#7.1 - Henry Burridge: Evaluating the Impact of School Ventilation on Learning and Health

Part 1
Henry Burridge - Is a Senior Lecturer in the Fluid Mechanics section in the Department of Civil and Environmental Engineering at Imperial College London.

Henry has a background in Mechanical Engineering and a PhD in Civil and Environmental Engineering from Imperial College London.

Following his PhD, Henry has worked as a Post Doctoral Researcher at the University of Cambridge, initially in the Engineering Department and then in the Department of Applied Mathematics and Theoretical Physics.

Henry's research focuses on fluid mechanics for the built environment. And includes the practical application of this understanding to the human- and climate change-focused ventilation of buildings, amongst much more.

He  is a Co-Investigator for the Tackling Air Pollution At Schools (TAPAS) network and the Future Urban Ventilation Network (FUVN): The Breathing City

Henry primarily applies his expertise to indoor air quality and ventilation, presenting evidence to the Common Select Committee for Health and Social Care and contributing to the Technical Advisory Panel on Ventilation for the Government's Cabinet Office, and being an author for the 'Indoor Air Quality and Health' chapter within the Chief Medical Officer’s annual report 2022: air pollution.

A focus area for him is schools, and Henry currently leads the initiative towards School Air Quality Monitoring for Health and Education via the SAMHE project, seeking to establish large-scale monitoring in UK schools and engage pupils with their school environment.

He is a Co-Investigator on  CO-TRACE, investigating COVID-19 transmission in schools. And joint Principal-Investigator of the Department for Education's pilot project investigating the 'Changes In the Ventilation Of Schools when monitoring CO2.

Needless to say much of our discussion in the podcast was about schools, the challenges that particular sector faces, the impact of air quality on children and teachers and how projects like SAMHE are engaging kids in the science of air quality. We discussed much more of course including the value of observatories for indoor air quality.

Henry Burridge - https://www.imperial.ac.uk/people/h.burridge
SAMHE - https://samhe.org.uk/
FUVN - https://breathingcity.org/
Chief Medical Officer’s annual report 2022: air pollution - https://www.gov.uk/government/publications/chief-medical-officers-annual-report-2022-air-pollution

Chapters

• 0:15 Air Quality in Schools
• 15:39 Ventilation and Air Quality in Schools
• 25:30 School Ventilation and Air Quality Monitoring
• 46:19 Air Quality and Its Interconnections

Transcript

Simon: 0:15

Welcome to Air Quality Matters, and this is a conversation with Henry Burridge, a senior lecturer in the fluid mechanics section in the Department of Civil and Environmental Engineering at Imperial College London. Henry has a background in mechanical engineering and a PhD in civil and environmental engineering. Following his PhD, henry has worked as a postdoctoral researcher at the University of Cambridge, initially in the engineering department and then in the department of applied mathematics and theoretical physics. Henry's research focuses on fluid mechanics for the built environment and includes the practical application of this understanding to human and climate change focused ventilation of buildings, amongst much more. His co investigator for the tackling air pollution at schools, tapas network and the future urban ventilation network and the breathing city. Henry primarily applies his expertise to indoor air quality and ventilation, presenting evidence to the common select committee for health and social care and contributing to the technical advisory panel on ventilation for the government's cabinet office, and being an author for the indoor air quality and health chapter within the chief medical officer's annual report of 2022.

Simon: 1:43

Air pollution. A focus area for him is schools, and Henry currently leads the initiative towards school air quality monitoring for health and education via the SAMI project, seeking to establish large-scale monitoring in UK schools and engaging pupils with their school environment. His co-investigator on co-trace investigating COVID-19 transmissions in schools, and joined principal investigator of the Department of Education's pilot project investigating the changes in ventilation of schools when monitoring CO2. Needless to say, much of our discussion in the podcast was about schools, the challenges that particular sector faces, the impact of air quality on children and teachers, and how projects like SAMI are engaging kids in the science of air quality. We discussed much more, of course, including the value of observatories for indoor air quality. I could genuinely chat away to Henry all day. He's down to earth and practical and, considering how much he's got going on, very generous with his time to talk to me. Thanks for listening. This is Henry Burridge. So, henry, if I ask you to give a report on the state of air quality in schools today, what kind of things would it say at the moment?

