Originally Posted By: dhartke This post was automatically imported from our archived forum.
A couple days ago I was talking to a friend who has worked at the local municipal gas department for many years. He told me copper tubing was not allowed for propane or natural gas anywhere in his jurisdiction and whenever it was found during a city inspection it would be removed and replaced with black iron pipe and flexible stainless steel tubing as needed. They have been enforcing this rule so long he couldn’t remember the origin, possibly a reaction between copper and gas.
Does anybody have an explanation or a link that would explain this?
Originally Posted By: afernbaugh This post was automatically imported from our archived forum.
Before there was an efficient method for treating natural gas there was the likelihood that some (or most) of the gas produced contained sulphur (sour gas) compounds in amounts that could effect the strength of the copper tubing.
Modern gas treatment plants remove these compounds to such an extent that copper may be used, but the old rules of use persist.
Originally Posted By: dvalley This post was automatically imported from our archived forum.
David,
Gas lines connected to water heaters should be made only of approved gas line materials. Copper is not one of them; gas can cause a copper line to deteriorate from the inside out. In such a case, a qualified company or contractor should be contacted to replace the line with a more appropriate material.
Originally Posted By: Blaine Wiley This post was automatically imported from our archived forum.
In Virginia almost all of the builders in the last five to seven years have gone to flexible copper tubing for gas lines (both natural and LP) which are run off of a manifold system. They were approved for usage somewhere in the mid nineties (I bet Robert O knows when) and are very prolific.
The only requirement for appearance was that all copper gas lines had to be painted bright yellow to distinguish them from water lines. 
Originally Posted By: Guest This post was automatically imported from our archived forum.
Hi David,
Everywhere in the world except the US, copper is used extensively for natural gas piping. The copper institute recognizes the application and makes suggestions to use K soft copper.
I couldn't find any information or rules that prohibited the use of copper for natural gas in my area and my local utility company said "sure you can use it." The one advantage of using copper is it eliminates a lot of joints and the connections can be flared instead of threaded.
There was some hoo haw about sulfur in natural gas corroding the copper but that was a long time ago around here.
I wanted to put a gas line to my second floor and it would have required either an untested joint in iron piping to be concealed in the wall or I'd have had to tear out the wall to test the joint or use soft copper. I used the copper. Chad
Originally Posted By: dhartke This post was automatically imported from our archived forum.
Thanks Chad,
It is interesting that different AHJ's in different areas can have completely opposite opinions on something so common with such great potential
danger.