After years of inspecting, we had never seen grounding wires connected to a gas meter before. But in 2022, we noticed a sudden uptick in observing grounding wires connected directly to the gas meter.
SoCal Gas has also noticed this, issuing an article of their own here, warning Solar Panel installers to not ground the electrical system to a gas meter. In addition, on their contractor’s page, SoCal Gas warns “Do not use SoCalGas gas meter gas piping gas risers or related equipment for electrical bonding or grounding because it is not safe and not permitted.”
A search online shows several confusing articles, as grounding wires, bonding wires, and tracer wires can be easily confused.
Grounding Wire
A grounding wire is, as the name implies, a wire that connects the electrical system to the ground. This is a significant safety item to prevent excess electricity from building up in the home, which could lead to a fire or electrocution. While a grounding wire does not always carry current, it is intended to carry electrical current at any time. Often grounding wires are connected to a grounding rod, which is a steel rod inserted 8 feet into the ground. It’s also common to attach the grounding wire to the home plumbing system as the copper pipes coming into and out of the home are underground. As a gas pipe is also connected to the house by running underground, it seems logical that a gas pipe is a good place to connect a grounding wire.
However, this is prohibited by the California Plumbing Code Section 1211.3 “Gas piping shall not be used as a grounding conductor or electrode.”
Bonding Wire
A bonding wire is designed to connect components that could absorb electrical currents. In case any stray electricity gets into the components, electricity will flow through the bonded components rather than gather in any one component. Bonding a gas line is often done at the water heater, per California electrical code 250.104 (see the article Top 10 Myths of Water Heater Installations). The main difference is a grounding wire is designed to carry current at any time necessary and carry that current into the ground. A bonding wire is not designed to carry current, rather it only allows current to pass through it if electricity somehow gets into the bonded components.
Bonding is covered for gas pipes that are not CSST in California Plumbing Code Section 1211.1
Each above-ground portion of a gas piping system that is likely to become energized shall be electrically continuous and bonded to an effective ground-fault current path.
CSST gas lines are covered in California Plumbing Code Section 1211.2.
For more about CSST, read our article The California Corrugated Stainless Steel Tubing Act
Tracer Wire
A tracer wire is a thin wire that follows a gas pipe underground. It’s often confused as some sort of grounding connection. When there is a reason to locate where the gas pipe is (such as digging in the area), the tracer wire can be connected to a small low voltage electrical charge. Then using special equipment, a professional locater can detect the voltage in the wire to trace the path of the gas pipe. A tracer wire is usually not connected directly to the meter, though it can be.
Book your home inspection by calling 818-298-3405 or book online here.
Note: IM Home Inspections does not perform gas pipe tracing.