It is possible to use a UVC sterilizer and dryer to sterilize a CPAP (Continuous Positive Airway Pressure) mask and tube, but it's important to check the manufacturer's recommendations and guidelines before doing so.

CPAP equipment is typically made of materials that are safe for exposure to UVC light, which is commonly used for sterilization. However, some components of CPAP equipment, such as foam cushioning or rubber parts, may be sensitive to the heat generated by UVC light and may be damaged or degraded over time.

Additionally, it's important to ensure that the UVC sterilizer and dryer are designed for use with CPAP equipment and that they do not pose any risks to the user. For example, some UVC sterilizers use ozone for sterilization, which can be hazardous if inhaled in high concentrations.

If in doubt, it's recommended to follow the manufacturer's instructions for cleaning and sterilizing CPAP equipment, or to contact the manufacturer for more information.