NEC article 500

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Ranger86

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This is going to sound like a dumb question .... hehe...
If a structure that does not have power (no service) is used as a storage facility for flammable liquids (class I liquids). The liquids will be stored in sealed drums.
Does the NEC article 500 still apply? or does this building have no electrical hazardous location classification?
Thanks for your input.
 

rbalex

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Ranger86

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Las Vegas, NV
Yes.

It depends. [See Section 500.5(B)(2) Informational Note No.2. As we often say, the determination must be made by someone qualified to do so and familiar with the installation.]

You're welcome

OK, thanks, that is what I was leaning too, but had to hear it from another colleague. The informational note mentions that the quantity of material is a factor in the determination, which helps in the decision making.
thanks again.
 

don_resqcapt19

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Illinois
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I am a bit confused. If there is no power, how does anything in the NEC apply given the wording of 90.1(A)?
(A) Practical Safeguarding. The purpose of this Code is the practical safeguarding of persons and property from hazards arising from the use of electricity. This Code is not intended as a design specification or an instruction manual for untrained persons.
 

rbalex

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I am a bit confused. If there is no power, how does anything in the NEC apply given the wording of 90.1(A)?
Let's face it, that's as much a statement of philosophy as anything. (Although I love, "This Code is not intended as a design specification or an instruction manual for untrained persons.")

Reading a bit further in Section 90.3 we find:
90.3 Code Arrangement. ... Chapters 5, 6, and 7 apply
to special occupancies, special equipment, or other special
conditions. These latter chapters supplement or modify the
general rules
. Chapters 1 through 4 apply except as amended
by Chapters 5, 6, and 7 for the particular conditions.
Technically, area classification has nothing to do with electricity at all. A location's area classification is based on processes and geometry. It's Standards like NFPA 497 and API RP 500 that states area classification is for the purpose of selecting electrical installations. Technically, even Section 500.1 doesn't even come right out and say that - it simply says how the rules apply to electrical installations.

A key idea is "Unclassified Location" is defined as,"Locations determined to be neither Class I, Division I; Class I, Division 2; Class 1, Zone 0; Class I, Zone 1; Class 1, Zone 2; Class II, Division I; Class II, Division 2; Class III, Division I; Class III, Division 2; Zone 20; Zone 21; Zone 22; or any combination thereof." "Determined" means it has actually been reviewed by someone qualified to make the judgement, since "[T]his Code is not intended as a design specification or an instruction manual for untrained persons."
 

Ranger86

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Location
Las Vegas, NV
It turns out that this building falls under "warehousing" and in NFPA 30 table 7.3.3, the classification is "ordinary" or non-classified. Also in NFPA 30, section 9.12.1 applies to this building, containers are always sealed, electrical area classification shall not be required.
 
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