Residential indoor air quality interventions through a social-ecological systems lens: A systematic review

Indoor air quality (IAQ) is an important consideration for health and well-being as people spend most of their time indoors. Multi-disciplinary interest in IAQ is growing, resulting in more empirical research, especially in affordable housing settings, given disproportionate impacts on vulnerable populations. Conceptually, there is little coherency among these case studies; they traverse diverse spatial scales, indoor and outdoor environments, and populations, making it difficult to implement research findings in any given setting. We employ a social-ecological systems (SES) framework to review and categorize existing interventions and other literature findings to elucidate relationships among spatially and otherwise diverse IAQ factors. This perspective is highly attentive to the role of agency, highlighting individual, household, and organizational behaviors and constraints in managing IAQ. When combined with scientific knowledge about the effectiveness of IAQ interventions, this approach favors actionable strategies for reducing the presence of indoor pollutants and personal exposures

Improving indoor thermal comfort, air quality and the health of older adults through environmental policies in London

In this work we evaluate the potential of selected environmental strategies in reducing air pollution and summertime indoor overheating. Associated changes in mortality rates are also calculated for older adults in London. Reducing these risks for vulnerable groups is an immediate priority and given that seniors spend most of their time indoors, our focus is on strategies that prioritize the transformation of residential environments for indoor thermal comfort and air quality improvements. For each strategy, we develop specific scenarios related to building adaptations and test potential reductions on indoor overheating and pollutant exposures from outdoor sources (PM2.5), as well as on senior mortality through the CRAFT tool (Cities Rapid Assessment Framework for Transformation). We then pick the scenarios with highest impacts on mortality, aiming to formulate effective policy recommendations for Greater London. Preliminary results suggest that environmental policies related to the installation of shading could have the highest reduction in heat and pollution-related senior mortality, followed by moderate effects due to building insulation retrofits and the greening of roofs. With an increasing ageing population in the UK and beyond, our work highlights the need for city-level policies to address building modifications, considering the importance of indoor spaces for older adults

Monitoring summertime indoor overheating and pollutant risks and natural ventilation patterns of seniors in public housing

Indoor heat and air pollution pose concurrent threats to human health and wellbeing, and their effects are more pronounced for vulnerable individuals. This study investigates exposures to summertime indoor overheating and airborne particulate matter (PM2.5) experienced by low-income seniors and explores the potential of natural ventilation on maintaining good indoor thermal conditions and air quality (IAQ). Environmental and behavioural monitoring and a series of interviews were conducted during summer 2017 in 24 senior apartments on three public housing sites in NJ, USA (1930s’ low-rise, 1960s’ high-rise and LEED-certified 2010s’ mid-rise). All sites had high exposures to overheating and PM2.5 concentrations during heat waves and on regular summer days, but with substantial between-site and between-apartment variability. Overheating was higher in the 30s’ low-rise site, while pollutant levels were higher in the 60s’ high-rise. Mixed linear models indicated a thermal and air quality trade-off with window opening (WO), especially in some ‘smoking’ units from the older sites, but also improved both thermal and PM2.5 concentration conditions in 20% of the apartments. Findings suggest that with warmer future summers, greater focus is needed on the interdependencies among (1) thermal and IAQ outcomes and (2) technological and behavioural dimensions of efforts to improve comfort for vulnerable occupants

Passive Strategies to Improve Thermal Conditions in a Care Home in London, UK

This work assesses the current and future risk of summer thermal discomfort of older adults in a refurbished care home in London, UK. It further explores the potential of passive adaptations to improve indoor environmental conditions. Temperature and relative humidity data from continuous monitoring during summer 2019 were used to calibrate a building performance simulation model of the care home. Simulation outputs from two bedrooms and two lounges under the current (2019) and future climate (2080s with 90th percentile probability, high-emissions scenario under the UK Climate Projections 2009) were analyzed to evaluate the risk of indoor overheating and humidity discomfort, and to test the effectiveness of adaptation scenarios related to window operation and external shading. Results showed a high risk of exposure to high indoor temperature and low humidity under the current climate, which are expected to worsen in the future. Regarding the effect of passive adaptations, it was found that the highest potential decline in overheating and dry air incidence could be achieved through a combination of secured window opening at night and closing of external shutters during the day; yet this was compromised by an increased risk of humid air. Results further indicated that these strategies are not adequate under a future high-emissions climate scenario, which suggests that care homes need to combine passive and active ventilation to maintain indoor environmental comfort and reduce anticipated cooling demand

