I don't dispute that UV kills germs and viruses. What I have been saying is that the wands are not practical. They are prone to operator error and inpatients. Depending on how strong the UV output is on a single small diode, which generally is not much in a battery powered portable wand, it would take around 3-4 minutes to disinfect, say a steering wheel. One would be MUCH better off to simply use an alcohole or bleach based disinfectant.