Document-controlled count-range lookup
Documented Oil Particle-Count Code Lookup
Map cumulative 4, 6 and 14 µm(c) channel counts to the published Parker reproduction of the ISO 4406:1999 code table. Optionally compare the three codes with a target taken from a controlled OEM or project source.
Documented count-range result
Implemented interval lookup
select code R only when Lᵣ ≤ N < Uᵣ.
For per-100 mL data: N(per mL)=N(per 100 mL)/100.
Target arithmetic only: within target ⇔ R4≤T4 and R6≤T6 and R14≤T14.
There is no fitted logarithmic formula and no endpoint clamping. Exact lower bounds belong to their row; exact upper bounds belong to the next row. The three cumulative counts must not increase with particle size.
Published table implemented by this page
Parker VEL1948 reproduces the ISO 4406:1999 code levels as codes 1–28 and labels each minimum included and maximum excluded. Its published example 12,545 / 2,750 / 524 particles/mL gives code 21/19/16. The implementation below reproduces every row exactly.
| Codice | Minimum particles/mL (included) | Maximum particles/mL (excluded) |
|---|---|---|
| 1 | 0.01 | 0.02 |
| 2 | 0.02 | 0.04 |
| 3 | 0.04 | 0.08 |
| 4 | 0.08 | 0.16 |
| 5 | 0.16 | 0.32 |
| 6 | 0.32 | 0.64 |
| 7 | 0.64 | 1.3 |
| 8 | 1.3 | 2.5 |
| 9 | 2.5 | 5 |
| 10 | 5 | 10 |
| 11 | 10 | 20 |
| 12 | 20 | 40 |
| 13 | 40 | 80 |
| 14 | 80 | 160 |
| 15 | 160 | 320 |
| 16 | 320 | 640 |
| 17 | 640 | 1300 |
| 18 | 1300 | 2500 |
| 19 | 2500 | 5000 |
| 20 | 5000 | 10000 |
| 21 | 10000 | 20000 |
| 22 | 20000 | 40000 |
| 23 | 40000 | 80000 |
| 24 | 80000 | 160000 |
| 25 | 160000 | 320000 |
| 26 | 320000 | 640000 |
| 27 | 640000 | 1300000 |
| 28 | 1300000 | 2500000 |
Current ISO status and licensed-source boundary
ISO 4406:2021, edition 4, is Published and was confirmed in 2026; it replaced ISO 4406:2017. Its public abstract confirms the coding scope but does not expose the current normative count table. Therefore this page does not claim that the reproduced 1999 rows are the licensed 2021 table. Exact ISO 4406:2021 row confirmation remains NEEDS_LICENSED_SOURCE.
Target and filtration boundary
ISO 12669:2017, edition 1, Published and confirmed in 2023, specifies a method for determining the required cleanliness level of a system. A universal component-name lookup is not substituted for that process. Enter a target only from a controlled OEM, system or project source applicable to the actual pressure, duty, fluid, environment and reliability requirement.
Donaldson’s official filtration guide states that a direct connection between filter beta rating and ISO cleanliness cannot be made without application details, contamination ingression/generation and field monitoring. This page therefore does not select filter micron/beta rating, sampling interval, kidney-loop flow or cleanup time.
Why the former page was changed
The former code treated the table’s lower-bound sequence as upper limits, so most non-boundary counts were assigned one code too dirty; for example, 520 particles/mL was returned as code 17 instead of the published-table code 16. It also capped out-of-table values, accepted impossible non-cumulative triplets, contained presets whose particle counts did not match their labels, and generated universal component targets, filters, sampling intervals and an unsourced two-turnovers-per-code cleanup time.
No maintenance authorization: a code is only a count-range representation. Investigate sample representativeness, flushing state, aeration/water/additive interference, instrument calibration, repeatability and trend. Use the applicable OEM/project cleanliness requirement and a qualified filtration/contamination-control plan before changing filters or operating limits.
