Downloaded from https://www.everyspec.com MIL-STD-81OC 3. PROCEDURES 3.1 Procedure 1. Airborne electronic equipment. Step 1 - Prepare the test item in accordance with General Requirements, 3.2. Prior to starting the test, the internal chamber tempera- ture shall be at standard ambient with uncontrolled humidity. Step 2 - Gradually raise internal chamber temperature to 65° C (149”F) and the relative humidity to 95 +5 -3 percent over a period of 2 hours. Step 3 - Maintain conditions of step 2 for not less than 6 hours. Step 4 - Maintain 85 percent, or greater, relative humidity and reduce internal chamber temperature in 16 hours to 30”C (86”F).
Step 5 - Repeat steps 2, 3, and 4 for a total of 10 cycles (not less than 240 hours). Figure S07.1-1 is an outline of the humidity cycle for this procedure. Step 6 - At the end of the tenth cycle, while still at 30”C (86° F) and 85 percent relative humidity, operate the test item and obtain results in accordance with General Requirements, 3.2. Step 7 - Remove and inspect the test item and obtain results in accord- ance with General Requirements, 3.2. 3..2 Procedure II. Ground and airborne electronic equipment. Step 1 - Prepare the test item in accordance with General Requirements, 3.2, except that initial measurements are taken in step 4.
Step 2 - Dry the test item at S4° C (129”F) for 24 hours. Step 3 - Condition the test item at 23° C (73”F) and 50 *1O percent relative humidity for 24 hours. Step 4 - Take initial measurements in accordance with General Require- ments, 3.2.1 METHOD .507.1 507.1-2