There’s a new NFPA 496 2013 Edition, “Standard for Purged and Pressurized Enclosures for Electrical Equipment,” and it’s available now from Document Center Inc. The standard provides the user with the requirements for the design and operation of purged and pressurized electrical equipment enclosures.
The protection technique covered by NFPA 496: 2013 is used in Class I and Class II hazardous (classified) locations to reduce or prevent the presence of flammable materials within electrical equipment enclosures as specified by NFPA 70, the National Electrical Code. It also includes chapters covering protection of analyzers and rooms housing analyzers and a chapter on pressurized control rooms.
This new edition provides the following changes:
- Revisions to the definitions for Type X Pressurizing, Type Y Pressurizing, and Type Z Pressurizing clarify that pressurizing keeps a flammable atmosphere around a protected enclosure from entering an enclosure, which enables the use of either ignition-capable equipment (in Type X Pressurizing or Type Z Pressurizing) or Division 2 or Zone 2 equipment (Type Y Pressurizing) inside an enclosure.
- The addition of a new requirement affecting electrical alarm actuators in Type Y Pressurizing to require them to be identified for a Division 1 or Zone 1 location.
- Clarification of requirements affecting cutoff switch actuators in Type X Pressurizing.
All current NFPA standards are available from Document Center Inc. at our website, www.document-center.com. Or contact us by phone (650-591-7600), fax (650-591-7617) or email (info@document-center.com) in order to get more information about ordering, etc. We accept orders from U.S. companies using PO’s on a net 30 basis or with credit card payment. For all non-U.S. purchases, prepayment is required.
