Which gauge is used to measure the gallons per minute flowing from a fire hydrant?

The Pitot Gauge is specifically designed to measure the velocity of water flowing from a hydrant, which can then be converted into a flow rate expressed in gallons per minute (GPM). It operates by measuring the difference in pressure between dynamic pressure (the pressure of the moving water) and static pressure (the pressure exerted by the water at rest). By using this pressure differential, the Pitot Gauge determines how fast water is flowing, allowing for accurate calculation of the flow rate.

Understanding this tool is crucial in fire hydrant testing as it provides necessary data for evaluating the hydrant's performance and ensuring that adequate water flow is available in case of an emergency. The other types of gauges serve different functions: pressure gauges measure the static pressure within the system, flow meters can measure flow but are not specifically designed for hydrant use, and temperature gauges monitor the temperature of the water rather than its flow rate.