The vacuum drying exit procedure of a pulsating vacuum sterilizer is a critical step following the sterilization cycle, directly affecting the drying effectiveness of the items and operational safety. Execution of this procedure should strictly follow the equipment manual and relevant GMP requirements. The standardized operational points are outlined below.
I. Pre‑Operation Preparation
Equipment status check: Inspect the door gasket for integrity, cracks, or deformation; confirm that the vacuum pump oil level is within the normal range; verify that the compressed air pressure meets equipment requirements (typically not less than 0.5 MPa).
Loading specifications: Items to be dried should be placed in dedicated sterilization baskets, with sufficient gaps between them to avoid blocking the chamber's airflow paths and temperature probe locations, ensuring even hot‑air circulation.
Correct program selection: On the control panel, select a validated vacuum drying program (which may be an independent drying program or a continuation of the sterilization cycle). Do not arbitrarily use unvalidated alternative programs.
II. Key Control Parameters During the Vacuum Drying Phase
Vacuum level: During drying, the absolute pressure inside the chamber should typically reach 0.08–0.095 MPa to effectively lower the boiling point of water and accelerate evaporation.
Temperature setting: The chamber temperature should be maintained at 70–90 °C, balancing drying efficiency with material tolerance, avoiding aging of instruments or packaging materials due to excessive heat.
Drying time: Determined by load material, packaging type, and loading volume; generally set for 30–60 minutes. The exact duration should be verified through heat‑penetration validation.
III. Operational Steps for Exiting the Procedure
Confirm drying completion: After the program runs for the set time, the system will automatically indicate that drying is complete. The operator should verify the on‑screen information.
Break the vacuum (venting): Slowly introduce sterile compressed air into the chamber through a sterile‑grade air filter, allowing the pressure to return smoothly to atmospheric level. The pressurization rate should be controlled at ≤0.01 MPa/s to prevent airflow impact that could damage items or disturb particulates.
Open the door and retrieve items: After the chamber pressure gauge returns to zero, wear heat‑resistant protective gloves, slowly open the door, and remove the dried items, being cautious of residual heat.
Data recording and archiving: Print or export the temperature, pressure, time profiles, and event logs from this run; sign and file them for traceability and future reference.
IV. Safety Precautions
Never forcibly open the chamber door during equipment operation, to prevent injury from high‑temperature steam or negative pressure.
The continuous running time of the vacuum pump must not exceed the maximum allowed by the equipment (typically ≤60 minutes) to avoid motor overheating and damage.
When removing items, pay special attention to metal utensils and glassware, which may retain significant residual heat; use insulated tools and handle gently to avoid burns or breakage.
