Sterilisation Methods

Steritech treats a wide range of products in order to make them safer by destroying bacteria, insects, viruses, parasites and other pathogens.  We use three methods of sterilisation.

Gamma irradiation

Gamma irradiation is a physical means of sterilisation or decontamination where products are exposed to gamma rays.  The gamma rays, which are a form of electromagnetic radiation of very short-wave lengths, act as a source of ionising energy that destroys bacteria and pests.  The isotope Cobalt-60 is the most common source of gamma rays for irradiation processing and is used by Steritech.  The Cobalt-60 is manufactured specifically for the irradiation process and is housed in specially designed chambers operating to strict standards and regulations. 

Steritech’s gamma irradiation process does not involve sufficient energy to make treated products radioactive. The product being treated does not come into contact with the Cobalt-60 and when the process is complete the energy does not remain in the product. Gamma irradiation is known as a ‘Cold Process’ as the temperature of the processed product does not increase significantly. It is also a chemical free process that is not reliant on humidity, temperature or pressure and can be applied to packaged goods.

Ethylene oxide (EtO)

EtO is a gas that sterilises via its action as a powerful alkylating agent.  EtO prevents cell reproduction and as such can kill all known viruses, bacteria and fungi, including bacterial spores. EtO is compatible with a number of materials.  It is commonly used in the medical field for the sterilisation of medical equipment and Australian hospitals are among some of Steritech’s major customers for this process. 

The process of applying EtO is a carefully managed one involving multiple stages designed first to bring the product to the necessary temperature and moisture content, then the product is placed in a special chamber where all air is removed and controlled amounts of steam and EtO are introduced.  Finally, the product exits the chamber and is conveyed into the high velocity aeration room, where gas residuals are lowered to required levels of a period of at least 48 hours. 

Heat treatment

This process involves applying dry heat to the product to be treated in a specially designed climate control chamber.  The heat eliminates bacteria and other pathogens and the process is used in a range of industries, including cosmetics, pharmaceuticals, and food and agriculture.  The primary use of Steritech's dry heat treatment (based in Wetherill Park NSW) is for the treatment of imported goods as required by the Australian Quarantine and Inspection Service (AQIS).