ISO 9022-4:2014 specifies the methods relating to the environmental tests of optical instruments including additional assemblies from other fields (e.g. mechanical, chemical, and electronic devices), under equivalent conditions, for their ability to resist the influence of salt mist.
Exposure to salt mist mainly results in the corrosion of metals. Effects might also occur by way of clogging or binding of moving parts.
The purpose of the testing is to assess, as early as possible, the ability of the instrument, and particularly of the surfaces and protective coatings of the instrument, to resist the effects of a salt atmosphere.
Normally, representative samples or complete small units are used for testing. Complete large instruments or assemblies are only tested as specified in this part of ISO 9022 in exceptional cases.