Section 250-91(b) (1996 NEC) allows the use of emt as the grounding conductor of a circuit. My question concerns whether the common type emt fittings will provide continuity or if some type of bonding connector should be used? What is normal in the industry?
EMT fittings will safely carry ground fault currents At least the steel ones will, some of the zinc die cast don't perform as well, mainly because the locknuts sometimes won't penetrate the paint on some boxes or fixtures.
Many electricians around here also install an equipment grounding conductor inside the conduit. We've all seen fittings that have loosened or have had the conduit pulled out & when that happens, there is no ground downstream from the break.
I personally pull in a seperate equipment ground in any conduit likely to get abused. I don't bother to do this with conduits that are 20 feet in the air, but once you drop down to 10 feet or so they can be easily damaged.