UVC Air Purification – Live Podcast Part #1

Michael believes that UVC air purification is a valid strategy to disinfect surfaces, but it’s not his first choice for indoor air quality. PCOs also use UV lights, so there can be some confusion between the strategies that use UV light and UVC lights as the lone strategy. UVC lighting is typically less effective in the airstream than on surfaces, though the efficacy also depends on the airstream speed and microbes present. UV lighting in commercial applications also tends to be more precisely engineered than UV add-ons in residential applications.

Over time, UV bulbs lose their intensity over time and require replacement. As such, relying on the manufacturer-determined replacement timetable is recommended, not waiting for the bulb to burn out.

The “Holy Trinity” of IAQ does not focus on surface disinfection, which is what UV lights aim to do. In the case of SARS-CoV-2, the presence of UV lights on the evaporator coil is unlikely to reduce your chances of infection significantly. The virus has a short lifespan on surfaces and cannot reproduce without a host; even a bacterial host on the HVAC equipment likely won’t become a major threat to the inhabitants. Controlling humidity (within reason) might be a more beneficial strategy for controlling viral activity, as viral transmission is typically more likely in dry conditions. However, mites, fungi, bacteria, and other contaminants have varying humidity requirements for growth, and higher-humidity environments that may combat viral transmission may allow fungi to thrive. However, we also have to keep in mind that our understanding of this particular virus is constantly evolving.

Ultimately, the claims that UV lights disrupt the genetic material of SARS-CoV2 may be accurate, but it likely isn’t practical in terms of HVAC and IAQ accessories. Filtration and regular maintenance are also definitely worth our focus, but we simply don’t have definitive facts about their effectiveness against the virus. Before we set standards, we need to have data from third-party peer-reviewed studies. In any case, there are appropriate applications for UVC lights, filtration, ventilation, PCOs, and so on.

Viruses also aren’t “alive” in the same way that bacteria and fungi are, so we do ourselves no favors when we talk about “killing” viruses. Instead, a better long-term strategy could be to improve our home health and safety with other IAQ products, especially filters with high-quality media, so that our immune systems can fight viruses uncompromised.

Bryan and the crew also discuss:

Ozone production
Intensity vs. wavelength
Selling UV lights during the pandemic
Insulation types
Misapplication of UVC lighting
Where NOT to shine UV lights
UVC vs. photocatalytic oxidation
Degradation of surfaces and the release of VOCs
The development of standards from peer-reviewed studies
Probiotic micro-misting solutions
IAQ testing and sales