GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
(OP)
Analyzer Building, project what I started a some time ago, provides better ventilation system and reduction of classified area from Division 2 Group B to Division 2 Group D. Building is very old with some existing equipment as "general purpose equipment" ( lighting, fans) i.e. with unclassified equipment inside hazardous classified zone.
I have to STAMP this project as P.Eng. but I am refusing.
Please your comments !
I have to STAMP this project as P.Eng. but I am refusing.
Please your comments !






RE: GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
I think it is possible to go from Div 1 to Div 2 by means of ventilation.
RE: GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
RE: GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
RE: GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
Elecme
RE: GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
Study the entire NEC article 500 topics and related API topics regarding groups. You do not move from group B to D but the room might be overclassified unless there is lots of hydrogen. There are several things that you should consider. Move the sample systems and cylinders outside. Restrict the calibration and sample gas flow with excessive flow fittings from Swagelok. Pressureize the room with NFPA HVAC units that get air from outside the hazardous area. Minimize the group B content to permit classifying group D. Design and select the installation materials to otherwise comply with group B.
Obtain support from the analyzer manufacturers if necessary.
John
RE: GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
RE: GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
RE: GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
RE: GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
RE: GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
RE: GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
Suggest thorough review of NEC 500-501 and applicable sections of NFPA.
RE: GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
"I doesn't matter if it's group B or D. Unclassified equipment can't be in a Cl.2 area (except motors without arc producing contacts). I agree with dpc."
I don't agree. In general the NEC permits the use of nonclassifed equipment in Class 1 Division 1 areas as long as there are no arc producing contacts and the normal operating temperature of the equipment is 80% or less of the ignition temperature for the gasses involved. See 501.3(B).
Don
RE: GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
But I wonder if resqcapt has a typo in the last post. For a Class 1, Div 1 area, the NEC has some very specific requirements even for non-arcing devices such as meters, transformers, etc. Maybe you are referring to Class 1, **Div 2**, where NEC allows general purpose enclosures for non-arcing equipment.
What I actually said in my first post was that it is not possible to re-classify an area that would normally be Div 2 to unclassified by means of ventilation. It is possible to re-classify an area from Div 1 to Div 2 by means of ventilation.
This is how I recall it, but it has several years since I actually had to think about it, so I could certainly be mistaken.
RE: GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
Yes, I do have a typo in my previous post. It should read Class 1 Division 2, not Division 1. Sorry.
Don
RE: GENERAL PURPOSE EQUIPMENT IN HAZARDOUS AREA
Yes there are exceptions. I assumed the discussion pertained to equipment in the space that would be required to be explosionproof if the space is Div 2.