How Do I determine if I need a room or building to be class 1 or 2 2

[ddrowe0217]

I need to determine if a building or room needs to be Class 1, Class 2 or if I can leave it as no classification and just maintain the electrical. The room contains powder from explosives that is wound into a cord. There is some dust but not an any noticable quantities. There are no chemical fumes. The only concern is the powder is an explosive. Should the room be Class 2 Div 1 or 2 just due to the nature of the chemical or are there tests I can do to prove that it does not have to have the Class 1 or Class 2 rating?

Thank you

 

[Logicon]

For a definition of the different CLASS locations...see this link.

http://www.osha.gov/doc/outreachtraining/htmlfiles/hazloc.html

OSHA does not tell you what to do. Assuming your location follows the NEC for installations in your location, that is your "requirement" handbook. Use the OSHA definition for the location to determine what class your room may be in. Be careful to pay attention to the vague definition...the key phrase being "MAY BE PRESENT". It doesn't matter how clean you might keep a room, if there is a chance of the hazard being present, then you had better classify the room to be legally safe.

Class will not be a deep enough definition of the location. You also need to identify the Group and Division per NEC. Scroll down on the OSHA link above for help with that.

Once your Class, Division, Group is defined, look to the NEC code in Articles 500-510 (generally) to find specific requirements related to your location.

Good Luck!


Marc Whitney

http://www.thelogicongroup.com

 

[rbalex]

If the "powder" is an explosive in its own right it is not subject to the NEC. See NEC Section 500.1 FPN No. 1

The rules are found in NFPA 495, Explosive Materials Code. You need a consultant that is familiar with the installation, the materials and the Explosive Materials Code. Often the facility's insurance carrier can direct you to such a person.