November 23, 2020

The Clean Water Institute of Calvin University certifies that it is possible and expected thatSawyer tap water filters can filter over 500 gallons of water in less than 24 hours. We base this conclusion on experimental evidence collected wherein all three filters tested were each able to filter over 500 gallons of water in less than twelve hours. As these three filters were out of their original packaging, we conclude that it is reasonable to expect that any Sawyer tap filter will likewise be capable of such capacity.

This certification does not claim that all Sawyer filters under all conditions will be able to filter 500 gallons of water in less than 24 hours. If the filter is not used as prescribed by the instructions, or if the water is sufficiently dirty, or if the water pressure is too low, or if the tap diameter is too small, then it may not be possible to filter 500 gallons in less than 24 hours. Our tests were conducted with municipal tap water, on a 20 mm (outer diameter) tap, and with sufficient water pressure to achieve at least 5 gallons per minute of flow. The details of our work are presented on the attached page.

Download the report to learn more.