What is the minimum water supply requirement for a sprinkler head to maintain a residual pressure?

The minimum water supply requirement for a sprinkler head to maintain a residual pressure is typically set to ensure that the system functions effectively during a fire event. When operating a fire sprinkler system, a residual pressure of at least 150 psi is generally required to ensure adequate water flow and coverage. This pressure helps to achieve the necessary water distribution and ensures that the sprinklers can operate properly to suppress or control a fire.

Maintaining this pressure is important because it impacts the effectiveness of the sprinklers in delivering water to the area of the fire. If the pressure drops below this level, it may result in insufficient water supply, potentially compromising the performance of the sprinkler system.

This standard is based on guidelines from the National Fire Protection Association (NFPA) and other fire protection authorities, which establish performance criteria for sprinkler systems. The selections that suggest a lower or higher pressure than 150 psi do not reflect the widely accepted minimum requirements for effective firefighting operations using automatic sprinkler systems.