Judy..im not sure what their 'kill rate' is but that is different than their stated (big picture) 66% decline in infections in the hospital rooms. I do understand that in one of mzei trials the rooms were clean and no further infections were seen for 6 months (?) I think after our cleaning.
IF these are metal ions they are using could it be that they end up that those are not environmentally\people friendly (???). Just as metals in the environment from pollution are toxic to humans over time. Not sure if anyone else could shed some light on that. I am not a chemist or anything...JMO