Install Differential Pressure Gauges in Airlocks to Maintain GMP Zoning

Equip Airlocks with Differential Pressure Gauges for Contamination Control

Remember: Differential pressure gauges in airlocks help prevent contamination by maintaining proper airflow direction between cleanroom zones.

Why This Matters in GMP

In GMP manufacturing, airlocks serve as buffers between areas of different cleanliness classifications. To maintain unidirectional airflow and minimize contamination risk, a positive pressure gradient must be consistently maintained from cleaner to less clean areas. Differential pressure gauges provide real-time monitoring and control of this gradient. Without such gauges, operators cannot confirm whether proper pressure conditions are being maintained, increasing the risk of cross-contamination. Installing and monitoring these instruments ensures that environmental integrity is preserved, particularly in sterile and high-risk areas where any pressure imbalance can compromise product quality.

Also Read: How to Achieve GMP Compliance for Clinical Trial Supplies and Investigational Products

Regulatory and Compliance Implications

FDA 21 CFR Part 211.42 emphasizes the importance of maintaining environmental control to prevent contamination. EU GMP Annex 1 mandates pressure differential monitoring and alarm systems for cleanrooms and airlocks. WHO GMP and Schedule M require continuous pressure differential records to be maintained between classified areas. Regulatory auditors routinely verify the presence, calibration status, and recorded data from these gauges. Lack of such controls is frequently cited as a major deficiency in facility inspections, especially in sterile manufacturing operations.

Implementation Best Practices

Install differential pressure gauges at all airlock entry and exit points between classified areas.
Calibrate gauges periodically and link them to centralized monitoring systems with alarms.
Set and document acceptable pressure ranges (e.g., ≥15 Pa between rooms) based on facility qualification data.
Train personnel to check and log differential pressure readings before room entry.
Investigate and document any deviations outside of set limits through CAPA systems.

Also Read: Use Material Transfer Notes (MTNs) When Moving Raw Materials

Regulatory References

FDA 21 CFR Part 211.42 – Design and Construction Features
EU GMP Annex 1 – Cleanroom Environmental Control
WHO GMP – HVAC System Monitoring
Schedule M – Differential Pressure Monitoring