Iso 4406 Cleanliness Code System - Danfoss Vickers Target-Pro 2 Operation Manual

ISO 4406 Cleanliness
Code System
ISO standard 4406 is the preferred method of counting
solid contaminant particles in a sample. The code is con-
structed from the combination of three scale numbers
selected from the following table.
The first scale number represents how many particles
in a milliliter sample of the fluid are larger than 4 µm(c).
The second number represents how many particles are
larger than 6 µm(c).
The third number represents how many particles are
larger than 14 µm(c).
N U M B E R O F PA R T I C L E S
More Up to
Than Including
2.5M -
1.3M 2.5M
640k 1.3M
320k 640k
160k 320k
80k 160k
40k 80k
20k 40k
10k 20k
5000 10k
2500 5000
1300 2500
640 1300
320 640
160 320
80 160
40 80
20 40
10 20
5 10
2.5 5.0
1.3 2.5
0.64 1.3
0.32 0.64
0.16 0.32
0.08 0.16
0.04 0.08
0.02 0.04
0.01 0.02
0.0 0.01
Table 5: ISO 4406 Allocation of Scale Numbers
1 2 Vickers by Danfoss Target-Pro 2 Analyzer and Sampler Operation Manual V-PP-MC-0002-E
P E R M L . S C A L E N O .
and
> 28
2 8
2 7
2 6
2 5
2 4
2 3
2 2
2 1
2 0
1 9
1 8
1 7
1 6
1 5
1 4
1 3
1 2
1 1
1 0
9
8
7
6
5
4
3
2
1
0
Microscope counting examines the particles differently
from APCs; the code is given with two scale numbers only.
These are at 5 µm and 15 µm, equivalent to the 6 µm(c) and
14 µm(c) of the APCs.
ISO 4406 Cleanliness Code Chart (with 100ml sample volume)
July 2023