The Authorising Engineer (Water): Questions Which Shape Our Future Needs

Published on 07/11/2022 | by Waterline Admin

As featured in Waterline Summer 2022

The Authorising Engineer (Water):
Questions Which Shape Our Future Needs

David Harper, Harper Water Management Group Ltd.

Drinking water storage and distribution systems have been challenging our health and wellbeing for centuries and the stellar rise of opportunistic waterborne pathogens from this niche man-made environment has been noted since the 1950s (Schiavone, 1957). Despite more than 70 years of learning there remains a gap between knowing what a problem may be, and the installation, commissioning and operation of a “safe” in-premise water system (Proctor, 2022). Each water installation is unique, yet similar technical design and engineering problems, poor operational practices, bad behaviours by users and lack of multi-disciplinary skills in Water Safety Groups are commonly found.

The Institute of Healthcare Engineering and Estate Management (IHEEM) is an independent organisation providing guidance and development for engineers and estate managers in the healthcare sector. IHEEM have championed the role of Authorising Engineer (AE) in healthcare organisations (IHEEM, 2021) which aligns to the Department of Health’s Health Technical Memorandum 00, Policies & Principles of Healthcare Engineering (DOH, 2014). Building robust and scrutinised engineering into the health sector by having an AE (Water) to help guide and assess the design, installation, operation and audit of water systems from an engineering and environmental perspective is a serious undertaking in improving water quality. It is critical that the AE (Water) remains independent of the operational structure of the healthcare organisation, with particular regard to the audit process. IHEEM have recognised the import role of an Authorising Engineer (Water) since 2016 and have eleven registered individuals active today. However it is not so clear cut how such independent support should be adopted in non-healthcare sectors, which is surprising when the majority of legionellosis cases are contracted from non-healthcare facilities. The European Centre for Disease Prevention & Control (eCDC, 2022) have just published their annual Legionnaires’ Disease report for 2020, and despite a small decrease of cases during the COVID-19 restrictions there were 19 outbreaks with 10 of these from non-healthcare related sources. It would be prudent for accommodation sites such as hotels, cruise ships, campsites and other public facilities such as leisure centres and spas to have such AE (water) controls and guidance in place.

Improvements in water safety in both healthcare and nonhealthcare has been slow, hampered by lack of education and training, outsourcing to unspecialised and unsupervised third-parties, lack of necessary priority and budget and little evidence-based or experienced decision making. Often there is too high a priority on design, appearance, magic gadgets and cost-savings which have led in many cases to regression in water quality. Lessons have not been learnt or applied. Sadly, waterborne environmental pathogens which readily create and reside within biofilms are inherently resistant to systemic biocides and heat treatments, are a genetic swapshop for antibiotic resistance, are present in both healthcare and non-healthcare water systems and present the greatest risk to users. How can the Water Management industry best support improvements in safe water for drinking, bathing and recreation? Will there be registered Authorising Engineers (AEs) embedded in non-healthcare water management structures? Health and safety legislation tends to favour a risk-based approach, but with the critical nature of in-premise plumbing systems and an unsuspecting and trusting user population, the operation of a water system comes with heavy responsibilities. What will it take to get our water systems under control, and what skills will both the AE (Water) and Water Management/Safety Groups need for the future?

Of growing importance, is the need for the AE (Water) to be independent from both service and/or solution providers and for Water Safety Groups to engage external and independent expertise. It is not appropriate for the same individual or company to be providing services that have a conflict of interest at the same client site. For example, the individual or company completing the risk assessment should not then be developing the water safety plan, nor should the individual or company undertaking the water sampling and/or testing be providing a product such as systemic biocides or filtration or providing a monitoring software, for example. Here lies both conflict and bias. To be a registered AE (Water) in England you have to be a member of IHEEM and are approved only after review and scrutiny of the IHEEM team. Re-registration is required every 3 years. Clarity in recognising conflict of interest and ensuring no partiality or mis-practice must be recognised by those engaging the services of third parties to complete water management and hygiene services. “Independent” does not mean safe, so diligent examination of experience, ability and reputation is also needed. Having a fresh pair of objective eyes to assess independent evidence, give advice, inspect documentation, complete audits, review priorities and plans, support trouble-shooting, input their experience on all aspects of water management could prevent illness, reduce mortality and, in case of litigation, be protectively robust. How can the industry better recognise “independence” and improve both water safety and compliance in the future? How can service providers be better governed and how will this lead to better water management practice and hygiene results?

