SCHEMATICCURRENT · v1.0.0DIAG-BETA-RATIO

Beta Ratio Measurement — Upstream / Downstream Particle Count

Illustrates the fundamental principle of the Beta ratio (filtration ratio) as defined in ISO 16889. Upstream particles of all sizes enter the filter element; only those below the rated efficiency cut-off pass through to the downstream side. The ratio of upstream to downstream particle counts at a given size defines the Beta ratio, which directly quantifies filtration efficiency.

Left zone shows upstream contaminated fluid with many particles of varying sizes (large orange circles, medium particles, fine particles). Central zone is the filter element shown as a hatched rectangle. Right zone shows downstream clean fluid with only a few fine particles that passed through. Formula β = Nᵤ/Nd and efficiency E(%) = (1 − 1/β) × 100 are shown at bottom.

GOVERNING STANDARDS

ISO 16889

ISO 11171

ELIMFILTERS TECHNOLOGIES

NANOFORCE™

SYNTRAX™

APPLICABLE SYSTEMS

Hydraulic Protection

Lubrication Protection

Fuel Cleanliness Protection

REVISION METADATA

Versionv1.0.0

Statuscurrent

Last Reviewed2026-07-08

Next Review2027-07-08