Today is...
Friday, November 17, 2017
The Automation Safety Community Forum.
Pressurized Nema 4x Enclosure
Certification for a pressurized Nema 4x Enclosure for hazardous location

I know Nema 7 enclosure can be used for hazardous location, can we

1. used a pressurized Nema 4x location for hazardous environment?

2. if yes, can it be certified from a third party?

i learned somewhere, Pressurized Nema 4x enclosure can be used for hazardous environment but cannot be certified.

Not my are area but I did a quick glance at NFPA 496 Standard for Purged and Pressurized Enclosures for Electrical Equipment and there doesn't appear to be a requirement for any specific NEMA type enclosure.

http://www.nfpa.org/codes-and-standards/all-codes-and-standards/list-of-codes-and-standards/detail?code=496

Certified is something that needs definition, generally different depending on where you are in the world. North America has a set of standards, Europe has another. There are commonalities, but before wasting any more time on it you need to start with which standards and certifications you need.

But as a general statement, there are indeed companies that specialize in this and offer "certified" systems, both in North America and in other parts of the world.

USA:
https://www.pentairprotect.com/en/hoffman/purging-pressurization-systems

UK:
http://www.expoworldwide.com/resources/faq-purge-and-pressurization-explained/#