DAVID'S FIRE EQUIPMENT
The following article is a general description of an annual service test on rated fire pumps in automotive fire apparatus and is not intended to be an exact procedure. It is primarily here to introduce you to the procedure and let you know what you are getting into. If you need a more detailed description of exactly how to perform the test and make the calculations, NFPA Pamphlet 1911 or the IFSTA Pumping Apparatus Driver/Operator Handbook will give you all of the information you need.
In a nutshell, an annual pump test is a documented procedure to prove your apparatus can perform at its rated capacity from draft. The chassis drivetrain, pump, pump transmission and associated plumbing are run through a progressive series of tests that are designed to prove the system is in sound working order.
In order to obtain the maximum number of ISO points for pump testing (100 points out of a maximum of 654), your department should have documented tests for at least the last three years. Besides performing and documenting this test on an annual basis it should also be performed on any apparatus that has been repaired or modified in any manner that may affect pumping performance. The test not only assures you that the pump and its associated plumbing can deliver its rated capacity, it also proves that the engine and drive train are up to the task. In addition to ISO points, performing this test on a regular basis will give you peace of mind because you will know that your apparatus is ready to deliver if it needs to.
While NFPA 1911 allows the performance test to be performed from a hydrant it does not promote it. In the Annex it stresses that testing from a hydrant should be used when "no suitable drafting site is available." When testing from a hydrant the residual hydrant pressure must be 20 PSI or greater while flowing rated capacity and that figure must be added to the discharge pressures, e.g. if the residual pressure is 25 PSI then the discharge pressure for the 100 percent capacity test would be 175 PSI (150 test pressure plus 25 residual.) If you choose to test from a hydrant it would be best to check with the water department first. Testing a single 1500 GPM pump will use an absolute minimum of 48,000 gallons of treated water.
Prior to testing is a great time to do periodic maintenance on the apparatus. Changing the engine oil, pump transmission oil, and even servicing the transmission before testing every year will ensure yearly maintenance if your department doesn't already have an established periodic maintenance program.
The annual test does not need to be performed by a third party or outside entity. In fact, performing the test with your own personnel can be a great learning experience. As long as you carefully document the exact layout and all readings, ISO will give your department credit where credit is due. By performing the test in-house you will also have the advantage of being able to answer any questions about the test any ISO representative may have.
From start to finish the actual testing will only take about an hour. Setting up the equipment and tearing it down will probably take longer so it is a good idea to test all units on the same day. If you have a good place to test your trucks you may want to invite the neighbors over to test theirs on the same day.
A good test site is a major consideration. You will need a location where your apparatus will be close enough to drop the hard suction hose and strainer into the water to a depth of about 2 feet (to prevent whirl pools that could cause the pump to lose prime) yet still be high enough from the bottom to prevent picking up silt or other debris. The surface the apparatus will be parked on should be solid and able to support the vehicle when wet. Discharge from the master stream must have somewhere to go without doing any damage (a 1000 GPM pump will move over 150,000 pounds of water during the 20 minute 100 percent test.)
There are also environmental issues that can affect when you can actually perform the test. NFPA would like the temperature to be between 0 and 110 degrees Fahrenheit (most normal people wouldn't want to perform the test outside of those parameters,) the water temperature to be between 35 and 90 degrees Fahrenheit, and the barometric pressure to be a minimum of 29 inches (adjusted to sea level.)
A basic list of equipment needed to properly perform an annual pump test is as follows:
For more information on hose needed for the test, click here.
One way to make the job easier and much more accurate from year to year is to substitute a flow test kit for the pitot gauge and tip assortment. The test kit will give a continuous reading to your personnel, keep them drier, and give much more accurate and repeatable results. The test kit setup will place the pitot inlet in the exact right location and keep it there.
Before beginning any pump test it is a good idea to perform normal periodic maintenance on the rig to be tested. If the unit is not close to requiring periodic maintenance, check and correct all fluid levels, primer oil level (if applicable,) and make sure the fuel tank is topped off.
The test sequence should ideally be performed at a 10' lift as measured from the surface of the water to the center of the main suction inlet. If you cannot find a location where a 10' lift is achievable there is a formula in the reference materials that can be used to correct gauge readings to accommodate you. Calculations will also be required to determine "the corrected net pump pressure." What all this means is that you won't actually be reading 150 psi on the master gauge when running the 150 psi pump test. You will be reading a pressure which is corrected to reflect the amount of vacuum in the suction and the actual lift. Thus, while a 10' lift is the ideal, any amount of lift will do.
An annual pump test is actually a series of timed tests as follows:
The individual tests are performed in that order and if the unit should fail any single test the entire series must be repeated after repairs. This test is different from the certification test that is performed by a third party for apparatus manufacturers which is much longer and much more rigorous.
The most important part of the test is recording the results. The person testing the apparatus should record all pertinent readings at the start of each test and every 5 minutes during the test. Here is an example (Microsoft Excel spreadsheet) of a form that can be used and/or modified to meet your needs. The more information that is documented, the easier it will be for others to perform tests in the future. Providing the paperwork to ISO is certainly a concern however, the history provided will also provide a means to evaluate the performance of your apparatus. Should a piece of equipment show a slow and gradual decline in performance you will get a good idea of when it will need to be replaced.
It is interesting to note that of the total 654 points ISO CAN award for an engine company, all are based on equipment carried except pump testing (100) and hose testing (50). Those departments that think they can get by on equipment carried alone will automatically loose 150 points. So, even if your budget is tight, once you have the equipment needed to perform a pump test you can ensure your department gets these big point items every time. As a bonus, pump testing can be used as training too.
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David's Fire Equipment