Good management and operation of an in-premise water system requires an inter-disciplinary approach (Proctor, 2022). Engineering knowledge and practical expertise is critical, but to grasp relevant microbiological hazards requires good understanding of the concerning pathogen(s), along with relevant water hygiene know-how which links to user-behaviour and transmission risks. Occasionally there will be an experienced engineer who has good working water microbiological knowledge and understanding, and occasionally there will be an infection preventionist who has good working engineering knowledge of the built environment. However these “unicorns” are rare. Lack of experience or omission in these areas will lead to a lower quality water system and sub-optimal management (Garrison, 2016). Within Water Safety Groups there is often a disconnect between recognising relevant hazards and risks and putting effective control measures in place. Not enough is done to assess problems properly, rather a knee-jerk reaction to “fix” without exploring and understanding all the issues and parameters affected. There is an over-dependence on chemical biocide solutions which rarely offer a long term sustainable solution (Arrigo, 2022; Thom, 2022; Hegarty, 2022; Jiang, 2022; Lane, 2022; Sabatini, 2022; Girolamini, 2022; Ma, 2022) unless considerable investment and time is spent completing remedial engineering measures first. A forensic finger-tip search to both identify and remove all dead legs, mitigation of any hydraulic balancing issues, ensuring non-return valves are fitted and working correctly, regular maintenance for plumbed in equipment, removal of inappropriate fittings and materials of construction (Wang, 2022, Proctor, 2018), temperature control (Cazals, 2022), sufficient flushing of under-used outlets or ideally their complete removal. Sometimes, once all these needed actions have been undertaken, there is no longer a need for systemic biocides – “engineer the problem out” is the best adage. If it is not possible to control temperatures, then it is likely that biocides will be needed, but as with any water system changes there should be a risk assessment completed before selection and installation with agreement to proceed from the Water Safety Group. Solutions are not always selected based on independent published data from real-life water system operations, and little is done to verify the efficacy of chosen solutions once installed or followed over years in steady state operation. Where is the independently published evidence? There needs to be a more rigorous, critical and disciplined approach to implementing appropriate and sustainable control measures to avoid costly mistakes. Unintended consequences may reflect inadequate multi-disciplined team consideration in the preparation and selection phase. Implementation of Water Safety Plans in all types of buildings and water systems has grown since the World Health Organisation publication in 2005 (WHO, 2005, 2010). Improvements are seen when a Water Safety Plan and cross-functional Water Safety Group approach is adopted for water system management. Good guidance here is not lacking (BSI, 2020), and should be embraced.

