While it has long been known that ultra violet (UV) radiation can kill many kinds of bacteria, UV light intensive enough to do much good in hospital settings is damaging to human eyes.
Recent studies have shown that high intensity narrow spectrum (HINS) visible wavelength light, not UV, centered on the 405 nm wavelength is both effective in killing MRSA and a range of other bacteria in patient rooms, it is also safe for human exposure without special protection.
The HINS LED lighting tested is effective in greatly reducing the possibility of infection from various gram positive and gram negative bacteria as well as some fungi.
Adding other LEDs producing different visual light wavelengths can make this into a standard lighting system for hospital rooms.
See the following article for a list of the bacteria and fungi shown susceptible to HINS UV light.
Clinical trials were conducted at the Glasgow (Scotland) Royal Infirmary.