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 & 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.
Test specimens are placed in an enclosed chamber (a separate salt mist chamber and controlled humidity chamber are generally used) and exposed to a changing climate that starts with 2 hours exposure to a continuous indirect spray of neutral (pH 6.5 to 7.2) salt water solution, which falls-out on to the specimens at a rate of 1.0 to 2.0ml/80cm²/hour, in a chamber temperature of +15 to +35°C. Depending upon method number, this is followed either by exposure to a high humidity climate of 40°, C93%RH; or air drying at 60 °C, under 30 % RH and then Wetting at 50°C.
The duration of high humidity and number of cycle repeats is variable depending on the test method (1-8)
See IEC 60068-2-52 For breakdown of chamber specification vs test methods