footprint, but with the correct measures in place it can be taken a step further. Scalding When discussing temperature control of DHW, the risk of scalding must always be considered, especially in the health and social care sector. This is an area that often provides care for individuals who may be more vulnerable to risks from hot water such as children, elderly people, those with less physical or mental ability or a sensory issue. According to the Health and Safety &YFDVUJWF )4& UFNQFSBUVSFTPWFS$ can create a scalding risk and as such water temperatures discharged from outlets accessible to those vulnerable or where there is the potential for full body immersion must not exceed this UFNQFSBUVSF&OHJOFFSJOHDPOUSPMTTIPVME be put in place in order to ensure this. These include thermostatic mixing valves (TMVs) which should be placed as close to the outlet as possible. Legionella & ACOP L8 National guidance underpins safety at work, and specic guidance for the DPOUSPMPG-QOFVNPQIJMBJOXBUFS systems is provided in the Health and 4BGFUZ&YFDVUJWF QQSPWFE$PEFPG 1SBDUJDF $01- BOEJUTBTTPDJBUFE SFHVMBUJPOT )4(1BSU $01 -HPWFSOTUIFDPOUSPMPG-FHJPOFMMBJO XBUFSTZTUFNT-FHJPOFMMBoGVMMOBNF -FHJPOFMMBQOFVNPQIJMBoJTBCBDUFSJB that causes, amongst other less serious DPOEJUJPOT -FHJPOOBJSFTEJTFBTF B potentially fatal form of pneumonia. -FHJPOFMMBCBDUFSJBBSFDPNNPOJO natural water sources but the conditions are rarely conducive to people catching the disease. This usually occurs in Table 1 Continuous ow Storage w/h .BY)FBU*OQVU L8 Max heat output (kW) &GmDJFODZ (SPTT 56 65 TUIPVSnPXSBUF! $SJTF MIS 4UPSBHF$ZMJOEFS - $POUJOVPVTnPXSBUF MIS Peak usage periods (hr) Number of peak usage QFSJPET )FBUJOHDPOTVNQUJPO L8 Storage recovery time (mins) 4UPSBHFSFDPWFSZ L8 4UPSBHFMPTT L8I Secondary return system heat loss per hour (kW) &GmDJFODZ FGmDJFODZ DVSWFPGBQQMJBODF Appliance input for s FDPOEBSZTZTUFN L8 Secondary system operating time (hr) 3FIFBUPGTFDPOEBSZ SFUVSO L8IEBZ Consumption per peak period (kWh) Total consumption QFSEBZ L8I Consumption per week (kWh) Annual consumption L8I Annual CO2 carbon emissions (kgCO2F 1 1 0.0 16.2 10 10 21 21 purpose built water systems and the risk of being exposed to legionella increases in warm, stagnant water, passed to humans via breathing in miniscule, aerosol-like droplets of water. Certain conditions support the growth of bacteria, such as a temperature SBOHFPG$$BTXFMMBTUIFQSFTFODFPGDFSUBJOEFQPTJUTTVDIBT lime-scale, rust, sludge and organic matter can also increase this risk. This is why it is important to control the risk of exposure and do all you can to minimise it by introducing measures that restrict the growth of bacteria and reduce exposure. Traditionally this is done via temperature control, keeping TUPSFEXBUFSBUMFBTUBU$BOEFOTVSJOHEJTUSJCVUFEXBUFSJTTVQQMJFEXJUI $XBUFS $GPSIFBMUIDBSF BUPVUMFUTXJUIJONJOVUF 44 April 2020 www.cibsejournal.com p43-46.CIBSEMagAPR20.indd 44 Advertisement feature 18/03/2020 14:48