Ground pigtails with conduit

[Charles]

I'm installing exposed EMT conduit in my garage. The whole system will be in the conduit, which will be used for the ground. I'm unclear on whether I'm required to run ground pigtails from outlets and switches to the back of the boxes. It seems pointless since the ground screw on the outlet/switch is screwed into the same physical piece of metal that makes up the mounting flange that screws into the box. I believe I'm okay to leave it off with the outlets because the packaging they come in says "grounding", is that right? How about the switches, should they say "grounding" too (these ones don't)? Thanks for any advice.

[RBM]

"grounding" means that it is a three prong outlet. What you need is "self grounding" which has a brass clip on one of the attachment screws.

[DanG]

Check with your AHJ. I'm fairly sure they no longer accept conduit ground, at least not here.

[George]

I don't think using conduit as the equipment ground has been acceptable for a while.

[RBM]

It is recognized by the current NEC

[terry]

Not sure about your jurisdiction but am of opinion that use of the conduit as the grounding conductor is not now acceptable in most places in North America. So in addition to the current carrying conductor live, neutral etc. a grounding wire should also be run and incidentally 'grounded' to each junction box etc. in approved manner. Could be an insurance liability issue if something happened, for the sake of omitting a single conductor! Quite apart from safety, be careful not to invalidate your insurance.

[Wayne Whitney]

Conduit as the EGC is recognized by the NEC, and in fact if the conduit installation is done properly, there are studies suggesting it is a better conductor than a copper wire EGC. Of course, that's the rub, each conduit connection has to be made up properly, while a copper wire EGC is continuous from box to box.

Cheers, Wayne

[RBM]

As a practical matter, I prefer to pull en egc, so I don't have to be concerned about loose fittings, however NEC 250.118 lists EMT as an acceptable method.

[Charles]

The inspector specifically told me I could use the conduit as ground. If you don't, do you run a ground wire for every circuit? I'm running as many as 4 pairs through some sections. Running 4 more ground wires would be killer. It would force me to double up conduit or go to larger diameter.

I found outlets that specifically said that they were properly grounded when attached to a grounded box. Is there an equivalent thing for switches? I couldn't find it. Some boxes are just so darned packed with stuff that not having to deal with ground wires makes a big difference. (those #@^&# GFCI's take up tons of voume!)

What's the point of grounding a switch anyway?