Ventilation Assessment Tool
Improve Ventilation in Health Care to Reduce Infection Risks
The Ventilation Assessment Tool provides clinicians with information to start or enhance conversations with their facilities managers as they work together to improve air quality and reduce the spread of infection in the health care setting.
The Ventilation Assessment Tool is based on information from the Centers for Disease Control and Prevention (CDC) Guidelines for Environmental Infection Control in Health Care Facilities (2003) Table B.2, Ventilation Requirements for Areas Affecting Patient Care in Hospitals and Outpatient Facilities, which is derived from the Guidelines for Design and Construction of Hospitals and Health Care Facilities, 2001 edition.
While the information provided is based on the CDC Table B.2, users must consider locally and nationally adopted codes and standards to ensure compliance with the requirements. On July 5, 2016, the Centers for Medicare & Medicaid Services (CMS) adopted the 2012 edition of NFPA 99, Health Care Facilities Code, which references the 2008 edition of ANSI/ASHRAE/ASHE Standard 170, Ventilation of Health Care Facilities. Standard 170, which provides guidance on ventilation requirements for the health care field, is continually updated based on the latest available research and technological advancements, and users should consider information within the latest edition of Standard 170. If you have more questions about Standard 170, please reach out to your facility manager.
Using the tool, clinicians can select the type of work area (e.g., urgent care) and the room’s function (e.g., trauma room) and receive the appropriate ventilation requirements. The tool then provides recommendations based on CDC Environmental Infection Control Guidelines and the 2001 AIA Guidelines for Design and Construction of Hospital and Health Care Facilities. (See CDC Table B.2., Ventilation Requirements for Areas Affecting Patient Care in Hospitals and Outpatient Facilities.)
The following definitions apply to ventilation strategies and are specific to the tool and its proper application to health care spaces. Use these definitions to gain additional context for the results of the assessment.
Brief Definitions for Area
Emergency Care Area: A space where emergent medical services are conducted.
Invasive Patient Care Area: A space dedicated to invasive procedures (i.e., procedures that involve entering the body).
Other Clinical Service Areas: Areas that provide clinical services but that patients generally do not enter, such as laboratory spaces, pathology and central pharmacy.
Other Support Service Areas: Areas that provide other healthcare support but are usually located away from patient care spaces, such as central medical/surgical supply rooms, sterile processing rooms, and central laundry rooms.
Patient Care Area: A space in which clinicians and other staff provide care (e.g., evaluations, treatments) to patients.
Patient Care Support Area: Areas usually located adjacent to patient care spaces for support activities, such as medication rooms, soiled linen and trash chute rooms, and dietary day storage.
Specialty Care/Respiratory Area: A space housing patients who require frequent monitoring and intervention or patients whose clinical issues require special air handling,(includes ICU, AIIR rooms, protective environment rooms, burn treatment etc.).
Definitions for Results
- Air Change per Hour (ACH): Indicates how many times during one hour that the air volume from a space or room is replaced with “new” filtered or re-filtered air.
- Outdoor Air Change per Hour: The number of air changes per hour that must be made up of outside air. Because air is continually replaced, in reality this is a ratio of outside air to indoor air. Replacement air from outside is necessary to decrease odors and maintain a certain amount of filtered, clean air in the space.
- Outside Air (OA): External ambient air that enters a building through a mechanical ventilation system, through intentional openings for natural ventilation, or by infiltration. In health care settings, outside air should generally not be increased by opening doors or windows since air from adjacent spaces could be contaminated and is not controlled.
- Room Pressurization: The amount of pressure within a space or room compared to adjacent spaces or rooms.
- Negative Pressure: Air pressure is lower than pressure in adjacent spaces or rooms, which causes the air to flow into the negative pressure room from adjacent spaces or rooms. This airflow keeps infectious particles in the air inside the room, preventing spread of infection out of the room.
- Positive Pressure: Air pressure is higher than the pressure in adjacent spaces or rooms, which causes the air to flow from the positive pressure room out to adjacent spaces or rooms. This prevents infectious particles in the air from getting into the room.
- Air Exhausted Directly to Outdoors/Exhaust Air: Air that must be removed from a space due to contaminants, regardless of pressurization. Air from areas with contamination and/or odor problems is exhausted to the outside and not recirculated to the other areas.
- Air Recirculated by Means of Room Units/Recirculated Air – Air removed from a space and reused as supply air.
Definitions for additional context, not included in the results
Airborne Infection Isolation Room (AII Room or AIIR): A room that is used to isolate patients with infectious diseases that spread through air over longer distances and longer periods of time. AIIRs should provide negative pressure in the room; an airflow rate of 6-12 ACH; and direct exhaust of air from the room to the outside of the building or recirculation of air through a HEPA filter before returning to circulation.
Protective Environment Room (PE Room): A patient room that is intended to protect patients with severely compromised immune systems (e.g., those who have received allogeneic hemopoietic stem-cell transplant) from human and environmental pathogens.
Start the Conversation
The clinical liaison can refer to this script when discussing ventilation with their clinical, facilities and/or other colleagues. For example:
“I have identified my space as a _____________ space/room. The recommended number of air changes per hour (ACH) for this space is ____, with ____ minimum outside air changes per hour. This room is recommended to be at _______ pressure relative to the adjacent rooms and spaces so that air flows ______ the room. I would like to discuss any state or local requirements with you and your team, as well as any Centers for Medicare & Medicaid Services requirements and updated ASHE/ASHRAE guidance, as they may differ from these recommendations.”
The Project Firstline program is a national training collaborative led by the Centers for Disease Control and Prevention (CDC) in partnership with the American Hospital Association and the Health Research & Educational Trust (HRET), an AHA 501(c)(3) nonprofit subsidiary.
Want to learn more about Project Firstline? Contact ProjectFirstline@aha.org.
Project Firstline is a national collaborative led by the U.S. Centers for Disease Control and Prevention (CDC) to provide infection control training and education to frontline healthcare workers and public health personnel. AHA is proud to partner with Project Firstline, as supported through Cooperative Agreement CDC-RFA-OT18-1802. CDC is an agency within the Department of Health and Human Services (HHS). The contents of this webpage do not necessarily represent the policies of CDC or HHS, and should not be considered an endorsement by the Federal Government.
This content was funded in part by a cooperative agreement with the Centers for Disease Control and Prevention (grant number CK20-2003). The Centers for Disease Control and Prevention is an agency within the Department of Health and Human Services (HHS). The contents of this resource do not necessarily represent the policy of CDC or HHS, and should not be considered an endorsement by the Federal Government.