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|  MIL-I-85889(AS)
4.5.2 Environmental treatments.
4.5.2.1 Transportation vibration. The igniter shall be subjected to a vibration environment in accordance with
Category 1- Basic Transportation, Method 514.3 of MIL-STD-810 Test levels will be in accordance with figures 514.31
through 514.33 of MIL-STD-810. Maximum expected transportation distance is 3000 miles, and the packaged igniter
is to be treated as secured cargo. During vibration testing, the packaged igniter shall be contained in a temperature
controlled chamber maintained at the specified temperature.
4.5.2.2 Thermal shock. The igniter shall beheld in a conditioning chamber at the storage temperature upper
limit (STUL) for the requisite thermal stabilization period. The igniter shall then be moved to another chamber at
the storage temperature lower limit (STLL) within 5 minutes. The igniter shall be held in the low temperature chamber
for the requisite thermal stabilization period. The hot-to-cold cycle shall be repeated a total of 3 times with no more
than 5 minutes between transfers. (For ease of test, the length of the hot and cold dwell periods may be increased
so that the total cycle duration is 24 hours.) The igniter shall then be removed and allowed to return to ambient
temperature
4.5.2.3 High temperature storage. The igniter shall be placed in a conditioning chamber maintained at the
STUL for a period of 6 weeks.
4.5.2.4 Altitude. The igniter shall be subjected to a low pressure environment in accordance with Procedure
I- Storage, Method 500.2 of MIL-STD-810. The packaged igniter shall be held at an equivalent of 15,000 feet attitude
for a minimum of 1 hour.
4.5.2.5 Rain. The igniter shall be exposed to a rainfall environment in accordance with Procedure I - Blowing
Rain, Method 5062 of MIL-STD-810 The igniter shall be conditioned to a temperature 18 F greater than the rain
temperature prior to testing. Rainfall rate shall be 4 inches per hour and wind velocity shall be 40 miles per hour.
Test duration shall be 30 minutes.
4.5.2.6 Salt fog. The igniter shall be subjected to an aqueous salt atmosphere in accordance with Procedure
I - Aggravated Screening, Method 509.2 of MIL-STD-810 Test duration shall be 48 hours. After exposure, the test
unit shall be allowed to dry for 48 hours under ambient conditions.
4.5.2.7 Sand and dust. The igniter shall be subjected to an airborne dust environment in accordance with
Procedure i - Blowing Dust, Method 510.2 of MIL-STD-810. Air velocity shall beat the limits of the test apparatus
or 1750 feet per minute whichever is less, but in no case less than 300 feet per minute. Test duration shall be 24 hours.
4.5.2.6 Six-foot drop. The igniter shall be conditioned to the specified operating temperature limit and dropped
onto a 2-inch thick steel plate (minimum Brinell hardness of 207) embedded in not less than 2 feet of concrete.
Six feet, as measured from the lowest point of the test article, shall be the drop height. In each group of four test
items, the drop attitudes shall be two horizontal and one each aft end down and forward end down.
4.5.2.9 Fungus. The igniter shall be subjected to a fungi-promoting environment in accordance with Method
508.3 of MIL-STD-810. The test duration shall be 28 days.
4.5.2.10 Humidity. The igniter shall be subjected to a warm, humid atmosphere in accordance with cycle 5,
Procedure II, Method 507.2 of MIL-STD-810. The test duration shall be 30 days.
45.2.11 Ballistic performance static firing. The igniter, in its bare condition (see 6.3.1.3), shall be conditioned
to the specified temperature. Within 10 minutes after removal from the conditioning chamber, the igniter shall be
attached to a test fixture and static fired. The ignition current shall replicate that of the end use application Post-
firing inspection shall be performed in accordance with the marginality of success evaluation plan (see 4.2.3.4)
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