§  2.1509   Environmental and duration tests.

   The environmental and operational tests in § 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 § § 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 § 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 § § 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 § 2.1511 of this part.

   Step (2) Perform the modulation characteristic tests in § 2.1513 of this
   part.

   Step (3) Perform the spectral tests in § 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 § 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 § 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 § 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 § 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 § 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.