HVAC Contractors Use UV To Help Control Spread of COVID-19 Virus

Life has been crazy amid the COVID-19 pandemic. Unemployment hit 14 percent in May, the highest since the Great Depression. More than 30 million people were furloughed, prematurely retired or no longer employed. Tens of thousands of Americans have died from COVID-19 complications and more than 1 million have contracted the virus.

UV Light in HVAC Systems to Kill Viruses

Life has been crazy for the HVAC industry too, but in a more positive way. HVAC contractors and manufacturers associated with ultraviolet germicidal irradiation (UVGI) equipment are logging record sales figures.

UV has made an inroad to the HVAC industry the last two decades via air handlers and ductwork. UV lights are proven in studies to have a 99.9-percent kill rate, or inactivation, of bacteria, mold, viruses and other biological contaminants. HVAC contractors use the technology in the form of UV light kits positioned near evaporator coils, which attract microbes with their dark, wet environment. The UV lights also keep the immediate interior cabinet surfaces free of biological growth.

The fact that UV, specifically the UV-C wavelength of 254-nanometers, kills viruses has thrown UV-C technology for HVAC systems into the limelight during the COVID-19 crisis. Because of its sudden emergence, there’s no published data of UV-C’s effectiveness or dosage for inactivating COVID-19. However, the 2004 study “Inactivation of the coronavirus that Induces Severe Acute Respiratory Syndrome, SARS-COV” published by the National Center for Biotechnology Information (NCBI). It has proven UV-C’s success with other coronaviruses, such as SARS. Although dosages are critical and undetermined at this point, experts believe COVID-19 dosages are probably similar to SARS for inactivation.

Fresh-Aire UV’s third-party testing found UV-C similarly effective with all viruses. One study simulated airstream microbe inactivation in an ASTM/AHAM style environmental test chamber simulating a typical building’s indoor environment and HVAC air handler arrangement. Performed in an ASHRAE Standard 52.2 test duct system, the test’s UV-C light singlepass results demonstrated a 99.03-percent inactivation of the virus (MS2 coliphage).

UV Used in Response to COVID-19

With no known cure or vaccine, UV-C has been a potential solution for inactivating COVID-19 on surfaces and in HVAC airstreams. Consequently, recent news of UV-C, even though it has been inactivating viruses for decades, has gained significant interest among consumers, doctors and healthcare administrators since February.

For example, hospitals overwhelmed with COVID-19 patients amidst a personal protective equipment (PPE) shortage last March developed their own innovations to disinfect and reuse employee N95 masks and other medical protection. “Doctors and healthcare managers are ordering UV-C lamp systems to convert hospital refrigerators, cabinets and other containers into make-shift disinfection chambers for the renewed interest in reusing PPE due to shortages,” said Aaron Engel, vice-president business/development, Fresh-Aire UV, a Jupiter, Florida-based manufacturer of indoor air quality (IAQ) equipment, such as UV systems for HVAC units, ductwork and environmental surface disinfection systems (ESDS). “Since the chambers are a variety of volumetric sizes, we take their dimensions and provide the most effective UV output using our proprietary BlueCalc modeling software.”

Puzzled how doctors were making the connection of UV-C’s virus inactivation capabilities with PPE disinfection, Fresh-Aire UV executives soon discovered the Centers for Disease Control and Prevention (CDC) had issued its guideline document “Crisis Standards of Care Decontamination Recommendations” on April 9. One recommended alternative cited a 2018 American Journal of Infection Control article “Ultraviolet Germicidal Irradiation of Influenza-Contaminated N95 Filtering Facepiece Respirators (FFR)” to disinfect PPE for reuse. The 2018 article’s researchers custom-built a deactivation chamber using Fresh-Aire UV’s high output UV-C lamp system. The conclusion stated that one to five-minute (depending on chamber size) UV-C exposures were effective in disinfecting N95 respirators for reuse during pandemic shortages.

