One sprinkler head operates at what pressure (NP)?

• A. 60 psi (NP)
• B. 20 psi (NP)
• C. 30 psi (NP)
• D. 15 psi (NP)

Answer: (C)

Sprinkler heads are designed to deliver a dependable discharge only when they receive a sufficient amount of pressure at the head. For a standard head in a typical system, the published operating pressure at the head is around 30 psi. This level provides a reliable flow rate to achieve the intended spray pattern and coverage while accounting for minimal friction losses in a simple branch line. Pressures much higher than this (for example, around 60 psi) would push more water than necessary and can affect the spray pattern or cause unnecessary water damage, whereas pressures that are too low (like 20 or 15 psi) may not produce an adequate discharge or reach, resulting in ineffective protection. Therefore, 30 psi represents the conventional operating point that balances flow, pattern, and coverage for a single sprinkler head.