ISO 14644-1 Cleanroom Standards

US FED STD 209E Cleanroom Standards
Class Maximum Particles/ft3 ISO
Equivalent
≥0.1µm ≥0.2µm ≥0.3µm ≥0.5µm ≥5µm
1 35 7.5 3 1 0.007 ISO 3
10 350 75 30 10 0.07 ISO 4
100 3,500 750 300 100 0.7 ISO 5
1,000 35,000 7,500 3,000 1,000 7 ISO 6
10,000 350,000 75,000 30,000 10,000 70 ISO 7
100,000 3.5 x 106 750,000 300,000 100,000 700 ISO 8
US FED STD 209E was officially cancelled by the General Services Administration of the US Dept. of Commerce November 29, 2001, but is still widely used.
ISO 14644-1 Cleanroom Standards
Class Maximum Particles/m3 FED STD 209E
Equivalent
≥0.1µm ≥0.2µm ≥0.3µm ≥0.5µm ≥1µm ≥5µm
ISO 1 10 2.37 1.02 0.35 0.083 0.0029
ISO 2 100 23.7 10.2 3.5 0.83 0.029
ISO 3 1,000 237 102 35 8.3 0.029 Class 1
ISO 4 10,000 2,370 1,020 352 83 2.9 Class 10
ISO 5 100,000 23,700 10,200 3,520 832 29 Class 100
ISO 6 1.0 x 10 237,000 102,000 35,200 8,320 293 Class 1,000
ISO 7 1.0 x 107 2.37 x 106 1,020,000 352,000 83,200 2,930 Class 10,000
ISO 8 1.0 x 108 2.37 x 107 1.02 x 107 3,520,000 832,000 29,300 Class 100,000
ISO 9 1.0 x 106 2.37 x 108 1.02 x 108 35,200,000 8,320,000 293,000 Room Air
BS 5295 Cleanroom Standards
Class ≥0.5µm ≥1µm ≥5µm ≥10µm ≥25µm
Class 1 3,000 0 0 0
Class 2 300,000 2,000 30
Class 3 1,000,000 20,000 4,000 300
Class 4 200,000 40,000 4,000
BS 5295 Class 1 also requires that the greatest particle present in any sample does not exceed 5µm.
GMP EU Classification
Class Maximum Particles/m3
At Rest At Rest In Operation In Operation
0.5µm 5µm 0.5µm 5µm
Class A 3,520 20 3,500 20
Class B 3,520 29 352,000 2,900
Class C 352,000 2,900 3,520,000 29,000
Class D 3,520,000 29,000 N/A N/A