Schools are planning to re-open in September and with the recent increased awareness of airborne transmission of Covid-19, there is an urgent need to monitor the situation and to provide guidance on ventilation best practice. This is emphasised by the expected onset of cooler weather when there will be a conflict between maintaining high fresh air ventilation flows and energy consumption and occupant comfort. We will quantify the risk of airborne COVID-19 transmission in schools and evaluate the effectiveness of mitigation measures, by developing techniques to assess the absolute risk of infection in a given indoor space, using field studies in primary and secondary schools, complemented by laboratory experiments and CFD to elucidate the flow patterns responsible for airborne transport. The understanding generated will underpin recent developments in infection modelling to predict the likelihood of airborne transmission within schools. The project will reduce the uncertainties associated with airborne transmission routes and provide evidence to evaluate mitigation measures. The scenarios we will investigate include changes to ventilation, use of screens, classroom lay-out and occupancy profiles. The methodology will facilitate application to offices, restaurants, shops etc. Airborne infection occurs through re-breathed air, the concentration of which can be directly inferred from measurements of CO2. Indoor flow is strongly affected by the locations of windows or vents, the heat rising from occupants/equipment and disturbances caused by people movement. Thus, accurate representations of these processes in the laboratory and CFD are needed to interpret the monitoring data currently collected in schools, which are typically single point measurements.

There are big inequalities in our society, in a range of different things. Regarding health, we know that, in the UK, white people are generally more healthy than non-white people, and rich people are more healthy than poorer people. Beyond health, there are similar inequalities everywhere - in rates of unemployment, in income, in education levels, and so on. What is less well known is how these inequalities vary and interact. For instance, we know there is an ethnicity gap in health, but is that the same for men and women? Is it the same for rich women and poorer women? As we combine characteristics to produce smaller and smaller groups, it becomes clear that the inequalities in our society are complicated. And that complexity matters: it's important that we know who has worse health, so that we can target policies to the right people; it's important that we know who is being failed by our education system, so we can think about how the system could be changed to be more equitable. Fundamentally, in order to improve social justice, we need to first understand who is currently being let down by society. And that needs to be more than just a comparison of broad categories of people. The MAIHDA method is a statistical model that allows us to do this: it lets us to see which combinations of characteristics are associated with advantage, and which are associated with disadvantage. This innovative method has been incrementally developed between 2016 and 2022, and has already informed us about the nature of inequalities in a range of health outcomes. However, the method remains in its infancy, and this grant will refine the method to allow it to be used in situations that it has never been used before. This includes evaluating government policies to see which groups benefit from a particular policy, and which groups benefit less or even are harmed. The project will also allow us to consider how complex inequalities have changed over time, and how they vary from place to place. We will test our methodological refinements using real datasets which will act as exemplars in how these methods could be used going forward, relating to (among other things) obesity, covid-19, and environmental pollutants. We are also keen to expand the use of the method beyond health inequalities. As such, we will collaborate with academics and researchers in academic research centres and non-academic organisations, to implement the MAIHDA methods in other social science subject areas. This will include the analysis of carers, and how being a carer affects different groups of people in different ways. It will include an analysis of water quality in the United States, to see how different groups of people, in different places, are affected by poor-quality, polluted drinking water. And we will consider how educational inequalities vary for different groups of people, to see which groups are being let down by the education sector. Finally, a key part of this grant is training. We want to upskill researchers, in academia and beyond, to be able to use this method and our refinements to it in the future. As such we will produce a wide variety of online training materials, and run both online and in-person training courses, aimed at established academics, PhD students, and non-academic research organisations. These materials will be developed with other stakeholders to ensure that they meet the needs of those organisations and individuals.

Poor air quality is widely recognised to affect human health and wellbeing. Cumulative exposure to pollutants throughout the life course is a determinant for numerous long term health conditions including dementia, heart disease and diabetes, Short term high exposures are shown to exacerbate conditions such as asthma and COPD, increase risks of heart attacks and stroke and influence respiratory infections. The very young, very old and those with pre-existing conditions are most at risk and inequality further increases this; the poorest in society often live in the lowest quality housing in the most polluted areas. Human exposure to air pollutants occurs in both indoor and outdoor environments. Urban air pollution results from a combination of local outdoor sources (e.g. transport, combustion, industry) and regional and large scale atmospheric transport of pollutants. We spend up to 90% of our time indoors and indoor air quality is therefore a significant part of human exposure. Indoor air quality is influenced by the climate, weather and air quality in the external environment in addition to local indoor sources (e.g. microorganisms, chemicals cleaning and personal care, cooking, industry processes, emissions from building materials, heating and mechanical systems) and the building design and operation. In all cases it is the airflows within and between indoor and outdoor locations that enables the transport of pollutants and ultimately determines human exposures. Understanding airflows is therefore at the heart developing effective mitigating actions, particularly in cases where there is limited ability to remove a pollutant source. Being able to predict the influence of airflows enables understanding of how pollutants are likely to move within and between buildings in a city, both under normal day-to-day conditions and in response to emergencies such as heatwaves or wildfires. With the right computational and measurement tools it is then possible to change the design or management of city neighbourhoods enabling better urban flows to reduce exposure to pollutants and also to innovate new ventilation solutions to control the indoor environment in buildings. While there are a number of approaches that already enable assessment of urban flows and indoor flows, these aspects are not currently considered together in an integrated way or focused on optimising environments for health. The Future Urban Ventilation Network (FUVN) aims to address this by defining a new holistic methodology - the Breathing City. This will define a new integrated assessment approach that considers coupled indoor-outdoor flows together to minimise exposure for people within a neighbourhood who are most at risk from the effects of poor air quality. The network will bring together people from a range of disciplines and areas of application with a common interest in improving urban and indoor airflows to improve health. Through small scale research and workshop activities we will advance the understanding of the fluid dynamics that determines the physics of this indoor-outdoor exchange. The network will develop a research programme to address technical gaps in modelling and measuring pollutant transport and how we can use this to determine long and short term exposures to a range of pollutants. We will work collaboratively with industry, policy makers and the public to understand how this approach could change city planning, building design guidance and community actions to enable health based future urban ventilation design and to "design out" health risks for people who are most vulnerable.

