Worldwide Standard

Worldwide Standard

Cleanliness

The cleanroom classification standards FS 209E and ISO 14644-1 require specific particle count measurements and calculations to classify the cleanliness level of a cleanroom or clean area.

ISO 14644-1

Maximum concentration limits (particles/m3 )
Classification Number (N) 0.1μm 0.2μm 0.3μm 0.5μm 1.0μm 5.0μm
ISO Class 1 10 2
ISO Class 2 100 24 10 4
ISO Class 3 1,000 237 102 35.2 8
ISO Class 4 10,000 2,370 1,020 352 83
ISO Class 5 100,000 23,700 10,200 3,520 832 29
ISO Class 6 1,000,000 237,000 102,000 35,200 83,200 293
ISO Class 7 352,000 832,000 2,930
ISO Class 8 35,200,000 8,320,000 29,300
ISO Class 9 293,000

Federal Standard 209E Airborne Particulate Cleanliness Classes

ICR Cleanliness Diameter for Airborne Particle
0.1μm 0.2μm 0.3μm 0.5μm 0.5μm
Volume Units Volume Units Volume Units Volume Units Volume Units
SI Class (m3) (ft3) (m3) (ft3) (m3) (ft3) (m3) (ft3) (m3) (ft3)
M1   350 9.91 75.7 2.14 30.9 0.875 10.0 0.283
M1.5 1 1240 35.0 265 7.50 106 3.00 35.3 1.00
M2   3,500 99.1 757 21.4 309 8.75 100 2.83
M2.5 10 12,400 350 2,650 75.0 1,060 30.0 353 10.0
M3   35,000 991 7,570 214 3,090 87.5 1,000 28.3
M3.5 100 26,500 750 10.600 300 3,530 100
M4   75,700 2,140 30,900 875 10,000 283
M4.5 1000 35,300 1,000 247 7.00
M5   100,000 2,830 618 17.5
M5.5 10,000 353,000 10,000 2,470 70.0
M6   1,000,000 28,300 6,180 175
M6.5 100,000 3,530,000 100,00 24,700 700
M7   10,000,000 283,000 61,800 1,750

JIS B 9920

Class Maximum concentration limits (particles/m3 )
0.1μm 0.2μm 0.3μm 0.5μm 1μm 05μm
Class1 10 2
Class2 100 24 10 4
Class3 100 237 102 35 8
Class4 10,000 2,370 1,020 352 83
Class5 100,000 23,700 10,200 3,520 832 29
Class6 237,000 102,000 35,200 8,320 293
Class7 352,000 83,200 2,930
Class8 3,520,000 832,000 29,300
Class9 35,200,000 8,320,000 293,000

Worldwide Standard comparison

Worldwide Standard Class
ISO 14644-1 ISO 3 ISO 4 ISO 5 ISO 6 ISO 7 ISO 8
FS 209E Class 1 Class 10 Class 100 Class 1000 Class 10000 Class 100000
FS 209E(SI) M1.5 M2.5 M3.5 M4.5 M5.5 M6.5
JIS B 9920 Class 3 Class 4 Class 5 Class 6 Class 7 Class 8
Britain BS 5295 C D E/F G/H J K
Germany VD I.2083 1C 2 3 4 5 6
Australia AS 1386 0.035 0.35 3.5 35 350 3500
France AFNOR X44101 4,000 4,000 4,000,000
Grade A/B C