Describe the autoclave cycles used in moist heat sterilization with typical parameters.

• A. Dry heat sterilization at 180°C.
• B. Ethylene oxide sterilization only.
• C. Steam sterilization uses saturated steam to transfer heat; typical parameters include 121°C for 15–20 minutes or 134°C for 3–5 minutes, depending on load and device.
• D. Radiation sterilization with gamma rays.

Answer: (C)

Moist heat autoclave cycles rely on saturated steam under pressure to transfer heat quickly and kill microbes. The steam penetrates items, displacing air and delivering heat to coagulate proteins and inactivate enzymes, making autoclaving an efficient method for sterilizing many instruments and wrapped packages. The typical approaches use either a 121°C (about 250°F) exposure for 15–20 minutes or a higher temperature of 134°C (about 273°F) for 3–5 minutes, with the exact choice depending on the load type, device, and whether air removal (prevacuum) is used to improve steam penetration. After the exposure, a drying phase is often included to remove residual moisture.

This is the standard description for autoclave cycles in moist heat sterilization. The other methods listed—dry heat at 180°C, ethylene oxide sterilization, and gamma-ray radiation—are different sterilization technologies with their own distinct parameters, not typical moist heat autoclave cycles.