conduitelectricalelectrical-panelgroundingsubpanel
I have read here that metal conduit can be used as the ground and you needn't then pull a separate ground wire:
What are the NEC rules governing this?
How do you avoid "weak ground" links between conduit segments?
Are there safety considerations?
Do you have to clamp bond wires between segment couplers, or should the couplers and their interface to the conduit be sufficient?
Do ground-conduits need to be rated as such?
Other considerations?
Pull out the wire that's in conduit, (look it over, but it's probably just fine) pull in that wire and a ground.
It's darn near impossible to pull in another wire without pulling the whole bundle out and back in. It's fairly straightforward to pull the whole bundle out, add a wire and pull back in, unless the conduit is too small.
Code-wise, (250.118) properly installed metallic conduit (RMC, IMC or EMT) is a ground, whether or not you personally like it. It's not copper, but it's got a large cross-sectional area and the fittings are designed to maintain contact if properly installed.
I would not consider Romex an upgrade. I've seen too much rodent/Romex interaction to love it much, and with the possible exception of wire old enough to use cloth-based insulation as primary there's little benefit to "new wire" over "old wire."
This is a bigger can of worms than meets the eye. There are huge arguments over all this.
This is a coax grounding block:
This is a grounding bar:
This is a grounding bridge, your cable company or telephone company probably has one on the outside of the house at the electrical service entrance:
What I'd do:
Edit:
There is a good chance your patch panel doesn't ground the coax that goes through the house. However if you use surge strips that have a coax port in those places, and the coax has been terminated properly so the body of the plugs are bonded well to the shiled, and the outlets those surge strips plug into have a good ground, you should be fine.
One last thing - this whole thing hinges on good grounding of your electrical system. If you want to be really careful there, have an electrician check the grounding and bonding and if possible ground resistance. This is IMO worth doing in general.
Best Answer
You are not allowed to use any wiring method, except for specific wiring methods listed (enumerated) in the back half of NEC Chapter 3. (The Article 300s). Therein, you will find an article for each allowed wiring method.
Where a wiring method allows use of the pipe as the ground, it will specifically say so in that article.
Select an appropriate wiring method.
Note that you can change wiring methods anywhere appropriate, such as from EMT to NM at a junction box, or EMT to Rigid at any appropriate coupler.
In a few cases you can also use a wiring method inside a wiring method, e.g. you could carry NM-B past the first junction box in conduit, through the conduit, to the second box and splice it there, if the conduit is large enough to allow this. Just in case you're all out of THHN wire :)
Not as "ground-enabled" (your term), no.
However the conduit must be rated and UL listed for the wiring method which you are using. If you select the IMC wiring method, you must use pipe listed and labeled as IMC.
If you are working up a plan to use leftover plumbing or general-use pipe as a wiring method, forget it, but it may be usable as a damage shield for another wiring method such as UF which needs one.
By following the rules for the wiring method, and NEC 110.2 which requires you use [UL] approved equipment, and NEC 110.3(B) which requires you obey labeling and instructions of equipment.
If you do all that, then the NFPA Code committees and UL have done all the heavy lifting for you.
You need to follow the NEC article for the wiring method, and other NEC rules as may be applicable. For instance if you bring 1” conduit into a 1-1/2” knockout, using adapter washers, you must provide for ground continuity some other way.
Lastly if the installation is making you nervous, review your understanding of Code regarding the part that makes you nervous. If it still makes you nervous, throw a ground wire in the pipe.