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In a repair garage, the area up to 18" is considered a Class 1 Div 2 location.
These folks did put in the required conduit seals at about 20", but I think there's still a problem.

What do ya think?

Are those EMT connectors coming into the bottom of the sealoffs???

Certainly are!
So, what's the problem?

Well, EMT isn't allowed in a Class 1 Div 2 area per 501.4(B), assuming that this is power wiring not exempted under 501.4(B)3.

If the conduit is rigid or IMC, then the use of EMT connectors on it would be a violation of listing requirements under 110.3(B).

You got it right on the money, but
This one's double-trouble!.
Although not shown, right up above is a panelboard.
That's a waterline to a drinking fountain.(Why would anyone run a 3/4" plumbing feed to a single drinking fountain?)...S

[This message has been edited by electure (edited 11-11-2003).]

Electure, did you check to see if the sealoffs were filled?

Roger

Would somebody please "translate" this into layman's terms?

Some areas in repair garages are considered "classified areas", primarily because of the potential for fuel vapor buildup. Wiring in such areas is subject to very demanding requirements, including the use of rigid or IMC conduit, threaded connections, explosionproof boxes and fixtures, and proper sealing to prevent flammable vapors from moving through the conduit to remote locations.

The fittings shown here are called "sealoffs" or "EY seals", and are used to physically seal the conduit at the boundary of the hazardous area. After the wires are pulled, a liquid sealing compound is poured into the fitting (through the plugs with the square recesses), which fills up the spaces around the wires and prevents flammable vapors from passing the seal.

The use of EMT fittings could allow flames and hot gases from a vapor explosion inside the conduit system to ignite the surrounding atmosphere. Only threaded connections are allowed here.

The requirements for wiring in hazardous locations are spelled out in Articles 500 and 501 of the NEC.

Maybe the water line will rupture and put out the fire after the explosion. a 3/4 line would really help then

I pulled one of the plugs, and yes, these were poured. There was even a little dab of NoAlox, or some anti-sieze lube, on the threads of the plug!
The waterline run through the dedicated space for the panelboard is a violation as well.

TG, before the liquid is poured in, a fiber material is driven into the conduit to keep the liquid sealing compound (one mfr. calls their's "Chico") from pouring down the conduit.

Thanks for the explanation!

Reminds me of the saying that a chain is as strong as its weakest link...

There are occasions that sealoffs are installed, and they don't get poured.

They're made in both horizontal and vertical pour versions (and some that swivel), but none that can defy gravity...S

[This message has been edited by electure (edited 11-14-2003).]

Electure,
With the filling compound in the conduit, if you need to remove a wire for some reason, is this still possible?.
Or does this stuff stay liquid?.
BTW, this is the only area of work here in New Zealand where Steel Conduit is still required.
I've done a few "Hazardous Area" jobs- equivalent to the US "Classified Areas", sort of.
Just in Service-Stations and Spray-Painting Booths, nothing too serious!.

I second Roger's inquiry .. I have never seen a filled sealout that didn't have slop-over on the sides .. that looks too clean and would suspect that the sealouts are not filled. ERFERTT

Well, you have got the prints to ID the electrician who installed them. Send him the red tag!

Trumpy

As one who lives in the Exp. prf. world, let me answer your question. Yes, chico can be removed sometimes, I 've done it many times. In fact I've done without hurting the wires and have pulled new ones right beside the old ones. I've also seen bad daming so the Chico went down the pipe and made the pipe unusable. Patience, a dull screw driver and a shop vac works to remove the old compound.If you are pulling all new wires its easier to replace the fitting.
I could drive around and show you hundreds of sealing fittings with nothing in them. . I poured about 20 or so last week on a job. We used existing pipes and none of them were sealed when we started

The work is incorrect, not sloppy.
To slop a bunch of compound onto the threads of the closure/inspection plug will make it much harder to inspect the sealoff.(I've had to take them apart with an impact wrench, borrowed from the mechanics).


The bottom picture's seal is obviously not filled...S



[This message has been edited by electure (edited 11-21-2003).]