Updated by Ryan
One study called ‘Surface Disinfection by Exposure to UV Light’ in the Indian Journal of Medical Microbiology showed that UV light at the same wavelength and power as Uvlizer ‘has efficient inactivation of bacteria up to a distance of 8 feet, and an exposure time of 30 minutes is adequate.’
A distance of 8 feet on each side of Uvlizer means an area 16 feet across. 16 feet x 16 feet = 256 square feet. So, Uvlizer can disinfect around 250 square feet in 30 minutes.