By admin 
Cleanrooms are classified based on their air cleanliness, temperature, humidity and pressure control. The primary classification systems are:
International Organization for Standardization (ISO)
1. ISO 14644-1: Cleanrooms and associated controlled environments – Part 1: Classification of air cleanliness.
2. ISO Classes: 1, 2, 3, 4, 5, 6, 7, 8 and 9, with ISO 1 being the cleanest.
US Federal Standard 209E (Withdrawn, but still referenced)
1. Class 1: 1 particle/m³ (0.5 μm or larger)
2. Class 10: 10 particles/m³ (0.5 μm or larger)
3. Class 100: 100 particles/m³ (0.5 μm or larger)
4. Class 1,000: 1,000 particles/m³ (0.5 μm or larger)
5. Class 10,000: 10,000 particles/m³ (0.5 μm or larger)
6. Class 100,000: 100,000 particles/m³ (0.5 μm or larger)
EU GMP (Good Manufacturing Practice) Annex 1
1. Grade A: Sterile products, ISO 5 equivalent
2. Grade B: Clean areas, ISO 5-7 equivalent
3. Grade C: Clean areas, ISO 7-8 equivalent
4. Grade D: Clean areas, ISO 8-9 equivalent
Additional Classification Factors
1. Temperature: Typically 20-25°C (68-77°F)
2. Humidity: Usually 30-60% relative humidity
3. Pressure: Positive pressure (10-15 Pa) to prevent contamination
4. Air Change Rates: 10-600 air changes per hour
5. Filter Efficiency: HEPA (99.97% efficient at 0.3 μm) or ULPA (99.999% efficient at 0.12 μm)
Classification Process
1. Design and Construction: Cleanroom design and build
2. Testing and Validation: Initial testing and certification
3. Monitoring and Maintenance: Continuous environmental monitoring
4. Re-certification: Regular re-testing and re-certification
Cleanroom classification ensures controlled environments for sensitive industries, maintaining product quality, safety and regulatory compliance.