Cleanliness Classes - Brief Overview; Cleanliness Class - Iso 4406:1999 - HYDAC FILTER SYSTEMS ContaminationSensor CS 1939 Series Operating And Maintenance Instructions Manual

Cleanliness classes - brief overview

Cleanliness class - ISO 4406:1999

In ISO 4406:1999, particle counts are determined cumulatively, i.e. > 4 µm
>6 µm and >14 µm
(c)
membrane or automatically using particle counters) and allocated to
measurement references.
The goal of allocating particle counts to references is to facilitate the
assessment of fluid cleanliness ratings.
In 1999 the "old" ISO 4406:1987 was revised and the size ranges of the
particle sizes undergoing analysis redefined. The counting method and
calibration were also changed.
This is important for the user in his everyday work: even though the
measurement references of the particles undergoing analysis have changed,
the cleanliness code will change only in individual cases. When drafting the
"new" ISO 4406:1999 it was ensured that not all the existing cleanliness
provisions for systems had to be changed.
Table - ISO 4406
Assignment of particle counts to cleanliness classes:
Particle count / 100 ml
Class More than Up to (and
0 0
1
1
2 2
3 4
4
8
5 16
6 32
7 64
8
130
9 250
10 500
11 1,000
12 2,000
13 4,000
14 8,000
ContaminationSensor CS 1939
BeWa CS1939 3978342c V100 en-us 2019-10-08.docx
(manually by filtering the fluid through an analysis
(c)
including)
1
2
4
8
16
32
64
130
250
500
1,000
2,000
4,000
8,000
16,000
en
Particle count / 100 ml
Class More than Up to (and
15 16,000
16
32,000
17 64,000
18 130,000
19
250,000
20 500,000
21 1,000,000
22 2,000,000
23
4,000,000
24 8,000,000
25 16,000,000
26 32,000,000
27 64,000,000
28 130,000,000
Glossary
,
(c)
including)
32,000
64,000
130,000
250,000
500,000
1,000,000
2,000,000
4,000,000
8,000,000
16,000,000
32,000,000
64,000,000
130,000,000
250,000,000
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2019-10-08