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FIRE HOSE ANNUAL SERVICE TEST
The text on this page is an excerpt from the manual for the
Reliable Fire Products fire hose test machine. When reading, remember that
the procedure below is built around a specific hose testing machine.
Location, Location, Location!
The most important aspect of testing hose with a portable tester is to pick a
location that works to your advantage. The area must be large enough to
lay out all of the hose that is being prepared for test, hose that has been
tested, and the hose which is connected to the machine.
The test machine should be located near a water source and on
reasonably level ground. Avoid placing the tester in an area where water
might pool.
Attention should also be given to how well the entire area
will drain since a lot of water is used in testing.
Hose Stretches
Fire hose is made from very flexible material and stretches easily. When
choosing a location this must be taken into consideration. The pressures
used in testing can increase a length hose as much as 8%. So, if you are
testing at full capacity (300 feet of hose on each discharge outlet) with this
type of hose, as you reach pressure each hose will be fighting for additional
space because the original 1200' of hose is now 1296' long.
This effect will impact your situation in two ways.
First, the hose will take up more room during the test than
during setup. To offset this the operator has to plan in advance for the
additional length.
Secondly, the additional length will require a larger volume
of water to fill it. In the case above, if it is 5" hose, the additional
water required would be 97 gallons after the hose appears to be full. A
good deal of this additional water will be supplied by the pressurized water
source that is connected to the testing equipment. However, the 3 gallon
per minute pump on the tester will have to make up the rest. This will
take time so be patient. Take this time to make your initial visual
inspection of the couplings to check for slippage and leaks. Do not,
however, leave the testing area for any reason. If you must leave, turn
the unit off first.
Air Compresses, Water Does Not
When draining air from the system, take your time to make sure you have as much
of it out as possible. Since air will compress, any remaining air pockets
will drastically increase the time needed to reach testing pressures. But,
even worse, the stored air will expand rapidly should a hose fail and increase
the amount of energy released thus increasing the chances of injury. So,
take your time and get all of the air out of the system prior to starting each
test sequence.
The More the Merrier
When testing hose, it is wise to test several sections at a time. The more
hose that is connected to the machine, the safer it will be should a hose
experience catastrophic failure. If only one or two sections are being
tested, the resulting force from a failure could possibly "whip" the machine.
It is advisable to test at least 200 or more feet of hose at a time.
End Caps
To cap the ends of the hoses being tested, the operator must assure that
whatever is used is able to handle the pressures. Some older caps used to
cover the discharges on fire pumps are not designed to handle the pressures that
can be developed by the test equipment. Use of fire fighting nozzles is
recommended as long as they are fabricated from either brass or aluminum.
Under no circumstances should the common Lexan (plastic) nozzles found on rack
type hose be used.
The best advice for capping hose ends if fire grade nozzles are either not
available or too expensive is to purchase vented caps that are specifically
designed for this type of use.
Look Before You Test
A good visual inspection of hose to be tested can prevent a dangerous situation.
It is not safe to test hose that the operator is certain will fail. A
Section of hose does not have to fail the pressure test in order to be removed
from service. Visual imperfections are valid criteria for failure.
Testing hose that is known to be defective creates a dangerous situation and
should be avoided.
If it is obvious to the naked eye that a section of hose will
fail, testing that hose will also waste the operator's time. The failed
hose will have to be removed from the setup and the test started from the
beginning on all remaining hose. Such hose should be repaired first, if
practical, and then tested to confirm the repairs were done in an acceptable
manner thus saving time. (According to NFPA, sections of fire hose that
are repaired should be tested individually rather than with other hoses.)
The operator should take the necessary time to do a thorough
visual inspection of all hose to be tested and reject the obvious bad lengths.
Testing fire hose is dangerous enough without intentionally
adding to the risk.
The Procedure
Fire hose should be tested as set forth in NFPA Pamphlet 1962, Standard for
the Care, Use, and Service Testing of Fire Hose Including Couplings and Nozzles,
Latest Edition. Copies of this document can be obtained from NFPA by
calling (617)770-3000 or by visiting their website at
http://www.nfpa.org. It is strongly
suggested that anyone testing fire hose obtain a copy and read it thoroughly.
The standards have been produced and honed for years by manufacturers,
firefighters, insuring agencies and other experts on the subject.
During pressurization and when the attained pressure is being
held, all visual inspections should be performed from a distance of about 15
feet.
Do not move or drag any hose once it has reached test
pressure.
Replace gaskets prior to testing fire hose.
Never straddle hose that is pressurized.
- Attach fire hose to be tested (ensure that all connected
hose requires the same test pressure,
- Attach bleeder caps at the free ends of hose,
- Tighten all fittings leaving bleeders open,
- NFPA recommends securing parallel hoses together at the
couplings,
- Connect water source to inlet of tester,
- Slowly open the main inlet valve on the tester,
- Slowly open the individual valve(s) to fill hose with
water,
- As each bleeder begins to pass air-free water, close it
firmly,
- Once all bleeders are closed, allow the setup to sit for
one minute,
- Crack each bleeder slightly to remove remaining air,
- Close all bleeders,
- Close the main inlet valve on the tester, leaving the
individual hose supply valves open,
- Attach hose tester line cord to 110 volt AC outlet,
- Turn switch on,
- Be patient,
- When pressure reaches 50 PSI, adjust the relief valve to
maintain that setting,
- Check for leaks and tighten where necessary,
- Mark the hose at the base of each coupling,
- Clear the area of all non-essential personnel,
- Slowly raise the pressure to the test target point,
- Maintain the test pressure with the pump for a minimum of
one full minute,
- Close all valves,
- Turn pump off,
- The hose must maintain the test pressure for three minutes,
- At the end of test time slowly open bleed valve on
manifold,
- Open individual supply valves and the bleeders on hose
ends,
- Remove caps,
- Disconnect all hose,
- Inspect previous marks,
- Record results.
Remember to thoroughly drain the hose tester before storing.
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