What does a flow meter directly measure during a test?

During a test, a flow meter directly measures the flow of water in gallons per minute (GPM). This device is integral to assessing how much water is being delivered by the fire department's apparatus in real-time. By measuring the quantity of water flowing through the system, it allows for accurate calculations regarding the effectiveness of the water supply and pumping system.

The flow meter's ability to provide real-time data on water flow helps in evaluating whether the system meets the required flow rates for firefighting operations. Understanding the flow rate is critical, as it informs firefighters about the availability and adequacy of water supply necessary for effective firefighting efforts.

While other measurements like total pressure in the system, temperature of the water, or pump efficiency are important for overall system performance and operational understanding, they are not the direct function of a flow meter. A flow meter focuses solely on the measurement of water flow, ensuring firefighters have the information needed to respond effectively in emergency situations.