Since the COVID-19 pandemic began, healthcare leaders have recognized that respiratory aerosol removal from treatment areas is critical to minimize exposure for both employees and patients. Ventilation (air exchange) rate impacts the length of time that respiratory aerosol particles remain in the air in any indoor environment.
Thanks to a simple and inexpensive process for assessing ACH (air changes per hour), the University of Rochester orthodontic program recently resumed normal operations. Dr. Emile Rossouw, chair of the Division of Orthodontics and Dentofacial Orthopedics at the university’s Eastman Institute for Oral Health, says he has been able to remove patient flow restrictions in the orthodontic clinic for the first time since it re-opened following the 2020 COVID-19 shutdown.
“Achieving the recommended ACH within each area of our facility makes it possible to have all chairs in the clinic occupied at the same time, rather than having to wait 15 to 20 minutes between patients in each chair (due to CDC and NYS Department of Health requirements),” says Dr. Rossouw. “We are back on a regular patient schedule, with physical distancing protocols still in place along with pre-appointment screening. Everyone except patients in treatment continues to wear appropriate PPE.”
While the U.S. Centers for Disease Control (CDC) does not have a ventilation rate recommendation for dental offices, the CDC has set guidelines for surgical procedure rooms in outpatient healthcare facilities. These rooms are expected to have 15 full air exchanges per hour.
With the aim of helping Eastman Institute and other dental facilities meet this standard, a research team under the leadership of Dr. Yanfang Ren studied factors related to ventilation rate. Dr. Ren is a professor, associate chairman and clinic chief in the Eastman Division of General Dentistry.
“We found that carbon dioxide levels in dental treatment rooms are directly associated with ventilation rate and the number of people in the room,” Dr. Ren told the Eastman Institute news bureau. The research team’s ventilation rate calculation method was published in the Journal of Dental Research.
Along with their ACH assessment method, the researchers set up an online interactive calculator accompanied by a list of needed supplies, including a CO2 monitor. Using this approach, dental and dental specialty providers can determine the ACH rate for any room or space – without the need for costly measurement equipment or services.
“The ACH also indicates how many air purifiers will be needed to attain the effective ACH rate of 15 ACH,” says Dr. Rossouw. “To enable our orthodontic clinic to attain this rate, we now have eight air purifiers in the clinic. All of our seminar rooms, the resident room and offices are also equipped with air purifiers.”
Learn more about the Eastman researchers’ method and access the Ventilation Calculator.
Please note that although the preceding story contains one account of a successful usage of ACH to satisfy pertinent requirements, state and/or local requirements may differ by jurisdiction. AAO members are encouraged to consult with their state and/or local health authorities in order to remain compliant with such requirements.
