What is the nozzle pressure for smooth bore hand lines?

Smooth bore hand lines are typically designed to operate at a nozzle pressure of 50 psi. This pressure is considered optimal for achieving a balance between stream quality and effective reach. At this pressure, the water is expelled in a cohesive and straight stream, which is essential for effective firefighting, especially in penetrating a fire or reaching spots where water needs to be applied.

Using this nozzle pressure allows firefighters to maximize the friction loss and other hydraulic factors while ensuring they maintain control of the nozzle. Lower pressures could result in inadequate reach or ineffective coverage, while higher pressures may lead to difficulties in managing the nozzle, especially for personnel who may not be as strong or experienced.

However, in certain circumstances or specific guidelines set by some fire departments, variations might apply, but the standard and widely accepted nozzle pressure for smooth bore hand lines is indeed 50 psi.