Sterilization is the total destruction of all forms of life, including bacterial spores. It is best done with heat, either dry heat in an oven, or steam under pressure in an autoclave.
The basis of aseptic surgery is to kill all micro-organisms on all instruments and dressings, preferably by exposure to steam under pressure. If this is impractical, immersion in boiling water for 10 minutes will not kill spores, particularly those of tetanus and gas gangrene. A boiling water ''sterilizer' is therefore badly named.
Ultrasonic cleaning has long been recognized as one of the most effective methods of cleaning across a diverse range of applications. No other method is as efficient for cleaning hard substrates or intricate parts.
No other system is as effective as ultrasonic's at cleaning inaccessible and hard to reach areas of items. The microscopic bubbles caused by the ultrasonic's are easily able to penetrate screw threads, hinges and other hard to reach areas.
It is this ability to clean even the most inaccessible areas which makes ultrasonic's an ideal cleaning system for medical instruments. The intricate design of these items means that blood and other items contaminate hard to clean areas. Ultrasonic cleaning is able to remove these items with an effective yet delicate cleaning action.
Pasteur showed that once a medium is sterilized, it will remain sterile until contaminated by microorganisms (i.e., they do not appear by spontaneous generation.).
Heating is one of the most convenient methods for sterilization. Simple boiling at 100°C, however, is not completely effective for sterilization because many spores can survive this temperature. However, the boiling point of water goes up when exposed to increased pressures. In a pressure cooker where the pressure is 15 pounds/sq inch (1 atmosphere) above standard pressure (760 mm Hg), water boils at 121°C. This temperature kills
Ultraviolet germicidal irradiation (UVGI) is a disinfection method that uses short-wavelength ultraviolet (UV-C) light to kill or inactivate microorganisms.
