The multi-pass filter performance test is internationally recognized as the most reliable means to obtain consistent and repeatable information on a filter's ability to control specific-sized particles.

The multi-pass 'beta' (ß) test challenges the filter in a similar manner as an operating system would!

Here's how
Fresh contaminant is introduced in a slurry form into the test reservoir, mixed with the fluid in the reservoir, and pumped through the test filter
Contaminant not captured by the filter is returned to the reservoir for another pass through the filter (thus the name "multi-pass")
Upstream and downstream fluid samples are analyzed to determine their respective particle counts
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