emt in concrete

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Robert Graves said:
Thanks, I did see 358.10B, ( corrosion protection) what is considered corrosion protection with EMT?
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The handbook comes in handy here:

According to the 2001 UL General Information for Electrical Equipment Directory (White Book), category FJMX, galvanized steel electrical metallic tubing (EMT) installed in concrete, on grade or above, generally requires no supplementary corrosion protection. Galvanized steel electrical metallic tubing in concrete slab below grade level may require supplementary corrosion protection. In general, galvanized steel EMT in contact with soil requires supplementary corrosion protection. Where galvanized steel EMT without supplementary corrosion protection extends directly from concrete encasement to soil burial, severe corrosive effects are likely to occur on the metal in contact with the soil.
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(The above if from the '02 NECH)
So all you have to do is find the UL General Information for Electrical Equipment Directory (White Book) :)





Oh look....






here it is :D
GENERAL INFORMATION FOR ELECTRICAL EQUIPMENT DIRECTORY 2005


(In .pdf format)
 
Don't they make concrete fittings for EMT? I am pretty sure I used them in the past, or thought I was using them.
 
My only question is why would anyone use EMT in concrete? I know it may be done in other places, but not here. PVC is so much cheaper and easier than "slabbing" EMT.
 
peter d said:
My only question is why would anyone use EMT in concrete? I know it may be done in other places, but not here. PVC is so much cheaper and easier than "slabbing" EMT.
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When you turn your nieties up out of the slab. Your ready to go.
Some job specs, read no pvc. Emt is much easier then rigid.
 
buckofdurham said:
When you turn your nieties up out of the slab. Your ready to go.
Some job specs, read no pvc. Emt is much easier then rigid.
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Here we would use a RMC 90 and a short stub of RMC to turn up. Never EMT.
 
IMO, EMT and PVC are well suited for slabs. If near or on the ocean PVC for the first floor only, then EMT or NM for the rest.
Did anyone see the show LA hardhats? They were using smurf tube in the slab. Now that is where I would draw the line. Hack would be the term.
 
John Valdes said:
IMO, EMT and PVC are well suited for slabs. If near or on the ocean PVC for the first floor only, then EMT or NM for the rest.
Did anyone see the show LA hardhats? They were using smurf tube in the slab. Now that is where I would draw the line. Hack would be the term.
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I dont see a thing wrong with using smurf in a slab, thats pretty much what it is designed for.
 
peter d said:
My only question is why would anyone use EMT in concrete? I know it may be done in other places, but not here. PVC is so much cheaper and easier than "slabbing" EMT.
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Cuz pvc shatters in the cold. Sometimes you gotta use emt in pour where concrete buggys run over pipes in slab cold weather applied.
 
quogueelectric said:
Cuz pvc shatters in the cold. Sometimes you gotta use emt in pour where concrete buggys run over pipes in slab cold weather applied.
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As I said, standard trade practice is to use RMC where it emerges from the slab here.
 
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