Corrugated Stainless Steel Tubing (CSST) Safety and Regulations
Corrugated Stainless Steel Tubing (CSST) is a flexible gas pipe used to carry natural gas or propane in homes and buildings. It is often covered with a yellow plastic coating and installed inside buildings. CSST is commonly used in residential, commercial, and industrial properties.
Why is CSST a safety concern?
If lightning strikes a building or nearby area, electricity can travel through gas piping systems. In some cases, this can damage CSST, causing gas leaks or fires.
To reduce this risk, gas piping systems should be properly bonded and grounded. Bonding helps safely direct electrical energy and lowers the chance of damage.
If your home has yellow CSST, it is strongly recommended that you contact a licensed electrician to make sure your system is properly bonded and grounded.
Maryland CSST Laws
Maryland law limits the use and sale of certain types of CSST.
In 2022, the Flynn and Laird Act prohibited the use of non-arc-resistant jacketed CSST in:
- New construction with natural gas or propane systems
- Renovation projects affecting more than 50% of a property’s total square footage
- Projects that add a new gas line to an existing gas system
In June 2025, Maryland passed additional legislation that prohibits selling, offering for sale, transferring, or distributing non-arc-resistant jacketed CSST in the state.
What homeowners should know
- Check whether your home has yellow CSST gas piping
- Have a licensed electrician inspect bonding and grounding if needed
- Use arc-resistant CSST for new installations or renovations that fall under Maryland law