View Full Version : Gas line safety question

03-08-2010, 10:08 PM
A shop I know are moving in a large gas oven and plan to run the Natural gas line in a cut out in the cement floor where all the electrical lines are stored. There is diamond plate covering the cutout in the cement floor. The reason all the electrical supply lines are in the floor is due to the overhead crane. They are going to use inhouse labor to install the new gas line. None are plumbers. Is this not something that osha should know or is this type of work allowed in industry? I have always thought that the people who install gas line have to be certified.

03-08-2010, 10:17 PM
THe question of certified or not being required varies by area. A quick call to your local utility company would give you a correct answer for your locality.

Here, no certifications are required for standard black iron pipe. Speciality products such as tracpipe require a manufacturers certification (pass a test) before you can purchase the product.

03-08-2010, 10:22 PM
Thanks for the reply, I was just concerned about poor insulation possiblity's in a area where high voltage in at. Also being below floor level would be a could collection area of gas that might not be detected until the first spark.
The place where this is going to be done has a safety engineer and I guess I should trust his judgement.

03-08-2010, 10:46 PM
Natural gas is lighter than air and will not accumulate in low spots.
If they have electrical shorts in the trench gas will be the last thing to worry about.
Most places I have worked plant maintainance personel are allowed to do anything in the plant except new construction. Installing a machine is not new construction.
Tattling to OSHA is a good way to make sure that you are not welcome at ANY shop.

03-08-2010, 10:51 PM
Id make sure at least someone in charge knows of your discomfert in this 'inhouse' gas install, and maybe double check on the installer to make sure they test every single connection for leaks.

03-08-2010, 10:51 PM
I am glad to learn that the gas will not collect in a low place. You are right about contacting osha. Thats why I posted my concerns on this forum. I just did not want someone to get hurt or killed by cost reductions, but maybe my concerns were not needed.

03-09-2010, 01:45 AM
over here the line must be done by a registered competent person, plastic coated copper is the preferred tube, electrically cros bonded both ends, earthed that is with appropriate clamps, adequately supported at regular prescribed centers for the clamps, sand covered is preffered to keep the cables away from it, and a clearly visable shutoff valve each end of the underground section, gas warning tape/ribbon layed over the pipe, to identify it, the plastic coat on the pipe over here is bright yellow.
over there its probably similar but you have permits and the like to get before you can do it so it gets inspected and tested. we try over here to not be putting joints below in side if possible as the pipe is on a roll up to 50m x 22 mm dia.
How does gas registration work in the US?

03-09-2010, 09:12 AM
Every where around here that I have worked always had a bonded plumber on staff who either did the work or watched and approved. But the code does change depending on where you are located. Local building inspectors are often given a bit of "home rule" based on common issues that they come across.

If you have a good manager that you can talk to I would side with the previous advice about asking if one of the installers was bonded or if they planed to have a bonded plumber look over the install.


03-09-2010, 09:39 AM
well if you get a gas leak cause someone did not do a proper seal , you wont have to worry about jesus comming back you'll meet your maker sooner then expected.. for where you want to place the gas lines in with all that electricial id never do it ,i might be a bit off at times when i havent had enought sleep.but even i know you dont mix elecrical near a gas line..

03-09-2010, 10:07 AM
rebel54, call your local gas company and ask about running a gas line in a pit with electric lines. Codes may vary but something tells me this is not a good idea.

03-09-2010, 10:29 AM
Rented Kawasaki Trencher, layed out line location as was given from Union Gas People. Was xtra careful had another guy assisting, in 10 seconds we cut through the feed line to House (buddy ran away as he had a smoke in his mouth LOL) i ended up pinching line with vice grips. Odd thing,,, they made me dig a 4 foot deep trench for my gas line to the shop yet there (union gas line ) was 10 inches below ground. The Gas repair guy came and he watched me take some digital pictures of the Broken line with a tape measure beside it. I did not have to pay for the repair. He wrote down i hit it with a shovel? Odd rules they have, I also bribed the repairguy with a pair of my homemade drink holders. Didnt wish to find a xpensive repair bill on my otherwiswe zpensive gas bill. I also had a pair of moron gas fitters do dumb ass **** like drill through 2 x 6 support to feed gas pipe into my new shop for the hydronic Heating? Amazes me the crap...

03-09-2010, 10:43 AM
Around here (on my plant site) you will find electrical, water, and gas all in a common trench. However, the electrical wiring is in conduit.

As far as gas line goes, as long as a pressure/leak test is done, there should be no real issues. After installation, one end of the pipe is capped, the pipe is charged with high pressure (around 50-60 lbs) air, and a pressure gauge is installed for 24 hours. No pressure change? Good pipe. Pressure change? Get the snoop leak detector out. After that is completed, the cap should be removed and the entire run should be purged with high pressure air to rid the pipe of any dirt, threading swarf, or oils (don't stick your face over the outlet. A lot of crap will probably exit the pipe). Hook up both ends, turn the gas on, and snoop for leaks at both end connections. Fire oven.


Mike Folks
03-09-2010, 05:52 PM
If the new plumbing for the gas line is the standard black iron pipe, I'd say make sure the threads will be leak resistant.

I've heard about horror stories if the Chinese black iron pipe leaking as the male and female threads are not made correctly. Maybe running a tap and die over the pipe will help.

03-10-2010, 07:00 AM
Running gas is not a huge deal. Your electrical (if up to code) should provide little possible trouble for a gas line. I cut my own threads... the tools are cheap and your runs can be more flexible WRT how you route them.

Sizing the pipe and proper support should concern you more. Have a few isolation valves to make new work/troubleshooting leaks easier.

Utilities are notorious for not knowing where their own lines are. They will mark what they (think they) know but don't be surprised if you find out they are wrong.

03-10-2010, 08:38 AM
I have installed natural gas in two houses we lived in, one black iron and the other copper at 2 psi. The only requirement is that it pass inspection, I don't need any special training or qualifications. My first installation was passed on the first inspection, on the second the inspector never bothered to come out and look at it.

As for running a gas line in a raceway the only real issue is the amount of raceway fill involved. Per code you may only fill the raceway a certain amount in order to ensure adequate conductor cooling. An electrician will know the correct code requirements in your area. Also, the gas line must be identified as such. Here that is done by either taping or painting it yellow. Code here allows common burial of gas and electric service to detached garages so I expect that there would be no issue in a floor trench that is used as a raceway other than the fill percentage.