Decontamination in primary care dental practices - Gov.uk

17 Steam and water quality17 Steam and water quality17.1 For the purposes of this document, either one ofthe following types of water is considered suitable:sterile water for irrigation; distilled water; reverseosmosis water or suitable potable water (seeparagraph 3.14).Steam17.2 Decontamination within a dental decontaminationfacility should ensure that the quality and safety ofthe instruments are not affected by thedecontamination process itself.17.3 Factors affecting the quality of the steam, and thusthe safety of the instruments, include the following:material of chamber construction; quality of feedwater;conditions of storage of feed-water; periodbetween changes of feed-water.Quality of input water17.4 The quality of input water for benchtop sterilizers isdefined in Annex C of BS EN 13060. Care shouldbe taken to observe use-by dates. Any water unusedor left in opened containers at the end of the dayshould be discarded.Conditions of storage and frequency of change17.5 Feed-water may be stored in a reservoir in themachine and can be either reused or used once only.While both are acceptable, there is some advantagein using the water once only in that there is nobuild-up of contamination within the reservoir.17.6 However, even high-quality water is subjectto microbial contamination. For this reason –irrespective of whether the water is used onceonly – the reservoir should be emptied at such afrequency as to eliminate microbiological build-up.17.7 Current recommendations are for the reservoir tobe drained down and cleaned at the end of eachworking day or daily shift. Water should not be leftin the machine overnight.WaterThe configuration of water supply networks nowmeans the water sources from which supplies aredrawn may vary considerably in many parts ofEngland, such that hard water can appear in normallysoft water areas. The local water supplier (undertaker)will be able to advise on local supply quality andpotential changes.Cleaning17.8 Cleaning and rinsing (either manual or automated)can be performed with potable water as long as thewater hardness is low enough and other aspectsof water quality are satisfactory. This should beconfirmed with the manufacturer of the washerdisinfectorand detergent.17.9 Practices should check with the detergentmanufacturer that level of hardness is compatiblewith the detergent used and for its use in a washerdisinfector.If the input water has a hardness that isnot compatible, water softening is expresslyadvised. An ongoing knowledge of the hardness ofthe incoming water feed is therefore necessaryFinal rinsing17.10 The final rinsing of instruments – for example,those washed manually, in an ultrasonic bath or ina washer-disinfector – should be carried out usingsatisfactory potable water, or RO water or distilledwater.Detergents17.11 The efficacy of cleaning will depend on therelationship between potable water quality anddetergent performance. The detergent should bechosen for its cleaning efficacy and itscompatibility with the water quality.65