What is the normal operating pressure of a fire main system?

The normal operating pressure of a fire main system is typically set at 150 psi. This pressure provides an adequate flow rate and volume of water to effectively combat fires while ensuring that the system components, such as pumps, valves, and pipes, can withstand the pressure without risk of failure.

Maintaining this pressure enables firefighters to effectively operate hoses and nozzles, ensuring that water reaches the required height and distance during a fire emergency. A lower pressure might not provide sufficient flow, particularly in larger buildings or in scenarios requiring multiple hose lines. On the other hand, higher pressures, such as 200 psi or 250 psi, could lead to stress and potential damage in the piping infrastructure and equipment.

Therefore, 150 psi represents a balance between operational efficiency and structural safety, making it the standard choice for fire main systems.