The UK Longitudinal Linkage Collaboration (UK LLC) has been set up to bring together data from longitudinal study participants with their routine records. This is done in a secure way to help researchers work to improve health and wellbeing throughout and beyond the COVID-19 pandemic. What does this mean and why is it important? Longitudinal studies gather data about people's lives over time. This data can lead to discoveries that improve people's lives. Linking study data with health and administrative records will help researchers deliver public benefit research. Continued funding of UK LLC will allow us to use what we learned from the pandemic and offer the resource as a long-term service for UK longitudinal research. It will make possible research into our biggest health/socio-economic challenges and widening health inequalities. The large scale, diverse linked data will provide the numbers for researchers to study rarer outcomes and harder-to-reach populations. How does UK LLC work and how is it unique? UK LLC will support a national move to standardise and regulate data access for all Longitudinal Population Studies (LPS). We are a national Trusted Research Environment (TRE) for longitudinal research. A TRE is a secure computer system that allows researchers to analyse data from within the environment. Our TRE holds data from 280,000 study participants from across the UK. The data itself is held within the TRE - it never leaves, and it's never sold on. Data is linked to regularly refreshed NHS and environmental records (eg, air pollution, noise pollution). We have secured approvals to link to employment, earnings, benefits and education records from the UK Government organisations who own this data. We are working with studies to make sure participants are aware of this use of their data and can discuss any concerns with their study team. We know that some studies may choose not to permit all linkage options. This new resource has been made possible by providing an easy and consistent way for studies to join and by centralising our operations. Our processes were built from the ground up with particular focus on safeguards and security. Who is involved in UK LLC? Our partnership includes UK LLC, lead researchers from 24 studies and many other key individuals and organisations working with health data. We will support parts of the UKRI Population Research UK (PRUK) vision to centralise support for studies. This will unlock new scientific opportunities. We have public contributors, including study participants, who form an important part of our existing and planned activities. They focus on representing the views of publics and study participants, working to make sure the way we talk and promote the resource is transparent, clear and demonstrates the public benefit. What will this funding allow UK LLC to do? It will allow us to continue to offer this valuable national resource for research and to make it better. It will enable UK-wide analyses, allowing research results and effects on policies to be measured and compared. We will quickly be able to bring on new and existing study data. As researchers use the resource, it will create an ever-increasing knowledge base to build and improve on. Importantly, we will be able to learn from the coronavirus pandemic and use the TRE to support a quick response to future crises and NHS/UK Government needs. Continued funding will deliver our three core objectives to a) make UK LLC a globally unique resource in the breadth and depth of its capability, b) provide a route for studies to move to working with their data in TREs and c) empower researchers to get the best out of the available data and continue to build and grow its capacity and improve its quality as a high value research resource for the UK. By bringing this data together, we're providing a way for research to meet the needs of people across all our communities.

The aim of this network is to bring together interdisciplinary expertise to address the problem of air quality in schools. The future health of our nation and indeed all human society depends on educating children in healthy environments. The Tackling Air Pollution at School (TAPAS) network focuses on that vulnerable section of every society - school children and their environment. Our vision is to create and develop a menu of options that can be introduced into schools to provide an environment free of pollutants and in harmony with nature, so that children have a fulfilling and healthy educational experience. These products need to be effective, inexpensive and, where possible, educational: i.e. they should involve the children in an understanding of their environment and provide them with an opportunity to engage with it in social, scientific and behavioural terms. We have chosen to focus on schools and school children for the following reasons. Children are a particularly vulnerable section of society. They are physiologically less able to regulate their temperature and are more susceptible to exposure to air pollution than adults. Among the vulnerable groups in society school pupils will experience the impact of poor air quality for the longest period into the future. Recently, over 2000 schools in the UK were identified as being in 'pollution hotspots' where air pollution exceeds WHO limits. From a practical viewpoint, working in schools has many advantages. School keep records on student attendance and pupils which provide information on absences related to health. They also have data on room occupancy, pupil activities (e.g. PE, meals) and movement through the school. This information is essential to determine personal exposure. Additionally, schools offer a wide variety of spaces including labs, meeting halls, dining areas as well as classrooms, each with different ventilation and indoor sources of pollution. The ability of schools to mitigate exposure to pollution is hampered by lack of knowledge. For example, the impact of idling vehicle engines near school while dropping off and collecting children on exposure in the playground or on indoor levels of NOx and particulate matter (PM) is unclear, making it impossible for schools to decide whether to ban idling or not. Our interdisciplinary team consists of experts in indoor and outdoor pollution, air pollution modelling, data science, building design and ventilation, education, social behaviour and health impacts. This will allow this network to address the critical issues associated with pollution in schools by offering a menu of solutions. We also propose to include a significant educational component so that pupils will learn about the impacts of poor air quality and take this knowledge with them as they grow up, thereby producing a lasting change in society. Schools also accommodate children with special educational needs and disabilities (SEND) who are even more vulnerable and who often require special environmental conditions. Furthermore, there are currently a wide range related activities concerning indoor environmental quality in schools that this network will bring together for the first time in a coordinated fashion.