CDC Recommends Improving Building Ventilation to Reduce Spread of Respiratory Infections

Improving a building’s ventilation system can increase the delivery of clean air and help prevent the spread of respiratory infections, according to a CDC COVID-19 update.

Per the new guideline, “good ventilation is essential to maintaining a healthy indoor environment and protecting building occupants from respiratory infections.” According to the CDC, protective ventilation strategies are important to prevent the accumulation of droplets and small particles containing viruses that people breathe out.

This published guidance reviews basic strategies such as maintaining heating, ventilation, and air conditioning (HVAC) systems. Additionally, the CDC recommends regular filter changes and making sure that filters fit properly.

The CDC also suggests enhanced strategies for improving ventilation, filtration, and air treatment systems in building to lower the concentration of viral particles in the air. These strategies include:

• Delivering 5 or more air changes per hour (ACH) of clean air, which may include a combination of air supply, filtration, and air treatment strategies
• Upgrading to minimum efficiency reporting values-13 (MERV-13) filters or higher, when possible.
• Setting the HVAC system to the “ON” mode opposed to the “AUTO” mode
• Adding fresh air to indoor spaces by opening windows, doors, and using exhaust fans
• Using air purifiers to remove germs from the air
• Installing ultraviolet (UV) air treatment to kill germs in the air
• Using portable carbon dioxide (CO₂) monitors to reduce readings above 800 parts per million (ppm)

Furthermore, low-cost and low-energy strategies are available, and the CDC encourages buildings to participate in the Clean Air in Buildings Challenge, which provides guidance for ways that building owners and operators can use to improve indoor air quality and reduce the spread of viral respiratory infections.

“Ventilation systems bring fresh, outdoor air into rooms, filter or disinfect the air there, and improve air flow,” according to the guidance. “Making ventilation system upgrades or improvements in your building can increase the delivery of clean air and reduce potential contaminants in indoor spaces. This can help reduce the number of viral particles in the air.”

Reference

Improving ventilation in buildings. Centers for Disease Control and Prevention. May 11, 2023. Accessed May 16, 2023. https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/Improving-Ventilation-in-buildings.html.