Are these reported micron ratings based on single pass or multipass?

[twX]

Can anybody explain the micron ratings based on the lastest ISO 4548-12 (2017) standard? Are the reported micron ratings from multipass tests? I see some filters using this test methodology, and reporting a 20 micron rating at 99% (Bosch), or 95.7% (Fram Extraguard). I'm using a Baldwin 7167 rated 40 micron at 98.7% and 18 micron at 50%, which seems much worse. I am assuming that the Baldwin is tested with a single pass, whereas the other filters tested to the latest ISO 4548-12 are reporting multipass results. Is this the case? Is there any way to compare these results?

Also, if anybody has access to that latest ISO standard in PDF, I'd appreciate help in finding a copy.

 

[benjy]

rarely do you get detailed ratings on oil filters, try calling the manufacturer, good luck!!

 

[wdn]

WIX I am using is Laboratory Test Performance per ISO 454812: 18 Grams Dirt, 99% Efficient At 23 Microns

 

[ZeeOSix]

Can anybody explain the micron ratings based on the lastest ISO 4548-12 (2017) standard? Are the reported micron ratings from multipass tests? I see some filters using this test methodology, and reporting a 20 micron rating at 99% (Bosch), or 95.7% (Fram Extraguard). I'm using a Baldwin 7167 rated 40 micron at 98.7% and 18 micron at 50%, which seems much worse. I am assuming that the Baldwin is tested with a single pass, whereas the other filters tested to the latest ISO 4548-12 are reporting multipass results. Is this the case? Is there any way to compare these results?

Also, if anybody has access to that latest ISO standard in PDF, I'd appreciate help in finding a copy.

ISO 4548-12 is a multi-pass test. It's basically like many single pass tests being ran over and over while the filter loads up and gets to a determined point of ending the test. A single pass test is done with one pass on a few filter, so you can't see how the efficiency behaves as it gets more and more loaded.

Why do you think Baldwin is using a single pass test ... do they reference an efficiency test procedure number of any kind?

 

[RamFan]

Baldwin is simply a less efficient filter.

 

[DGXR]

Be honest, how many thought of this movie when we read the thread topic?
The Fifth Element