Fire Apparatus Operations and Hydraulics Practice Test 2026 – Complete Exam Prep

Relay pumping hinges on keeping the water pressure up as it travels from the source toward the fire scene. The pumper that sits in the relay line is responsible for taking the water from the source (or from the previous pumper) and increasing the pressure so the next pumper and the attack line receive adequate pressure to reach the nozzle. Friction losses along long hose lays and any elevation changes can drop pressure, so the relay pumper’s boost keeps the flow effective all the way to the fire. This is why the best description is to boost pressure between the source and the attack pumper. Drafting from a hydrant or moving to the scene without water aren’t the relay pumper’s primary roles, and delivering water directly without a relay isn’t the relay concept.