Henry: 3:12

I think the first thing it says highly variable. All of our measurements that we've made in schools shows that some particularly classrooms. I think classrooms are a good place to focus because it's where children spend the majority of their days, in the presence of adults as well. It affects staff illness if disease transmission is occurring. So classrooms are often adequately ventilated. But there are a significant proportion of classrooms where the ventilation seems to be quite poor and it's often hard to ascertain why this is the case.

Henry: 4:09

So if you're going into schools and making measurements, particularly these days, teachers are aware of things like opening windows, and they're more likely to do that because they know you're monitoring. We've had a number of studies where we've just put white boxes which are sensors on walls of classrooms, so teachers are much less aware of them. What we see is that even when a classroom, two next door classrooms, are architecturally similar in terms of ventilation provision, we get very different effective ventilation supplied to those classrooms. So I think there's both an engineering architectural issue, but there's also the issues of behaviour. Is it because one person likes their classroom a bit warmer than another person and so they don't open the windows?

Simon: 5:15

I think you said something really interesting at the beginning there as well, and that is that we can't forget that schools are also workplaces. So while we often think of schools in the sense of education, they are actually places of work as well.

Henry: 5:29

Yeah, absolutely. I think in the UK we have something like half a million teaching staff, so it's a really chunky number, and I think that teachers are massively overstretched. They're very time-poor people, they're constantly dealing with unexpected challenges in their classrooms, and so we have to somehow, over the coming years, ingrain, ideally within teacher training right through to continued professional development and an acceptance of the need to manage air quality. Think of it like this if a teacher walked into a classroom and it was pitch black, they would turn the lights on. If the teacher walked into a classroom and the sun was blinding the children's eyes, they would draw the curtains. You know these. We accept that teachers have to manage their environment in terms of light levels to aid children's learning. We know that good air quality supports better learning and we need to, you know, ingrain it into our teaching stuff. They care about kids, they care about education. If they understand that air quality matters for children's learning, then I really believe that the vast majority of teachers will start to take air quality in their classroom quite seriously.

Simon: 7:03

So I think there's obviously a number of things that factor outcomes in schools and classrooms in particular, and one of the things, particularly in the UK, we have to take account of is the age of the stock. So we're dealing typically in most schools in the UK with naturally ventilated classrooms. Is that right?

Henry: 7:32

Oh yeah, I think something like 95% are naturally ventilated.

Simon: 7:37

Do you have any sense of the overall age profile of the school stock? Is the vast majority of it what we would call in the rest of the built environment traditional buildings almost? Is it kind of 60s and 70s back or where does it sit really when we look at typically schools in this country? What are we talking about?

Henry: 8:03

I think the answer is there is no typical school in this country. You're absolutely right. A lot of our schools date back to at least Victorian times in terms of buildings. The government does collect data through what's called the condition data collection surveys, which sort of rolling surveys where surveyors go out to each and every school about 23,000 of them, I think Every few years and record details of the buildings and their condition.

Henry: 8:49

There's a lot of interesting architectural history written about UK schools. I always default to Professor Alan Short on these matters, but I think they would argue that, broadly speaking, architecture of schools has happened in a number of waves and I think the first significant wave that remains in use today would probably be associated with the Victorian type era. And in terms of ventilation and actually light, those buildings are very good for both natural ventilation and natural light, often very good. They often have quite big ceilings, big windows. Of course the problem comes that they're expensive to heat because you know, at least historically, they would have had single pane glazing and you know tall spaces tend to be more expensive to heat because as you warm the air it rises up. So you're putting all this energy to kind of keep people who are sat on the ground, warm and the air you're warming is obviously physically, you know it's going to rise up.

