Ex vs AEx Rating - Manufacturer Listing

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cowski

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Does anyone have experience finding "AEx" rated equipment for Zone 1 in the US? This would be per Article 505 (and not acceptable with the Class / Div ratings covered earlier in 500, right?).

The Ex rating seems very common, but that's not acceptable in the US(right?). Has anyone used equipment with the Ex rating only? (or asked their JHA if they would accept Ex in their situation?)

I assume the AEx rating would have to be produced by FM or UL (or the other national testing lab whose name I can't remember). They would be using a slightly modified version of IEC standards that are also harmonized with US standards (right?).

Or maybe I'm completely misunderstanding this....

Thank you!
Phil
 

rbalex

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The "A" indicates that a US NRTL has certified the product. It is not limited to UL or FM; i.e., CSA, ETL, etc., may also certify a product to "AEx." The primary technical reason for the appended "A" is that "Ex" products are not necessarily tested for "ordinary locations." i.e., minimal "general purpose" requirements.

I have specified simple "Ex" products in the past, but then I've done quite a bit of international design.

An AHJ may approve simple "Ex" products if you can show that they are equivalent to "AEx." See Section 500.8 (A)(3). This approval would be unlikely since any US domestic manufacture would probably make AEx products in the first place, and an AHJ would not accept a foreign manufacturer's documentation. FedOSHA definitely wouldn't.
 

cowski

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Engineer
Thanks Bob.

What's your opinion of this Ex rated conduit? It's UL listed as flexible metal conduit. Would that be considered "AEx"? (the UL listing certifies general purpose requirements).

Are there AEx products on the market yet? I haven't seen anything.
 

rbalex

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Its UL listing would permit it to be used anywhere LFMC is permitted. The other various European ratings are irrelevant.
 
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