FPE Calculator

Velocity (ft/s):
Weight (grains):


About FPE Calculator (Formula)

A Fire Pump Efficiency Calculator is a specialized tool used in fire protection engineering to evaluate the efficiency of a fire pump system. Fire pumps are crucial components in fire sprinkler systems, responsible for delivering water at the required pressure to extinguish fires effectively. The efficiency of these pumps is a critical factor in ensuring the system’s reliability during an emergency.

Formula for Calculating Fire Pump Efficiency (FPE):

The Fire Pump Efficiency is calculated using the following formula:

FPE (%) = (Water Horsepower Output / Brake Horsepower Input) x 100%


  • FPE (%) represents the Fire Pump Efficiency, measured as a percentage.
  • Water Horsepower Output is the actual power delivered to the water by the fire pump.
  • Brake Horsepower Input is the power input to the fire pump, typically measured using a dynamometer or an electrical power meter.

In this formula, the efficiency of the fire pump is determined by comparing the water horsepower output, which represents the useful work done by the pump in delivering water, to the brake horsepower input, which is the total power supplied to the pump. The result is multiplied by 100% to express the efficiency as a percentage.

Significance of FPE:

The Fire Pump Efficiency is a critical parameter for several reasons:

  1. Reliability: A high FPE indicates that the fire pump system is operating efficiently, ensuring that it can deliver water to the fire sprinkler system at the required pressure and flow rate when needed most.
  2. Energy Efficiency: Calculating FPE helps identify potential energy waste in the fire pump system. A lower efficiency may indicate mechanical issues or the need for maintenance and adjustments, ultimately saving energy and reducing operational costs.
  3. Safety: In firefighting situations, the effectiveness of the fire pump system can be a matter of life and death. An efficient system ensures a faster and more effective response to fires, enhancing safety for occupants and firefighters.
  4. Compliance: Many safety regulations and building codes require regular testing and maintenance of fire pump systems, including assessing their efficiency. Calculating FPE helps ensure compliance with these standards.


The Fire Pump Efficiency Calculator plays a crucial role in assessing the performance and reliability of fire pump systems. It helps maintain safety, energy efficiency, and compliance with regulations, making it an essential tool in fire protection engineering and building management. Regular monitoring and maintenance of fire pumps based on FPE calculations are vital for ensuring the effectiveness of fire suppression systems in critical situations.