Unbiased Feedback on CSST

[M. Gatof]

There's been a lot written on the dangers of ungrounded CSST gas piping--in electrical storms, this corrugated piping can develop pinhole leaks, and houses have burned down. CSST goes under brand names GasTite, Tru-Flex.

We have a situation where a client is asking to tear out most of the CSST in her home and replace with black iron pipe. She asked the new AHJ and he is questioning. We can't get to all of it (some is in walls), but if prudent, we can get 90% of it. Two homes are involved, both served with exterior propane tanks. Dialectric unions are in place where the line enters the premises. The houses are in remote, wooded areas.

Current practices are to make a solid ground connection from point of entry of the gas line to the premises ground. Can I tell the homeowner that this will ensure safety?

I would very much appreciate real-world experience and feedback.

Thanks, Mark

[Mike Kleisch]

Personally, I don't think you can say it will be safe. Any CSST in the system is a potential for danger from lightening strikes, that’s the big issue with CSST. Plus, why would you want the burden of saying it's safe only to have something happen???

[Raymond Wand]

Also on another thread about CSST.

http://www.inspectionnews.net/home_i...tml#post232182

http://www.grefesidney.com/documents...A531161169.pdf

1. CSST gas line is extremely thin, with walls typically around 0.008" in thickness. Black iron gas pipe is typically 0.12" in thickness. Put another way, the walls of black iron pipe are 15 times thicker than the walls of CSST tubing. When this is considered, perhaps it is notsurprising that the amount of electrical energy needed to defeat traditional black iron pipe isabout 15 times more than the energy needed to defeat the much thinner walls of CSST tubing.
   
   When electrical energy from lightning is conducted through CSST tubing, electrical arcing can be created between the CSSTand any grounded metallic object, as the lightning energy seeks a ground source. This arcing can instantaneously burn a small hole, ranging fromthe size of a pin-head to a pencil eraser, right through the very thin wall of the CSST. The arcingevent can easily ignite the escaping gas being carried by the CSST, which can then serve as ablow-torch with an endless gas fuel source more than sufficient to ignite nearly any type of structure.
   
   Lightning strikes the United States more than 25 million times each year and accordingto Underwriters Laboratories (UL), lightning accounts for more than $1 billion in annual structural damage. A single bolt of lightning can carry over 100 million volts of electricity, andin reality, there are no construction methods or safety measures that can completely protect a structure from a direct lightning strike. CSST gas pipe, however, is susceptible to damage from non-direct lightning strikes as well, even strikes which may be recorded a significant distance away from the structure. “Lightning does not have to strike a building directly in order for the CSST to be affected,” explains Guy Maxwell, president of the Lightning Safety Alliance. “The reports of CSST related fires that I have seen have involved strikes that were near the structure.” CSST was originally developed in the late 1980s, but most CSST product has been installed since 2003. Any building that has had natural gas piping work done since 1990 could have CSST installed. According to the National Fire Protection Association (NFPA), no tests on the effects of lightning on CSST were conducted prior to its approval for use. One CSST manufacturer has acknowledged that the installation of a lightning protection system addresses the lightning hazard associated with CSST, yet homes with CSST are rarely equipped with lightning protection systems.

[Jim Luttrall]

If you are going to the expense of replacing it, why leave any? Copper is approved for use with propane.
I personally would not have a problem with a properly installed CSST system... but I am not going to certify that it is safe under any circumstances. It is a known defective product according to the courts and if there is a problem, the survivors lawyers are going to come after EVERYONE involved.
BTW dielectric unions should NOT be used in a gas piping system. You want the entire system to be electrically bonded, especially if CSST is used and dielectric unions would interrupt the electrically continuity of the piping system.

[H.G. Watson, Sr.]

If you are going to the expense of replacing it, why leave any? Copper is approved for use with propane.
I personally would not have a problem with a properly installed CSST system... but I am not going to certify that it is safe under any circumstances. It is a known defective product according to the courts and if there is a problem, the survivors lawyers are going to come after EVERYONE involved.

BTW dielectric unions should NOT be used in a gas piping system. You want the entire system to be electrically bonded, especially if CSST is used and dielectric unions would interrupt the electrically continuity of the piping system.

What?!?

Its a metalic gas distribution system and it begins with a dielectric union to isolate it from the delievery system components: the underground metallic delivery system or part thereof (exterior regulator, meter, etc.) , followed by a shutoff valve, (a regulator, possibly another pair of unions if a meter for utility, another valve) including a BOND to the structure grounding system, upon or just before entry.

You interrupt and break (isolate) from the cathodic protection applied to the gas distribution or the burried tank and/or underground supply from same always before entering the structure. You always have a union and if the delivery/supply is metalic a dielectric union. You then BOND the gas (structure's distrubution) piping or tubing system to the building system at the point of entry to maintain equipotential/overall bonding. You certainly employ a dieletric union whenever you're changing metals to at a minimum prevent galvanc corrosion of the metalic distribution system, or appliance connector, and to avoid the intentional charge placed upon the delivery system to prevent corrosion and avoid a Potential difference. Those isolated portions are bonded via the electric circuit's (should there be one) conductor bonding to the appliance (equipotential).

You nearly always employ a dielectric union between others owned delivery systems and the home distribution system, esp. if conductive, metallic, etc. Now a PE (plastic) utility service "line" doesn't require isolation, but that's a horse of a different color, but that union isolating from meter and still bonding customer side entry.

[Darren Miller]

I see that you are in New Jersey.
Attached find the 'official' stance the NJDCA has taken on CSST.

Some people might disagree, however, you can always hang your hat on what the code requires.

[H.G. Watson, Sr.]

I see that you are in New Jersey.
Attached find the 'official' stance the NJDCA has taken on CSST.

Some people might disagree, however, you can always hang your hat on what the code requires.

Daren Miller:

You're referring to and using OUTDATED information for NJ (2007/2008 issues of the Code Communicator) - pre CSST class action settlement corrections deadlines, btw - and pre-more recent code change cycle adoptions to UCC NJ. NJDCA has addressed in 2011 & 2012 issues of the Code Communicator (and IIRC technical bulletins & errata).

This information has been updated and corrected with NJ's code cycle updates.

For the current citations, update and current requirements for NJ: See Spring 2011 pgs 10-11 (Volume 23, No. 1); and for clarification as to "who can" (really "who may") and "who must" (who is responsible to - not just ECs) install CSST system primary bonding and where & how it must be, see Fall 2012 pgs 5 & 6 (Volume 24, No. 3).

Changes since 2007/2008 for even NJ.