Autoklave

An autoklave, or autoclave, is a pressure chamber used to sterilize equipment and materials by exposing them to saturated steam at elevated temperatures. The sterilization effect comes from steam under pressure, which raises the boiling point of water and allows higher temperatures than those attainable at ambient pressure. Typical cycles use either about 121°C at 15 psi (gauge) for 15–20 minutes, or about 134°C at 28–34 psi (gauge) for shorter times, depending on the load and desired sterility.

Most autoclaves operate through cycles that begin with heating and pressurization, followed by a sterilization exposure and a drying phase. Loads should be arranged to permit steam circulation; wrapped or porous items require longer or different exposure times. Types include gravity-displacement autoclaves, which expel air by gravity, and vacuum or prevacuum autoclaves, which remove air more effectively to improve steam contact. Autoclaves come in various sizes, from benchtop units to large industrial chambers, and feature different door designs and loading configurations.

Applications span healthcare, laboratories, and industry. They are used to sterilize surgical instruments, syringes, textiles, and lab consumables; to sterilize culture media, glassware, and certain plastics; and to process sterilization in some food and pharmaceutical operations. In manufacturing, autoclaves are also employed for curing certain composites and for retort-style sterilization of products.

Safety and validation are essential. Autoclaves operate at high temperatures and pressures, requiring proper training, protective equipment, and safety procedures. Sterilization verification uses chemical indicators and biological indicators (spore tests), with routine documentation. Regular maintenance of seals, gaskets, and safety valves is important to ensure reliable operation and sterility outcomes.

The concept and technology developed in the 19th century and have since become a standard tool in medicine, microbiology, and industrial processing.