To sterilize with steam certainly and quickly steam under pressure in the autoclave, the autoclave is essentially a metal chamber with a door that can be closed very tightly.
Boiling water can never be trusted for absolute sterilization because its maximum temperature is 100ºc. Boiling water can generally be used for contaminated dishes, bedding and bedpans.
-Sterilization by dry heat
Dry heat sterilization is carried in hot- air ovens or continuous infrared ovens using 160ºc for an hour or 190ºc for 19 min. (5) Sterilization by dry heat is an efficient method for the sterilization and disposal of contaminated materials at a high temperature, it has a particular application for pathological waste materials .(135)