Abstract: A germicidal mask system to be worn by a user kills germs, viruses, or other pathogens which are located in the air to be breathed by the user. Before entering the mask, the air is exposed to ultra-violet radiation killing the undesirable germs, viruses, and other pathogens for which the ultra-violet radiation is lethal. In this manner only germ free air is provided to a user. Such a mask system would be useful to those users who are easily susceptible to contagious diseases. The germicidal mask system could also expose exhaled air from the user to kill any germs, viruses, or other pathogens exhaled by the user. Such a system would be useful to those who are continuously exposed to contagious diseases, such as doctors, or other health professionals, so as not to pass any diseases on to patients. This system also finds use in biological laboratories in order to prevent media cultures from being contaminated.