Before attaching regulator to a fuel gas valve, the recommended action is to:

• A. Clean off dirt
• B. Inspect for leaks
• C. Tighten fittings
• D. Apply thread sealant

Answer: (A)

Cleaning off dirt from the valve outlet and the regulator’s threads is the essential first step because a clean surface lets the seal sit evenly and fully contact the mating metal. Dirt, grit, or corrosion can prevent a proper seal, cause cross‑threading, or trap debris that can damage the regulator or create a leakage path once the connection is tightened. Thread sealant isn’t used for this type of fuel gas regulator connection, and can introduce contaminants or be prohibited by code, so the best practice is simply to ensure the surfaces are clean and free of debris before attaching. After the parts are clean and connected, you would then tighten to the specified torque and perform a leak check to confirm there are no leaks.