Which formula can be used to estimate gallons-per-minute in a smooth bore nozzle?

The formula to estimate gallons-per-minute from a smooth bore nozzle is based on the nozzle diameter and the nozzle pressure. The correct formula is (29.7)(d²)(NP), where "d" represents the diameter of the nozzle in inches and "NP" refers to the nozzle pressure in pounds per square inch (psi).

This formula is derived from hydraulic principles and is used commonly in the fire service to calculate flow rates accurately. The constant 29.7 is a factor that accounts for the conversion from cubic feet per second to gallons per minute, making it particularly useful for operations that involve firefighting nozzles, which typically utilize smooth bore designs.

Using this formula ensures that fire operators can deliver the appropriate amount of water at effective pressures, which is critical for extinguishing fires and monitoring firefighting operations accurately. Understanding this relationship helps operators optimize their firefighting efforts based on nozzle size and pressure settings, leading to more effective and efficient fire suppression tactics.