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Test Water Before Getting Purifier


QUESTION: Our water seems fine, but I'm concerned about hidden contaminants that may harm my children's physical and mental health. Should I have the water tested? What water purifiers are best and cheapest to run?

ANSWER: The water should be tested in every home. Heavy metals, like lead, are known to be especially harmful to children and pregnant women. Lead can leach into your water from your plumbing. Low levels of other chemicals, like nitrates, are fairly harmless for adults but can be fatal to infants.

There are hundreds of other potentially harmful contaminants that may be in your water.

Simple tests for lead, performed by reputable labs, cost as little as $17. Most testing labs offer many standard water tests depending on your water source and any problems you are having with smell, taste, clarity, etc. Your local Environmental Protection Agency office can give you advice on selecting a testing service.

Once you learn from the water tests which water contaminants you need to remove, you can determine the most effective water purifier to install. You may choose point-of-use (one faucet) or more expensive whole-house models.

There are several basic water purifier technologies--carbon, distiller, reverse osmosis, ozone, deionization, ultraviolet light, etc. Many water purifiers on the market use various combinations of these technologies.

The costs to use these range from about 5 cents (large carbon filters) to 25 cents (distiller) per gallon of pure water. Base your selection on which type is most effective for removing the contaminants found in the tests.

The easiest units to install are counter-top models. I use a small counter-top distiller and an ozone purifier in my kitchen. Just plug them in and they are ready to use. There are also some small portable models for camping and a purifier water bottle for bikers and runners.

A distiller produces very pure water, and the boiling process kills bacteria and virus; however, it produces pure water slowly. Ultraviolet light and ozone purifiers also kill these microbes.

Reverse osmosis purifiers are very effective, but some models may use extra water for processing. Deionization purifiers electrically charge the contaminates in the water so they stick to a special replaceable cartridge.

Carbon filters improve water's taste and smell. They also remove many carcinogenic organic chemicals. A block type removes more particles than a granular type. Most distillers and reverse osmosis purifiers include small carbon elements.

Write for Update Bulletin No. 423, a buyer's guide of 22 water purifiers and water testing labs, types, features, prices and water problem and purifier selector charts. Please include $2 and a business-size self-addressed, stamped envelope and mail to James Dulley, Los Angeles Times, 6906 Royalgreen Drive, Cincinnati, OH 45244.

Lighting for Computer Should Be Indirect

Q: I am setting up a computer room in my house. Do you have any tips for the best and most efficient type of lighting to use?

A: A computer room requires indirect lighting to avoid glare and reflections from the monitor screen. Use fluorescent lights where possible for efficiency and direct the lights toward the ceiling.

Use an asymmetrical task light (oblong light pattern) over the keyboard and work area. Adjust the monitor brightness to the same intensity as the rest of the light in the room. This minimizes how often your pupils close and open and reduces long-term eyestrain.

New Batt Insulation Works, Doesn't Itch

Q: I want to add some batt insulation to my attic. I am considering using the batts that are wrapped in plastic film so I don't itch as much. Will the plastic wrap trap moisture in the insulation?

A: The plastic wrap has thousands of tiny perforations. These allow moisture to pass through and escape without reducing the effectiveness of the insulation. Since the wrap blocks some air circulation through the insulation, it actually insulates more effectively. If you are concerned about itching, Owens Corning makes a new "no-itch" batt insulation called Miraflex.

Letters and questions to Dulley, a Cincinnati-based engineering consultant, may be sent to James Dulley, Los Angeles Times, 6906 Royalgreen Drive, Cincinnati, OH 45244. To read 150 previous columns or rush bulletin delivery, e-mail Dulley at

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