UV light sits somewhere on the electromagnetic spectrum between visible natural light and X-rays. UV radiation is invisible to the human eye but its effects can regularly been seen in the way of sunburn or sun damage to our skin after prolonged exposure. UV light that is used within UV disinfection systems is set at a particular wavelength causing the breakdown and rearrangement of the DNA of any micro-organisms it comes into contact with. The rearrangement of the microorganisms DNA prevents it from reproducing and therefore preventing it from infecting or allowing for it to be contracted from one living being to another.