Assessing the Current and Future Risk of Overheating in London’s Care Homes: The Effect of Passive Ventilation

The warming climate causes adverse effects on thermal comfort and health, especially for vulnerable older adults. This study assesses the current and future risk of summertime overheating in London’s care homes and explores the potential of passive ventilation on reducing these risks. Analysis is based on temperature monitoring of two care settings and on thermal simulation models of future conditions with and without passive ventilation strategies. Results show high overheating exposures for both care homes, with temperatures averaging 31-35 0C by 2050. Passive ventilation can substantially reduce these exposures, but a successful approach depends on time of day, duration and window characteristics. Dynamic window opening based on lower outdoor temperatures and indoor temperature exceedance of 22 0C is the most beneficial approach for both settings now and in the future. The study demonstrates the effectiveness of affordable building adaptations for reducing heat stress in senior care homes

The CUSSH programme: supporting cities’ transformational change towards health and sustainability [version 2; peer review: 2 approved]

This paper describes a global research programme on the complex systemic connections between urban development and health. Through transdisciplinary methods the Complex Urban Systems for Sustainability and Health (CUSSH) project will develop critical evidence on how to achieve the far-reaching transformation of cities needed to address vital environmental imperatives for planetary health in the 21st Century. CUSSH’s core components include: (i) a review of evidence on the effects of climate actions (both mitigation and adaptation) and factors influencing their implementation in urban settings; (ii) the development and application of methods for tracking the progress of cities towards sustainability and health goals; (iii) the development and application of models to assess the impact on population health, health inequalities, socio-economic development and environmental parameters of urban development strategies, in order to support policy decisions; (iv) iterative in-depth engagements with stakeholders in partner cities in low-, middle- and high-income settings, using systems-based participatory methods, to test and support the implementation of the transformative changes needed to meet local and global health and sustainability objectives; (v) a programme of public engagement and capacity building. Through these steps, the programme will provide transferable evidence on how to accelerate actions essential to achieving population-level health and global climate goals through, amongst others, changing cities’ energy provision, transport infrastructure, green infrastructure, air quality, waste management and housing

Developing a programme theory for a transdisciplinary research collaboration: Complex Urban Systems for Sustainability and Health [version 1; peer review: 2 approved]

Background: Environmental improvement is a priority for urban sustainability and health and achieving it requires transformative change in cities. An approach to achieving such change is to bring together researchers, decision-makers, and public groups in the creation of research and use of scientific evidence. / Methods: This article describes the development of a programme theory for Complex Urban Systems for Sustainability and Health (CUSSH), a four-year Wellcome-funded research collaboration which aims to improve capacity to guide transformational health and environmental changes in cities. / Results: Drawing on ideas about complex systems, programme evaluation, and transdisciplinary learning, we describe how the programme is understood to “work” in terms of its anticipated processes and resulting changes. The programme theory describes a chain of outputs that ultimately leads to improvement in city sustainability and health (described in an ‘action model’), and the kinds of changes that we expect CUSSH should lead to in people, processes, policies, practices, and research (described in a ‘change model’). / Conclusions: Our paper adds to a growing body of research on the process of developing a comprehensive understanding of a transdisciplinary, multiagency, multi-context programme. The programme theory was developed collaboratively over two years. It involved a participatory process to ensure that a broad range of perspectives were included, to contribute to shared understanding across a multidisciplinary team. Examining our approach allowed an appreciation of the benefits and challenges of developing a programme theory for a complex, transdisciplinary research collaboration. Benefits included the development of teamworking and shared understanding and the use of programme theory in guiding evaluation. Challenges included changing membership within a large group, reaching agreement on what the theory would be ‘about’, and the inherent unpredictability of complex initiatives

