RMF Systems CMS 2 - ISO4406:1999 Cleanliness Code System

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201.028 REV 1 Date of Issue: 18 June 2018
11.4 ISO4406:1999 Cleanliness Code System
Number or Particles per ml
Scale
No.
More than
Up to and
including
2.5M
-
>28
1.3M
2.5M
28
640K
1.3M
27
320K
640K
26
160K
320K
25
80k
160K
24
40k
80k
23
20k
40k
22
10k
20k
21
5000
10k
20
2500
5000
19
1300
2500
18
640
1300
17
320
640
16
160
320
15
80
160
14
40
80
13
20
40
12
10
20
11
5
10
10
2.5
5
9
1.3
2.5
8
0.64
1.3
7
0.32
0.64
6
0.16
0.32
5
0.08
0.16
4
0.04
0.08
3
0.02
0.04
2
0.01
0.02
1
0.0
0.01
0
Figure 11.2 Figure 11.3
The International Standards Organization standard ISO 4406:1999 is the preferred method of quoting the number
of solid contaminant particles in a sample.
The code is constructed from the combination of three scale numbers selected from Figure 11.1.
The first scale number represents the number of particles in a milliliter sample of the fluid that are larger than
4μm(c).
The second number represents the number of particles larger than 6μm(c).
The third represents the number of particles that are larger than 14μm(c).