The absolute rating of a filter element refers to which characteristic?

The absolute rating of a filter element specifically relates to the largest hole size within the filter media. This measurement indicates the minimum size of particles that the filter is guaranteed to capture from the fluid passing through it. An absolute-rated filter will effectively block all particles equal to or larger than its specified hole size, ensuring that contaminants above this threshold are not allowed to pass through. This is critical in applications where maintaining fluid purity is essential, as it ensures consistent performance and protection of downstream equipment.

In contrast, other characteristics like flow rate, particle size, and filter material type do not define the filter’s ability to block particles based on size. Flow rate pertains to how much fluid can pass through the filter in a given time but does not relate to particle size exclusion. The term “particle size” can reference a range or a nominal rating, which does not guarantee the same assured retention as the absolute rating. Similarly, the filter material type refers to the composition of the filter and its overall filtration capabilities, but it does not specify the exact hole size in the media.