Corrugated stainless steel gas piping was invented in Japan in the 1980’s as a safety improvement over black iron piping because of its ability to flex in the event of an earthquake. Sales of standard (Yellow) CSST piping began in the US in 1990. Sales 
increased when professionals realized the installation of this type of piping could be done in 1/3 the time of rigid piping. In addition to the labor savings, contractors and code officials appreciated the ability to limit the number of fitting joints necessary.
In 2006 the manufacturers of CSST piping started requiring the thin flexible piping be bonded to protect the line from damage during an electrical surge. This is required for single-family and multi-family dwellings as part of the 2009 National Fuel Gas Code. This measure prevents damage to the piping that could result in gas leakage leading to a fire hazard.
The bonding conductor must be permanently and directly connected to the electrical service panel, the grounding conductor at the electrical service or the grounding electrode system. In the 2015 edition of the National Fuel Gas code and the National Plumbing Code limits the length of this conductor to 75 feet.
In Summary, if you observe this type of piping in your home it would be a good idea to have an electrician or plumber evaluate it for correct bonding methods as this important safety measure may prevent a fire or worse.
Source: www.CSSTsafety.com
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If you have a home inspection or home maintenance related topic you’d like to read about please send your suggestion to me via email at Aaron@Zuehlkeinspections.com
Aaron M. Zuehlke is the owner and lead inspector at Zuehlke Inspection Service, LLC, a full-service home inspection company serving Southern Wisconsin. Specializing in Home inspection, Radon Testing and residential Thermal Imaging.