Steady state operational data measurement and management remains a gap. There are excellent opportunities to improve the quality and quantity of data whilst reducing costs through use of sensors and software. Temperature and flow measurements are critical and identify where the primary control measures of temperature control are outside of scope, and flags water outlets that are not being used sufficiently and therefore can be removed or captured on a flushing list. One way to rapidly demotivate skilled plumbing and technical engineering staff is to fill their day with the drudge of taking water temperatures or flushing outlets, worse if collected on paper. Due to resource restrictions, often the only action taken is to measure the out of specification data point again the following month rather than triggering skilled personnel to investigate the problem, develop a corrective action plan with identified resources and bring to the Water Safety Group meeting for focused discussion and agreement. Working smarter, more cost-effectively and ensuring sustainable control requires better access to data. This includes microbiological monitoring, which is relatively expensive – perhaps monies may be better spent on improving water system infrastructure? Culturing water samples for waterborne microorganisms is inaccurate (Chiang, 2022; Delaney, 2022), and such variance would not be tolerated from an accurate digital thermometer or chlorine monitor. Plate culture methods are still considered the “Gold Standard” despite the complexity of getting a representative sample via aseptic technique, correct storage and transportation conditions to an accredited laboratory, and even then, a high chance that the organism of concern does not grow on the plate. Legionella is notoriously difficult to grow in the laboratory, particularly from water systems using continuous or shock systemic biocides. This is due to the reluctance of free-living cells exposed to environmental stresses, such as systemic disinfection, to show themselves on a culture plate despite optimal growth conditions. It is important to note that receiving a “Not Detected” culture count in isolation does not support the Water Safety Group to understand how a water system is performing or if control measures are effective. If conditions are conducive for growth, urgent action is needed whether the culture results are positive or negative, and microbiological culture is not a superior indicator or replacement for real-time temperature, chlorine, flow and throughput. To better determine a microbiological problem, and importantly how that may apply to the extent of human risk, there are more accurate, more specific and more sensitive molecular tests such as polymerase chain reaction (PCR) that can be employed to determine the effectiveness of engineering remedial measures. Results are returned the next day with relatable data to assist decision-making. There is plenty of molecular test kit about, but few laboratories have embraced the UKAS accreditation schedule for their molecular methodology in water testing. For an AE (Water) or a Water Safety Group to assure water safety from culture, the data returned must be considered one part of a bigger picture in order to support decision making or risk assessment. There is a responsibility to best understand the operation conditions and risk from a water system. Culture data can give a false “Green Light” and it may be appropriate to use presence/absence tests to give an interim picture of progress following implementation of remedial measures. Molecular testing should be more widely adopted into standard practice and written into guidance. Is continued use and dogged recognition of traditional cell culture plate counts driven by the desire to have negative or low count results? Is lack of understanding, confusion over interpretation of the results and implementation of the data generated restricting uptake of alternative technologies?

Legionella remains one of the most important waterborne pathogens and a major challenge for those managing a water system. Sixty three different species are now recognised, the newest being Legionella antarctica which was recognised last year (Shimada, 2021) and confirms that the cold water risks should be noted with this tolerant strain. Risk assessments mainly focus on Legionella pneumophila, or even more narrow with Legionella pneumophila serogroup 1. Whilst Legionella pneumophila is accountable for the majority of legionellosis detected, there are many non-pneumophila species that can cause infection and if there are conditions conducive for the growth of one Legionella species, then the water system is likely capable of supporting growth of others. There is increasing anecdotal evidence that L. anisa is more prevalent than L. pneumophila in samples analysed in UK laboratories, but this needs to be considered in conjunction with the vagaries of the current ISO 11731 culture method. Every signal of Legionella presence in a water system should be taken seriously, prioritised, investigated further and risk assessed for remedial measures. For other critical waterborne pathogens (Falkinham, 2015), such as Pseudomonas aeruginosa, Stenotrophomonas maltophilia and non-tuberculous mycobacteria, which are increasingly problematic in both healthcare and non-healthcare settings, many of the traditional water hygiene mantras remain true. Think: keep it clean, keep it hot, keep it cold, keep it moving, keep it documented. However, Pseudomonas is not the same beast as Legionella, and the risk assessment is quite different. Despite recent publications from the British Standards Institute (BS 8580-1: 2019; BS 8580-2: 2022; BS 7592: 2022; BS 8680: 2020; BS PD855468: 2015) the correct assessment and inclusion in on-site risk assessment reports for “Non- Legionella Waterborne Pathogens” has been left lacking. There remains a significant knowledge gap which must be addressed with urgency. Outbreaks from Pseudomonas aeruginosa colonised taps has been reported since the 1960s, and yet the same problems continue to be reported. An important learning from the Glasgow Cupriavidus pauculus outbreak is that there are unusual and unexpected outbreaks (Inkster, 2021; Inkster 2022), and it is critical to have a multiskilled team approach and understanding for risk assessment to capture the importance and mount effective preventative responses. Certainly risk assessment and remedial measures at the periphery of the water system (Apanga, 2022; Butler, 2022), including drains and traps, are inadequately covered in risk assessments and water safety plans. Risk assessment by a multi-skilled team is needed and must come before any change or addition to the water system is adopted as standard work practice.

