.

    NFPA 499 is used by 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; and loss prevention or safety engineers. Insurance professionals, enforcing officials, and owner/operators of industrial facilities also need to stay up-to-date with the latest edition. (Print, 40 pp., 2017)

  • Table of Contents (2017 Current Edition)

    NFPA® 499 Recommended Practice for the Classification of Combustible Dusts and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, 2017 Edition

    Chapter 1 Administration
    1.1 Scope.
    1.2 Purpose.
    1.3 Application.
    1.4 Relationship to NFPA Codes and Standards.
    Chapter 2 Referenced Publications
    2.1 General.
    2.2 NFPA Publications.
    2.3 Other Publications.
    2.4 References for Extracts in Recommendations Sections.
    Chapter 3 Definitions
    3.1 General.
    3.2 NFPA Official Definitions.
    3.3 General Definitions.
    Chapter 4 Combustible Dusts
    4.1 General.
    4.2 Combustible Dust Testing.
    4.3 Additional Potential Combustible Dust Hazards.
    4.4 Classification of Combustible Dusts.
    4.5 Hybrid Mixtures.
    4.6 Electrostatic Discharges.
    4.7 Ignition Criteria.
    Chapter 5 National Electrical Code (NEC) Criteria
    5.1 Classification of Class II Hazardous Locations and National Electrical Code (NEC) Criteria.
    5.2 Classification of Combustible Dusts.
    Chapter 6 Classification of Combustible Dust Locations
    6.1 General.
    6.2 Conditions Necessary for Ignition of Combustible Dust.
    6.3 Class II, Division 1 or Zone 20/Zone 21 Classified Locations.
    6.4 Combustible Dust, Class II, Division 2 or Zone 22, Classified Locations.
    6.5 Unclassified Locations.
    6.6 Procedure for Classifying Areas.
    6.7 Housekeeping.
    6.8 Extent of Hazardous (Classified) Locations.
    6.9 Discussion of Diagrams and Recommendations.
    6.10 Classification Diagrams.
  • NFPA Digital Products

    Licensed PDFs can be accessed immediately. Instructions can be found in your order confirmation.