sachets Two types of water were used to test the POU solutions in the laboratory:
1) model surface water (EPA#1), which is a very low turbidity matrix, and
2) model-stressed surface water (EPA#2),which was selected from the United States Environmental Protection Agency (EPA) protocol for the evaluation of microbiological water purifiers (EPA, 1987). To produce both matrices, 100 mL 10%sodium thiosulphate was added to 10 L municipal tap water to eliminate free chlorine (FRC