Simon: 10:10

And would it be fair to say that we've seen in a lot of the more modern era schools holding onto natural ventilation when perhaps a lot of the rest of the built environment has moved into more mechanical fields of ventilating their buildings? Is the driver in the UK for that, as it has been elsewhere, to keep infrastructure costs down in schools and I think a propensity to try and keep schools as cheap as possible to maintain and manage natural ventilation was seen as a way of doing that, rather than having expensive, say, evac equipment or mechanical ventilation equipment to run and maintain. Do you think that could be a thing as to why we see so much natural ventilation in the education space?

Henry: 11:01

I think cost is always a factor at schools and it's almost certainly a factor here. If we're talking about new build schools, very often the funding for the building is relatively centrally provided at some level of government, but of course the ongoing running costs they're associated with the school locally, and so there's this balance between what's cheap to build and what's cheap to run. And then I think the other really important factor is we've had a long standing school building stock and very often what we seek to do is add new buildings to existing schools, and that obviously has implications for things like centralized heating, ventilating and cooling systems.

Simon: 12:06

And I don't think the UK would be unusual in that sense when we look globally at education in general, unless you're in very specific environments that require a lot of conditioning of spaces. So in very cold climates or very hot or warm tropical climates, it's very common to see naturally ventilated spaces. I think that's been a common trend everywhere.

Henry: 12:30

Yeah, and I think it's also a common trend that, relative to other building types, in most countries schools are relatively poorly provided for. So even in countries where it is more typical to have centralized HVAC, you know it's a relatively poor provision compared to you know, for example, what might get put in an office space and the maintenance is a big issue in schools, probably more than it is in offices, for example. I suspect it's as bad in other public buildings. Frankly, I think you know we learned a lot about schools during the pandemic. I particularly learned a lot about schools in the pandemic, not just in the UK but elsewhere and you're right, very challenging environments in other countries too. The one building, the one public building spaces that seemed even less well resourced than schools was NHS owned buildings, I would say.

Simon: 14:01

Interesting and not high end centres of excellence, but residential care or community hospitals that you know. We think we've got an aging stock when it comes to schools. You start looking at some of the stock of the health care providers and that is. There's some really old buildings there.

Henry: 14:24

No, you're quite right, and you know residential care, you know care homes. A lot of these are not purpose built buildings, they've been repurposed and that is a massively challenging issue. And, interestingly, that actually ties back to the other end of the spectrum early years care. You know, in the early year settings in the form of nurseries. Again, a proportion of these are attached to schools. They tend to be in purpose built buildings. A massive chunk of them are buildings that have been repurposed and they now hold how's a nursery for early years provision. So that you know it's both ends of the spectrum really.

Simon: 15:18

That's interesting. Yet schools as we typically think of schools, they're probably one of the few parts of the built environment where the vast vast majority of it has been designed for the intention of what it was for, and that is for teaching groups of children for long periods of time, and it's. We've got to be careful not to do down natural ventilation, as you say. There's a spectrum. Some schools perform very well and actually naturally ventilated schools can be designed to achieve very good levels of air quality, can't they?

Henry: 15:53

Oh, absolutely, and you know that goes right back to, you know, our oldest building stock. The Victorian buildings are, you know, typically very easy to ventilate as long as there haven't been, you know, thoughtless retrofits implemented. I think this need to build, you know, cheaply and often more compactly in our inner cities has resulted in a number of schools having quite low ceilings and there is a real challenge there to make sure the occupants are using the ventilation provision. Because these sorts of rooms, unless you're opening windows, you see CO2 levels rising very, very quickly, getting to high levels, and that's a key indicator that the air quality in that classroom is probably inadequate and is highly likely to be affecting the learning of those children. In the same way that if there's a massive noise outside the classroom they're not gonna learn as well, and things like colds and flu and COVID they do spread in these sorts of spaces, particularly when they're not well ventilated.

