A fire apparatus pump is able to deliver what percentage of its capacity at a 15 ft lift?

A fire apparatus pump's ability to deliver water at varying lifts is crucial for effective firefighting operations. At a 15 ft lift, a pump can generally deliver about 70% of its capacity. This percentage accounts for the energy required to lift the water vertically, which affects performance.

When water is lifted, the pump must overcome gravitational forces, which consumes some of the overall pumping capability. The 70% figure reflects the typical efficiency of pumps under these conditions, indicating that although the pump can still function well, its maximum flow is reduced compared to situations where there is little to no lift involved. Understanding these dynamics is essential for fire service personnel to make informed decisions on water supply management during an incident.

The other percentages listed, such as 100, 50, and 30, do not accurately represent the performance of the pump at that height. A 100% lift would imply full capacity with no loss, which isn't feasible at a significant lift due to their inherent design limitations and operational physics. Similarly, a 50% or 30% output would suggest greater inefficiencies that typically do not occur when the pump is optimally positioned at a 15 ft lift. Knowing this helps fire service operators assess their equipment's performance and plan