This Published Document provides guidance on cleaning, flushing and disinfection of services supplying water for domestic purposes within buildings and their curtilages, including those for the production of foods, but excluding closed systems or other industrial processes. NOTE1 See the Water Quality Regulations [7], [8], [9] and [10] and BSRIA Guide29-2012 [18] for cleaning closed systems. “ Domestic purposes?? refers to water used for drinking, washing, cooking and sanitation. The guidance is intended to help prepare new and existing systems for use and control microbiological growth in water systems for supply, storage and distribution, to ensure that: residues of construction are adequately flushed from water distribution systems; appropriate water quality is achieved; appropriate disinfectants and processes are used; construction debris and dust are removed; risk of corrosion and damage to fixtures, fittings and sensitive plant is minimized; adequate records of cleaning are produced; stagnation is avoided or managed; and appropriate tools and personnel are deployed for the relevant tasks. The guidance applies to: initial commissioning of new or extended systems; maintenance of existing systems; alteration of existing systems; water quality management prior to occupation or as a result of low/no occupancy or usage; and (remedial) response to microbiological problems is identified. NOTE2 The techniques set out in this standard are also applicable to the management of premises and systems where water is provided from a private supply.