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Differences between Class 1 Division 1 and Class 1 Division 2?

Differences between Class 1 Division 1 and Class 1 Division 2?

Differences between Class 1 Division 1 and Class 1 Division 2?

(OP)
What are the differences between Class 1 Division 1 and Class 1 Division 2?

If someone can tell me or point me to a site or source for such a rookie question, it would be greatly appreciated.

RE: Differences between Class 1 Division 1 and Class 1 Division 2?

In what context?

Good Luck
--------------
As a circle of light increases so does the circumference of darkness around it. - Albert Einstein

RE: Differences between Class 1 Division 1 and Class 1 Division 2?

The definitive reference is the National Electrical Code Chapter 5.

Class I locations are ones in which hazardous vapors may or do exist.  The difference between Div 1 and Div 2 is the level of expectation that hazardous levels will be present.

Note that Classes are given a Roman numeral and Divisions an Arabic numeral.

Infomation on the particular substance is found in the NEC Handbook, and NFPA 497.  Information on particular types of installations are found in later articles in the NEC.  For example, bulk storage plants are in Article 515.

Regards,
William

RE: Differences between Class 1 Division 1 and Class 1 Division 2?

(OP)
Thanks Weh3 for the infomation,check last paragraph.

RE: Differences between Class 1 Division 1 and Class 1 Division 2?

You'e welcome.

William

RE: Differences between Class 1 Division 1 and Class 1 Division 2?


I think this thread belongs to the Occupational safety forum or to the NFPA code issues forum. Do you agree ?

RE: Differences between Class 1 Division 1 and Class 1 Division 2?

In this thread are found, in five short posts, the language issues of

Terminology
Spelling
Notation

Actually, either the IEEE code issues or the electrical power issues forum would have been the place to bring it up.

Regards,
William

RE: Differences between Class 1 Division 1 and Class 1 Division 2?

CONTEXT IS IMPORTANT!

While william was obviously sufficiently familier with these terms that that context was clear,  shouldn't all of us put our questions and comments in context?

For example,  here's a similar question to the original:

"What's the difference between Type V, Class 6, Grade C,
and Type V, Class 7, Grade D?"

I think all will agree that I'm unlikely to get a good response without putting this in proper context.

RE: Differences between Class 1 Division 1 and Class 1 Division 2?

You're right, mshimko.  Until now, I did not even understand the CajunCenturion's question about context, because the terms are ones I deal with all the time.

However, the original question may have been based on all the information that Lecutus had.  To pose the question in context, etc. would have required him already to possess the very knowledge that he was seeking.

For a bit of background that I had assumed:

The question concerns classified (hazardous) locations, which are defined in NEC 500-1 as follows:

"Articles 500 through 504 cover the requirements for electrical and electronic equipment and wiring for all voltages in Class I, Divisions 1 and 2; Class II, Divisions 1 and 2; and Class III, Divisions 1 and 2 locations where fire or explosion hazards may exist due to flammable gases or vapors, flammable liquids, combustible dust, or ignitible fibers or flyings."

The class has to do with the type of material (whether vapor, dust, or fibers); the division has to do with the level of expectation that a hazard will exist in a given area.

More specific information regarding the various classes and divisions is found in the subsequent sections of the NEC.

European installations are classified according to Zones.  Although the NEC contains a Zone system and allows you to use either the Class/Division system or the Zone system, there is not necessarily a one-to-one correspondence between Class/Division and Zone.  What it all comes down to is the types of equipment you can use in a particular area.

Regards,
William

RE: Differences between Class 1 Division 1 and Class 1 Division 2?

william:

The "context" I think is needed is much simpler, and broader than what you're think of.

I'm refering simply to field of study (electrical, fire protection, rocket science, etc) and perhaps just a little more?   

In the original question, adding "Electrical Codes", or perhaps "Locations in various electrical code requirements" would provide sufficient additional information.  (Had this been an "electrical forum", this would probably not be needed).

In my example about,  the proper context would be "....in military epoxy coating specifcations".

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