Simon: 17:31

Well, I think all of us that have got kids can attest to the inevitable colds and flus you get when your kids go back to school. I mean, they're virtual petri dishes, the education sector. And rightly so. I mean that's partly what they're there for is to build up the immune system of our kids. But we all know, we know it's like a ticking clock come midway through September, early October, you know it's coming.

Henry: 17:58

Yeah, and my wife's a teacher and when she trained as a newly qualified teacher they had a name for it which I forget In the first year they expected to get a lot more poorly than they had been historically, and I think it's kind of interesting that we accept that Like. I don't think that's okay. I think you know there is a really interesting question, as you say about, like, if we took away all exposure to disease in early stage life, it would probably have very significant implications for our well-being later in life. But I don't think we're anywhere near that spectrum. I think we're massively overexposed in places like schools and it has implications not just for the pupils but for the teachers as well.

Simon: 18:55

Sure, and I think that comes nicely onto the other, the other things that create outcomes in schools. You know we've talked about the stock and the types of school buildings that we talk about. Form and classroom sizes have a big impact on outcomes. You can have a reasonable ventilation system, but if you've got a lot of people in a small space there's not necessarily a lot you can do about it. You will put a system under pressure. So there is a reality of putting lots of groups of people in a space for long periods of time. It is a very particular type of risk in classrooms that we don't necessarily see anywhere else, do we?

Henry: 19:42

No, I think that's true and scientifically. That's why they're really interesting spaces. You can do lots of modeling and analysis of spaces of classrooms because they're quite a unique space. You get a large number of people, particularly at primary school, where kids tend to be based in one classroom most of the day. They're spending a big chunk of each day, five days a week, in the same classroom with the same people and that's quite unique. Certainly pre-COVID and it's coming back. Open plan offices aren't that dissimilar in that regard. If everyone's going into their desk nine to five every day, that's a relatively similar dynamic. It doesn't seem to be that typical of working pattern at the moment, but we'll just have to see how that evolves, I think.

Simon: 20:46

Yeah, yeah, interesting. And then I suppose it comes onto the kind of risks that we're thinking about in classrooms. Obviously, there's been a very singular focus on infection control over the last couple of years, for good reasons, but that's only a very small part of the picture of the things we're interested in when it comes to classroom health and air quality, isn't it?

Henry: 21:14

Yeah, and the big one last year was energy prices. There was lots of reports of schools getting energy bills that they simply struggled to pay, and so, as we can't go into these issues with a one track mind, we can't be saying to everyone oh you've got to open your windows all of the time. It's not practical, it's not going to produce good learning outcomes, because the children are going to be quite cold at times of the year and it's going to be unaffordable for the schools. So we have to have this balance of energy. We have to realize that we are ventilating for the sake of the well-being of people. It's not about the building, it's about the people, and those people are there to perform a function, and the function isn't to breathe air. The function is, in this case, learning, and we have to make sure that the environment, the air they're breathing, the temperature around them, it's all conducive for the students to be able to breathe air. It's all conducive to as many of them learning as efficiently as possible.

Simon: 22:28

So I suppose, if we break down the risks into a couple of pots, because they require different perspectives perhaps. So I've been having a couple of conversations recently in the podcast with those involved in the development of ASHRAE 241, where we're talking about a need to ventilate schools at a rate that minimizes infection and that may not be the kind of state that you put a school into all of the time, but there may be certain levels of risk where you're determining that actually we do need to sacrifice some other things, like comfort, perhaps, or energy costs, to meet a certain airflow rate to reduce risk. So some of your focus, I think, in your studies have been looking at ventilation rates and infection rates during this infectious period of time. So I'd be interested to get your perspective on that.

