A sterilizer is a device for killing pathogens such as bacteria (sterilization), Steam sterilization by steam sterilizers or autoclaves, sterilize by heating under pressure and using steam. Such devices are mainly used in medicine to sterilize or disinfect surgical instruments and other instruments. The devices are also used in biotechnology for sterilizing liquid culture media or glassware. For steam sterilization with autoclaves, the standard procedure of the German Pharmacopoeia prescribes a temperature of at least 121 °C at 1 bar overpressure (= 2 bar abs.) for 20 minutes. Programs with 134 °C at 3 bar are also common, especially for glassware without liquids and instruments. Hot air sterilization using hot air sterilizers, i.e. sterilization with dry heat. Higher temperatures of over 180 °C to 250 °C are required, but a minimum sterilization time of 30 minutes. These devices are used to sterilize preparation utensils and sometimes also smaller glassware without plastic components.