US adoption of Zones: is there any?

[Fieldbus]

Years ago, Europe had Zones (0,1,2) for hazardous areas and the US had Divisions (1,2) under NEC500. They were not identical and of course, local preferences led to divergence in methods of installation: Increased Safety (Exe) is very popular in Europe and Flameproof is very popular in the US. Now that the NEC has been updated to include the concenpt of Zones, a version of increased safety called AEx is potentially available for US users, but the plant has to be classified with Zones according to NEC505.

Has anyone know of any US plant(s) classified with Zones, rather than Divisions? As I understand it, these are mutually exclusive, so you can't put Class I Div 1 motor in a Zone 1.

 

[controlnovice]

A major oil company I worked with talked about the possibility of using the Zone method, but I think they ended up not going that direction because we weren't building anything new.

I don't know of anyone in the States using the Zone method for a Stateside plant.

Try asking this in the "Electrical/Electronic engineering other topics" forum. You may get a better response.

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This is normally the space where people post something insightful.

 

[Fieldbus]

Thanks for that - question posted over there!

 

[Ashereng]

You may want to include a link to your other post?

"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?

 

[danw2]

For reference, Factory Mutual (FM) has a poster, 'Expert Guide to Hazard Locations Poster' at

http://www.fmglobal.com/pdfs/P0296HazardousLocations2.PDF

The poster shows that Class 1, Div 1 has been divided into 2 zones by NEC505. On the FM poster, the small print in the upper right "Area Classification" breaks that down as,

Zone 0 Flammable Material, Present Continuously (worst case)
Zone 1 Flammable Material, Present Intermittently

But note that Class 1, Div 1 covers both Zone 0 and Zone 1, (presumably as long as the permitted groups are valid for the area)

The problem as I see it, is not putting a Class 1 Div 1 motor in an area historically rated Class 1, Div 1, rather it's putting a Class 1, Zone 1 motor in an area that has historically been rated Class 1, Div 1; without that area having been re-classified according to the "flammable material present intermittently" criterion.

Dan