Prevention of infections through water and water-using equipment

Transcription

1 Hospitals Prevention of infections through water and water-using equipment This document may be reproduced and distributed freely, provided that the Dutch Workingparty Infection Prevention is cited as the author each time. Please make sure that you have the most recent version of this document. To do so, go to Once a new version of a guideline appears on the website, the Dutch Workingparty Infection Prevention is no longer responsible for the content of the versions it replaces. Dutch Working Party Infection Prevention Published: May 2002 Changed: December 2003 Revision: May 2007

2 Table of contents Introduction Water systems in general Construction and expansion of the system Clear-water reservoir Own water well Cold water system Drinking water Softened water, demineralised water, reverse osmosis Decorative fountain water Fire hoses Warm water system Installation and expansion of the system Hot water system Periodic microbiological tap water inspection Carrying out the inspection Personal protection when rinsing through Steam system Water in various applications Humidification in ventilation systems Nebulising equipment Therapy baths Infusion warmers Disinfection of scopes Showers Emergency showers and eye washes Rinsing water (medical equipment) Dialysis water Urology rinsing water Ice machines Melt water from refrigerators Flower water Appendix A References Prevention of infections through water and water-using equipment

3 Introduction Dutch drinking water is very high in quality and the water companies do everything possible to be able to continuously guarantee this quality, particularly with regard to biological reliability. In a European context, legal requirements have been formulated which have been in effect in the Netherlands since the year 2000, brought together in the Water Supply Act [1]. The point of departure is that everyone everywhere must have good and safe drinking water at their disposal. In this condition, water is supplied to all customers, including health care institutions, through the water supply system. Nevertheless, much can go wrong from both a microbiological and a toxicological point of view before the water is ultimately consumed or used for other purposes. This guideline only addresses the microbiological aspects. As far as the toxicological aspects are concerned, requirements with regard to used materials, installation and maintenance are described in the regulations of KIWA- ATA (KIWA Assessment on Toxicological Aspects), NNI (Netherlands Standardisation Institute), VEWIN (Association of Water Company Operators in the Netherlands) and ISSO 55.1 (Building Services Research Institute publication 55.1) [2-4]. Whereas the water company monitors and guarantees the quality of the water up to the water meter, within the home water systems and particularly when this concerns large (hospital) systems, in a number of places there is a real danger of contamination and growth of microorganisms in the supply system, such as Pseudomonas aeruginosa, Burkholderia cepacia, Serratia marcescens, Acinetobacter calcoaceticus, Flavobacterium meningosepticum, Aeromonas hydrophila and Legionella pneumophila, mycobacteria, Pseudomonas, Sphingomonas, Aeromonas, pathogenic amoebas such as Naegleria fowleri and Acanthamoeba and fungi [5]. The most frequently occurring of these is contamination with Legionella pneumophila [6, 7], which can cause sudden, severe pneumonia in patients [8]. The infection of a large number of people in Bovenkarspel, the Netherlands with Legionella in 1999 was reason for the Dutch government to impose governmental preventive measures. For this reason the subject of Legionella is not addressed separately in this guideline. Provided that they are complied with properly, the government measures may be expected to prevent problems of the other above-mentioned microorganisms in addition to Legionella [9]. There is an additional danger of growth of microorganisms when using inferior installation materials, in a mixing water system, an incorrect installation method, insufficient technical maintenance, connection to the installation of other (emergency) water supply facilities (own water well, drinking water reservoir, clear-water reservoir) and water processing devices (softeners, warmers, heaters, etc.) which do not meet the requirements and/or failing to carry out periodic inspection and/or maintenance. Therefore, quality promotion and control within the institution is extremely important. Prevention of infections through water and water-using equipment 3

4 1 Water systems in general 1.1 Construction and expansion of the system The most optimum possible water flow rate through the pipes is very important. This is promoted by: - using a water supply pipe with the smallest possible diameter, of course provided that it is large enough for the capacity required on the spot. - installing several pipes in parallel if the capacity requires this. - installing the pipes without diversions (good flow through everyday). - preventing dead ends. Draw-off points that are no longer used must be closed off up to the water main. If a draw-off point that was closed off is brought into use again, the pipe must be flushed through before putting the draw-off point into use. KIWA-ATA approved installation materials are used to prevent the pipes from containing excessive biofilm and/or harmful concentrations of substances originating from solder, packaging, etc. The materials used may not be growth-stimulating. The water supply system must be clearly recognisable as warm-water or cold-water pipes (through colour or marking), to minimise the chance of making incorrect connections. Warm-water and cold-water pipes must be installed in such a way that the cold water is not heated up. A detailed description/drawing of the whole water system must be available in a documentation system. Notes/adjustments must be made to this in the event of any change to the system. If a circulating system is involved, there must always be facilities for measuring the water temperature at the return site, for monitoring purposes. Technical provisions are installed to prevent water from a home system from flowing back to the public mains system. For relatively small systems, such as those for nursing homes and rest homes, non-return valves are installed in the supply line. Hospitals require a continuous water supply. Therefore a clearwater reservoir is used for the water supply to hospitals. Non-return valves are operated in accordance with the water company s procedure. 1.2 Clear-water reservoir If a clear-water reservoir is present, samples of the water in the clearwater reservoir must be taken every three months for microbiological examination. 4 Prevention of infections through water and water-using equipment

