Verification ModeTransitioning from a single static verification to a full process verification that combines dynamic and static methods, strengthening the evaluation of the impact of operational intervention on airflow, and promoting the deep integration of verification and actual production quality control through video tracking and closed-loop management of result application.

Sealing of background environmentDuring intervention operations such as material transfer and equipment maintenance, it is necessary to demonstrate the airtightness of the background environment through airflow pattern research to ensure that external air does not enter critical areas through openings or gaps. Several pre operations require temporary opening of barrier devices (such as isolator doors), and such scenarios should be simulated in the study of airflow patterns to verify the impact of door opening operations on airflow stability and provide risk control measures (such as local laminar flow protection).

Unidirectional flow systemVisual airflow pattern research must be conducted to verify the uniformity and stability of unidirectional flow (such as vertical or horizontal laminar flow), ensure that the airflow is free of vortices and turbulence, and cover potential interference from equipment layout and personnel operations on the airflow.

Non unidirectional flow systemWhen there is a risk of pollution or complex operation areas (such as filling lines, material transfer areas), it is necessary to conduct airflow pattern research and confirm whether the airflow direction meets the design requirements through visual means (such as smoke and fog tests).

Confirmation of clean area and supporting air purification equipment：

• Airflow flow pattern testVerify whether the airflow direction and velocity comply with the design specifications through visual means such as smoke and fog tests and wind speed distribution maps.

• Pressure gradient verificationEnsure that the airflow direction is consistent with the pressure gradient to prevent cross contamination.

• dynamic simulationThe test should cover both static and dynamic operating conditions (such as equipment operation and personnel movement) to evaluate the airflow stability under actual production conditions.

Monitoring requirements for A-level zoneDuring critical operations such as filling and freeze-drying machine loading and unloading, continuous monitoring of suspended particles is required in Class A clean areas. The location and number of monitoring points should be determined based on the visualization of airflow patterns, with priority given to high-risk areas such as operation interfaces and equipment openings.

The production operating environment for the final sterilized productIn the production operation of the final sterilized product, it is necessary to evaluate the sterile operating environment based on the characteristics of the airflow pattern (such as A-level laminar flow under B-level background), to ensure that the airflow can effectively isolate the pollution risk caused by personnel activities.

Sterilization and sealing of freeze-drying machineThe steam sterilization program of the freeze dryer needs to be combined with the study of airflow patterns to verify the uniformity of the distribution of sterilization media (such as steam) in the chamber, ensuring that the discharge of condensed water does not affect the airflow path.

Aseptic process simulation test：

• Intervention design and dynamic assessment of airflowSimulation experiments need to cover dynamic disturbances in actual production (such as personnel activities and equipment operation), and evaluate the potential impact of intervention operations (such as personnel movement and equipment start stop) on the airflow direction in the clean area through visualization of airflow patterns.

• Environmental monitoring requirementsEnvironmental monitoring should be carried out throughout the entire simulation test process, and the representativeness of monitoring points should be confirmed by combining airflow pattern data (such as whether the airflow path in high-risk areas covers the monitoring points).

• Requirements for sterile raw material simulationThe simulation experiment batch needs to cover the surface of the equipment in contact with sterile products, and verify whether the airflow dead corners inside the equipment (such as pipelines and valves) are fully simulated through airflow visualization.

• Check environmental controlThe sample inspection environment should avoid external airflow interference and ensure that the inspection area maintains a unidirectional or laminar flow state through airflow pattern verification.

Change Impact AssessmentIf changes in factory facilities or equipment may affect the pressure gradient or airflow direction in the clean area (such as air supply system modification), the stability of the sterile environment needs to be re validated through airflow pattern research. If environmental changes (such as adjustments to the layout of the clean area) may disrupt the original airflow pattern, it is necessary to reconfirm the reliability of the aseptic process through visual research.

Oven and Tunnel OvenIt is necessary to confirm the uniformity of airflow distribution inside the oven through visualization of airflow patterns, avoid turbulence or dead corners, and verify the supporting effect of airflow on temperature uniformity by combining thermal distribution and thermal penetration testing. The tunnel oven needs to verify the pressure difference and airflow conditions through visualization of airflow patterns, and use smoke test visualization methods to dynamically verify the airflow path.