The pharmaceutical cleanroom classification Grades A, B, C, and D are used to define different levels of cleanliness in pharmaceutical manufacturing facilities. Grade A is required for the highest-risk operations such as aseptic filling areas, rubber stopper holding zones, open ampoule areas, open vial areas, and zones where aseptic assembly or sterile connections are performed.
Cleanroom Classification Grades A–D in Pharmaceutical Manufacturing
High-risk pharmaceutical operations—such as filling areas, stopper container zones, open ampoule or vial handling, and aseptic assembly/connection areas—must be performed in controlled environments. These areas are typically maintained using laminar airflow workstations or laminar flow hoods.
The laminar airflow (unidirectional airflow) system must deliver uniform air distribution across the working zone at a velocity of 0.36–0.54 m/s (guideline value). The state of the laminar flow must be demonstrated with data and requires validation.
In enclosed isolators or glove boxes, unidirectional flow or appropriately reduced airflow velocities may be used according to system design.
Grade B
Grade B is the background cleanroom environment for Grade A high-risk operations such as aseptic preparation and filling.
Grades C and D
Grades C and D are used for less critical cleanroom operations during sterile drug production, such as solution preparation, equipment washing, or component staging.
Cleanroom Grades and Particle Limits
Allowed Number of Airborne Particles per m³
Below is the complete text-based table converted from the document:
Maximum Number of Particles Allowed per Cubic Meter (m³)
| Cleanroom Grade | Static Conditions ≥0.5 μm | Static Conditions ≥5 μm | Dynamic Conditions ≥0.5 μm | Dynamic Conditions ≥5 μm |
|---|---|---|---|---|
| Grade A | 3,520 | 20 | 3,520 | 20 |
| Grade B | 3,520 | 29 | 352,000 | 2,900 |
| Grade C | 352,000 | 2,900 | 3,520,000 | 29,000 |
| Grade D | 3,520,000 | 29,000 | Not specified | Not specified |
Additional Notes
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Grade A ≈ Class 100
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Grade B ≈ Class 10,000
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Grade C ≈ Class 100,000
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Grade D ≈ Class 300,000
Grade A requires the strictest environmental control, with Grade B serving as its background area.
Grades C and D correspond to less stringent clean zones used for non-aseptic stages.
| Cleanliness level of suspended particles in clean area air | |||||||
| Air cleanliness level | The maximum concentration limit (PC/M²) for particle sizes less than or equal to those in the table is required. | ||||||
| ISO standards | Chinese Standards | 0.1µm | 0.2µm | 0.3µm | 0.5µm | 1µm | 5µm |
| Level 1 | 10 | 2 | |||||
| Level 2 | Level 1 | 100 | 24 | 10 | 4 | ||
| Level 3 | Level 5 | 1000 | 237 | 102 | 35 | 8 | |
| Level 4 | Level 10 | 10000 | 2370 | 1020 | 352 | 83 | |
| Level 5 | Level 100 | 100000 | 23700 | 10200 | 3520 | 832 | 29 |
| Level 6 | Level 1000 | 1000000 | 237000 | 102000 | 35200 | 8320 | 293 |
| Level 7 | Level 10,000 | 352000 | 83200 | 2930 | |||
| Level 8 | Level 100,000 | 3520000 | 832000 | 24300 | |||
| Level 9 | Level 300,000 | 35200000 | 8320000 | 2930000 | |||