With the current health situation, a new market has developed: household UV lamps. Presented as the solution to kill viruses, and in particular Covid-19, these lamps can in fact be extremely dangerous to your health. We explain why in this article.
How many UV rays exist?
There exist three types of ultraviolet rays, each distinguished by their wavelength:
- UVA (400 – 315 nanometers)
- UVB (315 – 280 nanometers)
- UVC (280 – 100 nanometers)
Only UVAs and UVBs are able to cross the ozone layer and reach us. they are notably responsible for immediate tanning and sunburns. UVCs,on the other hand, are entirely filtered and are therefore unable to reach us.
For more information on ultraviolet rays, we have an article entirely dedicated to the topic.
What is the problem with household UV lamps?
UVC rays are capable of eradicating viruses, bacteria and other pathogenic germs,whereas UVA and UVB rays are not. Devices sold to the general public are usually UVB rays or poorly-communicated UVC rays.
Household UV lamps are incapable of eliminating viruses, and in particular the SARS-CoV-2 virus, which causes Covid-19. Indeed, neurobiologist Martinez-Romeo states that “Scientific studies have determined that it takes between 5 and 10 minutes of UVC exposure to achieve 100% Covid-19 inactivation.” Yet, many lamps sold on the market argue that it would take only 5 seconds to render objects and surfaces entirely devoid of pathogenic germs.
In fact, we know that in order to use a UVC device several factors come into play:
- The duration of exposure;
- The intensity of exposure to UVC rays;
- The wavelength of UVC radiation.
Household UV lamps are therefore ineffective in eradicating viruses from surfaces. In addition, because of the general public’s lack of knowledge and usage, they can also cause a great deal of damage to health.
You will find more information on UVC disinfection in this article.

What are the effects of UVC rays on our health?
UVC rays are generally used for medical purposes (and more recently, for professional purposes), and there is a clear reason for this.
UVCs are capable of modifying the DNA and RNA of target cells to prevent them from entering the phase of cell division and thus of reproduction. In particular, they affect a component called Thymine, which is part of the four nucleic bases of our DNA. If its transformation differs because of over-exposure to UVCs, it then becomes responsible for the development of a rare genetic hereditary disease as well as skin or eye cancer.
In addition, several studies show that over-exposure to UVCs could cause significant burns and risks of melanoma depending on the number of burns received during exposure. As well as severe damage to the skin and eyes. (1,2)
Finally, the Health Directorate states “At this time, we do not recommend the use of “UV cleaners” for the decontamination of potentially contaminated objects.” Opinion also shared by the WHO (3) which explains that the best way to protect yourself from viruses when at home is to wash your hands with hydroalcoholic gel or soap. The use of household UV lamps could cause serious skin problems and severely damage eyes.
Other devices such as air purifiers can also be ineffective and cause air quality degradation.