According to the National Fire Protection Association 13, pressure-regulating valves should be installed on standpipe risers where static pressures exceed what value?

The correct value for installing pressure-regulating valves on standpipe risers, according to the National Fire Protection Association (NFPA) 13, is 175 psi. This standard is established to ensure the safety and effectiveness of fire protection systems in managing pressure levels that could potentially cause malfunction or damage to the standpipe system.

When static pressures exceed 175 psi, the risk of over-pressurizing the system increases, which can lead to issues such as leaks, rupturing of pipes, or the malfunction of valves and fittings, resulting in compromised performance during emergencies. The implementation of pressure-regulating valves helps to maintain pressure within a safer operational range, ensuring adequate performance while mitigating risks associated with excessively high pressure.

While the other values may be relevant in different contexts or standards, NFPA 13 specifically identifies 175 psi as a threshold for the incorporation of pressure-regulating devices in standpipe systems, highlighting the importance of adhering to established safety protocols in fire protection engineering.