UV light can be harmful just as the sun’s UV light can be when someone is exposed for too long a time. One should neither look at the touch of a UV light bulb while it is on for any length of time. Fortunately, when the UV light system is installed in your HVAC system, there is no direct or harmful exposure to you or your family. Remember to power off your purifier before replacing the lamps and do not look directly at a lamp that is powered on.