Höyrysterilointi

Höyrysterilointi, commonly referred to as steam sterilization, is a method used to sterilize heat-stable medical devices, instruments and certain laboratory materials by exposing them to saturated steam under pressure. The process relies on high temperature and moisture to denature proteins in microorganisms, providing rapid and broad-spectrum microbial inactivation, including many spores.

A typical sterilization cycle involves preparing and loading items (often in appropriate packaging), placing them in a sterilizer chamber, and running cycles that include conditioning, sterilization at a set temperature and pressure, and a drying phase. Common operating conditions are around 121°C with a holding time of 15–20 minutes for wrapped items, or 134°C for shorter times, depending on the device, load configuration, and whether items are wrapped or unwrapped. Process validation and monitoring use mechanical indicators, chemical indicators and biological indicators to verify efficacy.

Applications cover healthcare facilities such as hospitals, clinics and dental offices, as well as diagnostic laboratories and pharmaceutical manufacturing. Höyrysterilointi is suitable for most heat-stable metal, glass and certain polymer instruments and for items that can be effectively sealed against moisture. It is generally not suitable for liquids, fragile or moisture-sensitive materials, and some plastics that may warp or degrade.

Standards and quality control are integral to practice, with guidelines and regulations provided by international and national bodies. Standards address sterilizer performance, cycle validation, routine monitoring, and recordkeeping. Common elements include biological testing of spore indicators, chemical indicators, and periodic equipment calibration to ensure a consistent sterility assurance level.