Back Pressure Function

The back pressure function refers to the establishment of a certain pressure inside the sterilizer after the sterilization process to prevent sudden pressure changes when the sterilizer door is opened. This function is mainly used in sterilizers with back pressure (also known as pre-vacuum sterilizers).

During the sterilization process, the sterilizer with back pressure first draws out the air in the sterilization chamber through the vacuum system, and then introduces steam or gas for sterilization. When the sterilization process is completed, in order to maintain the safety of the sterilized items and the safety of the operator, the sterilizer will introduce a certain amount of steam or gas through the back pressure system at the end of the sterilization to balance the internal and external pressure.

The purpose of this is to prevent drastic pressure changes when opening the sterilizer door. If there is no back pressure function, when the sterilizer door is opened, the internal high-pressure steam or gas may be released rapidly, resulting in gas or hot steam ejection, which may cause injury to the operator and may also cause contamination of the sterilized items.

Therefore, the back pressure function plays an important role in balancing the pressure, protecting the operator and preventing contamination in the sterilizer with back pressure.

What is the mark of the sterilizer with drying function?

Symbolic Representation: There may be specific symbols on the equipment’s exterior or control panel to indicate a sterilizer with drying functionality. These symbols can be graphical, textual, or a combination of both.

Textual Description: The operational panel or labels of the equipment may explicitly state “Drying,” “Drying Function,” “With Drying,” or similar wording to indicate the presence of drying functionality in the sterilizer.

Icons: Some sterilizer manufacturers may use specific icons to represent drying functionality. These icons can display symbols such as a drying symbol, a sun, or patterns indicating airflow, allowing users to quickly identify the presence of drying functionality.

Instruction Manual and Specifications: The equipment’s instruction manual, user guide, or product specifications will provide explicit descriptions and explanations of the equipment’s features, including a description and details of the drying functionality.

What is the sterilization time and temperature of the bacteria bag?

The sterilization time and temperature for bacterial bags can vary depending on the specific sterilization method and equipment being used. Here are some general guidelines for commonly used sterilization methods:

Steam sterilization (Autoclave):

  1. Sterilization Time: Typically, bacterial bags are sterilized for 15 to 30 minutes.

Sterilization Temperature: The temperature during steam sterilization is typically around 121 to 132 degrees Celsius (250 to 270 degrees Fahrenheit).

Ethylene Oxide (ETO) sterilization:

  1. Sterilization Time: ETO sterilization requires a longer sterilization time, usually ranging from 2 to 6 hours.

Sterilization Temperature: The temperature during ETO sterilization is typically maintained at around 37 to 63 degrees Celsius (99 to 145 degrees Fahrenheit).

Dry Heat sterilization:

  1. Sterilization Time: Dry heat sterilization may take longer compared to other methods, typically ranging from 1 to 3 hours.

Sterilization Temperature: The temperature during dry heat sterilization can vary depending on the equipment used, but it is usually maintained at around 160 to 180 degrees Celsius (320 to 356 degrees Fahrenheit).

Correct Actions for Process Aborts

  1. Shut off steam supply: Firstly, stop the supply of steam to the high-pressure sterilizer. This can be done by shutting off the steam source or the corresponding valves. Ensure that the steam supply is completely stopped to prevent further pressure accumulation.


  1. Wait for pressure release: After stopping the steam supply, wait for the pressure inside the high-pressure sterilizer to gradually release. This may take some time, depending on the characteristics of the equipment and the pressure release mechanism. Follow the recommendations in the equipment’s operation manual regarding the waiting time.


  1. Open the vent valve: Once the pressure inside the high-pressure sterilizer is fully released, you can open the vent valve. This helps expedite pressure release and ensures that the internal pressure drops to a safe level. Make sure to open the vent valve only when the internal pressure has been completely released to avoid sudden release of high-pressure gas, which can cause injury.


  1. Perform a safe shutdown: After completing the pressure release, follow the safe shutdown procedure as outlined in the equipment’s operation manual. This may involve shutting off the power, draining water, or other necessary steps. Always follow the guidance provided in the equipment’s operation manual regarding the shutdown sequence and steps.