Maximum permitted number of particles/m3 equal
or above
at rest
in operation
0.5µm
5.0µm
0.5µm
5.0µm
A
3,520
29
3,500
29
B
35,200
293
3,52,000
2,930
C
3,52,000
2,930
35,20,000
29,300
D
35,20,000
29,300
not defined
not defined
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
