Sec. 2.1509  Environmental and duration tests.

    The environmental and operational tests in Sec. 2.1509 (a) through 
(e) are to be conducted on a single test unit in the order given below. 
This sequence of tests also includes the electrical tests in 
Secs. 2.1511, 2.1513 and 2.1515 of this part. The test unit is not to be 
adjusted, nor

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is the battery to be replaced during these tests, and a log of battery 
on-time should be maintained. The above tests are to be performed on the 
same test unit. The tests in Sec. 2.1509 (f) through (i) may be run in 
any sequence or may be performed on separate test units.
    (a) Vibration test.

    Step (1) Secure the EPIRB to the vibration table. The EPIRB is not 
to be operated and should not activate while being vibrated.
    Step (2) Subject the EPIRB to sinusoidal motion parallel to one of 
the three major orthogonal axes under the following conditions:

                                                                        
         A. Frequency (Hz)                   Peak amplitude (mm)        
                                                                        
4-10..............................                            2.5       
10-15.............................                            0.8       
15-25.............................                            0.4       
25-33.............................                            0.2       
                                                                        

    B. The frequency is to be changed either linearly or logarithmically 
with time between 4 Hz and 33 Hz such that a complete cycle (4 Hz to 33 
Hz to 4 Hz) takes approximately 5 minutes.
    C. The EPIRB is to be vibrated for at least 30 minutes or six 
complete cycles.
    Step (3) Remount the EPIRB, if necessary, and repeat step 2 for each 
of the other two major orthogonal axes.
    Step (4) Upon completion of the test, perform an exterior mechanical 
inspection and verify operation by turning the unit on and observing the 
RF power indicator on the unit or monitoring the transmission with a 
receiver. Record test results.

    (b) Thermal shock tests. These tests are to be performed on EPIRBs 
which are required or intended to float.
    (1) Low temperature thermal shock test.

    Step (1) Place the EPIRB in a temperature chamber for at least 3 
hours at -20  deg.C or colder. The EPIRB is not to be operated while 
being cooled.
    Step (2) Immediately place the EPIRB in water that has been 
maintained at +10  deg.C or warmer.
    Step (3) After 15 minutes, perform as exterior mechanical inspection 
and verify operation by turning the unit on and observing the RF power 
indicator on the unit or monitoring the transmission with a receiver. 
Record test results.

    (2) High temperature thermal shock test.

    Step (1) Place the EPIRB in a temperature chamber for at least 3 
hours at +55 degrees C or warmer. The EPIRB is not to be operated while 
being heated.
    Step (2) Immediately float the EPIRB in water that is maintained at 
+25 degrees C or colder.
    Step (3) After 15 minutes, perform an exterior mechanical inspection 
and verify operation by turning the unit on and observing the RF power 
indicator on the unit or monitoring the transmission with a receiver. 
Record test results.

    (c) Salt fog test.

    Step (1) Place the EPIRB in a salt fog chamber for a period of at 
least 2 hours at a temperature of 35  deg.C (#2  deg.C) 
before exposing it to salt fog. The EPIRB is to be turned off during 
this test.
    Step (2) With the chamber temperature maintained at 35  deg.C, 
introduce salt fog at the saturation point for 48 hours. The salt fog is 
to be prepared from a 5% (#1%) salt (sodium chloride 
solution. For detailed guidance on the preparation of the solution and 
the apparatus for generating salt fog, refer to MIL-STD-810D (19 July 
1983), method 509.2.
    Step (3) Upon completion of the salt fog exposure, the EPIRB is to 
be airdried at room temperature for 12 hours and operation verified by 
turning the unit on and observing the RF power indicator on the unit or 
monitoring the transmission with a receiver. Record observations.

    (d) Drop test. This test is to be performed on EPIRB which are 
required or intended to float.

    Step (1) Turn the EPIRB on, log the time and drop it three times 
into water from a height of 20 meters. The water is to be deep enough so 
that the EPIRB does not touch bottom when dropped. Each drop should be 
initiated from a different orientation as follows: antenna vertical up; 
antenna vertical down; antenna horizontal.
    Step (2) Upon completion of the drop test, an exterior mechanical 
inspection is to be performed and operation verified by observing the RF 
power indicator on the unit or monitoring the transmission with a 
receiver. Record observations. Turn the test unit off and log the total 
on-time.