Now Fresh-Aire UV is introducing its own Blue-Cube disinfection chamber designed specifically for healthcare PPE and healthcare tools and accessories, such as stethoscopes.

Doctor Gives a Thumbs Up

A doctor gives a thumbs up for a Purity HEPA/UV portable room purifier.

Growth in Demand for UV Systems

UV-C rise to prominence during the COVID-19 crisis didn’t surprise contractor, Brian Stacy, vice president, Trinity UV Lighting, Trinity, Fla., because the seven year old company’s niche is UV. Last March and April sales were up 300 percent over the same 2019 period, according to Stacy, a 10-year veteran of the industry, who also has a patent for a UV system for disinfecting ambulance patient cabs.

Trinity’s most popular requests during the pandemic have been environmental surface disinfection systems (ESDS) to maintain surface areas free of biological contaminants and UV lamp kits for disinfecting the airstream, coils and interiors of HVAC air handlers.

The ESDS units are typically ceiling hung lamps in fixtures that disinfect an entire room’s surfaces and objects after occupancy. UV can injure occupants, so ESDS systems require safeguards, such as timers, filtered viewing windows and cut-off safety switches if someone enters the area. Typically Trinity’s systems for operating rooms and waiting rooms are scheduled for disinfection after hours or on-demand in between patients.

Commercial businesses that temporarily closed during the March or April COVID-19 lockdown took advantage of the downtime to retrofit air handlers with UV, according to Stacy. The UV lamps keep the coil and the surrounding HVAC cabinet’s interiors free of mold, but also inactivate airborne bacteria, viruses, allergens and other biological contaminants as they pass through the UV field. One commercial client had twin office buildings with several 50 to 100-ton HVAC systems supplying a total of 300 to 500,000-cfms. Trinity outfitted each unit with UV lamp kits. With hundreds of workers’ health at risk when returning to work, the units’ disinfection efforts promise to kill return air biological contaminants, including COVID-19 if it’s present, before supplying conditioned air back into the spaces. During post-COVID-19 periods, the airstreams will continue to inactivate annual influenzas, allergens and other contaminants while upgrading the facilities’ general indoor air quality (IAQ).

Other UV lamp kit and ESDS projects for commercial HVAC systems during the pandemic have included eye surgeons, general physician waiting rooms and offices, and assisted living facilities.

While Trinity UVC Lighting’s have steadily increased since February, inquiry emails and phone calls exploded the day after a televised White House Coronavirus Task Force press briefing on UV’s effects COVID-19 by Acting Under Secretary, William Bryan of the U.S. Dept. of Homeland Security’s research and development arm, the Science and Technology Directorate (STD). After initiating research last February, the STD’s studies arrived at the conclusion that COVID-19 is inactivated within a minute once exposed directly to the sun’s UV rays outdoors.

The press conference also inspired consumers to check online for the dozens of trials and white papers proving UV’s general effectiveness with bacteria and viruses. The sun’s rays consist of 95-percent UV-A and five percent UV-B and can kill COVID-19 with enough exposure time, according to the STD. In retrospect, UV-C is the shortest and most lethal of the three wavelengths at 254-nanometers. Microbes can’t adapt to UV-C because they have no previous exposure or mutation to it, because it’s filtered out by the upper atmosphere and doesn’t reach the earth’s surface.

“Things got crazy after that press briefing,” recalls Stacy. “People were seeking me out from Internet searches on UV. There were a lot of phone calls with questions. People that were on the fence, finally jumped into UV after that. Not a lot of people know about UV, but something like a televised press conference in the middle of a pandemic gets consumers’ attention. The press conference increased Trinity’s residential demand. For residential customers’ air handlers, Trinity installs either single UV lamps or Fresh-Aire UV’s APCO, a combination UV and activated carbon media catalyst air treatment system that won the AHR Innovation Award for IAQ at the 2011 AHR Expo.

Stacy said UV works and the benefits far outweigh the costs. However, it has to be sized and installed properly. Dosage is important for proper inactivation time and efficiency, therefore he uses either Fresh-Aire UV’s Blue-Calc or his own inhouse calculation software.

