WATER HYGIENE AND SAFETY


Biofil spout filters ‘guarantee water quality and maintain activity space’.


contaminated water will drip onto the sink surface while reaching for a paper towel. Any dispenser (soap or paper towel) located above the sink will increase the risk of cross-contamination of fittings and pipework. However, electric hand-dryers which collect water in the base are not recommended either, as contaminated water can blow back onto patients. In the absence of a design solution, user behaviour is paramount, i.e. hands must be washed thoroughly to prevent transmission.


The Tempomatic WC electronic direct flush valve eliminates stagnant water.


and Health Technical Memorandum HTM 04-01 Part B5


recommends removing


showers (and their associated pipework) in existing buildings, and assessing the need for them in new premises to prevent stagnation due to low usage and deadlegs. For basins, sinks, and showers, the waste


also presents a high risk of P. aeruginosa contamination. Given the right conditions (oxygen and optimal temperatures), bacteria will develop and spread from the P-trap into the waste tail piece. In their 2019 study, Kotay et al6


wastes to patients. According to Kotay et al, the ideal solution is to prevent bacteria from establishing a foothold: “…for dispersion to occur, the presence


of bacteria on the drain and/or bowl surface is necessary… as long as the sink drain and bowl remain free of the target organisms [], dispersion can be controlled.”6


suggest that water


flowing directly onto a basin or sink waste will cause bacteria to disperse. In some instances, P. aeruginosa was detected up to 15 cms above and away from the waste during use. Therefore, solutions need to be designed and engineered to eliminate or minimise the risk of transmission from


Importance of spatial planning Spatial planning is also vital. Maintaining a 1 m splash zone relative to patient beds will avoid droplet dispersion. Contamination can also be minimised by correct location of soap and paper towel dispensers. Drips are the main culprit. Soap that has dripped onto the sink surface is a potential source of nutrients for bacteria, and if impeccable hand hygiene is not fully maintained,


Managing the flush BS 8580-2:2022 also identifies toilets as a source of environmental contamination, via direct contact and/or aerosol spread. A study by Li, Wang, and Chen in 20207 into virus transmission found that flushing the toilet expels microbe-contaminated bioaerosols. They concluded that transmission of contaminated matter can be reduced by closing the toilet lid before flushing; cleaning the toilet seat to eliminate any floating particles that may have settled on the surface, and washing hands carefully after touching the flush button and door handle. The BSI code of practice2


recommends assessing whether


a toilet lid is required. This decision may be determined by the proximity of the toilet to the splash zone, and balancing the risk of droplet contamination from the flush plume against the risk of contamination via splashing from the sink. So, can the transmission risk associated


with toilets be eliminated or minimised? A French hospital found that the epidemiological source of a recent Legionella contamination episode was the toilet cistern. Cisterns increase the contamination risk because water is stored at ambient temperatures in the presence of oxygen; ideal conditions for bacterial development. It is possible to eliminate cisterns, replacing them with a direct flush system which connects directly to the water supply. A self-closing valve discharges a predetermined flush volume without the need for stored water. Hygiene can be further improved by installing an electronic flush mechanism. For example, Delabie’s Tempomatic WC, with an automatic sensor, detects the user and flushes the valve automatically – ideal if the user has reduced mobility.


Stainless steel has a smooth, non-porous surface ‘ideal’ for areas that demand high standards of hygiene.


48 Health Estate Journal October 2022


Material specification matters Where it is not possible to eliminate the contamination risk, it must be reduced to a minimum to prevent bacterial proliferation (amplification). This entails managing the system conditions that support bacterial growth, such as temperature, water flow, and ‘turn over’, as well as the presence of nutrients (e.g., scale, biofilm, and corrosion). The choice of material for fixtures and fittings within the water distribution


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92  |  Page 93  |  Page 94  |  Page 95  |  Page 96  |  Page 97  |  Page 98  |  Page 99  |  Page 100  |  Page 101  |  Page 102  |  Page 103  |  Page 104  |  Page 105  |  Page 106  |  Page 107  |  Page 108  |  Page 109  |  Page 110  |  Page 111  |  Page 112  |  Page 113  |  Page 114  |  Page 115  |  Page 116  |  Page 117  |  Page 118  |  Page 119  |  Page 120  |  Page 121  |  Page 122  |  Page 123  |  Page 124