What is the pressure at the highest sprinkler head in the system?

• A. 10 PSI
• B. 15 PSI
• C. 20 PSI
• D. 7 PSI

Answer: (B)

The pressure at the highest sprinkler head is determined by the water’s ability to reach that elevated point, which means elevation and friction losses lower the pressure as water climbs. Sprinkler heads are designed to operate within a specific pressure range, so the system must deliver enough pressure at the top to meet that requirement after all losses. In this scenario, the value that matches the highest head’s required operating pressure—given the losses in the system—is the one that properly ensures the top head will discharge. The other options would not align with the head’s operating pressure once those losses are accounted for, so they wouldn’t reliably actuate the highest head.