There are a number of different types of sterilization, and all require that the temperature, gases, humidity, and pressure levels used are accurately monitored to ensure validity and effectiveness. These types of sterilization include: Steam â Steam sterilization, which was invented in 1880, is primarily used for glassware, surgical instruments, and medical waste. EtO/EO â This method uses Ethylene Oxide gas to sterilize items that cannot withstand the high temperatures or humidity created using other methods.