A fire fighting pump is a water-powered pump used for the emergency delivery of water for fire suppression. These pumps are installed on fire fighting trucks or set up as portable units to draw water from a nearby water source. They may be a centrifugal, turbine or positive displacement style pump arranged in either a horizontal or vertical configuration.
These units generate NFPA 1901 rated flows up to 2250 GPM (8515 LPM) depending on the model. A single-stage centrifugal design minimizes piping requirements while providing reliable operation. The streamlined one-piece body provides easier access to the impeller and mechanical seal. It also allows the unit to be mounted lower on the truck, which frees up space for additional equipment or crew members.
Pumps are sized based on the number of floors, occupant classification and potential hazards. When determining the size, it is important to understand how much friction loss will be experienced and take into account when using the pump. This is done by calculating the flow rate, discharge pressure and nozzle application. Taking into account friction loss will ensure that the nozzleman receives enough water to keep the fire under control, but not too much water which can create dangerous situations.
It is vital that the fire fighting pump be maintained regularly to ensure proper performance. This includes changing the oil and filters on a regular basis, ensuring that hoses are properly inspected and secured, checking for air infiltration of the suction strainer, hose water heater, high water temperature switch and cooling water solenoid valve operation. Also, the system should undergo annual testing that puts the pump through its paces using actual water. This allows technicians to compare the results to the original design specifications and ensure the pump is performing effectively.