The COVID-19 pandemic will leave its legacy imprinted on our water systems for many years to come (Aw, 2022; Bédard, 2018; Cassell, 2021, Chen, 2020 (a, b); Faust, 2021; Rhoads, 2022; Ye, 2022; Zhang, 2021 a & b; Zlatanovic, 2017) with the effects of stagnation leading to established immovable biofilms (Fleming, 2016 & 2020). A plethora of guidance was released to support water management practice both during lockdowns where there was little or no use, and for bringing buildings back on-line and into routine use (CDC; CIEH a & b; EPA a & b; ESGLI; HSE; LCA; WMSoc) What publications can we expect to see as a result? For many flushing will not be the answer (Hozalski, 2020; Nisar, 2020; Proctor, 2020; Totaro, 2018). Many supporting guidance documents were released, including the helpful and practical based ESGLI ones. Systemic shock and continuous biocide treatments are not the simple fix that many hoped for and can at worst lead to biofilms compiled of biocide-tolerant microorganisms many of which are multi-drug resistant opportunistic pathogens (Zhong, 2022). Water systems which have hydraulic / balance problems, where temperatures are not achieved in all areas and at all points of use, have dead legs and little used outlets will be an indication for where sub-lethal biocide levels will equally have less circulation, contact and impact. We should all reflect on the level of immune function in the general public who are “out and about” and may be exposed to unexpected water pathogens in the community (Alhuofie, 2021; Orkis, 2018), at a hotel (Barksey, 2019), an outdoor water fountain (Faccini, 2020; Steen, 2021), from paddling pools (Carter, 2019), using public transport (Federigi, 2022; Ulger, 2022) the windscreen washer of vehicles (Politi, 2022), in their own homes (Filippis, 2018; Ricci, 2021; Ryu, 2017; Schumacher, 2020), showering (Hayes-Phillips, 2019), using CPAP devices (Schnirman, 2017), dishwashers (Matsuki, 2022; Zupancic, 2019), chilled water dispensed from the fridge (Villarreal, 2022) or an aromatherapy spray (Gee, 2022). The biggest threat from water systems in healthcare to users is antibiotic resistance. Biofilms in water systems are reservoirs of antibiotic resistance (Tiwari, 2022). Waterborne pathogens cause unnecessary illness and death, yet we have the means to control them. Indeed it has been proven that waterless healthcare in high risk patient areas is not only possible but reduces infections and antibiotic usage (De- Las-Casas-Camara, 2022). For many years we have seen increased requests for handwash basins in order to support handwashing campaigns. Yet the use of alcohol gel has reduced the need and we are left with under used outlets which are a risk for users. With such clear evidence the water safety groups in hospitals should be pushing to remove outlets, to place clinical handwash basins outside the room for all sensitive, high risk or clean areas within hospitals. In non-healthcare buildings to channel the throughput of water through fewer outlets will no doubt lead to improved water safety and easier management. Education needs to impact and change practice on-site. If you only have a small budget, spend it on good education as it will bring the best costsavings.

We have a long way to go before getting in-premise water quality consistently under control, and despite more than 50 years’ experience in engineering various problems out of water systems and where there is little I have not seen or experienced, there are new challenges with different and more complex threats ahead of us. Problems which increasingly require the multi-skills of an interdisciplinary approach. Microorganisms have had 4 billion years to hone their skills in adapting to every environment on earth, they have the advantage on us. Antimicrobial resistance, water shortages, carbon zero and climate change are no longer on the horizon, but at our door. May we all rise to and recognise the water quality and safety challenges of the future.

References can be made available upon request

Diary Dates & Events

Grime Scene


Following on from the successful Grime Scene competition, we have decided to continue the theme for another year, but with a twist. This year, we are asking for photographs of the grimiest pictures you can find accompanied with another photograph of how the ‘scene’ has been improved by your maintenance or cleaning.

We will display the photographs in each of the Waterline editions throughout 2024. The ‘most improved’ picture will be chosen by WMSoc members via an online vote. The winner will receive a £25 Amazon Gift Voucher after the Winter 2024/25 edition has been published.

Please send your photographs to:
[email protected].

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