ISO 16889:2008 describes a multi-pass filtration performance test with continuous contaminant injection for hydraulic fluid power filter elements; a procedure for determining the contaminant capacity, particulate removal and differential pressure characteristics; a test currently applicable to hydraulic fluid power filter elements that exhibit an average filtration ratio greater than or equal to 75 for particle sizes less than or equal to 25 µm(c), and a final reservoir gravimetric level of less than 200 mg/L; and a test using ISO medium test dust contaminant and a test fluid.

ISO 16889:2008 is intended to provide a test procedure that yields reproducible test data for appraising the filtration performance of a hydraulic fluid power filter element without influence of electrostatic charge.

ISO 16889:2008 applies to three test conditions: test condition 1, conducted with a base upstream gravimetric level of 3 mg/L; test condition 2, conducted with a base upstream gravimetric level of 10 mg/L; and test condition 3, conducted with a base upstream gravimetric level of 15 mg/L.