    (e) Forty-eight hour operational test. This test includes the 
battery life test and all the electrical tests given in Secs. 2.1511, 
2.1513 and 2.1515 of this part, at various temperatures. The tests are 
to be performed on the same EPIRB in the sequence specified herein. Be 
sure to record the on-time of the unit during each test. No more than 8 
hours of total on-time is permitted before commencing step 4. When 
operating the EPIRB in the environmental chamber, a non-radiating load 
may be substituted for the antenna provided it is

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electrically equivalent to the standard antenna and does not reduce the 
battery current drain.

    Step (1) Perform the radiated emissions test in Sec. 2.1511 of this 
part.
    Step (2) Perform the modulation characteristic tests in Sec. 2.1513 
of this part.
    Step (3) Perform the spectral tests in Sec. 2.1515 of this part.
    Step (4) With the EPIRB off, place unit in an environmental chamber 
at a temperature of -20  deg.C for at least 2 hours.
    Step (5) With the EPIRB in the chamber, repeat the carrier frequency 
test in Sec. 2.1515(d) of this part. (Leave the EPIRB turned on.)
    Step (6) Near the end of 48 hours of total on-time for the EPIRB, 
repeat the carrier frequency test in Sec. 2.1515(d) of this part.
    Step (7) At the end of 48 hours of total on-time, remove EPIRB from 
the chamber and immediately repeat the PERP test for the fundamental 
emissions in Sec. 2.1511(c) of this part. The unit should be maintained 
at -20  deg.C to the extent possible for this test.

    (f) Float free and activation test. This test is required only for 
Class A EPIRBs.

    Step (1) The EPIRB is to be installed in the automatic release 
mechanism and the assembly is to be mounted on a fixture simulating a 
deck or bulkhead as per manufacturer' installation instructions.
    Step (2) Submerge the fixture in water in its normal mounted 
orientation. The EPIRB must float free before reaching a depth of 4 
meters and should automatically activate. Activation is to be verified 
by observing the RF power indicator on the unit or monitoring the 
transmission with a receiver.


If the EPIRB is equipped with an automatically deployable antenna, the 
antenna must properly deploy during each immersion. Record observations.
    (g) Stability and buoyancy test. This test is to be performed on 
EPIRBs which are required or intended to float. This test is to be 
conducted in fresh water.

    Step (1) With the antenna deployed in its normal operating position, 
submerge the EPIRB in a horizontal position just below the surface of 
the water.
    Step (2) Release the EPIRB and observe the amount of time required 
for it to come to an upright position. It must reach its upright 
position within one second from each position.


The EPIRB must have a reserve buoyancy of at least 5% of its gross 
weight. It must also float upright in calm water with the base of the 
antenna a minimum of 5 cm above the water. Record the time required for 
the test unit to right itself.
    (h) Temperature/frequency test. The frequency stability shall be 
measured over an ambient temperature from -20 deg. to +55  deg.C at 
intervals of not more than 10  deg.C. A period of time sufficient to 
stabilize all of the components of the oscillator circuit at each 
temperture level shall be allowed prior to frequency measurement.

    Step (1) Place the EPIRB in the environmental test chamber.
    Step (2) Adjust the temperature in the chamber to +20  deg.C and 
allow sufficient time for the oscillator to stabilize at that 
temperature.
    Step (3) Measure the carrier frequency in accordance with the 
procedure in Sec. 2.1515(d) of this part. Record the carrier frequency 
in Hertz. The carrier frequency at +20  deg.C is the reference for 
determining the frequency tolerance.
    Step (4) Increase the temperature in the chamber to +55  deg.C and 
allow sufficient time for the oscillator to stabilize at that 
temperature. Measure the carrier frequency using the procedure in 
Sec. 2.1515(d) of this part.
    Step (5) Reduce the temperature in the chamber in 10  deg.C maximum 
increments until -20  deg.C is reached. At each new temperature, allow 
sufficient time for the oscillator to stabilize at that temperature. 
Measure the temperature and frequency in each case and plot the 
frequency vs temperature from -20 deg. to +55  deg.C.

    (i) Leakage and immersion test.

    Step (1) Completely submerge the EPIRB in water for 48 hours. The 
EPIRB is to be turned off during this test.
    Step (2) Remove the EPIRB from the water and wipe dry.
    Step (3) Verify operation by briefly turning the EPIRB on and 
observing the RF power indicator on the unit or monitoring the 
transmission with a receiver.
    Step (4) Open the EPIRB for examination. There is to be no water 
inside the unit. Record observations.