Vocabulary A-Z of component cleanliness of ISO 16232

abrasive particle

particle liable to change the surface finish

active component

component which may set the fluid in motion or be activated by the fluid during operation, for example pump, cylinder, distributor, injector, valve regulator


two or more particles which are in intimate contact and cannot be separated by gentle stirring and the small shear forces thus generated


continuous and/or irregular movement of a component

ambient contamination

contaminants that are found in the atmosphere surrounding the component

Automatic Particle Counter

automatic light extinction particle counter APC counter that works on the light extinction principle