Clean Room Classification
| ISO 14644-1 | Classe 3 | Classe 4 | Classe 5 | Classe 6 | Classe 7 | Classe 8 | 
| Federal Standard 209E | 1 | 10 | 100 | 1.000 | 10.000 | 100.000 | 
| EUCGMP | - | - | A/B | - | C | D | 
| Ricambi orari di aria | 360/540 | 300/540 | 240/480 | 150/240 | 60/90 | 5/48 | 
BS 5295 cleanroom standards
| maximum particles/m³ | ||||||
| Class | ≥0.5 µm | ≥1 µm | ≥5 µm | ≥10 µm | ≥25 µm | |
| 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 5 μ GMP EU classification
| Class | maximum particles/m³[11] | |||
| At Rest | At Rest | In Operation | In Operation | |
| 0.5 µm | 5 µm | 0.5 µm | 5 µm | |
| 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 | 

















