The test standard summaries are for general guidance only. Though believed to be accurate at the time of writing, this may change over time. So this information should not be used as a substitute for referring to a complete test standard, at an appropriate revision level.
Note: the terms salt spray, salt mist and salt fog are all in wide spread use within corrosion test standards. In this context they can be considered to be equivalent and interchangeable terms.
MIL-STD-750 method 1046
Method 1046.3: Salt Spray (Corrosion)
This MIL standard had been revised and re-issued several times, with each issue being designated a new sequential suffix letter, which appears after the main standard number. With each revision the method number specific to this particular test may have changed, but the method itself is generally as follows:
Test specimens are placed in an enclosed chamber and exposed to a continuous indirect spray of salt water solution, which falls-out on to the specimens at a rate that deposits 0.5 to 3.0/80cm²/hour based on an average run of at least 16 hours, in a chamber temperature of +35°C +1.1°C, –1.7°C. This climate is maintained under constant steady state conditions. The test duration is either 48 hours or 96 hours.
Note that a 24hr drying period at 40°C is required at the completion of the test.
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