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Marc M
07-20-2011, 09:50 PM
Anyone have information regarding the separation of fuel and electric in the same trench? I thought it wasnt allowed or local utility stipulated then I heard you can combine the two with 6-12" of dirt separating the two. Anyhow, need some type of clarification if possible.
Thanks

Jerry Peck
07-21-2011, 05:23 PM
Can't think of anything prohibiting that practice.

But I do believe that regulator vent needs to be 3 feet from that building opening (crawlspace vent).

Marc M
07-21-2011, 08:13 PM
I know about the vent, panel and window clearances. I just thought there was something I read about them not sharing a trench due to the possibility of explosion.

Gunnar Alquist
07-21-2011, 09:29 PM
Anyone have information regarding the separation of fuel and electric in the same trench? I thought it wasnt allowed or local utility stipulated then I heard you can combine the two with 6-12" of dirt separating the two. Anyhow, need some type of clarification if possible.
Thanks

Marc,

This is from PG&E.

Marc M
07-21-2011, 09:32 PM
Marc,

This is from PG&E.
Thank you Mr. Gunnar.. I found something close, but not with this much detail.

Jerry Peck
07-22-2011, 06:11 PM
I thought about this aspect this morning, it is something to consider: There are two gas pipes running under that concrete walkway (at least one, the supply to the meter, and possibly two, the supply from the meter to the house.

That is similar to the gas piping being beneath a floor, there is no place for the gas to gradually escape, as such I would consider this requirement:
(bold and underlining are mine)
- G2415.11 (404.11) Piping underground beneath buildings. Piping installed underground beneath buildings is prohibited except where the piping is encased in a conduit of wrought iron, plastic pipe, or steel pipe designed to withstand the superimposed loads. Such conduit shall extend into an occupiable portion of the building and, at the point where the conduit terminates in the building, the space between the conduit and the gas piping shall be sealed to prevent the possible entrance of any gas leakage. If the end sealing is capable of withstanding the full pressure of the gas pipe, the conduit shall be designed for the same pressure as the pipe. Such conduit shall extend not less than 4 inches (102 mm) outside the building, shall be vented above grade to the outdoors, and shall be installed so as prevent the entrance of water and insects. The conduit shall be protected from corrosion in accordance with Section G2415.8.

If the gas piping leaks, the above will prevent the gas from accumulating beneath that slab, the gas will vent up to the outdoors between the gas pipe and the sleeve.

H.G. Watson, Sr.
07-22-2011, 09:46 PM
What trench? I don't see a trench! What underground or through-the-foundation building entrance? I see pipes through-the-wall of the building! If anything, I suspect the other customer-side pipe penetration to the concrete sidewalk/patio/pool deck is for a pool type heater and/or an outdoor gas grill or similar appliance.

I see a gas supply pipe and a branch encased in concrete and apparently run under a patio or pool deck, neither with a sleeve, one at a scored control crack point with expanding foam insulation about it, and the other cracking.

The gas lines require sleeving and protection for their penetration and run under the patio/sidewalk/pool deck slab where there is insufficient cover between the concrete sidewalk and the gas line. I recall further isolation/protection requirements in certain siesmic regions, however do not know if this was superceeded with recent statutory changes/code adoptions. I suspect you may indeed have regional ammendments applicable, and without knowing the property location, would recommend research at a local level.

As far as whether or not the supply to the meter is customer owned and customer jurisdiction at this point, I offer no opinion as am unclear as to the jurisidiction and the status of de-regulation/regulation in your State presently, although I highly doubt that the pictured is a public way.

However, I think I see another safety issue. Both the Utility and the customer side gas shut-off valves appear to have been coated/painted over and possibly fouled. Neither appears to be easily or reliably in ready operable condition with the coating present and could present a safety issue should either or both need to be operated, specifically CLOSED (ex. seismic event, fire, flood, gas leak, etc.).