TECHNICAL BULLETIN: Comparison of Cleanroom Standards
Date: 12th October 2011
ISO 14644-1 counts mer m3 per size and greater
| Class | 0.1 μm | 0.2 μm | 0.3 μm | 0.5 μm | 1 μm | 5 μm | 10 μm | 25 μm |
| 1 | 10 | 2 | ||||||
| 2 | 100 | 24 | 10 | 4 | ||||
| 3 | 1000 | 237 | 102 | 35 | 8 | |||
| 4 | 10000 | 370 | 1020 | 352 | 83 | |||
| 5 | 100000 | 23700 | 10200 | 3520 | 832 | 29 | ||
| 6 | 1000000 | 237000 | 102000 | 35200 | 8320 | 293 | ||
| 7 | 352000 | 83200 | 2930 | |||||
| 8 | 3520000 | 832000 | 29300 | |||||
| 9 | 83200000 | 293000 |
US FED 209E (superceded) – counts mer m3 per size and greater
| S.I. | English | 0.1 μm | 0.2 μm | 0.3 μm | 0.5 μm | 1 μm | 5 μm | 10 μm | 25 μm |
| M1 | 350 | 75.5 | 30.9 | 10 | |||||
| M1.5 | 1 | 2140 | 265 | 106 | 35.3 | ||||
| M2 | 3500 | 757 | 309 | 100 | |||||
| M2.5 | 10 | 12400 | 2650 | 1060 | 353 | ||||
| M3 | 35000 | 7570 | 3090 | 1000 | |||||
| M3.5 | 100 | 26500 | 10600 | 3530 | |||||
| M4 | 75700 | 30900 | 10000 | ||||||
| M4.5 | 1000 | 35300 | 247 | ||||||
| M5 | 100000 | 618 | |||||||
| M5.5 | 10000 | 353000 | 2470 | ||||||
| M6 | 1000000 | 6180 | |||||||
| M6.5 | 100000 | 3530000 | 24700 | ||||||
| M7 | 10000000 | 61800 |
BS 1989 (superceded) – counts mer m3 per size and greater
| Class | 0.1 μm | 0.2 μm | 0.3 μm | 0.5 μm | 1 μm | 5 μm | 10 μm | 25 μm |
| C | 100 | 35 | 0 | |||||
| D | 1000 | 350 | 0 | |||||
| E | 10000 | 3500 | 0 | |||||
| F | 3500 | 0 | ||||||
| G | 100000 | 35000 | 200 | 0 | ||||
| H | 35000 | 200 | 0 | |||||
| J | 350000 | 2000 | 450 | 0 | ||||
| K | 3500000 | 20000 | 4500 | 500 | ||||
| L | 200000 | 45000 | 5000 | |||||
| M | 450000 | 50000 |
European Union GMP Guideline – counts mer m3 per size and greater
| Class | At Rest 0.5 μm | At Rest 5 μm | In Operation 0.5 μm | In Operation 5 μm |
| A | 3500 | 0 | 3500 | 0 |
| B | 3500 | 0 | 350000 | 2000 |
| C | 350000 | 2000 | 35000000 | 20000 |
| D | 3500000 | 20000 | N/A | N/A |