As the COVID-19 pandemic rages on, many heating, ventilation and air conditioning (HVAC) companies are claiming that the ultraviolet (UV) light in their systems will kill coronavirus.
But some HVAC experts believe many of these companies are capitalizing on fear related to the virus and simply taking advantage of customers.
Keith Wortsmith, president of Little Rock’s DASH Heating and Cooling and mechanical engineer, said many HVAC companies and manufacturers claim to have the silver bullet for stopping the coronavirus, and Americans have thrown millions of dollars at them for systems that don’t do what their manufacturers claim.
Many companies claim that the ultraviolet (UV) light in their system will kill coronavirus, but Wortsmith fears that many HVAC UV light installations aren’t following the proper design parameters to be effective inside of an HVAC system’s unique environment.
“UV does deactivate germs and viruses, but it requires the correct germicidal wavelength of UV and enough power to deactivate these germs and viruses in the air stream as they flow through the air ducts,” Wortsmith explained.
Steve Mores, vice president of training and sales and indoor air quality consultant at New Jersey-based Dynamic Air Quality Solutions, said businesses often ask him if he can install UV lighting needed to kill the virus.
“Our commercial clients ask us if having UV lights installed in their HVAC system will kill germs and help control the spread of viruses and bacteria. And I tell them yes, but we will have to design the application and calculate the amount of UV lights required to be effective based on the size of their system. Residential applications are less complicated yet the same design parameters apply” he told Arkansas Money & Politics.
Many companies also offer needlepoint ionization as a solution. With needlepoint ionization, both positive and negative ions are released into the air, where they attach to viruses and other airborne particles, causing them to clump.
“Needlepoint ionization works well in a test chamber, one inch away from a petri dish after 30 minutes of exposure, which is how some of these companies get their great test results, but not in a real life environment,” Wortsmith said. “Ions will clump particles together that carry germs and viruses, yet most filters cannot collect particles in the size range of even these microscopic clumped particles. If ionized properly, many of these clumped particles will also land on surfaces in a home/office and never reach the filter.”
Mores explained that most bacteria are five microns and much smaller in size, while viruses can be 100 times smaller than bacteria.
“So, we are talking about very small microscopic organisms,” he said..” One micron is 150 times smaller than the diameter of a human hair. If these clumped particles and viruses somehow managed to not cling to the wall and other surfaces in a home and somehow made it to the filter, even the best store bought filters don’t have the capability of capturing these fine particles. The clumped particles would pass right through. Even viruses that are clumped together are still too small for filters to collect. And you have to ask yourself the question, ‘If they are taken out of the air, where do they go?’”
Experiment results from laboratories, such as EMSL, showcase what Mores is talking about. When testing the effectiveness of needlepoint ionization’s ability to kill or deactivate a bacteria or virus, the lab test was conducted one inch away from a petri dish, with no airflow, in a small test chamber. In this test the best results showed a 99.6 percent kill rate over a 30-minute period. The rest of the experiments, carried out on a wide range of bacteria and viruses, showed success rates from 69 percent to 99.7 percent in a period of 30 to 60 minutes. Although these are excellent results, in an HVAC system the air carrying viruses and bacteria is moving very fast, so to achieve these same results as reported the bacteria or virus would have to stop in front of the ionizer, one inch away, for 30 minutes, and that’s not the case in real world application.
“These results cannot be properly extrapolated to apply to the real world HVAC environment. The airflow in an HVAC system is moving at nearly 500 feet per minute,” Mores said. It may be the right technology, yet it’s the wrong design for an HVAC application. “It’s the equivalent of lighting a match, observing that it’s hot enough to burn your hand, and trying to sell it to people for the purpose of heating a whole house. It’s the right technology, heat, but it’s the wrong design, not enough heat,” Mores said. “It’s the equivalent of lighting a match, observing that it’s hot enough to burn your hand, and trying to sell it to people for the purpose of heating a whole house.”
“I think that some contractors genuinely don’t know how to read these results and don’t know how misleading this can be,” Wortsmith said. “But I do believe that some contractors are aware– they just don’t care.”
A few manufacturers have claimed that their product has the ability to kill coronavirus.
“Do you really think that the government is handing out test tubes of coronavirus to anybody who requests it for a test?” Mores asked. “I know that UV light with enough intensity can deactivate the coronavirus, even in the HVAC air stream, because it has successfully deactivated all other viruses known to man to date. So, it is very plausible to predict that it will deactivate the COVID-19 coronavirus as well. But until we have the opportunity to test in a lab, we can’t make the claim that it does.”
Mores shared test results from a California laboratory, Innovative Bioanalysis, that did manage to conduct an experiment on an ionizer product being tested on a sample of COVID-19, yet once again in a small test chamber.
“If we take this at face value, they put two ionizers in a small 1 cubic foot test chamber which filled the chamber with super high levels of ions,” Mores said. “It still took 30 minutes to achieve the reported results on a stagnant stainless steel surface, not real world moving in the air flow in an HVAC unit.”
Wortsmith and Mores both advise consumers to do their own research.
“Ask lots of questions,” Wortsmith said. “A lot of people just want to make a sale.”