(CNN) --The ads are everywhere - germicidal ultraviolet lights that can disinfect surfaces and perhaps help stop transmission of coronavirus. But how well do they work? Maybe not as well as people may ...

A bus being treated with ultraviolet light in Shanghai, China. Although types of UV light are already in use to decontaminate vehicles and indoor spaces, the wavelengths used are dangerous to people.

This is an archived article and the information in the article may be outdated. Please look at the time stamp on the story to see when it was last updated. The ads are everywhere – germicidal ...

Ultraviolet light is part of the electromagnetic spectrum emitted by the sun and can be produced by light bulbs, also. UVC rays are absorbed by the ozone in the Earth’s atmosphere ozone, but rays of ...