Proctor and Gamble, a U.S. company that has a presence in almost every American home, manufactures a diverse set of products ranging from toothpaste and shampoo to disposable wipes and prescription drugs. But since 2004, they have also been sharing clean drinking water with the world. Under the moniker of their PUR brand, a brand that encompasses drinking water filters for sinks, refrigerators and pitchers, P&G has been distributing packets that can purify almost any available water even if that water is contaminated with deadly microorganisms.
Quite simply, one only needs to pour a PUR packet into a container filled with water, stir, filter the resulting water through a cloth strainer (provided in each packet) and wait about 20 minutes. The results are amazing even the most turbid, fouled water becomes clear and free of disease in less than 30 minutes, start to finish. Each packet can purify 10 liters of water and the process removes silt, cysts and pollution; additionally it kills viruses and bacteria that cannot be easily filtered. In the image below, the process of separating the solids from the water can be observed. This image was taken after a packet was added to brown, filthy water. The stirring process begins the reaction and the solids begin to clump together and fall out of the water.
While the obvious beneficiaries of such water-purifying technology are the citizens of the developing world, there are many other needs. Post-disaster recovery efforts like those after a major hurricane or earthquake can greatly benefit from clean water. Bringing in water from distant sources is a time consuming and resource-intensive effort; with adequate on-site water purification, it is possible to divert these resources to other important tasks like transport and care for the injured and cleanup. Beyond the grim vision of a disaster, hikers and backpackers are always eager to have a lightweight, transportable means of water purification.

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