AS 2331.3.1 Methods of test for metallic and related coatings Corrosion and related property tests- Neutral salt spray test is a method for the neutral salt spray (NSS) test for the assessment of corrosion resistance of inorganic and organic coatings on metallic substrates.
Coatings are exposed to a corrosive atmosphere under controlled conditions for different durations. Resistance to corrosive attack is used to assess the quality of the coating against the conditions of the test. All chemicals used are of a recognized analytical reagent grade.
The number and type of test pieces or test specimens, and their shape and dimensions, are selected in accordance with the specification covering the product items under test.
Test pieces are thoroughly cleaned before testing, and placed in the cabinet so that they are not in the direct line of travel of sprayed test solution. The recommended periods of exposure are 2 h, 6 h, 24 h, 48 h, 72 h, 96 h, 168 h, 240 h, 336 h, 480 h, 720 h or 1000 h.