NFPA 499-2021 PDF Download

NFPA 499-2021 provides guidance and criteria for selecting and installing electrical systems and equipment in hazardous environments where combustible dusts are present. The standard aims to mitigate the ignition hazards associated with the presence of combustible dusts in industrial settings.

NFPA 499 is essential for individuals responsible for hazardous area classification, facility operators, installers, and maintainers of electrical equipment in the presence of combustible dusts. It is also valuable for owners or operators of industrial facilities, insurance professionals, authorities having jurisdiction (AHJs), enforcing officials, and manufacturers of equipment for electrically classified process areas. Design engineers/consultants and safety engineers can also benefit from this standard.

The 2021 edition of NFPA 499 has been revised to align with the NFPA 70®, National Electrical Code®, 2020 edition, and the latest practices in the chemical process industries. The standard provides detailed guidelines, classification diagrams, and dust group classifications for a wide range of combustible dusts.

Notable revisions in the 2021 edition include updated definitions for combustible fibers/flyings and the inclusion of a classification for portable electronic products (PEPs) in line with UL 121203. The document has also been edited to ensure consistency with the NEC® electrical classification in terms of area electrical classifications.