This edition of NFPA 496, Standard for Purged and Pressurized Enclosures for Electrical
Equipment, was prepared by the Technical Committee on Electrical Equipment in Chemical
Atmospheres and acted on by NFPA at its May Association Technical Meeting held May
18–21, 2003, in Dallas, TX. It was issued by the Standards Council on July 18, 2003, with
an effective date of August 7, 2003, and supersedes all previous editions.