Pump Operations

Tank Time

Estimate how long onboard water lasts at a steady discharge rate.

What It Tells You

The approximate duration of the apparatus tank at the current flow.

Formula

Time (minutes) = tank gallons ÷ GPM

What the Variables Mean

tank gallons
usable onboard water gallons
GPM
total discharge flow gallons per minute
Time
estimated duration minutes

Plain-Language Explanation

Every open discharge draws from the tank. Higher total flow empties the tank sooner.

Worked Example

A 750-gallon tank is flowing 250 GPM.

  1. Time = 750 ÷ 250
Time = 3 minutes

Fireground Takeaway

Tank time is an estimate. Communicate early and establish a sustained water supply before the tank is empty.

Practice This Formula

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