What is the Autoclave?
Autoclaves are also known as steam sterilizers, and are typically used for healthcare or industrial applications. An autoclave is a machine that uses steam under pressure to kill harmful bacteria, viruses, fungi, and spores on items that are placed inside a pressure chamber.
Who Invented the Autoclave Machine?
The first steam sterilizer built in 1880 by Charles Chamberland. The steam digester, a prototype of the autoclave that is better known now as a pressure cooker.
The science of disinfection and sterilization began in 1881 with the research of Robert Koch on the disinfecting properties of steam and hot air. He demonstrated the greater power of penetration exhibited by moist heat (steam) compared to dry heat. Finally, in 1933 modern autoclave technology was introduced with the first pressure steam sterilizer that controlled performance by measuring the temperature in the chamber drain line (thermostatic trap).
How Does an Autoclave Work?
Autoclaves are commonly used in healthcare settings to sterilize medical devices. The items to be sterilized are placed inside a pressure vessel, commonly referred to as the chamber. Three factors are critical to ensuring successful steam sterilization in an autoclave: time, temperature and steam quality.
To meet these requirements there are three phases to the autoclave process:
1. Conditioning Phase (C)
Air inhibits sterilization and must be removed from the chamber during the first phase of the sterilization cycle known as conditioning. In dynamic air removal-type steam sterilizers, the air can be removed from the chamber using a vacuum system.
2.Exposure Phase (S)
After the air is removed, the sterilizer drain closes and steam is continuously admitted into the chamber, rapidly increasing the pressure and temperature inside to a predetermined level. The cycle enters the exposure phase and items are held at the sterilization temperature for a fixed amount of time required to sterilize them.
3.Exhaust Phase (E)
During the final phase of the cycle, exhaust, the sterilizer drain is opened and steam is removed, depressurizing the vessel and allowing the items in the load to dry.
What is the Autoclave Temperature Range?
Commonly recommended temperatures for steam sterilization are 250° F (121° C), 270°F (132°C) or 275°F (135° C). To kill any microorganisms present, the items being sterilized must be exposed to these temperatures for the minimum time recommended by the manufacturer of the device being processed.
