Outlet And Switch Grounding In The Metal Wall Box ?

Hello,
Let me try to ask this in an understandable way.
Been many, many years since I wired any outlets, switches, etc., so possibly the building codes have changed ? (live in Mass.)
Previously, when you installed or replaced a switch, outlets, or even a GFCI, it was "required" that you run a green grounding wire from the back of the metal box where you would have a screw grounding together the box, and All the green wires from the outlets, etc grounds to the switch or outlet grounding screw.
It was not allowed, I think, to just have the mounting tabs do the grounding thru the box shell, although the mounting tabs were (usually) common with the outlet or switch grounding screw.
I now see that Leviton implies for their their GFCI devices that you can simply use the mounting tabs, and that a separate ground wire to the box grounding screw is not required.
Do I have this right ? Has the code changed.
Just use the GFCI mounting tabs, and don't run a separate ground wire ?
Or,...?
Thanks, Bob
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On Tuesday, July 18, 2017 at 8:00:26 AM UTC-4, Bob wrote:

As long as the device is listed for use that way, that's correct, it's self-grounding when installed in a metal box.
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Bob, if you are positive the box is grounded, then run a pigtail from a ground screw in the box to the GFCI. If there is a separate ground wire in the circuit, connect that to the GFCI (and to the metal box).
Obtaining a ground through the tabs and mounting screws is possible, but many times, in order to get the outlet to mate properly with the wall cover plate, the outlets tabs are not always snug up against the box. In that case, the electrical ground would be only through the threads of the screws, which, IMHO, is less then desirable.
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On Tuesday, July 18, 2017 at 9:50:42 AM UTC-4, Stormin' Norman wrote:

His question was if self-grounding is allowed. The answer is NEC allows it, as long as the receptacle is listed for that purpose, which many are.
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On Tue, 18 Jul 2017 07:25:32 -0700 (PDT), trader_4

Thanks for your input.
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On Tue, 18 Jul 2017 14:35:51 +0000, Stormin' Norman

You were always allowed to use the tab for grounding if at least one of the fiber, screw retention, washers was removed and the tab was made up tight to a metal box. (not hanging out on "drywall ears") What changed was the product. As Trader points out, newer spec grade devices have a metal spring in one of the mounting tabs that makes direct contact with the mounting screw and gives you a better ground. It is legal but I am still not sure I would trust my life to it with anything but a GFCI, although an Arc Fault breaker is to some extent a GFCI. It operates at a 30ma level on a ground fault.
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On Tue, 18 Jul 2017 11:21:28 -0400, snipped-for-privacy@aol.com wrote:

I do not disagree with what you have written. However, I have seen many older installations with poorly grounded or ungrounded boxes.
My perspective of code is; it is the bare minimum acceptable to pass inspection. If one makes good, wired ground connections, with a degree of redundancy, it will not only meet code, but exceed it.
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On Tue, 18 Jul 2017 15:34:14 +0000, Stormin' Norman

Ungrounded boxes have not been legal since the Eisenhower administration but I agree there has always been bad workmanship and sloppy inspection.
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On Tue, 18 Jul 2017 12:33:27 -0400, snipped-for-privacy@aol.com wrote:

Well, he is in Mass with metal boxes so, who knows how old his electrical system is?
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On Tue, 18 Jul 2017 18:04:05 +0000, Stormin' Norman

It is easy enough to test. I recommend something like the good Suretest or an Ecos and not a regular VOM tho since they actually test under a load. Unfortunately they may not detect a bootleg ground tied to the neutral if that happens more than ~20 feet from the place you are testing. It will find one right in the same box tho. They want <1 ohm but more than zero.
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