This part of ISO 9022 specifies methods for the test-ing of optical instruments and instruments containing optical components, under equivalent conditions, for their ability to resist the influence of blowing dust.
The purpose of testing is to investigate to what extent the optical, thermal, mechanical, chemical and elec-trical performance characteristics of the specimen are affected by blowing dust, especially with a view to malfunctions of moving parts (such as sliding sur-faces, bearings, contacts, operating controls, gears) or unacceptable wear of surfaces.
This test is not intended to determine the wear re-sistance to coarse dust.