In with the good air.

The almost continuous reconstruction of healthcare facilities challenges the safety of patients because of the continual occupancy of hospitals. Traditional safety measures during construction have focused on avoiding hazards such as fire, mineral dust, and chemical aerosols. Since the development of transplant technology and other immunosuppressive therapies, opportunistic pathogens have become more frequent nosocomial pathogens. Immunocompromised patients are often devastated by infections, which can result in death. The removal of existing buildings to make way for new healthcare facilities and the renovation of existing buildings can result in aerosolization of such pathogens. In this issue of Infection Control and Hospital Epidemiology, Srinivasan et al. describe the generation of a tremendous dust cloud caused by explosive demolition. Their article provides data verifying that safety measures worked during a massive potential exposure to airborne contaminants. Before this demolition project, Thio et al. had described an outbreak of aspergillosis due to deficiencies in building ventilation systems at the same institution. Correcting these deficiencies was paramount to ensuring air quality during this subsequent demolition. In 1983, Streifel et al. described an explosive demolition at the University of Minnesota in preparation for renewal of the old hospital. The 1983 protective measures involved ventilation manipulation and building protection for areas housing immunocompromised patients. Srinivasan et al. used ventilation management methods that required continuous operation of ventilation systems so as to ensure building pressure. Except for smoke management, the importance of building depressurization was relatively unknown in 1983. Building depressurization seems to be an undiscovered problem in healthcare facilities and is dependent on continuous air balance considerations for mechanical ventilation. For example, it is easier to add exhaust systems to a building than to increase the supply air. This fact has contributed to the tendency of buildings to become depressurized, making it easier for unfiltered air to enter.