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how would this be any different for the plumbers working on the water main when the neutral was opened?

You are correct and I wish we did not subject the water workers to this either. [Linked Image]

There have been threads on the forums about water company's that do not allow the water pipe to be used a grounding electrode, they install a dielectric fitting before the meter and do not allow it to be jumped.

Then of course when a water pipe is separated the product that leaks out is not flammable. [Linked Image] If there was current in the gas line when they break a union the resulting spark may not be welcome.

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How would any elevated potential develop on grounded pipes? wouldn't the OCPD clear any faults?

If the service neutral opens all grounded objects will be have an elevated potential to earth. This is particularly true if you have a plastic water main, as you will not be connected back to the source through your neighbor. This has nothing to do with the OCP.


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I would think an ungrounded gas pipe would be more dangerous to the gas man, if a hot wire gets laid on the piping, what would clear the fault, assuming that the gas pipe is servicing a non-electrical appliance?

Here IMO is where it gets cloudy, which is more likely? A bare hot wire contacting and remaining against a gas pipe or a service neutral opening.

It has been my experience that the service neutral opening is more common but my experience means nothing I would really be interested in facts and figures. [Linked Image]

I also would ask again why the NEC used the words "may become energized" if they did not want some choice in the matter.

It would be simple for the NEC to state

"Gas Pipes Shall be bonded"

But they did not. [Linked Image]

Anyone else have some input? [Linked Image]

Bob

Bob Badger
Construction & Maintenance Electrician
Massachusetts