Hazardous (Classified) Location Documents

[Safehawke]

I am presently involved with a project where a chemical processing room which has equipment processing ethanol needs to have what is referred to as an Electrical Classification Area Drawing prepared. I am assuming this is the same as the Hazardous (Classified) Location Documents referred to in the NEC Code as well as NFPA-497, and American Petroleum Institutes(API) RI-500 guideline. My question is who should be responsible for preparing this document a chemical process engineer or an electrical engineer. The purpose for this question is that the AHJ is requesting that this drawing be stamped by a registered professional engineer. Since NEC mandates this document be generated it would appear this drawing is viewed as a Electrical Drawing (ALA the title). The project lead is asking that a chemical engineer prepare and stamp this drawing. My concern is since it is viewed as an Electrical drawing, and I stamp it, will I be practicing outside my school of practice? Any help on this subject would be most helpful.

 

[rbalex]

Re: Hazardous (Classified) Location Documents

... My concern is since it is viewed as an Electrical drawing, and I stamp it, will I be practicing outside my school of practice? Any help on this subject would be most helpful.

This question is more legal than technical. The question you should be asking is, "Who, in your organization, is qualified to create the document?"

For locations classified by "Divisions,"the NEC does not require the documents to be prepared by a PE although many Jurisdictions do. For locations classified by "Zones" a PE is required. See 505.7(A). The branch of engineering is not specified however.

If either you or the Chemical Engineer are qualified to create the document, then either of you may seal it; subject to the Jurisdiction's documented requirements, of course. Most don't specify the branch of engineering. It is common for electrical engineers to prepare them.

Edit Add: BTW in most States the PE determines whether or not they are qualified to perform the work. There may be State or local restrictions though - you will need to check that out. But it is very unlikely electrical area classification documents have a particular branch identified. The fundamental rule is that the person who prepares the document should be the one to seal it.