@windwalker @macjane The N95 mask with an exhalation valve in the front will protect the wearer, but it doesn't protect others. In fact, if the wearer is infected, the front valve will concentrate the infected air and shoot it toward any person in front of the wearer. To guard against unknowingly infecting others, a second, cloth or lobby-type disposable mask should be worn over the N95 one to cover the valve.