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Health Technical Memorandum 04-01: Safe Water in Healthcare Premises Part a on the NHS Website This document has been withdrawn. Find Health technical memorandum 04-01: safe water in healthcare premises part A on the NHS website. Department of Health Health Technical Memorandum 04-01: Safe water in healthcare premises Part A: Design, installation and commissioning withdrawn Health Technical Memorandum 04-01 Safe water in healthcare premises Part A: Design, installation and commissioning withdrawn Health Technical Memorandum 04-01: Safe water in healthcare premises: Part A – Design, installation and commissioning withdrawn © Crown copyright 2016 You may re-use this information (not including logos) free of charge in any format or medium under the terms of the Open Government Licence. To view this licence, visit www.nationalarchives.gov.uk/doc/open-government-licence/ or write to the Information Policy Team, The National Archives, Kew, London TW9 4DU, or email: [email protected]. This document is available from our website at https://www.gov.uk/government/collections/health-technical-memorandum-disinfection-and­ sterilization iiii Contents Contents Executive summary ...................................................................................................................iv Acknowledgements ..................................................................................................................vii Glossary and abbreviations ......................................................................................................ix 0 Policy and regulatory overview: water safety and the healthcare estate ......................... 1 1 Introduction To HTM 04-01 ................................................................................................. 7 2 Source of supply ................................................................................................................13 3 Materials of construction ...................................................................................................18 4 Water treatment and control programmes for hot and cold water systems .................. 23 5 Metal contamination ......................................................................................................... 27 6 Water softening ................................................................................................................. 28 7 Filtration ............................................................................................................................. 30 8 Water storage .................................................................................................................... 31 9 Cold water distribution system ......................................................................................... 40 10 Hot water services ............................................................................................................ 46 11 Building management systems ........................................................................................ 57 12 Pipework installations ....................................................................................................... 58 13 Noise and vibration ........................................................................................................... 62 14 Water economy and energy conservation ....................................................................... 63 15 Installation, testing and commissioning .......................................................................... 64 16 Documentation .................................................................................................................. 71 Appendix 1 Impact of water consumption on care pathways .............................................. 73 Appendix 2 Overviewwithdrawn of UK water legislation and regulation ...............................................74 References ............................................................................................................................... 76 iii Health Technical Memorandum 04-01: Safe water in healthcare premises: Part A – Design, installation and commissioning Executive summary Preamble to prevent stagnation in storage vessels and distribution systems. This current review and update of HTM 04-01 is intended to move users of the document This Health Technical Memorandum (HTM) towards a holistic management of water gives comprehensive advice and guidance to systems via Water Safety Groups (WSGs), healthcare management, design engineers, Water Safety Plans (WSPs) and other initiatives. estate managers, operations managers, contractors and the supply chain on the legal This version draws together and updates requirements, design applications, maintenance the previous guidance and includes and operation of hot and cold water supply, recommendations for the safe management storage and distribution systems in all types of of water systems, via the integration of the healthcare premises. It is equally applicable to principle of WSGs and WSPs (first introduced both new and existing sites. in the HTM 04-01 Pseudomonas aeruginosa addendum – published in March 2013), and how to manage and minimise the risks to health Aims of this guidance from various aspects, ranging from clinical risks, microbial and chemical contamination, The current review and update of HTM 04-01 changes to the water system, resilience of the is intended to move users of the document water supply etc. It also introduces a stronger towards a holistic management of water emphasis on staff competencies and the systems via WSGs, WSPs and other initiatives. implementation of water hygiene awareness It has been written to promote good practice training. for those responsible for the design, installation, commissioning, operation and maintenance of Introduction water services in healthcare premises, by: The development, construction,withdrawn installation, • highlighting the need for robust commissioning and maintenance of hot and governance and management; cold water supply systems are vital for public • outlining the remit of the WSG and how health. Healthcare premises are dependent this relates to the provision of safe water upon water to maintain hygiene and a in healthcare premises; comfortable environment for patients and staff, and for treatment and diagnostic purposes. • outlining key criteria and system arrangements to help stop the ingress Interruptions in water supply can disrupt of chemical and microbial contaminants healthcare activities. The design of systems and microbial colonisation and bacteria should ensure that sufficient reserve proliferation; water storage is available to minimise the • illustrating temperature regimes for consequence of disruption, while at the same sanitary outlets to maintain water time ensuring an adequate turnover of water hygiene; iv Executive summary • ensuring the safe delivery of hot water; colonisation of other waterborne organisms • outlining how the correct selection of within water systems. To prevent growth of P. system components and correct use by aeruginosa and other waterborne pathogens, occupants can help preserve the quality controls are necessary to manage the water and hygiene of water supplies; system before and after the outlet. • providing a point of reference to As with all control measures, temperatures legislation, standards and other guidance should be monitored at regular intervals to pertaining to water systems; verify effective control. • providing a basic overview of possible Because of the complexity of hot and cold potential waterborne pathogens; water distribution systems and the difficulty • giving an overview of some of the of maintaining a temperature control regime different water systems (including in some healthcare facilities, this guidance components) and their safe installation, suggests that additional chemical, physical commissioning and operation and and other water control methods that have maintenance; been shown to be capable of controlling • providing typical system layouts and microbial colonisation and growth may also be individual component location; considered. • providing information on thermostatic mixing valve configurations, appropriate Main changes from the 2006 usage and maintenance requirements; edition of HTM 04-01 • identifying key commissioning, testing • This 2016 edition of HTM 04-01 provides and maintenance requirements for comprehensive guidance on measures referral by designers, installers, operators to control waterborne pathogens and management; such as Pseudomonas aeruginosa, • identifying key commissioning, testing Stenotrophomonas maltophilia, and maintenance requirements Mycobacteria as well as Legionella. for referral by designers, installers, • This edition has been updated to align commissioners, operators and with the Health and Safety Executive’s management. (HSE’s) recently revised Approved Code of Practic e for Legionella (L8) Controlling waterborne pathogens and its associated HSG274 guidance documents. The guidance gives comprehensive guidance on measures to control withdrawnwaterborne pathogens. • The Addendum to HTM 04-01 published While Legionella control is, in the main, in 2013 (and now Part C of HTM 04-01) associated with poor engineering configuration introduced the concept of WSGs and and maintenance, with no evidence of patient­ WSPs. Part B of the HTM now includes to-patient or patient-to-outlet transfer, P. updated guidance on the remit and aims aeruginosa may be transferred to and from of the WSG and WSP. outlets and the water from both patients
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