Fire engines provide the movement of our most important resources, firefighters and water. A worn or damaged fire pump can have significant impact on water flow and the firefighting capabilities without showing any apparent signs of trouble to the operator on lower flow incidents. Without an efficient, effective, and reliable means to move water from point A to point B our performance and the outcome of the incident can be unsatisfactory. Testing department pumpers annually is the only acceptable way to verify your pump’s state of readiness and should be considered very important to your fleet maintenance program.
What do the changes in state code really mean? Has anything really changed? Our codes have told us in the past that we shall follow NFPA, the NFPA then told us how to perform the testing and that we shall also follow the manufacturer specification, then manufacturer specification tells us to test our pumps using NFPA 1911. So really nothing has changed but language, in the end we still need to follow the manufacturer instructions for inspection, maintenance, and testing of our equipment and pump tests are still required. All fire rated pump builders state that the pumps need to be tested on an annual basis; in addition to that, some models with other options have guidelines for the inspection of those systems as well. All of these tests can be performed by a qualified mechanic or individual that has been trained and obtained the appropriate certifications.
By following annual testing requirements a fleet manager, fire chief, or other designated person can more accurately forecast costs, needed pump repairs, and estimated downtime. This can be done by trending pump test results on a spreadsheet to chart performance. This ability to track pump degradation before it becomes an incident within an incident or an all-out failure resulting in breakdown is a must. Year by year comparisons and referencing acceptance tests can also be a good way to track pump wear.
The annual pump test will not only evaluate your pump’s performance, but should contain a concise inspection of your apparatus as well. A pump test should not be considered a preventive maintenance inspection but it should be noted that many serious problems can be spotted by this “pre- test.” It is an accepted practice to include basic fluid level checks, belts, fans, batteries, driveline condition, brake condition, adjustment, and brake holding ability, primer oil level, as well as pump transmission oil quality and more. These inspections can reveal hidden problems that may have caused the pump to fail the test or would prevent safe operation during the pump evaluation. The test is designed to simulate pumping the fire apparatus at draft for the average duration of a fire under four different pressures and three flow rates. By simulating different pressures ranges and volume requirements an evaluation of the pump’s condition can be concluded. Intake relief, discharge relief, and tank to pump flow rate are also tested. Throughout this test battery voltage, engine temperature, and transmission temperatures are monitored for any problems. Occasionally, errors in instrumentation or hidden problems may surface during a test resulting in the repair of inoperable or inaccurate equipment. It is best to complete your annual pump testing in conjunction with a service as some repairs that are done may necessitate a new pump test to be done prior to its test expiring.
Non annual pump tests should be conducted when any changes that may affect the performance of a pump have been made. Imagine anything from the front of the engine to the discharge outlet and tailpipe being a change that can effect pump performance. Simple changes to mufflers, exhaust damage, mounting equipment in front of the grille, fuel system work, transmission work, new driveline components, retarder and valve train work, etc. all can affect the rated output of the engine possibly effecting the output of the fire pump. Most commonly engine work may be completed by the engine dealer under warranty, however, the mechanic may be unaware of the need to perform a pump test. This can be problematic for a department that does not have its own mechanics and is unaware of the accepted practices. A modification made by the dealer that may be routine on a highway vehicle may create a problem when the unit is pumping on an incident.
So you have wear, where did it come from? Pumps are very sensitive to debris and mistreatment. Wear can show up as requiring increased engine speed to produce the same rated output at various predetermined pressures. Wear will ultimately progress to the point of a test failure and inability to provide the rated volume and/or pressure. Pump wear can be caused by poor water quality, small debris that can pass through the strainer, missing strainers, cavitation, excessive heat, water hammer and more. Malfunctioning pressure relief devices, transmissions, and plugged strainers can also result in poor performance. A lack of use of an apparatus does not grant the vehicle a waiver for pump testing but often will be a greater reason to test it. Rarely used apparatus can be easily damaged by erosion of components, sediment buildup, or the operator being unfamiliar with the controls. Commonly these vehicles are used to train new operators which ultimately subjects them to unintentional abuse. Reserve and second out apparatus should have the same priority as a front line unit.
A fire pump class is held annually at the Fire Mechanic Workshop and is recommended for any person interested on how to test, maintain, or better understand their fire pump. Performing annual pump testing on apparatus will allow a fleet’s state of readiness to be better known and allow funds to be allotted for repairs before failure necessitates this unexpectedly. Driver confidence in vehicles can be maintained and at least one aspect of the incidents outcome can be known, it should not be made worse by a failure of your pump to perform as the factory intended.
By: Justin Claibourn
Board Member, Fire Mechanic Section