Search Results


Recommended Practice for the Classification of Combustible Dusts and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas

This recommended practice presents criteria to determine ignitability hazards in chemical process areas where combustible dusts are produced, processed, or handled to assist in the selection of electrical systems and equipment for safe use in Class II hazardous (classified) locations.

Choose Edition:

Select the Free Access Edition:


Current & Prior Editions

Choose Edition:

Select Edition

Next Edition

Technical Committee

Ask a Technical Question

NFPA members and public sector officials may submit a question on an NFPA code or standard. Responses are provided by NFPA Technical Staff on an informal basis.

NFPA 499: News

View Purchase Options

Related Products