Does UV Light Kill Viruses & Germs Like COVID-19

Can a UV light be used to disinfect your house? Should I buy one to disinfect my Scripps Ranch Dental office?

The answer to that is a big NO.

My Experience Working with UV Lights

Back in the days I use to work in a cancer research facility, and we used UV light to disinfect the hoods for testing different lines of cancer cells. It was imperative to keep the cell lines free of bacteria because even if one got into the solution, it would kill all the cells. We would work under a hood, and only your clean, covered hands could fit inside. The hood had a HEPA filter to keep out any bacteria. 

At the end of the day, we would turn on the UV light and leave it on overnight. Before we turned on the UV, we would close the hood, which had a protective UV blocker to prevent the UV from escaping. We all knew that UV causes cancer, and it takes a long time under high intensity before it would kill any microorganism. 

Can UV Lights Kill the COVID-19 Virus? 

There have been many new UV lights on the market claiming to kill the COVID-19 virus or at least disinfecting surfaces. There are three forms of UV rays: UVA, UVB, and UVC. 

UVC is the only form of UV light that will kill COVID-19. Lets first go over what we know about the different forms of UV lights.

UVA Lighting
UVA is the majority of UV light that penetrates our atmosphere. It is responsible for the aging of skin. It can damage the cell DNA and can potentially lead to skin cancer. Research on SARs, a relative of COVID-19, showed that exposure of the virus to 15 minutes of light had no impact on the virus. Exposure to high levels and for long durations may be effective on surfaces. The exposure duration is so long that it is not a viable form of disinfectant warranting more research.

UVB Lighting
UVB is responsible for sunburns. It can damage the DNA of cells and is mostly likely the cause of all skin cancers. Initial studies have shown UVB to be ineffective against viruses. Or, once again, massive exposure and durations may be required.

UVC Lighting
UVC is the third form of UV light. Fortunately, it’s blocked by our Ozone layer. It will destroy genetic material of a virus as well as your skin. Studies on COVID-19 has shown it to alter the genetic make-up of the virus, not killing it but altering it enough so it will not replicate. In other words, rendering it inactive. Unfortunately, the highest dose of UVC is required to alter the virus. This level of UVC is enough to get a sunburn in just a few seconds.

There is another form of UVC light called UVC-FAR, which requires a much lower dose and is effective against COVID-19. Unfortunately, the lights available on the market do not utilize this form of UV. Only large machines requiring a massive investment can possibly be effective. These lights are generally used by hospitals to disinfect unoccupied rooms. This light is not as destructive to human skin but is not without damage.


There has been a run on UV lights, and most manufacturers are on backorder. Lighting that utilizes UVA and UVB has not shown to be effective on COVID-19 but can cause genetic damage. The dose required for the lights to alter the virus to non-infective levels is extremely high if effective at all. UVC light is effective but requires massive dosages. The slightest bit of it coming into human contact would kill any cell. UVC-FAR lights are the only effective lights and can only be produced by massive hospital type machines that are not available to the general public. So, to summarize the information above, no, you can’t get a UV light that will be effective against COVID-19, and I won’t be getting one for my Scripps Ranch Dental Office due to a lack of reputable dealers that will sell one to us.