The pressure rating (PSI - pounds per square inch) of a fire pump can vary depending on the specific design and application requirements. Fire pumps are designed to deliver water at high pressures to effectively suppress fires. The PSI rating of a fire pump is determined by factors such as the size of the pump, the capacity (flow rate) it can deliver, and the pressure needed to meet the fire protection system's requirements.

Typically, fire pumps used in commercial buildings, industrial facilities, or municipal firefighting systems are designed to deliver water at pressures ranging from 100 PSI to 350 PSI or more. These higher pressures are necessary to overcome the friction loss in the fire protection piping network and to provide sufficient pressure at the firefighting equipment, such as fire sprinklers or hose lines.

It's important to note that the PSI rating of a fire pump is just one aspect of its overall performance. Fire pumps are also rated based on their flow capacity (GPM - gallons per minute), which is equally crucial for effective fire suppression. The combination of flow rate and pressure ensures that the fire pump can deliver the required amount of water at the necessary pressure to control or extinguish fires.

The specific PSI rating of a fire pump will be determined during the design phase of the fire protection system, considering factors like the building's size, occupancy, fire hazards, and local fire codes and regulations. Fire protection engineers and specialists play a vital role in selecting and designing the appropriate fire pump and ensuring it meets the specific needs of the building or facility.