Final answer:
The minimum standard for autoclave sterilization is 121 °C for at least 20 minutes at 15 to 20 psi pressure. This ensures killing of microorganisms, including resistant endospores. Autoclaves use moist-heat to achieve complete sterilization, which can be confirmed using indicators within the autoclave.
Step-by-step explanation:
Minimum Time and Temperature for Autoclave Sterilization
The minimum time and temperature standard for sterilization using an autoclave is generally 121 °C for at least 20 minutes at a pressure of 15 to 20 psi. This is sufficient to sterilize most instruments and materials by killing vegetative cells, viruses, and particularly endospores, which are more resistant and can survive boiling temperatures. It is important to note that these conditions must be met uniformly throughout the material being sterilized, which is why the containers are left loosely closed, and instruments are loosely wrapped. Autoclaves use moist-heat sterilization to raise temperatures above the boiling point of water, ensuring effective sterilization without damaging the items.
Autoclaves are designed to achieve complete sterilization, which is defined as the complete removal or inactivation of all microorganisms, including endospores and viruses. To ensure proper sterilization, it is often necessary to use indicators within the autoclave that confirm the attainment of the necessary temperature and exposure time.
Different volumes and types of material might require adjustments in exposure times to ensure sufficient heat transfer. An autoclave is considered the most effective method of sterilization, as originally designed by Charles Chamberland while working with Louis Pasteur.