What minimum conditions must Nonmetallic Pipe withstand?

What minimum conditions must Nonmetallic Pipe withstand?

• A. 150 psi at 100°F
• B. 175 psi at 120°F
• C. 200 psi at 90°F
• D. 180 psi at 150°F

Answer: (B)

Nonmetallic piping in NFPA 13R must be tested to ensure it can handle the pressures it may face in service, especially when temperature rises. The standard specifies a minimum hydrostatic test condition of 175 psi at 120°F for nonmetallic pipe. This accounts for the fact that plastic materials lose strength as temperature increases, so testing at an elevated temperature ensures the pipe will still perform safely under realistic fire conditions. In practice, this means the system is pressurized to at least 175 psi while the water is at about 120°F to verify there are no leaks or weaknesses. The other options don't meet this defined combination of pressure and temperature, so they don't satisfy the required minimum.

Nonmetallic piping in NFPA 13R must be tested to ensure it can handle the pressures it may face in service, especially when temperature rises. The standard specifies a minimum hydrostatic test condition of 175 psi at 120°F for nonmetallic pipe. This accounts for the fact that plastic materials lose strength as temperature increases, so testing at an elevated temperature ensures the pipe will still perform safely under realistic fire conditions. In practice, this means the system is pressurized to at least 175 psi while the water is at about 120°F to verify there are no leaks or weaknesses. The other options don't meet this defined combination of pressure and temperature, so they don't satisfy the required minimum.