5 Particularly in the summer, a clear-water reservoir can cause many problems in the hospital. If the result of the examination gives reason to do so, the clear-water reservoir is drained, cleaned and disinfected. For the cleaning and disinfection procedure as well as the required (quantity of) disinfectant, see the appropriate VEWIN worksheet [10]. 1.3 Own water well If the institution has its own water well for drinking water, the quality of the water must be inspected to make sure it meets the standards of the Water Supply Act [11]. 2 Cold water system 2.1 Drinking water Before a (partially) new system is brought into use and following repairs, it must be cleaned and, depending on the diameter and the length of the pipe, also disinfected. Rinsing through with drinking water is sufficient for pipes with an internal diameter up to 100 mm and also for pipes with a diameter up to 150 mm and a length up to 10 metres. The pipe must be flushed through for long enough that at least 20 times the normal volume of the pipe has run through. Pipes with an internal diameter of 100 mm or more and short pipes (up to 10 metres) with an internal diameter of 150 mm or more must be cleaned and then disinfected with a chlorine solution. For the correct method of cleaning and disinfection and the chlorine concentration, see the appropriate VEWIN worksheet and ISSO 55-1 [4, 10]. 2.2 Softened water, demineralised water, reverse osmosis Softened water, demineralised water and reverse osmosis water are not suitable for internal or external contact with the human body, nor for spraying. Because of the presence of materials (such as resins) used to prepare softened and demineralised water, after-growth of microorganisms can take place. 2.3 Decorative fountain water Fresh running water is to be used in decorative fountains. Recirculating water in decorative fountains, particularly if these fountains are placed indoors in a heated environment, can form a source of infection because they can contain large quantities of microorganisms. Prevention of infections through water and water-using equipment 5

6 The temperature of the water in the fountains must be checked regularly. This temperature applies to the whole system; hot spots must be avoided. 2.4 Fire hoses In the event of stagnant water in a fire hose, the temperature may be favourable for Legionella growth. However, when the hose is used to put out a fire, the contents of the hose will be discharged within seconds, after which the hose will be filled with fresh water. Therefore the time of exposure will be minimal. The fire hose must be flushed through twice a year. The water from the fire hose may not be used for any purpose other than putting out a fire. Other use of the hose can be prevented by sealing the hose and checking the seal every month. 3 Warm water system In view of the seriousness of the infections it can cause, Legionella is the most notorious microorganism that can be present in tap water. Besides Legionella, other after-growth pathogens such as mycobacteria, Pseudomonas, Sphingomonas, Aeromonas and pathogenic amoeba such as Naegleria fowleri and Acanthamoeba can multiply in the pipes if the temperature of the tap water drops below the critical limit of 60 C. To prevent this problem, flow and water temperature control are essential issues when designing the system. For more information, see the Dutch government s Legionella control plan and the ISSO publication Legionella Prevention Manual [4, 11]. Warm water must be mixed at the draw-off point from warm and cold water. A system in which mixed water of C is prepared centrally from warm and cold water, can never meet the 60 C requirement and will never meet the requirements of the Legionella control plan. 3.1 Installation and expansion of the system The water in the whole warm water system must be carefully maintained at a temperature of at least 60 C. This implies that the distance of the pipe may not be too long, to rule out the chance of the water cooling to less than 60 C. In order to achieve this, a return pipe must be installed and the water temperature at the end of the return pipe must be measured and registered continuously. Mixing taps must be capable of immediately closing off completely by means of a non-return valve if the cold water pressure is lost. 6 Prevention of infections through water and water-using equipment

