CHARTCURRENT · v1.0.0DIAG-ISO4406-CLEANLINESS

ISO 4406 Fluid Cleanliness Code Scale

Provides a visual reference for interpreting ISO 4406 cleanliness codes. The three-number code (e.g. 17/15/12) represents particle count ranges at ≥4µm, ≥6µm, and ≥14µm channels respectively. Each code increment represents a doubling of particle count. Target cleanliness levels for common hydraulic components are overlaid to show where a given ISO code falls relative to component sensitivity.

Chart with ISO 4406 code number on X-axis (6 to 24) and particle count per mL on Y-axis (logarithmic, 0.32 to 20,000). Three lines represent the ≥4µm(c), ≥6µm(c), and ≥14µm(c) particle size channels per ISO 11171. Horizontal bands show target cleanliness for servo valves (≤14/12/10), proportional valves (≤17/15/12), and gear pumps (≤19/17/14).

GOVERNING STANDARDS

ISO 4406

ISO 11171

ELIMFILTERS TECHNOLOGIES

NANOFORCE™

SYNTRAX™

APPLICABLE SYSTEMS

Hydraulic Protection

Lubrication Protection

REVISION METADATA

Versionv1.0.0

Statuscurrent

Last Reviewed2026-07-08

Next Review2027-07-08