Association between swimming pool operator certification and reduced pool chemistry violations--Nebraska, 2005-2006

Bryan F Buss1, Thomas J Safranek, Julie M Magri

  • 1Nebraska Department of Health and Human Services, Division of Public Health, Lincoln, NE 68509, USA. bryan.buss@nebraska.gov

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Quality of Water01:19

Quality of Water

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Testing Water Quality

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Deleterious Substances in Aggregate01:25

Deleterious Substances in Aggregate

Deleterious substances in aggregates can be detrimental to the quality and durability of concrete. These substances include organic impurities like loam, which interfere with cement hydration and are usually present in the sand. These prevent a good bond between aggregate and cement paste. Organic impurities can be detected using the colorimetric test, where the darkness of a solution after agitation indicates the level of organic content.
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Microbial Bioremediation of Pesticides

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Plasticizers01:31

Plasticizers

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