7 This mechanism, which is not available in some brands of mixing taps, serves to prevent water from the warm water system from winding up in the cold (drinking) water system. This mechanism prevents burns. 4 Hot water system The water in hot water systems has a temperature of at least 80 C. These systems are subject to specific technical requirements. From an infection point of view, a hot water system must at least meet the same requirements as a warm water system. 5 Periodic microbiological tap water inspection A tap that does not leak is chosen, so that no water from the tap body gets into the sample. The water is collected in a wide-mouth receptacle (wide-mouth vessel to collect liquid) without the tap touching the inside. The cover is placed down in such a way that no water can splash into it, so not upside down, and not placed in the bag. The culture must be started within 24 hours. The sample is stored at 4 to 10 C, also during transport. If melting ice is used, the melt water of the melting ice may not come in contact with the sample. 5.1 Carrying out the inspection The periodic inspection should mainly be focused on the presence and after-growth of Legionella and/or E.coli. It is always carried out following manipulations to the system, at the points that form a risk according to the Legionella control plan, such as: - the most remote parts of the pipes. - for cold water systems: where the water is the warmest. The selections of sample points and inspection frequency depend on the nature of the system. Periodic inspection with a time interval of three months is acceptable. If it turns out following continuous microbiological examination that the requirements have been met, checking the temperature is sufficient in accordance with the Legionella control plan. For the frequency and the duration of discharging the necessary dead ends (such as draw-off points that are not used often), refer to the Dutch government s compulsory Legionella control plan [11]. The initial inspection of warm water is a temperature check. If the temperature is less than 60 C, a bacterial inspection is useful. Prevention of infections through water and water-using equipment 7

8 The draw-off point selected for inspection must be the one furthest removed from the source. To find out which microorganisms are present in the last piece of the pipe before the draw-off point, the water sample is taken as soon as the draw-off point is opened. To find out which microorganisms are generally present in the system of pipes, a volume of water equal to the pipe volume between the draw-off point and the water to be sampled must be allowed to discharge before the sample can be taken. The presence of E.coli and enterococci is a warning. The culture must be repeated. If the coliforms are present in the repeated culture, measures must be taken. This is outside the scope of this guideline; the technical department and the water company must be consulted. Acute measures, such as closing off the water supply are only required in the event of serious faecal contamination. According to the standards established by the government, no more than 50 CFU Legionella per litre of water may be found. If this amount is exceeded, measures must be taken. 5.2 Personal protection when rinsing through When rinsing through the pipes with the necessary dead ends (such as emergency showers and other seldom used draw-off points) each month, a funnel with a hose must be used directly under the shower or the drawoff point, to prevent the formation of spray as much as possible [4]. 6 Steam system There are no hygienic aspects for a steam system. As far as the technical aspects are concerned, refer to the Sterilisation and Sterility guidelines [12]. 7 Water in various applications 7.1 Humidification in ventilation systems Steam is used for humidification in climate control systems. The steam humidifier must be placed in a double-walled cabinet, with a water separator in the steam supply and a condensation drain. This moisture must be prevented from accumulating in the climate control system must be prevented. Leak water/condensation and the like must be drained off immediately. Air filters must remain dry. 8 Prevention of infections through water and water-using equipment

9 7.2 Nebulising equipment See the WIP guideline Inhalation therapy [13]. 7.3 Therapy baths See the WIP guideline Infection prevention in physiotherapy [14]. 7.4 Infusion warmers Infusion liquids can be heated in several ways: dry or in a liquid. In some systems only the infusion bag can be heated, and in others the infusion liquid is heated through the infusion system. The use of infusion warmers that use heating liquids, in which the heating liquid can come into contact with the infusion bag, are not recommended. If liquid reservoirs are nevertheless used to heat up infusion liquid or blood, these must be emptied and stored dry after each use. They are filled with sterile water immediately before use. Before the reservoir is filled again, it must be disinfected with 70% alcohol. Keep track of the frequency in a chart. Take the above-mentioned recommendations into account when purchasing infusion warmers. If the heating water does not come into direct contact with the infusion system, it is refreshed according to the replacement frequency indicated by the supplier. 7.5 Disinfection of scopes See WIP guideline Scopes [15]. 7.6 Showers Shower heads must be maintained in accordance with the Legionella control plan. Showers that have not been used for more than 5 days, must be flushed through as standard procedure. It is recommended that seldom used showers be fitted with a drain down valve. 7.7 Emergency showers and eye washes Emergency showers are very seldom used and are often placed on terminal pipes. Prevention of infections through water and water-using equipment 9

10 These pipes must be kept as short as possible. The emergency showers must be flushed through once a month, to prevent (microbiological) contamination. If there is a chance of spray formation, this is done holding a funnel with a drain hose directly under the draw-off point. Eye washes that are directly connected to a frequently used cold water tap are preferred. 7.8 Rinsing water (medical equipment) Equipment that provides water at body temperature for rinsing constitutes a microbiological risk because of this temperature of 37 C. The water in these devices and pipes must be heated to a temperature of 80 C at the end of each day of use, according to a permanently set program. Sterile water from bags or bottles is used for rinsing sterile body cavities. 7.9 Dialysis water See WIP guideline Infection prevention in haemodyalisis [16] Urology rinsing water See WIP guideline Infection prevention in urology [17] Ice machines Ice machines are used to prepare ice for consumption, for cooling medicaments and for cooling the skin. The bacteriological quality of the ice can never be better than that of the water used. The ice machine can contain many types of microorganisms, such as Pseudomonas, E.cloacae, Legionella pneumophila, M.gordonae, M.fortuitum, Acinetobacter, Aeromonas, Flavomonas, S.epidermidis and yeasts [18, 19]. For cool storage of medicaments during administration, the melt water may not come into contact with the covering of the medicament. The ice must be used in bags. Open ice storage bins may not be placed under a fan for air cooling. A closed system must also be used here. The ice machine must be connected to the water supply system. Manually filling the ice machine with water is not recommended. The ice is removed from the machine with a scoop, whereby the hands must be prevented from contacting the ice. Ice cubes removed from the ice machine may not be put back in it. 10 Prevention of infections through water and water-using equipment

