The U.S. Centers for Disease Control and Prevention recently made significant updates to its ventilation guidance to help curtail indoor transmission of the COVID-19 virus, CNN and other outlets report.
“The updated CDC guidelines represent a renewed focus on the importance of indoor air quality for building trust and inviting employees back to the office,” Joanna Frank, president and CEO, Center for Active Design, operator of Fitwel, and president and CEO, Active Design Advisors Inc., told Connected Real Estate Magazine. “Prioritizing health is no longer a reactive market trend, but a business imperative that represents both a risk and an opportunity for the real estate industry. Tenants are demanding quality office spaces, and companies who engage in these efforts will set themselves apart and get a leg up on attracting and retaining talent through market differentiation.”
Among the updates, the agency has recommended five air changes per hour regarding how much rooms and buildings should be ventilated.
“When possible, aim for five or more air changes per hour (ACH) of clean air to help reduce the number of germs in the air,” the CDC said. “Rather than a hard-and-fast rule, the five ACH target provides a rough guide to air change levels likely to be helpful in reducing infectious particles. For example, increasing ventilation from two to five ACH substantially reduces the time to remove airborne contaminants.”
The announcement came one day after the U.S. ended its COVID-19 public health emergency. Indoor air quality experts had been lobbying for change for years to get the CDC to recognize how critical ventilation was to help control the pandemic, CNN reports.
“I am pleasantly surprised to see CDC add this guidance,” said Kimberly Prather, an atmospheric chemist at the University of California at San Diego and the Scripps Institution of Oceanography. “I do find it ironic that they finally published ways to end the pandemic at the same time as declaring it is over.”
In May 2020, Prather co-authored a perspective article in the journal Science that explained the airborne spread of COVID-19. Prather and more than 200 other scientists also wrote a letter to the World Health Organization and other public health authorities asking them to acknowledge and develop guidance to stop airborne spread later that year.
“If they had broadcast and implemented these changes at the beginning, there never would have been a pandemic,” Prather said.
Joseph Allen, director of the Harvard Healthy Buildings Program, also celebrated the CDC’s new ventilation recommendations.
“It’s a monumental shift,” he said.” We haven’t had this. We haven’t had health-based ventilation standards.”
Allen also noted the guidance will also help with other airborne hazards such as allergens, wildfire smoke and non-COVID infectious diseases like the flu.
The CDC developed this new guidance with a new standard from the American Society of Heating Refrigeration and Air Conditioning Engineers, CNN reports. The agency noted that improved indoor ventilation can decrease the concentration of viral particles in the air. This can reduce the chances of some breathing in the particles and getting sick.
Additionally, better ventilation can lower how much of a virus someone could inhale. Bringing the amount of virus down could also decrease a person’s infectious dose and impact how severe their infection ends up being.
The CDC’s guidance also provided detailed recommendations to improve a building’s indoor air. Some examples were as simple as opening doors and windows to increase outdoor airflow. The agency also suggested opening outdoor air dampers on HVAC equipment beyond minimum settings to reduce or eliminate HVAC air recirculation when weather permits.
Cleaning indoor air was also among the CDC’s recommendations. Building owners should upgrade their HVAC filter efficiency to a Minimum Efficiency Reporting Value (MERV)-13 or better.
“When compatible with your HVAC system, increased filtration efficiency is especially helpful when enhanced outdoor air delivery options are limited,” the CDC said.
Building owners might also find air cleaners or purifiers helpful if they use high-efficiency particulate air (HEPA), CNN reports. These tools are especially crucial in high-risk areas such as schools and medical offices, according to the CDC.
“Key strategies, from ventilation and filtration upgrades to performance testing, allow building owners to be transparent with occupants about how their spaces are supporting health and well-being,” Frank said. “Even as the COVID-19 state of emergency comes to a close, maintaining indoor air quality remains essential to supporting employee productivity, reducing sick building syndrome and absenteeism, and signaling to tenants that health and safety remain a top priority.”