As health and school officials deal with a second wave of the H1N1 virus (swine flu), new information on health consequences of exposure to airborne infectious diseases and implications for the design, installation, and operation of HVACR systems is available from the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE).

“ASHRAE Position Document on Airborne Infectious Diseases” (www.ashrae.org/positiondocuments) addresses the impact of ventilation on disease transmission, diseases for which airborne transmission is important, and control strategies, including dilution ventilation, filtration, and ultraviolet germicidal irradiation.