Diagram 1: The Key Parts of a Classic Autoclave.

This diagram highlights the key components of an autoclave, illustrating the essential components for the sterilization process.
This example features an Astell AMA440 Compact Top-Loading Autoclave. Front-loading benchtop versions are also available.

Diagram of the key parts of an autoclave used in the sterilization process
Key:
  1. Control Computer
  2. Chamber
  3. Heater
  4. Chamber Door
  5. Exhaust

Diagram 2: Loading the autoclave.

The chamber door is opened, and baskets filled with items requiring sterilization are loaded into the chamber.

Diagram of the process for loading an autoclave with sterilization items.
Key:
  1. Basket is lowered into the chamber
  2. Chamber door is unlocked and opened
  3. Water is refilled

Diagram 3: Heating and air removal.

The autoclave switches on its heater, which heats the water and generates steam. The exhaust valve is opened, allowing the steam to force air out of the chamber and through the exhaust outlet.

Diagram showing the autoclave heating water, generating steam, and removing air from the chamber.
Key:
  1. Chamber Door is closed and locked
  2. Heater is switched on
  3. Air is forced out of the Chamber

Diagram 4: Pressurization and sterilization.

Once all the air has been expelled from the chamber, the exhaust valve is shut. At this point, the steam being generated has nowhere to escape, causing the pressure inside the chamber to rise.
As the pressure increases, the steam exerts force on the water, requiring the water molecules to absorb more heat energy to convert into steam. As the water continues to be heated, steam is produced at temperatures exceeding 100°C.
When the temperature surpasses 121°C, the items in the chamber begin to undergo sterilization. At this temperature, sterilization requires a minimum of 15 minutes. At higher temperatures, the sterilization process is faster.

Diagram showing the pressurization and sterilization process inside an autoclave, highlighting pressure and temperature changes.
Key:
  1. Valve is shut

Diagram 5: Cooling.

As the chamber cools, the pressure inside drops to match the external environment. Once cooling is complete, the chamber door can be safely opened, and the sterilized items can be removed.

Diagram showing the cooling process in an autoclave, where pressure and temperature gradually decrease to safe levels.
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