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  Sec.  Sec. 2.1511, 2.1513 and 2.1515 of
   this part. The test unit is not to be adjusted, nor 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  °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  °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  °C ( ±2  °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  °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  Sec.  Sec. 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 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  °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  °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 ° to +55  °C at intervals of not more
   than 10  °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  °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   °C  is the reference for determining the frequency
   tolerance.

   Step  (4)  Increase the temperature in the chamber to +55  °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  °C maximum increments
   until −20  °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 ° to
   +55  °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.