Caring for Our Children (CFOC)

Chapter 5: Facilities, Supplies, Equipment, and Environmental Health

5.2 Quality of the Outdoor and Indoor Environment

5.2.1 Ventilation, Heating, Cooling, and Hot Water Ensuring Access to Fresh Air Indoors

Content in the STANDARD was modified on 8/25/2016 and 09/23/2021.

COVID-19 Modification as of March 20, 2023.


After reading the CFOC standard, see COVID-19 modification below (Also consult applicable state licensure and public health requirements).

As much fresh outdoor air as possible should be provided in rooms occupied by children. Screened windows should be opened whenever weather and the outdoor air quality permits (1). When windows are not able to be opened, rooms should be ventilated, as specified in Standards The specified rates at which outdoor air must be supplied to each room within the facility range from fifteen to sixty cubic feet per minute per person (cfm/p). The rate depends on the activities that normally occur in that room. Indoor air should be kept as free from unnecessary chemicals and fragrances as possible.

Ionizers or products that use UV lights are not recommended. Do not use air cleaner devices with ozonators, ultraviolet (UV) lights, or ionization features, since they are unnecessary and some produce ozone, which can be harmful and trigger respiratory problems such as asthma.

COVID-19 modification as of March 20, 2023: 

Improving ventilation is an important COVID-19 prevention strategy that can reduce the number of virus particles in the air. In response to the Centers for Disease Control and Prevention’s guidance on ventilation, it is recommended that staff:

  • Allow fresh, outdoor air into the building to help keep virus particles from remaining indoors.
  • Increase the flow of air from outside, using caution in highly polluted areas. See CDC’s webpage for more information about local air quality.
  • Open all screened doors and windows, when safe to do so. Even slightly opened windows can help.
  • Do not open windows and doors if doing so is unsafe for children and staff (e.g. risk of falling, triggering asthma symptoms). Have window guards in place on all windows.
  • When opening windows or doors is unsafe, consider other approaches for reducing the amount of virus particles in the air, such as portable air filters and exhaust fans.
  • Use child safe portable fans or ceiling fans to increase the circulation of fresh air from open windows. Placing a fan by an open window to blow inside air out encourages airflow throughout the room.
  • Run heating, ventilation, air conditioning (HVAC) systems at maximum outside airflow for 2 hours before and after the center or home is in use for child care. If units do not have air conditioning, run the “fan” setting.
    • Ensure exhaust fans in areas such as restroom, kitchens, cooking areas are functional and running at full capacity.
  • Clean and change filters as recommended by manufacturer. If system allows, ensure filters are MERV 13 (Minimum Efficiency Reporting Value 13) or higher, as recommended by the American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE).
    • ASHRAE currently recommends using a minimum MERV 13 filter, which is at least 85% efficient at capturing particles including SARS-CoV-2 virus particles.
  • Consult with your building’s facility staff or administrators to ensure your ventilation systems operate properly and provide acceptable indoor air quality for the current occupancy level for each space. Work with a ventilation consultant as needed. 
  • If your program does not have an HVAC system, or programs want extra filtration, consider using a portable high-efficiency particulate air (HEPA) cleaner. HEPA cleaners trap particles exhaled when breathing, talking, singing, coughing, and sneezing.
    • Select HEPA cleaners of the right size for the room(s). For example, select a HEPA fan system with a Clean Air Delivery Rate (CADR) that meets or exceeds the square footage of the room. See EPA’s Guide to Air Cleaners in the Home for more information.
  • Spend more time outside, as weather permits.


When Transporting Children

  • Open windows on transport vehicles (cars, vans, etc.) when safe to do so and as weather permits.

Additional Resources:


American Society of Heating and Air-Conditioning Engineers (ASHRAE)

California Childcare Health Program

Centers for Disease Control and Prevention

Children’s Environmental Health Network

New Jersey Department of Health

Environmental Protection Agency (EPA)

Harvard School of Public Health and UC, Colorado Boulder


The health and well-being of both the staff and the children can be greatly affected by indoor air quality. The air people breathe inside a building can be contaminated with germs shared between people, chemicals emitted from common consumer products and furnishings, and polluted outdoor air entering into the program.1, 2 Additionally, the presence of dirt, moisture, and warmth encourages the growth of mold and other contaminants, which can trigger allergic reactions and asthma.3

Children’s exposure to contaminated or polluted air (indoor and outdoor) is associated numerous health effects such as respiratory problems including increased asthma incidence, allergies, preterm birth, low birth weight, neurodevelopmental disorders, some cancers, IQ loss, and risk for adult chronic diseases .2-5 Children are more vulnerable to air pollution because their organs (respiratory, central nervous system, etc.) are still developing and they breathe in more air relative to their weight than adults.5 Air circulation is essential to clear infectious disease agents, odors, and toxic substances in the air.

Carbon dioxide levels are an indicator of the quality of ventilation. Higher Oxygen levels and lower Carbon Dioxide from fresh air promotes a better learning environment.7 Air circulation can be adjusted by a properly installed and adjusted heating, ventilation, air conditioning, and cooling (HVAC) system as well as by using fans and open windows.

Qualified engineers can ensure heating, ventilation, air conditioning (HVAC) systems are functioning properly and that applicable standards are being met. The American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) Website includes the qualifications required of its members and the location of the local ASHRAE chapter. The contractor who services the HVAC system should provide evidence of successful completion of ASHRAE or comparable courses.



The following organizations can provide further information on air quality and on ventilation:

  • The American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE)
  • The U.S. Environmental Protection Agency (EPA) Public Information Center
  • The American Gas Association (AGA)
  • The Edison Electric Institute (EEI)
  • The American Lung Association (ALA)
  • The U.S. Consumer Product Safety Commission (CPSC)
  • The Safe Building Alliance (SBA)
Center, Early Head Start, Head Start, Large Family Child Care Home, Small Family Child Care Home
RELATED STANDARDS Playing Outdoors Protection from Air Pollution While Children Are Outside Indoor Temperature and Humidity Heating and Ventilation Equipment Inspection and Maintenance Ventilation When Using Art Materials Ventilation of Recently Carpeted or Paneled Areas Ventilation to Control Odors Carbon Monoxide Detectors
  1. American Lung Association. Ventilation: How Buildings Breathe. Updated April 8, 2020. Accessed July 28, 2021.
  2. United States Environmental Protection Agency. Volatile Organic Compounds' Impact on Indoor Air Quality. Accessed July 28, 2021.
  3. Gaspar, F. W., et al. Ultrafine, fine, and black carbon particle concentrations in California childā€care facilities. Indoor air. 2018;28.1: 102-111. Accessed July 28, 2021.
  4. Danh C. Vu, Thi L. Ho, Phuc H. Vo, et al. Assessment of indoor volatile organic compounds in Head Start child care facilities. Atmospheric Environment. 2019; 215 ( 116900):1352-2310,
  5. Brumberg, H. L., Karr, C.J.. Ambient Air Pollution: Health Hazards to Children. Pediatrics. 2021: 147.6.
  6. American Society of Heating, Refrigeration and Air Conditioning Engineers. Standard 62.1 -2019: Ventilation for Acceptable Indoor Air Quality. ISSN 1041-2336. Published October 2019. Accessed July 28, 2021.
  7. Marcotte D. Something in the air? Air quality and children's educational outcomes. Economics of education review. 2017;56. doi:10.1016/j.econedurev.2016.12.003

Content in the STANDARD was modified on 8/25/2016 and 09/23/2021.

COVID-19 Modification as of March 20, 2023.