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.
ASTM G85 annex A5
Dilute electrolyte cyclic fog /dry test
Can be used to test the relative resistance to corrosion paints on steel, when exposed to an changing climate of dilute salt spray at ambient temperature, followed by air drying at an elevated temperature.
Test specimens are placed in an enclosed chamber, and exposed to a changing climate that comprises of the following 2 part repeating cycle. 1.0 hours exposure to a continuous indirect spray of dilute acidified (pH 5.0 to 5.4) salt water solution, which falls-out on to the specimens at a rate of 1.0 to 2.0ml/80cm²/hour, in an ambient chamber temperature (21 to 27C). This is followed by 1.0 hours exposure to an air drying (purge) climate, in a chamber temperature of +35C. The number of cycle repeats and therefore the test duration is variable.
This test is also referred to as a PROHESION test.
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