Owners install filtration systems to limit potential COVID-19 spread

Judith Lyons-Picard was diligent as she prepared to reopen her Candler business, The Lyons Mane Salon, at the end of May.

She stocked up on personal protective equipment. She purchased disinfectants to use on the salon’s surfaces. And then she got to thinking: Was there a way to not only disinfect surfaces, but to disinfect the air? 

Her close friend and local orthodontist Tim Scanlon told her about a new air sanitation system he had recently installed in his three Western North Carolina offices. Intrigued, Lyons-Picard forked over $1,500 to add an ionizing device to the salon’s heating and cooling unit. 

“It was a no-brainer for me,” Lyons-Picard says. “The vast majority of the people who come into my business fall into what one would consider a high-risk category for COVID-19. And as a business owner, I don’t want people to be afraid to come into my business.”

Despite a lack of definitive evidence that COVID-19 can spread through heating, ventilation and air conditioning systems, residential and commercial property owners are increasingly looking for ways to preemptively protect themselves and their customers from potential airborne transmission. “It helps make everyone feel more comfortable,” Lyons-Picard says. 

Increased demand

COVID-19 is primarily transmitted through droplets spread by speaking, coughing or sneezing, according to the most recent set of guidelines released by the World Health Organization. Emerging research suggests that some cases of the coronavirus result from airborne transmission, which occurs when small virus particles linger in the air — and drift farther than the 6 feet of distance health officials recommend to limit contagion. 

Despite isolated anecdotal occurrences, including infections traced to a restaurant in China and a choir practice in Washington, there is no strong evidence to suggest that well-maintained air conditioning, ventilation or other type of climate control systems contribute to the spread of COVID-19, according to a joint report released in May by the WHO, the World Meteorological Organization’s Joint Office for Climate and Health and the U.S. National Oceanic and Atmospheric Administration. 

To limit viral spread, the group recommends cleaning air systems and ducts regularly and making sure rooms are well ventilated, in addition to preventative measures like wearing a face covering, social distancing and disinfecting surfaces on a regular basis. The U.S. Environmental Protection Agency suggests increasing ventilation with outdoor air as well as air filtration, using a portable air cleaner and continuously running an HVAC system to increase air flow.

Nonetheless, the demand for various types of air filtration systems has significantly increased since North Carolina reported its first COVID-19 case in March, says Duane Gentry, president of the Gentry Service Group. The number of residential installment inquiries his company has received for the systems has doubled, he said, and commercial installation requests have “gone up tenfold.” 

According to Gentry, three methods for filtering viruses and other particulate matter from the air are being widely deployed: ionizers, ultraviolet lights and specialized air filters. 

Ionizers send an electrical charge to molecules in the air, killing viruses and bacteria. The electrically-charged ions cause particles to clump together and settle on surfaces, instead of entering a ventilation system. These ionizing systems work well in larger spaces, Gentry says, and generally cost $1,200-$1,500 for residential uses. 

He estimates that Gentry Service Group has installed 75 to 100 ionizers in residential properties and 10 to 20 in commercial spaces each month since March.

Ultraviolet lights are mounted inside a heating and cooling system, where they shine concentrated light on the system’s coils, killing any viruses or bacteria before the particles can enter the airstream. The systems are effective at killing “what it can see directly,” notes Travis Hyatt, heating and cooling service division manager for MB Haynes Corp. UV purification systems typically run about $400-$600 for residential spaces; costs rise for commercial application. 

Thicker air filters with a higher minimum efficiency reporting value, or MERV, can also help trap smaller particles before they make their way into an HVAC system — but the recommended filters with a MERV rating of 13 or higher create a drag on air systems and can cause damage to the equipment, Gentry cautions. These filters should be changed at least once a month. 

Industry applications

Air filtration isn’t a new topic for hospitals, which have long focused on ways to mitigate the spread of infectious particles within their facilities. With the onset of COVID-19, AdventHealth Hendersonville installed a negative air flow intake area using air scrubbers with HEPA filtration to exhaust the air, explains Victoria Dunkle, hospital spokesperson. 

Pardee UNC Health Care in Hendersonville utilizes more than 40 different air systems in its main hospital alone, says Kris Peters, Pardee’s vice president of support services and systems integration. The hospital uses MERV-15 and above for all filtration; so far, the facility hasn’t installed any new systems in light of the pandemic. 

School systems have also been calling about added filtration methods, Hyatt says. But because schools have so many heating and air conditioning units — and are often operating on a fixed budget — determining a cost-effective solution can be a challenge. 

The air filters at all 42 Buncombe County schools were changed before students and staff returned to the classroom, said Tony Baldwin, Buncombe County Schools superintendent, at an Aug. 13 press conference. Asheville City Schools contracted with a private HVAC engineering group to analyze all its air-handling systems and installed MERV-13 air filters in all units, added Shane Cassida, Asheville City Schools assistant superintendent for auxiliary services, at the same press conference.

“I think all of us have to be cognizant that our buildings are all different structures and ages,” Baldwin said. “Those systems, likewise, present challenges. So we’re looking at what we can consistently do across the entire district, and these are the measures we can take this fall.” 

Businesses adapt

Peter Montague, co-owner of the downtown restaurant Zambra, was visiting family in Florida when he ran into an old friend who distributes air purification systems to hospitals around the country. After talking, Montague decided to install one of the S400 air purification units — which uses a HEPA filter and UV light to kill and remove viruses — in his restaurant, as well as an ionizer in his HVAC unit. Montague now sells the S400 air purification units on the side. 

“I think overall, people are happy to see businesses going the extra mile to do anything to show that they care, that they are going above and beyond to make sure the guests and staff are safe — especially indoors,” Montague says. “A significant portion of our business is indoors, and I want my staff and the people that come in to feel safe.” 

Orthodontist Tim Scanlon of TS Orthodontics decided to install a MERV-13 filter, an ionization unit and a UV purifier in each of his three office locations in late May. In total, the cost for the equipment came in at close to $40,000, he says, but the payoff is the peace of mind that comes with knowing those who enter his practice are breathing clean air.. 

When Robert Tipsword, owner of Zia Taqueria, contemplated installing new air filtration systems, the decision came down to two concerns: the length of COVID-19 exposure, which early research by the Center for Evidence-Based Medicine shows can determine how sick a person gets and the number of people who could be infected by one exposure. 

An ionization system claiming to be 97% effective in stopping the spread of COVID-19 was installed inside the restaurant the week of Aug. 17, Tipsword says. 

“As far as if that’s 100% true, I just don’t know — it seems like we’re all searching for the truth these days,” he says. “But we’re just trying to do the best we can and go the safest route we can and do everything in our power to make everyone feel as comfortable as possible.”