Corrugated Stainless Steel Tubing (CSST)
CSST is a flexible, stainless steel pipe used to supply natural gas in residential, commercial and industrial structures. CSST is often coated with a yellow, or in some cases, a black exterior plastic coating.
CSST should not be confused with flexible natural gas appliance connectors – the product that joins an appliance to your home or building's natural gas supply line. The difference is that flexible connectors attach directly to the appliance from the wall or floor, while CSST is usually routed beneath, through and alongside floor joists in your basement or crawl space, inside interior wall cavities and on top of ceiling joists in attic spaces.
If lightning strikes a structure containing CSST, there is a risk the lightning can travel through the structure's natural gas piping system and cause a leak, or in some cases, a fire.
If you find CSST in your home or business, customers should have a licensed electrician install a bonding device to reduce the chances of a natural gas leak or fire.