Flaming: Scalpels and neck of flasks, bottles and tubes are exposed for a few seconds, but it is of uncertain efficacy.
Hot Air Sterilizer (Oven): it is essential that hot air should circulate between the objects being sterilized and these must be loosely packed and adequate air space to ensure optimum heat transfer. It is done by applying 160 0c for 1 hour. Use: Sterilizes glassware, oils, greases, lubricants and powders.
Moist heat: It is preferred to dry heat due to more rapid killing. Moist heat can be used by the following methods.
Boiling: It is not reliable method of sterilization. It is done by applying 100 0c for 30 minutes. Used for sterilizing catheters, dressing and fabrics.
Tyndallization : Intermittent steaming (Fractional sterilization) Steaming of the material is done at 100 0c for 30 minutes on three consecutive days. The principle is that spores which survived the heating process would germinate before the next thermal exposure and then would be killed. It is used for sterilizing heat sensitive culture
media containing materials carbohydrates, egg or serum.
Pasteurization: It is the process of application of heat at temperature of