Our UV-C device powerfully disinfects both surfaces and the air. While direct exposure is most effective, the light reflects off surfaces and "bends" to cover more than just areas with direct exposure. The ability to kill an organism is a function of the strength of a UV-C ray and the duration of exposure. So, by running our units for the appropriate length, you will be able to disinfect areas that are not directly exposed.
If a room has many obstacles, such as big objects that block light, we recommend running two shorter cycles in diagonal spots in the same room to reduce shadowing. However, the name of the game is risk reduction, and the high-risk areas are the ones that will be exposed to light (e.g. top part of a table vs behind a couch).