Which standard defines pipe thread measurements for natural gas piping?

• A. ASME B1.20.1
• B. ISO 7
• C. JIS B 0203
• D. DIN 2999

Answer: (A)

Pipe-thread measurements for natural gas piping are defined by a standard that specifies the thread form, pitch, diameters, and tolerances used for pipe connections. In the United States, that standard is ASME B1.20.1, which covers general-purpose pipe threads including the National Pipe Takered Thread (NPT). This ensures that fittings, valves, and other components machinate together to form a proper, leak-tight seal when tightened with appropriate sealant.

Other standards like ISO 7, JIS B 0203, and DIN 2999 describe thread forms used in different regions or systems and have different dimensions and tolerances, so they wouldn’t be appropriate for typical US natural gas piping under NFPA 54 guidelines.