I. Moisture content is a critical parameter for pharmaceutical compressed air
In pharmaceutical manufacturing, compressed air comes into direct or indirect contact with products, packaging materials, or cleanroom environments, and its moisture content directly affects the risk of microbial growth, equipment corrosion, and formulation stability. Excessive moisture can lead to condensation in pipelines, filter element failure, and interruptions in aseptic processes; therefore, it must be strictly controlled.
II. Core regulatory references: ISO ISO 8573‑1 and GMP requirements
The internationally recognized standard for classifying compressed air quality ISO ISO 8573‑1 divides moisture content (i.e., pressure dew point) into several classes. In the pharmaceutical industry, a level of ≤ -40℃ pressure dew point (corresponding to ISO Class 2 under ISO 8573‑1:2010) is commonly required; for certain high-risk processes (such as lyophilization and aseptic filling), even stricter control down to -70℃ (Class 1) is mandated.
III. Additional GMP requirements for洁净compressed air
The “Good Manufacturing Practice for Pharmaceuticals” emphasizes that compressed air must undergo three-stage treatment—oil removal, moisture removal, and sterilization—and that dew point, oil content, and microbial levels should be continuously monitored. Moisture content must be tracked in real time using online dew point instruments, with the data incorporated into deviation management and trend analysis systems.
IV. Key points for validation and routine control
- At the system design stage, specify dew point control targets and the drying method (e.g., a combined refrigeration‑adsorption approach);
- After installation, complete validation of the compressed air system (IQ/OQ/PQ), including dew point distribution testing;
- Regularly calibrate dew point sensors and maintain historical records to support ongoing process verification.