Sterilization is a cornerstone of the pharmaceutical manufacturing process. Several sterilization methods are employed in the industry based on the process requirement. The sterilization process is broadly classified into Cold and Hot Sterilization. Standard cold sterilization methods used in the process are chemical sterilization, ionizing radiation, and UV radiation, whereas the hot method is further classified into Moist heat sterilization and Dry sterilization. The moist heat methods use different media such as steam, super-heated water or steam-air mixture. In contrast, the Dry heat method uses hot air for sterilization.

The dry heat method is employed for sterilization and de-pyrogenation of the material used in pharmaceutical processing. This method is preferred for materials that may be damaged by moist heat or that are impenetrable to moist heat. Fundamentally, the Dry Heat Sterilization method destroys the microorganisms using hot air at temperatures ranging from 160°C to 180°C for exposure time up to 2 hrs. Similarly, de-pyrogenation is carried out for complete destruction and removal of pyrogens using hot air at higher temperatures up to 300°C and exposure time up to 2 hrs, depending on the requirement. Dry Heat Sterilization and de-pyrogenation are generally used for materials such as Glass Bottles, Vials, Ampoules, Containers (Stainless Steel & Aluminum), powders like sulphonamides and talcum powder.