This test: - is intended to provide accelerated means to assess the corrosive effects of atmospheres polluted with sulphur dioxide on contacts and connections; - is particularly suitable for giving information on a comparative basis; - is not suitable as a general corrosion test, i.e. it may not predict the behaviour of contacts and connections in industrial atmospheres. The object of this test is: a) to determine the influende of atmospheres containing sulphur dioxide on the contact properties of precious metal or precious metal-covered contacts and connections, excluding contacts consisting of silver and some of its alloys; b) to check solderless connections with regard to their tightness or effectiveness. In all tests, the major criterion of performance will be the change on coontact resistance caused by exposure to the sulphur dioxide test atmosphere.