Maximum concentration limits( Particles/m3 of air) for particles equal to and larger than the considered sizes shown below
>= 0.1µm
>= 0.2m
>= 0.3µm
>= 0.5µm
>= 1µm
>= 5.0µm
ISO Class 1
10
2
ISO Class 2
100
24
10
4
ISO Class 3
1000
237
102
35
8
ISO Class 4
10000
2370
1020
352
83
ISO Class 5
100000
23700
10200
3520
832
29
ISO Class 6
1000000
237000
102000
35200
8320
293
ISO Class 7
352000
83200
2930
ISO Class 8
3520000
832000
29300
ISO Class 9
35200000
8320000
293000
Comparison between selected equivalent classes of
Federal Standard 209 and ISO 14644-1
ISO 14644-1 Classes
Class 3
Class 4
Class 5
Class 6
Class 7
Class 8
Federal Standard
Class 1
Class 10
Class 100
Class 1000
Class 10000
Class 100000
EUGGMP 2002 Recommended Limits for Microbial Contamination
Grade
Air Sample cfu/m3
Settle Plates Diam 90 mm cfu/m3
contact Plates Diam 55 mm cfu/m3
Glove Print 5 fingers cfu/glove
A
<1
<1
<1
<1
B
10
5
5
5
C
100
50
25
-
D
200
100
50
-
Note : Grade A and B correspond to with class 100, M 3.5, ISO 5 Grade C correspond to with class 10000, M 5.5, ISO 7 Grade D correspond to with class 100000, M 6.5, ISO 8
