Hydrostatic testing for the specified standpipe systems must be performed at least every how many years?

• A. 1 year
• B. 3 years
• C. 5 years
• D. 10 years

Answer: (C)

Hydrostatic testing checks the strength and tightness of the standpipe piping system by filling it with water and pressurizing it to a level above normal operating pressure to look for leaks or failures. For specified standpipe systems, the test interval is set at every five years, ensuring the system remains capable of withstanding its designed pressure over time without requiring overly frequent testing. Shorter intervals like one or three years would be more burdensome without added safety benefit, and waiting ten years risks deterioration going unchecked. So five years is the standard, per typical fire protection standards.