Collimation for the LHC high intensity beams

The unprecedented design intensities of the LHC require several important advances in beam collimation. With its more than 100 collimators, acting on various planes and beams, the LHC collimation system is the biggest and most performing such system ever designed and constructed. The solution for LHC collimation is explained, the technical components are introduced and the initial performance is presented. Residual beam leakage from the system is analysed. Measurements and simulations are presented which show that collimation efficiencies of better than 99.97 % have been measured with the 3.5 TeV proton beams of the LHC, in excellent agreement with expectations.peer-reviewe

Understanding Urban Green Space Usage through Systems Thinking: A Case Study in Thamesmead, London

Copyright: © 2022 by the authors.Urban green spaces provide environmental, economic, societal and health benefits to cities. However, policy and planning interventions aiming to improve usage have often led to unintended consequences, including, in some circumstances, an actual decline in usage. Previous research has identified factors influencing the use of urban green space, more often with a focus on the ‘quality’ and physical features of the space, rather than on the broader social factors. This study aims to unpack the complexity of factors that influence the use of urban green space through the application of Systems Thinking. A qualitative mixed-method approach integrating System Dynamics with rapid ethnography was adopted to elicit the views of local residents in Thamesmead, London. A thematic analysis of interviews was undertaken to systematically map the causal relations between factors, which were compared to wider stakeholders’ views. Our findings highlight the relevance of dynamics and social influences on the use of green space, which include social interactions and stewardship, health conditions, availability of services and amenities. These are factors that are underexplored in the literature and, sometimes, overlooked in urban green space policy by decision-makers. We infer that attendance of urban green spaces requires time, which may be occupied in other practices determined by local conditions and needs. Expanding the spatial and temporal boundaries of investigation, wider than debates on ‘quality’, should, in our view, increase the chances of identifying critical influences and foster an increased use of green space.Wellcome Trust (CUSSH project, ref. no. 209387/Z/17/Z); U.K. Natural Environment Research Council (CAMELLIA project, ref. no. NE/S003495/1)

Effect of heatwaves on PM2.5 levels in apartments of low-income elderly population. A case study using low-cost air quality monitors

Heatwaves are known to result in negative health effects in general and especially in vulnerable populations. At the same time, the effect of high outdoor temperatures on indoor air quality is largely unknown. To start filling this knowledge gap, we recruited 24 seniors from 3 low-income housing sites in Elizabeth, NJ, to participate in a study, during which we deployed consumer-grade sensors in their apartments to monitor airborne particulate matter (PM2.5) and air temperature. Additionally, one empty apartment, used as a control, and an outdoor station were set up with the same type of sensors. Measurements were performed from July to September 2017. During this period, there were seven days when outdoor temperatures exceeded 90 °F (32 °C), our criterion for heatwave days. First, we found that the average hourly indoor PM2.5 levels varied among apartments and were greatly affected by the presence of smokers. During non-heatwave days, in apartments without smokers, the hourly median PM2.5 concentrations ranged from 4 μg/m3 to 12 μg/m3, while in apartments with smokers, the hourly median PM2.5 concentrations ranged from 14 μg/m3 to 90 μg/m3. More importantly, the indoor PM2.5 levels were higher (p < 0.05) during heatwave days. A statistically significant increase was observed for all apartments, regardless of the building site, presence of smokers, or type of air conditioning. Moreover, since human activity contributes to indoor PM2.5, we separated the data into an active period (6:00 a.m. to 10:00 p.m.) and the rest period (10:00 p.m. to the next day 6:00 a.m.); the PM2.5 increase during heatwaves was statistically significantly higher for both periods. Overall, our data suggest that higher ambient temperatures could be an important factor for indoor PM2.5 exposures. Future investigations should consider several exposure-modifying factors, such as the use of windows and AC, for a more accurate assessment of outdoor conditions affecting indoor exposures