The Kesternich Test in accordance with ISO 3231 (or ASTM G 87) is a condensation cycle test in an acidic environment. In the closed container, in which the test samples are exposed, during the first 8 hours an atmosphere of 100 % relative humidity at a temperature of 40 °C is maintained. At the start of these 8 hours a certain amount of SO2 (sulfur dioxide) is added. After the 8 hour, period the cabinet is vented and the heating is switched off. The samples are conditioned for the next 16 hours at room temperature and ambient relative humidity. After this the test cycle is repeated for the next 24 hours. This continues until the number of cycles required. This can vary from 2 to 50 or more.
The Kesternich Test is mentioned in various standards and specifications, including Qualicoat for coated aluminum, Qualisteelcoat, specifications for bolts and screws, but also in various specifications of coil coating systems and coatings for cars and traffic objects.
In the Kesternich Test also modifications are carried out such as the use of other gases (for example CO2 or NH3) and maintaining other temperatures.