What is the recommended minimum temperature setting for an autoclave to effectively inactivate biohazards, including spores?

The recommended minimum temperature setting for an autoclave to effectively inactivate biohazards, including spores, is 121 ºC (250 ºF). This temperature is established based on its efficacy in achieving sterilization, particularly for resistant organisms such as bacterial spores. The autoclave combines this high temperature with increased pressure, which significantly enhances the penetration of steam and the effectiveness of the sterilization process.

At 121 ºC for a specific duration (typically at least 15-30 minutes), the conditions are sufficient to achieve the required lethality of microbes including the most resilient spores, making this the standard for sterilization procedures in laboratory and medical settings. This temperature and pressure combination effectively disrupts cellular structures and denatures proteins, ensuring that viable organisms are eliminated.

Higher temperatures, such as 145 ºC (293 ºF) and 160 ºC (320 ºF), while effective for sterilization, are not necessary for standard biohazard decontamination. They could potentially lead to material degradation or are not routinely used in standard autoclave sterilization protocols. Similarly, a temperature of 100 ºC (212 ºF) is insufficient for ensuring the sterility of biological materials, particularly those that are heat-resistant.