Improved design and operations of building water systems to reduce health risks caused by water & energy conservation and extended shutdowns

改进建筑供水系统的设计和运行，以减少水造成的健康风险

• 批准号: RGPIN-2021-04341
• 负责人: Prévost, Michèle
• 金额: $ 3.79万
• 依托单位: École Polytechnique de Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=754674
• 关键词: Improved; design; operations; building; water

Stagnation of water in building water systems can cause elevated concentrations of toxic metals and pathogens such as Legionella pneumophila, Pseudomonas aeruginosa and Non Tuberculus Mycobacteria. Pathogens can be amplified within building water systems and cause outbreaks and community acquired disease. Legionella is now the most common cause of drinking water associated outbreaks and Legionnaire's disease rates are increasing rapidly. Maintaining water quality in buildings is a growing challenge because of the unintended consequences of water and energy conservations measures that have been shown to increase health risks. Such measures are highly justified but have unfortunately been implemented to legacy building systems without regard for water quality, often causing severe water quality losses. Recently, the SARS-CoV-2 global pandemic forced extended closures of a staggering number of buildings across Canada with extreme stagnation causing unsafe water. The research program aims to provide the evidence to base recommendations to improve the design and operations of building water systems and ensure the provision of safe water. The widespread implementation of low flow devices and thermostatic valves impacts water quality building in water systems. Energy conservation measures for hot water systems in large buildings such as heat exchangers, lowering of temperature set points have led to the proliferation of Legionella causing documented cases and fatalities in Canadian health care facilities. The consequences of these conservation measures is poorly documented and need to be quantified. The research program will address the key knowledge gaps through a combination of field investigations, pilot and bench scale assays, laboratory studies, risk analysis and regulatory impact investigations. Field studies will document the prevalence of pathogens, microbial diversity and the presence of toxic metals in building water systems across Canada using innovative sampling strategies. Intervention field studies will document the impacts of commissioning procedures and water conservation retrofits. Pilot studies will focus on the interplay between materials, water quality and water usage. Laboratory and bench-scale studies will quantify the production of aerosols and colonization potential of low flow faucets and showers to quantify the exposure pathways. Risk analysis (QMRA) models will be used to guide the selection of alert and action levels and define optimal regulatory frameworks. Research results will provide actionable evidence to reduce health risks to their occupants and will be conducted in close collaboration with utilities, regulators and associations with the clear intent of providing: a basis for streamlined and effective guidance and regulations, cost effective environmental monitoring programs, modifications of the building code, drinking water compatible material certification and reviewed building water system design approaches.

建筑供水系统中的水停滞会导致有毒金属和病原体（例如嗜肺军团菌、铜绿假单胞菌和非结核分枝杆菌）浓度升高。病原体可以在建筑供水系统中繁殖并导致疾病暴发和社区获得性疾病。军团菌现在是饮用水相关疾病爆发的最常见原因，并且军团菌的发病率正在迅速增加。维持建筑物内的水质已成为一项日益严峻的挑战，因为节水和节能措施会产生意想不到的后果，而这些措施已被证明会增加健康风险。这些措施是非常合理的，但不幸的是，这些措施在不考虑水质的情况下应用于遗留建筑系统，常常造成严重的水质损失。最近，SARS-CoV-2 全球大流行迫使加拿大各地数量惊人的建筑物长期关闭，水源极度停滞，导致用水不安全。该研究计划旨在为改善建筑供水系统的设计和运营并确保提供安全用水的建议提供证据。低流量装置和恒温阀的广泛使用影响了供水系统的水质建设。大型建筑热水系统（例如热交换器）的节能措施、温度设定点的降低导致了军团菌的扩散，导致加拿大医疗机构中记录的病例和死亡。这些保护措施的后果鲜有记录，需要量化。 该研究计划将通过实地调查、中试和小规模试验、实验室研究、风险分析和监管影响调查的结合来解决关键知识差距。实地研究将使用创新的采样策略记录加拿大各地建筑供水系统中病原体的流行情况、微生物多样性以及有毒金属的存在情况。干预现场研究将记录调试程序和节水改造的影响。试点研究将重点关注材料、水质和用水之间的相互作用。实验室和实验室规模的研究将量化气溶胶的产生以及低流量水龙头和淋浴器的定植潜力，以量化暴露途径。风险分析（QMRA）模型将用于指导警报和行动级别的选择，并定义最佳监管框架。研究结果将提供可操作的证据，以减少居住者的健康风险，并将与公用事业公司、监管机构和协会密切合作，其明确的目的是提供：简化和有效的指导和法规的基础、具有成本效益的环境监测计划、建筑规范的修改、饮用水兼容材料认证和审查的建筑给水系统设计方法。