Simon: 23:33

Another pot that we can discuss is the general need for background ventilation, the minimization of the buildup of other pollutants of concern that are associated with people just being in a space. And then we have the thorny issue of how we deal with the quality of the air that we bring in from outside into these classrooms, which is another perspective we have to take into account. It's the context of where that school sits, like you mentioned earlier, it's fine if you're a little bit warm and stuffy, but if the option is to open the windows a little bit more onto a busy high street as a school, there are other things you might need to take into consideration. So perhaps if we start a little bit with the pandemic type perspective of ventilation in schools, we saw a lot of advice coming out during the pandemic about the types of things that classrooms could do.

Simon: 24:41

You were monitoring schools during that period of time, weren't you? And you were also involved in, I think, co Trace, which was also looking at infection control in that period of time. What were your takeaways from that, and do you see us perhaps doing similar things to North America with things like ASHRAE, where we do have very particular standards for particular types of risk scenario that we put schools into a state of Well, I think it would be nice to think that, if it would be nice to think that we could change the way schools have ventilated in response to specific events.

Henry: 25:30

It took a massive global pandemic to really get any attention on school ventilation. We were monitoring. We actually got monitors into schools, quite a lot of schools in over the Christmas period, 2020, 2021. And then, of course, the government had a massive lockdown. Some schools actually started back for one day and then most didn't and were locked down before they went back. They reopened in that March and our monitors had been in there the whole time and you could see that they were on out on.

Henry: 26:20

Typically, the advice at the time was very clearly open all your windows and schools took the return to full school return very seriously.

Henry: 26:39

All the schools that I'm, you know, aware of the very diligent risk assessments around COVID transmission, you know lots set up one-way systems and all sorts of things and they took ventilation, you know, appropriately seriously.

Henry: 26:53

Classroom windows were really opened wide, our same monitors. You know that was in March-April time it was actually quite a cold March and April, if people remember and it took until the following November, december to temperature levels to get back to about the same level. And what we saw was that the carbon dioxide levels in the classrooms in November and December were significantly higher than they had been in March and April. And that was in a year where in the March and April the advice from government was very strong Open all your windows, full staff. You know, by September we were getting messages about learn to live with COVID. There was, you know, a sense that you know we were really being told to sort of manage the pandemic quite differently and our data really showed that that came through to ventilation levels in that November and December which have proved to be much more typical of the ventilation levels that we're seeing in schools now.

Simon: 28:15

You know, not often horrendously bad, but there are certainly, you know, significant portion of classrooms which are not well ventilated and I think that's really interesting from the perspective, as you said earlier on, that there's quite a spectrum of outcomes out there and you can have seemingly very similar spaces side by side, even facing the same direction, exposed to the same wind direction, the same corridor outside the classroom, same number of kids With quite big differences in performance of that space, which shows human nature and people's thermal comfort and their understanding of air quality, plays such a significant role in outcomes in air quality of that space.

Simon: 29:04

From my own personal perspective, I was also looking at quite a bit of data certainly not at the scale that you have been, but I think that's a very significant you have been.

Simon: 29:15

But I got a sense from the data that I saw that if a concerted effort was made, nearly all spaces could hold reasonable levels or adequate levels of ventilation in almost any classroom, except perhaps the very highly densely occupied spaces.

Simon: 29:37

The 32 kids in a port-a-cabin type classroom situation where the kind of air changes that you would have needed to keep the CO2 levels anywhere below 1500 parts per million would have been in the double figures just insane amounts of air change. And these teachers had the fire doors open, the windows open, everything they could possibly have open, yet just a sheer number of kids in such a small space, very difficult to maintain any level of decent air quality. But the vast majority of schools, particularly the new ones, that would have been designed correctly with high and low level ventilation in windows and skylights and controls that could open stuff without having to climb up on things to open high level windows, could achieve reasonable levels of ventilation. The challenge, as you say, is we got into the kind of COVID fatigue stage and teachers were like not another winter sitting in my coat and woolly hat. We started to see a slide back to perhaps what we normally see, and that's a perspective you're reflecting on as well, I guess.

