I have corresponded with the Aquatabs folks in Ireland, and they have deemed the expense of obtaining EPA approval too high and no potential U.S. distributor has expressed any interest in doing so. The active ingredient is, as I understand the chemistry, essentially the same as Chlor-Floc, which is EPA approved, and other products with this active ingediant are used for pool water and community water disinfection, but it apparently doesn't matter as far as testing is concerned, or some such thing. (I am not a chemist mode) As far as I can tell, the U.S. is the only country that these tabs are not approved. As for the military, that is the government and they rarely have to obey the rules the rest of us must obey.