38-mm (1½-in.) attack hose typical flow range?

38-mm (1½-in.) attack hose typical flow range?

• A. 473-757 L/min (125-200 gpm)
• B. 189-473 L/min (50-125 gpm)
• C. 757-946 L/min (200-250 gpm)
• D. Over 946 L/min (250 gpm)

Answer: (B)

For a 38-mm (1½-in) attack hose, the typical flow when using a standard nozzle at practical pressures is about 50–125 gallons per minute (roughly 190–470 L/min). This range reflects a balance: enough water to effectively cool and knock down the fire, while keeping friction losses along the hose and nozzle reaction at a manageable level for a handline. Pushing beyond about 125 gpm would require higher pressures and/or larger hoses, which increases friction losses and makes the line harder to control. Too little water (below ~50 gpm) wouldn’t produce an effective attack. So the best match for this hose size is the 50–125 gpm range.

For a 38-mm (1½-in) attack hose, the typical flow when using a standard nozzle at practical pressures is about 50–125 gallons per minute (roughly 190–470 L/min). This range reflects a balance: enough water to effectively cool and knock down the fire, while keeping friction losses along the hose and nozzle reaction at a manageable level for a handline. Pushing beyond about 125 gpm would require higher pressures and/or larger hoses, which increases friction losses and makes the line harder to control. Too little water (below ~50 gpm) wouldn’t produce an effective attack. So the best match for this hose size is the 50–125 gpm range.