A system including a head-mounted device having a face shield; a respirator coupled to or embodied in the head mounted device; a light having a light intensity; a light detector, and a computing device communicatively coupled to the at least one light detector that receive from the light detector data indicting a type and intensity of light, and determine that the light matches a particular type of light and whether it exceeds a threshold, and on the basis of this determination, modifies the intensity of the light.