Isis fans from Big Ass Fan Co. help kill airborne pathogens in Rwanda’s Butaro Health Clinic by passing air over UV lights. The six-ward clinic runs the seven low-energy fans on generator power, which improves ventilation rates by about 20%—more than a quarter above World Health Organization guidelines. Impending access to an electrical grid will soon have the fans running 24/7. The clinic was designed by MASS Design Group, Boston, to use natural ventilation to reduce the spread of tuberculosis; the facility has outdoor walkways, alfresco waiting rooms, large windows, and the fans to help combat disease. The clinic, in partnership with the Government of Rwanda, Ministry in Health, Partners in Health, and the Clinton Foundation, opened earlier this year.