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Treating Hardness in Drinking Water

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Treating Hardness in Drinking Water Did you know . In addition to softening water, some salt- based softeners can help reduce barium and radium in water. If either of these is present in your drinking water, look to see if your softener is certified to NSF/ANSI 44 for reduction of these compounds. Treating Hardness in Drinking Water If you have white buildup on the end of your faucets or scale Options for Treating Hard Water forming on shower walls or doors as water evaporates, you probably have hard water. Wherever water hardness is a concern, water softening is frequently used for treatment. The most common systems Hard water contains high mineral content that is formed as contain a cation exchange resin, which attracts dissolved water travels through rock formations containing calcium and positively charged ions like calcium and magnesium from the magnesium. It is a common problem throughout much of the water as the water flows past the resin. The resin does need to United States as well as other parts of the world. Hardness is be regularly backwashed with a sodium or potassium chloride usually measured either in milligrams per liter (mg/L) or grains solution to regenerate. This is during what is known as a per gallon (gpg), with water containing over 180 mg/L (or 10 backwash cycle where water that contains the excess sodium gpg) being considered very hard water. or potassium chloride is discharged. These systems can also be effective at reducing barium or combined radium (Radium 226/228). Many salt-based water softeners have been verified to meet American national standard NSF/ANSI 44 – Cation Exchange Water Softeners. This standard not only verifies the ability of a softener to reduce hardness from 20 gpg to less than 1 gpg, but also helps ensure that the internal surfaces are safe for contact with drinking water and that the system is structurally sound. Softeners that minimize water and salt use can also be efficiency rated. For a list of NSF International certified water softeners, visit: NSF/ANSI 44 certified softeners. Many consumers ask about non-salt systems and if they will reduce the hardness in the drinking water. These non-salt systems are designed to help control scale build-up in your Source: U.S. Geological Survey Office pipes, but not to soften water. Technologies that fall under this category include magnetic, electromagnetic, various Although hard water is not generally considered harmful for types of media, physical devices, chemical addition and more. people to drink, it can pose several problems for homeowners. Because they do not use cation exchange treatment For example, many soaps and detergents do not lather or clean technique, these products do not fall under the scope of as well in hard water, and surfaces exposed to hard water can NSF/ANSI 44. develop scale deposits that are difficult to clean. Excessive minerals in water can also form deposits that can For more information on water treatment systems, contact clog small diameter pipes over time, eventually restricting the NSF International’s consumer information specialist at flow of water. Hardness can also cause hair and skin to feel dry 734.418.6612 or [email protected]. because the minerals remain on the surface of our skin as the water evaporates. NSF International | T: +1.800.673.8010 | E: [email protected] | www.nsfconsumer.org .
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