What type of tubing is referenced for copper brazed steel tubing?

The correct reference for copper brazed steel tubing is ASTM A 254. This standard specifically pertains to the requirements for copper and copper alloy tubing that is intended to be joined by brazing, ensuring that the materials used meet the necessary strength and performance criteria for high-temperature applications.

ASTM A 254 addresses various aspects such as material composition, mechanical properties, and testing methods designed for brazed joints, which are crucial for maintaining the integrity and safety of gas systems. Compliance with this standard helps ensure that the design and installation of piping systems adhere to the best practices and safety guidelines outlined in the National Fuel Gas Code.

The other standards listed pertain to different materials or applications which do not specifically cover copper brazed steel tubing. For instance, ASTM A 106 is related to seamless carbon steel pipe for high-temperature service, ASTM B 88 pertains to seamless copper water tubing, and ASTM D 3020 addresses thermoset plastic tubing. Thus, they do not apply to the requirements needed for copper brazed steel tubing.