What equipment considerations are involved in selecting hose sizes for a given attack plan?

What equipment considerations are involved in selecting hose sizes for a given attack plan?

• A. Only the hose length matters.
• B. Hose material and color determine performance.
• C. Consider required GPM, friction loss, nozzle pressure, hose weight, maneuverability, and coupling compatibility; choose size to meet friction loss limits while staying manageable.
• D. Hose size is chosen solely by the price.

Answer: (C)

Sizing hose for an attack plan revolves around balancing the needed water flow with what the pump can deliver and what the crew can safely handle. Start with the required gallons per minute at the nozzle for the planned action, because the attack effectiveness depends on getting that flow to the fire. Then consider friction loss: the longer the hose and the smaller the diameter, the more pressure is lost along the hose before the water reaches the nozzle. You choose a hose size that keeps this friction loss within what the pump can supply so the nozzle still hits its required pressure.

Nozzle pressure matters because the nozzle must be fed at a specific pressure to produce the desired spray pattern and reach. The chosen hose size should deliver enough pressure at the nozzle after accounting for friction loss and any other losses in the run. At the same time, hose weight and maneuverability come into play—larger, heavier hoses are tougher to handle, advance, and feed through structure or stairs, so the size must be practical for the crew to work with under the given conditions. Coupling compatibility is also essential; you need hoses and adapters that fit with the pump and nozzle to maintain a reliable, uninterrupted flow.

In short, the best choice weighs GPM needs, friction loss, nozzle pressure requirements, hose weight and handling, and coupling compatibility, selecting a size that achieves the needed nozzle performance without overburdening the crew or the equipment. Price or color alone do not determine suitability, and material or length aren’t the primary factors in sizing for an effective attack.