What is the primary use of 5-inch hose?

• A. Used for interior attack lines
• B. Pumper receives water from hydrant (supply hose)
• C. For fog streams on scene
• D. Used to drain water to a pond

Answer: (B)

The main idea is that a 5-inch hose is used as a water supply line to bring large volumes of water from a hydrant or other source to the pump. Its big diameter minimizes friction loss, so the engine can receive enough water to feed the attack lines. This is different from interior attack lines, which use smaller hoses to deliver water at higher pressure directly to a nozzle for applying the fire. Fog streams come from specific nozzles and smaller-diameter lines, not from a supply hose. Draining water to a pond isn’t a typical fire-ground use for this hose. So, its primary role is to provide a continuous water supply to the pumper from hydrants or other sources.