About Sterilization

Sterilization and Disinfection

Definition of sterilization and disinfection (pasteurization).

Sterilization

Kill or eliminate all living microorganisms not only pathogens but also non-pathogens.

*Supplement

Killing characteristic of bacteria is expressed by an exponential function.
Therefore, the presence of growing microorganisms is expressed by probability, and even if this probability is reduced to a very low value but it does not become to zero.

Example)
  • High-Pressure Steam Sterilizer
  • Ethylene Oxide Gas Sterilizer
  • Dry-Heat Sterilizer, etc.

Disinfection

Eliminate to the risk of infection by killing or eliminating the pathogenic microorganisms.

Example)
  • Boil Disinfection
  • Various drugs disinfection etc.

Sterilization

It refers to depriving the vitality of bacteria, but it is used in a broad meaning to inactivate many types of microorganisms such as spores and molds.

Summary of a various sterilization methods and disinfection methods

High-Pressure Steam Sterilizer

This method is a widely used for sterilization of steel surgical instruments, linens and rubber that can endure high temperature and high humidity on hospital, laboratory and industrial fields.
The time and cost required for sterilization are relatively low, and the range of application is wide.
This method has the longest history and high reliable.

Dry-Heat Sterilization

This method is used for sterilization of glassware, ointments and powder, etc.. And its applicable range is limited because the operating temperature is very high (more than 160℃).

Ethylene Oxide Gas Sterilizer

It has excellent permeability to the sterilized product, so it can be widely used. But the sterilization cost and time are relatively large and there is needed the caution of handling against toxicity, gas removing and ventilation of the work environment, etc. enough.

Low-Temperature plasma Sterilizer

The one that has been put into practical use is hydrogen peroxide plasma sterilization that combines hydrogen peroxide vapor and high-frequency energy. But this method is necessary to caution because it has poor permeability against thin tubes or narrow gaps.

Flame Sterilization

It is used for instrument sterilization of inspection (especially bacterial inspection) tools and sterilization of waste from each department.

Boil disinfection

This method has been used widely for steel surgical medical instruments, syringes etc., but it is being replaced by high-pressure steam sterilizer.

Circulation steam disinfection

The internal pressure never exceeds more than atmospheric pressure because the steam which is generated or sent into the chamber exhausts to the outlet.
Therefore, the operating temperature is 100 degrees C.

Disinfectant

It is used single or in combination depending on various cases.

The source:Knowledge of high-pressure steam sterilizer – Basic
Publishing:Sakura Seiki Co., Ltd. Education Center