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Copper-silver ionization is a disinfection process, primarily used to control ''Legionella'', the bacteria responsible for Legionnaires' disease (legionellosis). It is possible to operate copper-silver ionization in the United States (US) without exceeding the copper Action Level (AL) and silver secondary maximum contaminant levels (SMCLs) set by the U.S. Environmental Protection Agency in the Safe Water Drinking Act's Lead and Copper Rule (Title 40, Code of Federal Regulations, 40 CFR) in Part 141, Subpart I; and 40 CFR Part 143, respectively. ==Process== Copper-silver ionization disperses positively charged copper and silver ions into the water system. The ions bond electrostatically with negative sites on bacterial cell walls and denature proteins.〔 Over the long term, the presence of copper and silver ions destroy biofilms and slimes that can harbor ''Legionella'', the bacteria responsible for Legionnaires' disease (legionellosis). It can take 30 to 45 days for the copper and silver ions to penetrate a biofilm. Flow cells (part of the ionization unit) should be cleaned periodically to maintain the system. In a hospital that is not defined as a public water system, this task may be delegated to the facility's utility engineers. If a hospital is defined as a public water system, the maintenance personnel may be required to have a State-issued water treatment license. In the US, different states have specific regulations for hospitals and drinking water treatment that should be reviewed before going forward with installation of copper-silver ionization. Forensic scientist Randy Fornshell of the Sedgwick County Regional Forensic Science Center explains that copper-silver ionization is a modern implementation of the ancient Greek practice of reducing bacteria in wine vessels by lining them with silver, and controlling algae and fungi with copper. Fornshell notes that copper-silver ionization has been effective in swimming pools (it is an alternative to chlorine) and is becoming adopted by larger municipalities. Replacing chlorination with copper-silver ionization to keep water safe was one response of Frederick Memorial Hospital, Frederick, Maryland, to new requirements in the 2001 ''Guidelines for Design and Construction of Hospital and Healthcare Facilities'', issued by the American Institute of Architects. Ionization is in many cases installed because more convenient and cost-effective than other approaches.〔 This implies that Maryland does not identify systems that post-treat potable water as public water systems and require them to maintain a residual of chlorine or chloramine in their distribution system, as required for treated surface water in the Safe Drinking Water Act. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Copper-silver ionization」の詳細全文を読む スポンサード リンク
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