11 The scoop must be kept dry and free of dust in a container outside of the machine. The scoop must be cleaned and then disinfected with 250 ppm chlorine everyday, or washed in the department s dishwashing machine. The ice reservoir must be closed. To prevent water from returning through the drain, melt water must be discharged to the drain through a break. Every week, the ice machine must be cleaned, then disinfected with 250 ppm chlorine, rinsed thoroughly and dried. Once it is dry the machine may be switched on again. The machine must be serviced technically at least once a quarter. A logbook of these activities must be present Melt water from refrigerators Besides cleaning the refrigerator, check the interior for icing up and defrost the refrigerator if icing up is present. Because the melt water can contain many microorganisms, attention must also be paid to the drain tube for the melt water. To prevent blockage, it must be cleaned with a small brush Flower water Flowers in a patient s room generally last no more than 1 week. If a preservative (such as Chrysal clear ) provided with the flowers is added to the flower water to prevent growth of microorganisms, the flower water should only have to be changed once a week. Thus, in practice, changing the flower water is seldom necessary and filling up the flower vases with the preservative provided with the flowers diluted in fresh tap water is sufficient. Should it nevertheless be necessary to change the flower water, this must take place in the utility room. The flower water is carefully poured off and the vase is cleaned before it is reused. The vase can be cleaned in a bedpan rinser or a dishwashing machine [20]. After changing the flower water the hands are washed or rubbed with hand alcohol. Prevention of infections through water and water-using equipment 11

12 Appendix A References 1. EG, Richtlijn Raad betreffende kwaliteit van voor menselijke consumptie bestemd water NNI-normcie, Algemene voorschriften voor drinkwaterinstallaties Norm NEN VEWIN and V. Vereniging van exploitanten van waterleidingbedrijven in Nederland, Werkblad drinkwaterinstallaties WBO. Rijswijk, ISSO, Handleiding Legionella-preventie in leidingwater Publicatie Warris, A., P. Gausted, and e. al, Recovery of filamentous fungi from water in a pediatric bone marrow transplantation unit. J Hosp Infection, : p Slater, F.M., Water management. Saunders infection control reference service, Philadelphia: p Hunter, P.R. and S.H. Burge, Monitoring the bacteriological quality of potable waters in hospital. J Hosp Inf, : p Hoebe, C.J.P., J.J.M. Cluitmans, and J.H.T. Wagenvoort, Two fatal Cases of Nosocomial Legionella pneumophila Assiciated with a Contaminated Cold Water Supply. Eur J Clin Microbiol Infect Dis, (art. 151)(Springer-Verlag). 9. VROM and r.o.e.m. Ministerie van Volkshuisvesting, Voorontwerp Tijdelijke regeling Legionella-preventie in leidingwater. Staatscourant, : p. december. 10. VEWIN, Werkblad doorspoelen (spuien) en desinfecteren van drinkwaterinstallaties. WB, ,4(Rijswijk). 11. VROM and r.o.e.m. Ministerie van Volkshuisvesting, Waterleidingbesluit NNI-normcie, Steriliseren en steriliteit. Richtlijnen Steriliseren en steriliteit, R/D8000 Apparatuur. 13. W.I.P., Inhalatietherapie. Richtlijn, A. 14. W.I.P., Infectiepreventie in de fysiotherapie. Richtlijn, a. 15. W.I.P., Reiniging en desinfectie van scopen. Richtlijn nr. 21b, 2001: p. in bewerking. 12 Prevention of infections through water and water-using equipment

13 16. W.I.P., Infectiepreventie bij hemodialyse. Richtlijn, Nr W.I.P., Infectiepreventie in de urologie. Richtlijn, Wilson, I.G., G.M. Hogg, and J.G. Barr, Microbiological quality of ice in hospital and community. J Hosp Infect, : p Burnett, I.A., G.R. Weeks, and D.M. Harris, A hospital study of ice making machines: their bacteriology, design, usage and upkeep. J Hosp Infect, (4): p Daha, T., Bloemen. Tijdschr Hyg Inf Prev., : p Prevention of infections through water and water-using equipment 13