Henry: 30:56

Yeah, yeah, absolutely. Whilst you were speaking, you made me think about the fact that, whatever the reason, is this propensity to favor natural ventilations in classrooms. It's kind of led to actually a number of more modern built classrooms Having quite interesting ventilation systems that you don't see so much of elsewhere. You know we get a lot of mixed mode and hybrid installations in classrooms, so there are technical solutions out there that have been deployed successfully in schools.

Simon: 31:43

Absolutely, and I think that's one of the things that ASHRAE 241 has done has moved away from air changes per hour to equivalent air changes in a space, trying to recognize that there are a number of ways now of achieving a required amount of air changes in a space without necessarily having to exchange 100% of the air in order to do that from outside, that you have UV and air cleaners and filters and a whole bunch of hybrid solutions that mix natural ventilation and mechanical ventilation. The point is that they have set an air change rate and a flow rate for those high risk times under 241 that are at least double what has typically gone on in those spaces and you'd find very difficult to do with just natural ventilation alone. You'd have to support it with other measures. But it just goes to show that I think, particularly in naturally ventilated spaces of all types, that we're going to have to start thinking a little bit out of the box, that it isn't just all or nothing opening windows. It's.

Simon: 32:58

There may be solutions that we can incorporate into spaces that support natural ventilation and reduce risk. The challenges from an engineering perspective as you saw in the pandemic, as there was a bit of a rush for something's better than nothing and people were deploying various solutions as anything's better than not doing anything at all. But very difficult to calculate how much risk you're mitigating when you take that approach. It's far better to understand what your goal is first and then providing something that can meet that gap, rather than just seeing what you can afford to buy and putting that in. I guess you were part of that melee as well in the UK at a certain period in the school period where there was just a clamour to do something.

Henry: 33:48

Yeah, and you've got 23,000 schools. I think it's in excess of half a million classrooms. You can't just roll out a one-size-fits-all solution to them. It's impractical, it's nonsensical to suggest you can.

Henry: 34:10

What the government here did do, which I think was a very well-intended, very sensible measure, was accept that most classrooms were naturally ventilated.

Henry: 34:23

That was going to be very hard to change in the time scales needed and what they tried to do is they recognise the value of carbon dioxide monitors as an indicator of indoor air quality and linked to per person ventilation rates.

Henry: 34:47

And the different devolved governments did different things but the sentiment was broadly the same and, for example, in England there has been one carbon dioxide monitor sent to. There's been carbon dioxide monitors enough for one per classroom for every classroom in England, where things never go perfectly in a pandemic, and I think the areas where it was, communication about these monitors was really lacking. Staff were not given guidance on how to use them quickly enough. We did an enormous amount of work to try and fill that gap and really struggled because we're engineers, we're academics and we didn't have the right comms channels to get out to the teachers and we really struggled actually to get through either the government or through the union. So all these things took a long time and I think, whilst it was the right thing to do to deploy these carbon dioxide monitors, doing that alone wasn't enough. It needed a whole package of support around it that was lacking at the time.

Simon: 36:27

Yeah, and I don't think schools are alone in that either. I think there's a lot of good intent to try and raise awareness in the right way and provide tools for people to make the right decisions, and CO2 monitoring was a tool, particularly in schools, that did have value. But it's the translation and the use of that tool is how we frame those solutions and the general understanding of air quality, where this stuff gets difficult to translate it out into the field, which is a great segue, I guess, henry, into your work with Sammy, which is really looking at that third pillar that we need to talk about. We've talked about the buildings and the context and the environment that drives risk, but the third pillar and arguably the most important, particularly when we've got spaces that need to be managed by people, has got to be the people themselves, the citizens' awareness of air quality and how you engage. Do you want to explain a little bit about the Sammy project and the idea behind it and where it's currently at?

