Southwest States & Pacific Islands Regional Water Program Tagline Glass of water

Aloha and Welcome to the Water Data Interpreter

This program will help you interpret the results of a routine domestic water analysis, performed by a certified drinking water analysis laboratory. The routine domestic water analysis tests for characteristics that could affect health and uses of water. Use your report to find the levels that correspond with the contaminants listed.

The results in the report you get back from the lab will show numbers in different units. In the drop down menu beside each contaminant, choose the unit appropriate for your number. Note: 1 ug/L or microgram per liter represents 1 part per billion (ppb). 1 mg/L or milligram per liter is equivalent to parts per million (ppm). 1 ug/ml or microgram per milliliter is equivalent to parts per million (ppm).

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Certified Drinking Water Analysis Laboratories by State

Arizona Department of Health Services. Visit the Environmental Laboratory Licensure Program website link, and click on the Safe Drinking Water Commercial Laboratory list for commercial laboratories licensed by the Office of Laboratory Services to perform drinking water testing in Arizona.

Visit the Hawaii Department of Health (DOH), Safe Drinking Water Branch and look for Drinking Water Testing Labs (378 KB pdf), which is a listing of labs certified or approved by the DOH State Laboratories Division.

Visit the California Department of Public Health website's page on the Environmental Laboratory Accreditation Program (ELAP) and look for Certified Laboratory List (Excel). The information provided in the list is subject to change and may not be current. The list is periodically updated to reflect the changes based on information available in ELAP at that time.

The Guam Environmental Protection Agency, Drinking Water Laboratory
(671) 472-8863
Monitoring Services Division
Guam Environmental Protection Agency
15-6101 Mariner Avenue, Tiyan,
Barrigada, Guam 96913
(or mailing address: PO Box 22439 GMF, Barrigada, Guam 96921)

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Our Terminology and Definition List

Aluminum: the most abundant metal in the earth’s crust. Occurs only in combination with other elements such as oxygen, silicon, and fluorine. Read More >>

Arsenic: an inorganic crystalline element that is brittle, metallic steel-gray and poisonous; occurs naturally in the environment. Read More >>

Barium: an inorganic metallic element that is malleable, silver-white, toxic and occurs only in combination with other chemicals. Read More >>

Cadmium: (total) is a naturally occurring metal that is found in rocks and soil, typically in association with zinc ores. Read More >>

Calcium: (calcium hypochlorite) is a white solid that readily decomposes in water releasing oxygen and chlorine. It also has a strong chlorine odor. The compound occurs naturally in the environment.

Chloride: naturally occurring salts.

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