Which material is most likely accepted by a gas company for interior gas piping?

The correct material widely accepted by gas companies for interior gas piping is yellow brass. Yellow brass, composed primarily of copper and zinc, is known for its strength, corrosion resistance, and ability to withstand high pressures. These properties make it suitable for gas applications where safety and durability are paramount. Furthermore, yellow brass fittings provide a secure and leak-resistant seal, which is crucial for gas distribution systems to prevent hazardous leaks.

In many jurisdictions, gas codes and standards typically recommend or allow yellow brass for gas piping connections and fittings because of its reliability and performance characteristics. When selecting materials for gas piping, it's essential to consider both the structural integrity and the compatibility with natural gas or propane, which yellow brass offers effectively.

As for the other materials listed, stainless steel could be acceptable in some applications but might not be the first choice compared to yellow brass for interior gas piping. Plastic PVC is not typically approved for gas piping because it lacks the necessary strength and temperature resistance required for gas transport. Aluminum is also generally not preferred for gas piping as it may not provide the same level of integrity and durability as yellow brass or even stainless steel, and it can be susceptible to corrosion in certain environments.