Control and management of hospital indoor air quality.
BACKGROUND
The complex hospital environment requires special attention to ensure healthful indoor air quality (IAQ) to protect patients and healthcare workers against hospital-acquired (nosocomial) infections and occupational diseases. The aim here is to recommend effective guidelines for the control and management of hospital IAQ.


METHODS
The authors have done an extensive literature review and conducted comprehensive IAQ assessments in nine hospitals. It is noted that the IAQ measurements are not presented in this paper because of confidentiality. However, the IAQ analysis was studied carefully in the development of the recommendations given in this paper.


RESULTS
The airborne chemical and microbiological contaminants of concern for hospitals have been identified and the major emission sources, monitoring methods, and exposure limits have been well documented and are reviewed here. Proper engineering system designs and operations are also reviewed, with recommendations for effective dilution and removal of the contaminants. The control and mitigation measures cover mechanical ventilation, filtration, differential pressure control, directional airflow control, local exhaust ventilation, and ultraviolet germicidal irradiation (UVGI) disinfection. Their applications in critical environments, such as operating theatres, isolation rooms, and other typical units, such as outpatient departments and laboratories, are also considered.


CONCLUSIONS
Effective IAQ monitoring methods and mitigation measures suitable for the hospital environment have been identified. Accordingly, strategies for the implementation of a hospital indoor air quality management system are recommended. Healthcare workers, hospital engineers, and administrative staff can use the above as guidelines to manage and run their hospitals with healthful indoor air quality.
Leung
Michael
M
Department of Mechanical Engineering, The University of Hong Kong, Kowloon, Hong Kong.
Chan
Alan H S
AH
D000391:Air Microbiology; D000392:Air Movements; D000397:Air Pollution; D016902:Air Pollution, Indoor / Q000517:prevention & control*; D004780:Environment, Controlled; D004784:Environmental Monitoring; D005160:Facility Design and Construction; D005374:Filtration; D017408:Guidelines as Topic; D006740:Hospital Administrators; D006761:Hospitals / Q000592:standards*; D006801:Humans; D017053:Infection Control / Q000379:methods; D012196:Review Literature as Topic; D014691:Ventilation