FED-STD-228A
4.2 Unless otherwise specified in the detail specification, the specimen shall be subjected to a
temperature of 22 ± 1°C (72° ± 2°F) for a period of 46 ± ¼ hour.
4.3 The contents of the immersion vessel shall be restricted to specimens known to be of the same
composition.
4.4 The specimen shall be free from mechanical damage and shall not be bent or flexed until it has
reached room temperature. Handling and flexing of the specimen shall be reduced to a minimum
necessary in carrying out the test. The ends of the specimen shall be sealed for a distance of about ¼
inch by dipping in melted paraffin, asphalt, or other satisfactory sealing medium. The specimen shall be
dried 46 hours or to a constant weight, whichever is quicker, in a desiccators over anhydrous calcium
chloride at room temperature. The specimen shall then be removed from the desiccators, weighed within
3 minutes to the nearest 10 milligrams, and the weight recorded as W1. Four specimens shall be
prepared and one immersed in each of the solutions specified in 4.1.
4.5 The specimen shall be placed in the immersion vessel and completely surrounded with the solution in
such a manner that the solution can circulate freely around it during the exposure period. At the end of
the exposure period, 4.2, the specimen shall be removed from the solution, rinsed for 15 seconds in
running water, shaken to remove any loose water, and any adhering surface water removed by blotting
lightly with clean absorbent cloth. The specimen shall be weighed within 3 minutes to the nearest 10
milligrams and the weight recorded as W2. The fibrous covering and armor shall be examined for visible
effect of attack by the chemicals and then stripped off.
4.6 The conductors, insulation, and insulation covering shall be weighed to the nearest 10 milligrams and
the weight recorded as W3.
5. RESULTS
5.1 Calculation. The solution absorbed by the specimen shall be calculated as follows:
Absorption, percent = W2-W1 x 100
W2-W3
where:
W1=the weight of the dry specimen, grams
W2=the weight of the specimen after immersion, grams
W3=the weight of the conductors, insulation and insulation covering, grams
5.2 Unless otherwise specified in the detail specification, one specimen from each inspection unit shall
be tested in each solution.
5.3 The absorption of the covering or armor of the inspection unit for the particular solution used shall be
the results obtained from the specimen tested.
5.3.1 When more than one specimen is tested, the absorption of the covering or armor of the inspection
unit for the particular solution shall be the average of the results obtained from the specimens tested.
5.4 Any attack on the fibrous covering or armor of the inspection unit by the solution shall be recorded.
5.5 The absorption of the covering of the inspection unit shall be recorded to the nearest 0.1 percent.
5.6 The immersion solution, exposure period, and exposure temperature shall be recorded.
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