Dental offices install high efficiency filtration systems

By Ken Kellar

Like many other health organizations in the district, the Fort Frances Dental Centre and Emo Dental Clinic are doing whatever it takes to ensure the safety of their patients and staff.

Following the outbreak of the COVID-19 pandemic and seeing a need to address the health and safety concerns surrounding it, the two dental offices took a “best of the best” approach to keeping everyone safe.

“As COVID kept developing and there was more and more information about how it spread and whether or not asymptomatic carriers could spread the disease, we felt there was a high concern that we could be seeing asymptomatic patients at some point and that could be spreading the disease to staff or to other patients and we just didn’t want to take that risk at all,” said office manager Sarah Wreggitt.

“We’ve always felt like patient health and safety was our number one priority and it just wasn’t a risk that we were willing to take. We did some research and a lot of consultation with different professionals to find out what the best system would be, and that’s where we landed on the system that we did. It has a very high level of filtration and a quick turnaround time so we felt like that was the best for the safety of everyone.”

Wreggitt explained that the system itself is a hospital grade air purifying system that can circulate the air and removes 99.9 percent of aerosols and pathogens in five to eight minutes, depending on the power level it has been set to. The decision to implement it came from a recommendation from the governing body and the health guidelines they released.

“The RCDSO (Royal College of Dental Surgeons of Ontario) who govern the dentists had come out with their original guidelines,” she recalled.

“You were supposed to meet certain standards for all patients that you saw, and they kind of backtracked on that about a week later saying it was only patients that screened or tested positive for COVID that you really had to do extra things for. We just didn’t feel like that was safe because patients could come in and screen negative for COVID, say they’re feeling fine, they haven’t been anywhere and they could be an asymptomatic carrier, so we did implement a few different things.”
Weston Igo, Principal with ABLE Energy Management and Design in Thunder Bay who installed the systems, explained that because the virus is tiny, the new units work on a much smaller scale than even medical purpose masks.

“The Centre for Disease Control (CDC) has recommended that all healthcare workers wear
N95 respirator masks to protect them from contracting COVID-19,” Igo explained.

“The ‘N95’ designation means the respirator is tested to filter at least 95% of test particles measuring 0.3 microns. HEPA (High Efficiency Particulate Air) media has a higher standard of particle filtration than an N95 mask. According to NASA, HEPA media effectively filters nanoparticles as tiny as approximately 0.015 microns in diameter. HEPA filters are highly effective at catching particles much smaller than the average virus. Since the novel coronavirus measures 0.125 microns, this suggests HEPA media is capable of filtering the virus from the air.”

The five to eight minute window is another suggestion from the CDC referred to as “fallow time.” The metric is used to note how many minutes it takes for the filtration system to remove a percentage of aerosols from the room.

“The air change rate is greater than 50 air changes per hour (ACH) in each treatment room,” Igo said. “This reduces the fallow time of 99% to less than 6 minutes and maintains negative pressure in treatment rooms. Every minute the treatment room air is completely exchanged and HEPA filtered.”

Wreggit explained that as it usually takes longer than the five to eight minutes for each room to be turned over for the next patient, each new patient enters a room where the air is completely scrubbed of any aerosol that could have been left over from or generated by the previous patient.

The clinics are also following other stringent health guidelines, which include frequent hand sanitizing, disinfecting high touch surfaces multiple times a day and masks for everyone in the office. Wreggitt also explained that the staff have implemented enhanced PPE measures, which takes things a step beyond masks.

“Enhanced PPE means for any aerosol generating procedures, we wear the enhanced PPE,” she said.

“That includes gowns, N95 masks, face shields. The staff have all been certified fit tested for their N95s to make sure they’re fitting properly, and some are wearing surgical caps as well.”

Staff also change their gowns in between patients in order to keep cross contamination to an absolute minimum. All of these safety precautions are on top of screening patients before they come in for an appointment, with Wreggitt noting that anyone who screens or tests positive for the virus has their appointment or procedure deferred, unless it is an absolute emergency.

While there are still concerns in the wider world around the COVID-19 pandemic, Wreggitt stressed that the staff at Fort Frances Dental Centre and Emo Dental Clinic are doing everything they can to reassure their patients.

“What people maybe don’t realize is that dentistry could be high risk because the aerosols that we’re creating when a patient is in the room,” she said.“So especially for those aerosol generating procedures, that filtration system that we’ve installed clears 99.9 percent of aerosols. We’ve taken every step that has been recommended to ensure their safety.”