It’s a fire risk you probably have in your home, without even knowing it.
Investigative Reporter Mike Rush reveals how this well-intentioned product has sometimes played a part in fires that destroyed property and took lives.
CSST Info and Issues: 5 Questions
What is CSST?
Corrugated Stainless Steel Tubing (CSST) is a stainless steel pipe that is flexible and is used to conduct natural gas and propane. Experts say it was originally used in earthquake-prone Japan in the 1970s and ‘80s to minimize gas line breaks during a quake and any fires afterward. Its success there then led to it being used in seismically-active California.
But its flexibility also made it attractive to home-builders and by the 1990s it was being used in residential, commercial, and industrial construction all over America. Now millions of homes use CSST for conveying gas.
So what’s the issue?
Engineers and fire safety officials say that in lightning active areas, a problem was first noticed. When lightning struck near or actually hit the home, the energy from the lightning would eventually “arc” or make its way to the gas-filled CSST lines. Since the steel walls of the tubing were made thinner to make it flexible, in some cases the energy of the lightning would cause it to puncture, creating small holes that would release the flammable gas. That in turn would sometimes lead to a home or building fire.
How many homes get struck by lightning each year?
U.S. Fire Administration figures show that every year more than 7,000 homes catch fire due to lightning. Government information also shows that Missouri is often one of the Top Ten or Twenty states for most lighting activity.
If CSST was used in the construction of my home, where will I find it?
It is often found running through attics, in the floor support struts that can be seen from your basement, and connected to appliances such as a water heater. It also often runs inside the walls of your home.
How can I check and improve the safety of the CSST in my home?
First, have it examined by a qualified, licensed electrician to make certain that it is properly grounded and bonded. This reduces the risk of an electrical surge causing damage to the tube and releasing any gas.
However, experts from such organizations as the Lightning Protection Institute and other fire prevention organizations say that you also might want to look into “a lighting protection system” for your home. They say these systems can be expensive but offer a greater level of protection than simple grounding.
In addition, the manufacturers of what is called ‘black CSST’ say their newly-developed product is far-more resistant to, or even eliminates the problem of lightning surges and resultant fires. So if you have yellow CSST and are concerned, black CSST is an option. However, some electrical engineers say the current formulations for the product may still not resistant enough whe it comes lightning electrical current.
Those engineers are lobbying with the industry and other safety organizations for further improvements in the design and manufacture of the tubing. Lastly, some experts say that if necessary, you could always go back to traditional, heavier, less-flexible steel-gas tubes with collar-joints or fittings.
However, as some CSST manufacturers point out, those joints have to be regularly checked for loosening and for leaks, whereas the ‘joint-less’ CSST product does not.