Drinking Water Inspectorate

The use of chlorine dioxide in water systems results in its reduction to chlorite and chloride. In the UK the Drinking Water Inspectorate (DWI) restricts the use of chlorine dioxide in potable water supplies to a maximum of 0.5ppm total oxidants expressed as chlorine dioxide. This ensures that chlorite (and any chlorate) concentrations do not reach levels of potential harm to humans. 

DWI (Drinking Water Inspectorate) (1993), Further guidance on analytical systems (Department of the Environment London), Available http // www.dwi.gov.uk/regs/infolett/1993/info893.htm. 

Tests conducted for the Drinking Water Inspectorate show that some PVC pipes cause breaches of a new standard for lead due to be introduced in 2003. The failures are due to the use of lead salts to stabilise the plastic, and the DWI has warned pipe manufacturers that they must reformulate their products. 

UK,DRINKING WATER INSPECTORATE EUROPEAN COMMUNITY EUROPEAN UNION UK WESTERN EUROPE... 

List of Approved Products and Processes, Department for Environment, Food and Rural Affairs, Drinking Water Inspectorate, DWI, London, UK, 2003. 

The recent published reports on drinking water monitoring for pesticides in England and Wales published by the Drinking Water Inspectorate (DWI) showed that the drinking water standards was exceeded by 23 individual pesticides in 1996, 15 in 1997 and 12 in 1998. Among herbicides, the maximum detected levels was 0.21pg/l for attazine, 0.2 pg/1 for diuron, 0.13 pg/ 1 for isoproturon and 0.14 pg/1 for simazine in 1997-... 

Atkinson C, Blake S, Hall T, Kanda K, Rumsby P (2008) Survey of the prevalence of perfluorooctane sulphonate (PFOS), Perfluorooctanoic add (PFOA) and related compounds in drinking water and their sources DEFRA 7585 Drinking Water Inspectorate, Department for Environment, Food and Rural Affairs... 

The UK s trigger (Drinking Water Inspectorate, 2001) for optimising corrective water treatment to reduce plumbosolvency was 5% or more RDT samples exceeding 10 pg/1. It can be seen that this level of non-compliance was exceeded for most of the cases modelled. 

The phosphate dosed condition that was modelled (M = 0.02, E = 30) was predicted to achieve or only slightly exceed one of the UK s optimisation criteria (Drinking Water Inspectorate, 2001) for ortho-phosphate dosing, that no more than 2% of RDT samples should exceed 10 pg/1. This dosed condition has readily been achieved in practice and, where necessary, lower values of M and E have been achieved by shghtly higher phosphate doses in order to meet the 2% RDT target (Hayes et at, 2006, 2008). 

Drinking Water Inspectorate (2000). Determination of requirements to meet new lead standards. Information Letter 12/2000. 

The European Parliament and the Council have estabhshed a framework for Community action in the field of water policy, known as the Water Framework Directive. The Drinking Water Directive relates specifically to water intended for human consumption For example, in the United Kingdom the Water Quality Regulations prescribe maximum values for substances that affect wholesomeness and the Drinking Water Inspectorate polices the water companies. In the United States, the Environmental Protection Agency (EPA) sets standards for lap and pubhc water systems under the Safe Drinking Water Act (SDWA). 

With further new European standards for lead in mind (25 pg/1 from December 2003, 10 pg/1 from December 2013), the Drinking Water Inspectorate (DWI) issued Information Letters (DWI, 2000, 2001) that required the water companies in England and Wales to optimise treatment measures to reduce plumbosolvency, including the dosing of orthophosphate. Optimisation of plumbosolvency control treatment in England and Wales was required if >5% of at least 100 random daytime (RDT) samples had exceeded 10 pg/1 in the water supply zone(s) supplied by a treatment works and in consequence 95% of public water supplies are now dosed with orthophosphate for plumbosolvency control. 

Drinking Water Inspectorate (1992). Nitrate, Pesticides Lead 1989 and 1990. Department of the Environment, Welsh Office, London. 

Drinking Water Inspectorate (2010). Guidance document. Guidance on the implementation of the Water Supply (Water Quality) Regulations 2000 (as amended) in England. September 2010. 

Drinking Water Inspectorate (2011). Regional water quality reports for 2005 to 2009. Last consulted 1 October 2012. Available from www. dwi.gov.uk... 

Pressure Decay Test (PDJ)—Filled This test involves applying pressurized air to the feed side at a predetermined level below the bubble point and then isolating. When the pores of a membrane are flUed with liquid and air pressure is applied to one side of the membrane, surface tension prevents the liquid in the pores from being blown out by the air pressure below a certain minimum pressure known as the bubble point. The predetermined pressure directly relates to the size of defect under investigation [Drinking Water Inspectorate (DWI), 2001]. 

Drinking Water Inspectorate (DWI) (2001). Membrane integrity testing Membrane company level. In Review of the Adequacy of Existing Proposals for Membrane Integrity Monitoring. Available http //www.dwi.gov.uk/regs/pdf/mim.pdf, accessed May 22, 2006. 

Regulatory FDA 21CFR 176.170,176.180 BGACh. 36 UK Drinking Water Inspectorate approved... 

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