Class 1 Div 2 ?

[Knick]

We have three open front spray booths. Two I have specs on and one I don't. The two I have specs on show a 3 foot radius that wraps from the inside to 3' back on the outside that is a Class 1 Div 2 rating. The booths all have lights that are on the outside of the booth and behind the Class 1 Div 2 Hazardous area. Now for the booth I have no specs we added two light on the outside but just fall inside the Class 1 Div 2 area (by other booths specs).

Now I had two contractors come in and give quotes on wiring the light for us and I am not sure which one is right with there quote. One wants to use pipe the other wants to use SO cord and run to a box outside of the Class 1 Div area and go to a normal 4 sq box and EMT from there. As you can imagine the one quote is double of the other. What is the best way for me to try and see what contractor is quoting this right?

Should I get a third contractor involved?
Should I just go with the lower quote?
Should this booth we have no spec on be treated as a Class 1 Div1?

Thank you

 

[rbalex]

First, it is an NEC requirement to have your electrical area classification properly documented. [Section 500.4(A)] The booth without such documentation is already in violation. You need someone qualified to produce the documentation (and probably the design).

Second, the contractor suggesting SO cord is not qualified. I don't know about the other contractor without knowing the full details of the proposed installation.

 

[Knick]

First, it is an NEC requirement to have your electrical area classification properly documented. [Section 500.4(A)] The booth without such documentation is already in violation. You need someone qualified to produce the documentation (and probably the design).

Second, the contractor suggesting SO cord is not qualified. I don't know about the other contractor without knowing the full details of the proposed installation.

Bob

Not knowing the manufacturer of booth is there someone else that can produce the documentation?
I kinda wondered on the SO cord but was not sure as I have seen talk about its use in Haz locations.

Thank you for your time
Knick

 

[rbalex]

Bob

Not knowing the manufacturer of booth is there someone else that can produce the documentation?
I kinda wondered on the SO cord but was not sure as I have seen talk about its use in Haz locations.

Thank you for your time
Knick

I usually recommend starting with you insurer. I'm always surprised when they don't get intimately involved with a classified facility.

If they aren't helpful, I'd contact a professional engineer. Fortunately, paint facilities can usually be classified directly from NEC Article 516. I would suggest using the 2014 Edition. It is detailed and well updated.

I would not suggest contacting your local building authorities until after the classification/design is complete.

 

[petersonra]

there are some cases where you can use hard service cord in at least some classified areas. I don't think SO cord is listed as hard service though.

without looking real close at the applicable code sections I don't know if your application is one where you could take advantage of using hard service cord.

 

[rbalex]

there are some cases where you can use hard service cord in at least some classified areas. I don't think SO cord is listed as hard service though.

without looking real close at the applicable code sections I don't know if your application is one where you could take advantage of using hard service cord.

Actually, Type SO is "Extra Hard Usage" [Table 400.4] and where Section 501.140 applies, it's fine.

Do you actually believe that I don't know when Section 501.140 would apply?

 

[petersonra]

Actually, Type SO is "Extra Hard Usage" [Table 400.4] and where Section 501.140 applies, it's fine.

Do you actually believe that I don't know when Section 501.140 would apply?

It was a response to this comment in one of the OP's posts.

I kinda wondered on the SO cord but was not sure as I have seen talk about its use in Haz locations.

 

[gadfly56]

I usually recommend starting with you insurer. I'm always surprised when they don't get intimately involved with a classified facility.

If they aren't helpful, I'd contact a professional engineer. Fortunately, paint facilities can usually be classified directly from NEC Article 516. I would suggest using the 2014 Edition. It is detailed and well updated.

I would not suggest contacting your local building authorities until after the classification/design is complete.

How about NFPA 33 "Spray Applications Using Flammable or Combustible Materials"? They do reference NEC 505.5 (2005) in section 6.3 Electrical Area Classifications, but the whole standard is specifically for the OP's operation.

 

[rbalex]

How about NFPA 33 "Spray Applications Using Flammable or Combustible Materials"? They do reference NEC 505.5 (2005) in section 6.3 Electrical Area Classifications, but the whole standard is specifically for the OP's operation.

If you read the IN to the NEC [2014], Article 516 Title you'll find the relevant information is extracted from NFPA 33 and 34. They are also both referenced in [2014] Section 500.4(B) IN 4.

Since the OP was discussing Division rather than Zone classification, Section 505.5 is basically irrelevant although it is more or less the Zone system's analog to Section 500.4.

There is nothing relevant in either NFPA 33 or 34 with regard to area classification that isn't in NEC 2014, Article 516. AND Since the NEC is a Code rather than a Standard it usually has greater force unless the local jurisdiction has specifically adopted them. This is one of the reasons I specifically recommended the Article.

 

[gadfly56]

If you read the IN to the NEC [2014], Article 516 Title you'll find the relevant information is extracted from NFPA 33 and 34. They are also both referenced in [2014] Section 500.4(B) IN 4.

Since the OP was discussing Division rather than Zone classification, Section 505.5 is basically irrelevant although it is more or less the Zone system's analog to Section 500.4.

There is nothing relevant in either NFPA 33 or 34 with regard to area classification that isn't in NEC 2014, Article 516. AND Since the NEC is a Code rather than a Standard it usually has greater force unless the local jurisdiction has specifically adopted them. This is one of the reasons I specifically recommended the Article.

OK, I'll buy that.

 

[sandsnow]

Do you actually believe that I don't know when Section 501.140 would apply?

Knowing you Bob, that's funny.