Sawyer’s water filters contain a high number of tiny U-shaped hollow fiber microtubes that trap contaminants while allowing decontaminated water to freely pass through at a high flow rate — eliminating the need to store water and reducing the possibility of water contamination after the filtration process.
Each filter is certified for absolute microns; that means there is no pore size larger than 0.1 in size. This makes it nearly impossible for harmful bacteria, protozoa, or cysts like E. coli, Giardia, Vibrio cholerae, and Salmonella typhi (which cause Cholera and Typhoid) to pass through the Sawyer Mini.
Sawyer filters have been tested by independent and qualified research laboratories and found to remove 7 log (99.99999%) of bacteria and 6 log (99.9999%) of protozoa, exceeding US EPA standards. The filter does not remove chemicals, dissolved solids, or viruses. However, viruses are very rarely found in North America or when travelling to foreign cities.