Heating, Ventilation, and Air Conditioning Systems in Health-Care Facilities

Heating, ventilation, and air conditioning (HVAC) systems in health-care facilities are designed to maintain the indoor air temperature and humidity at comfortable levels for staff, patients, and visitors.

control odors;

remove contaminated air;

facilitate air-handling requirements to protect susceptible staff and patients from airborne health-care associated pathogens; and

minimize the risk for transmission of airborne pathogens from infected patients.

An HVAC system includes an outside air inlet or intake; filters; humidity modification mechanisms (i.e., humidity control in summer, humidification in winter); heating and cooling equipment; fans; ductwork; air exhaust or out-takes; and registers, diffusers, or grilles for proper distribution of the air (Figure 1). Decreased performance of healthcare facility HVAC systems, filter inefficiencies, improper installation, and poor maintenance can contribute to the spread of health-care associated airborne infections.

The American Institute of Architects (AIA) has published guidelines for the design and construction of new health-care facilities and for renovation of existing facilities. These AIA guidelines address indoor air-quality standards (e.g., ventilation rates, temperature levels, humidity levels, pressure relationships, and minimum air changes per hour [ACH]) specific to each zone or area in health-care facilities (e.g., operating rooms, laboratories, diagnostic areas, patient-care areas, and support departments).

 These guidelines represent a consensus document among authorities having jurisdiction (AHJ), governmental regulatory agencies (i.e., Department of Health and Human Services [DHHS]; Department of Labor, Occupational Safety and Health Administration [OSHA]), health-care professionals, professional organizations (e.g., American Society of Heating, Refrigeration, and Air-Conditioning Engineers [ASHRAE], American Society for Healthcare Engineering [ASHE]), and accrediting organizations (i.e., Joint Commission on Accreditation of Healthcare Organizations [JCAHO]). More than 40 state agencies that license health-care facilities have either incorporated or adopted by reference these guidelines into their state standards. JCAHO, through its surveys, ensures that facilities are in compliance with the ventilation guidelines of this standard for new construction and renovation.

Wednesday, April 13, 2022


Centers for Disease Control and Prevention (CDC)

Please Check out file at the following link

Modes of Transmission of Airborne Diseases

Environmental Infection Control in Health-Care Facilities

Disinfection in the Hemodialysis Unit

Transmissible Spongiform Encephalopathies in humans and in animals

Air Disinfection