Medical staff with Blue-Cube

Nurses and doctors with the recently introduced Blue-Cube UV PPE disinfection chamber that was inspired by doctors in March who ordered UV lamps to convert microwaves and refrigerators to disinfection chambers during shortages

Surgery Room at St Lukes using UV

UV germicidal irradiation light systems used to disinfect surgery rooms at St. Luke’s Cataract & Laser Institute in Tarpon Springs, FL

UV disinfection in commercial air handlers

UV disinfection in commercial air handlers

Brian Stacy

Brian Stacy, contractor and vice president of Tinity UV LIghting outside the business of a client



UV Presents Potential New Revenue Stream

Many HVAC contractors are on a record pace to sell and install residential UV systems through the COVID-19 crisis. Distributors have also seen an unprecedented interest in UV. Some contractors have taken a proactive marketing approach to educate consumers on UV and its benefits on general IAQ.

“Our UV sales are up 1,000-percent due to COVID-19 and inquiries are continually increasing,” said Ronald Zajack, president, Coastal Cooling Inc., a Fort Myers, Florida-based HVAC contractor. Coastal has promoted UV with TV commercials, an email blast explaining UV’s benefits and the company’s policy on protecting customers and employees during service calls, and an instructional video post on its website.

Likewise, UV sales for Action Furnace, Calgary, Alberta, surged 85-percent throughout March, April and May, according to Eric Parcels, service manager, who attributed the increase to Alberta’s 6,400 confirmed COVID-19 cases and 120 deaths through mid-May.

Parcels didn’t anticipate a pandemic, but coincidentally was already developing an IAQ niche for the 45-year old residential HVAC contractor. For the past year the company had been adding products such as UV lights, based on Parcels’ previous experiences promoting UV disinfection products with his former HVAC contractor employers in Ontario and Florida. Consequently, the year-long IAQ niche preparation put the company and its two other branches in Edmonton and Red Deer in the right place at the right time when COVID-19 news hit Alberta in late February.

Fortunately technicians in the company’s fleet of 25 service and maintenance vehicles were ready to install and promote UV products when consumer interest increased during COVIC-19. Crews install two types of UV systems. One is a single low-voltage one-year or two-year UV bulb installed near an air handler’s evaporator coil. Customers opting for a more comprehensive system get an APCO, manufactured by Fresh-Aire UV, Jupiter, Fla. The APCO-x, for example, combines UV for inactivating biological contaminants and lifetime activated carbon-ceramic media for adsorbing gaseous airstream contaminates, such as VOCs.

Action Furnace is promoting UV as a disinfectant for viruses, but is cautious about naming COVID-19 specifically, because there are no studies yet proving UV’s effectiveness inactivating the virus. However, there are ample studies proving UV’s effectiveness against viruses and similar coronaviruses such as SARS and MERS. Therefore, the company promotes IAQ in general with 30-second radio spots and mailers to customers. “We don’t mention COVID-19, but we do mention studies that have proven UV 99.9-percent effective against viruses,” said Parcels.

Action Furnace has also trained service techs to promote IAQ using a 30-minute air quality monitor collection process executed during routine service calls. A summarizing read out informs customers the amount of non-biological contaminants found in the household’s air, such as CO2 or VOCs. The air analysis helps customers decide whether an air treatment system would be effective for them. The readouts are later recorded on customer invoices for follow up during the year. Action Furnace has stocked the monitors on five of its 15 service trucks and hopes to fully roll out the program to the 10 remaining service vehicles along with five maintenance trucks.

The chaos of COVID-19 has kicked UV interest into high gear for commercial facilities and has spurred a new curiosity in IAQ among consumers. Meanwhile, manufacturers and distributors are hustling to keep product supply chains full and product innovation on a keen level. Combined with the general public’s adherence to social distancing, hand washing, masks and other safeguards, COVID-19 will hopefully be retired as just another pandemic that came and went.