 Mist is generated from ultrasonic cavitation of water at room temperature and varying levels of relative humidity. This mist contains hydrogen peroxide which can be used as a measure of the amount of moisture present. As the level of relative humidity increases, so does the amount of hydrogen peroxide in the mist. This suggests that higher levels of moisture may increase the risk of respiratory virus transmission. This article was authored by Maria T. Julei, Carlos Alberto Hueto Aguilar, Christian F. Chamberlain and others.