Hazardous location

[drwill]

I am getting ready to pick up a remodel job at a propane company's office. what would their classifcation be if (1.) no bottles are in office.(2.)bottles are stored in office.
The reason behind this question is that the prints call for new flourescent fixtures, and removal of old devices(receptacles and switches)and installing new ones. only problem I dont know if they are spec grade or explosion proof devices.
any thoughts or words of advice will be appreciated.

drwill

 

[indcom]

Re: Hazardous location

My first action would be go to the GC & have them find out from the EE what is required. That's their job.
If this is a quote/bid job - what did you bid & how did you obtain your info? Did you do a pre-jobsite visit & check it out?
Not trying to berate you, just need a little more info to see if I can be of some help.

 

[bphgravity]

Re: Hazardous location

1. I believe would be unclassified.

2. I believe could be classified as Class I, Division II, Group D.

I would not make that determination on your own. Get the AHJ to make the call. The fire marshal, insurance agent, or possibly the building department will assist in making this decision.

 

[friebel]

Re: Hazardous location

To: drwill,
The information that "indcom" gave you is right on track.
If you are not knowledgeable about electrical classification in hazardous areas, and it seems to me that you are not, by the questions that you are asking, then you need to get someone who can assist you in the proper procedure for determing the proper classification.
I would suppose that your work is going to be inspected by the AHJ, so you will need a plan print of the area to be classified.
Again "drwill", get someone who is knowledgeable, and you will also learn a great from this excercise.

 

[petersonra]

Re: Hazardous location

Good advice. Somewhere there is a floorplan that show how the area is classified. The GC should get this for you.

My experience is that the AHJ will not want anything to do with classification of the area on his/her own (unless the AHJ happens to be the plant engineer).

 

[coulter]

Re: Hazardous location

drwill -

It's rare (maybe never) that I've seen full propane bottles stored in an office area. There are office machines, and maybe a heater under the clerk's desk, all in the area - not a good place for storing full propane bottles. With that in mind, I'm real reluctant to offer any advice without knowing more about the job.

Your question makes it sound as though you may not be familiar with explosion-proof wiring. If that's true, and you are thinking of doing electrical in classified areas, you need to be. So, here is some light reading for you to get started:

NEC articles
500 General classified, using divisions
501 Class 1, flammable liquids and vapors
505 Classified using Zones - not applicable but some good guidance
515 Bulk plants - may not apply, check the scope

NFPA 497 RP for classification flammable liquids, vapors

NFPA 30 Flammable liquids code

NFPA 58 Liquified petroleum gas code

Maybe also API RP 500

You are going to need documentation which is usually an area classification drawing - the AHJ should insist on one. The NEC isn't very good at picking an area classification unless the application just happens to exactly match one of the special occupancies. So, who ever does the documentation, needs to be familiar with the guiding industry standards. Where I am, that would require either an engineer working for the owner company, or if a contractor does it, a PE.

The other way I have seen small jobs done, is to copy the existing methods in the area. If the area is C1, D1, then the new stuff is C1,D1. In this case, you have to go look at the existing. This works only if you are not changing the use of the area. And if there is an AHJ watching, they still may want an area classification dwg - they should.

I wouldn'd expect the AHJ to help pick out the classification. Why would they want to?

1. They likely do very little with classified areas, so are not familiar with industry practice.

2. And if it is screwed up and blows up they don't want their name on it and shouldn't have to.

Good luck

carl

 

[George Stolz]

Re: Hazardous location

At the risk of sounding like a buzz-kill, doesn't the initial question sound like a straight swap-out-devices type of job? Even the lighting change sounds like a swap.

 

[drwill]

Re: Hazardous location

505.7 (A) SUPERVISION OF work.
Classifications of areas and selection of equipment and wiring systems shall be under the supervision of a qualified professional engineer.
I believe that this is the perfect solution. I will get the company's engineer to give me documentation as to which classification this is under, taking the responsibility from me. This also takes the need for any electrician to really understand section 500 as the engineer will make all those decisions.(I'm being facetious)

Thanks drwill

 

[rbalex]

Re: Hazardous location

drwill,

Unless the location is classified by "Zones," Article 505 doesn't apply. What does apply, no matter what the classification method is:

500.4 General.
(A)Documentation. All areas designated as hazardous (classified) locations shall be properly documented. This documentation shall be available to those authorized to design,install, inspect, maintain, or operate electrical equipment at the location.