Henry: 37:38

Yeah, sure. So Sammy, which is SAMHE it's called the schools air quality monitoring for health and education. And then the schools has an apostrophe after the S, which we had many a debate about, because it's all about involving the schools in monitoring the air quality in their spaces. So we were given two years and we're about a year and a half into the project to try to deploy about 2,000 monitors to schools, and any school anywhere in the UK can apply, still apply to join the Sammy project, and what they get is a monitor, a decent specification smart monitor in the sense that it connects to the school Wi-Fi and that's sent to them for free. And then what's really important is that they get access to, to our web app which we've developed. So the web app is really enormous provision and you kind of think of it in two parts. One side of it is data visualization. So we have a lot of visualizations that are suitable for different age group children throughout the school curriculums to support their understanding of the data that they're seeing, and they can download the data, use it for science projects etc. And then we provide a large number of activities where they can really engage with their air quality in the school via this monitor. So one activity, for example it takes them through doing a load of exercise in a classroom in the presence of the monitor and seeing that the carbon dioxide rises. Then they're asked to leave the classroom and they'll be able to, on another computer, see the carbon dioxide levels coming down, and teachers and pupils can set up their own accounts to see the data in their school.

Henry: 40:29

And, of course, what's really important about air quality is that it doesn't become something we're trying to panic people about. We are giving people new information, information that they didn't know about before, and we very clearly need to communicate what inferences, if any, they can make from the measurements they're seeing. So, for example, there's a lot of information that we can use to communicate things. So, for example, the SAMI monitors one of the metrics they report is TVOC, so Total Volatile Organic Compounds, and everything you've ever smelled is basically a VOC, and so we encourage them to think about, yes, the VOC. As you see in your classroom, they might be harmful if they've got poor quality furniture that's off-gassing, or there's cleaning products being used very recently, but they can also be completely harmless. For example, we get them in an activity to open an orange near the SAMI monitor and they see a spike in the VOCs. It's obvious that orange, if they eat it, is going to do more good for them than any impact on the air quality.

Henry: 41:56

So communication needs to be managed very carefully when you're dealing with air quality, particularly when it's in places of relatively vulnerable people like children, hospitals, particularly patients in hospital. They don't have a choice, they have to be there. So is it helpful to tell them that the air quality in their hospital ward is bad? Arguably not. And then homes is a big challenge. You know an English person's home is their castle and you know they'll be damned if you're gonna. You know Mr Scientist is gonna tell them what to do in their home. So you've really got to motivate things in the right way so we don't see things like you know the COVID fatigue that you referred to. It needs to be an ongoing process. We can't have this as a flash in the pan response. It's something that needs to be ingrained in the way we think about our environments.

Simon: 43:03

And Blimey, you just skirted around the edge of probably a very deep philosophical question around risk tolerance and who has responsibility for risk in an environment and who has to accept it. I think one of the clearly interesting parts of a school environment is that children, our children, don't have control of the risk necessarily that they're exposed to in a classroom in the same way that we would have control over the risk that we would be exposed to in our own homes or even, as an adult, that we might have in our workplaces being able to raise concerns. So if they are, again, it's a very interesting environment. Schools that we've got our children are in places for long periods of time in perhaps their most formative years, both educationally but also physiologically, where they're not in control of a lot of the outcomes that they're exposed to. So it's an important area for us to get right, isn't it?

Henry: 44:12

Absolutely, and I think you know this is something that really sits at the core of the Sami philosophy is that we think that children should be given more agency about the spaces that they're inhabiting. It should be okay to have a conversation with your teacher and say, look, the air quality monitor is a bit high, do you mind if I open the window? You know these can be sensible conversations and I think you know children, young people, they should be involved in those conversations and they should be encouraged to be involved in those conversations.

Simon: 44:50

That's really great. Yeah, what a great point that if we can find ways of engaging with students, like we have done for years with the sustainability agenda and the green agenda kids are brilliant at buying into an idea if it just fundamentally makes sense they can really drive these things in schools, can't they? If you catch them.

Henry: 45:11

Yeah, absolutely so. We've had some really nice experiences around schools setting up air quality clubs and, you know, meeting every week or fortnight and they get, they just get really into it and they get really interested in taking our monitor to different spaces within their buildings and then they, you know, they tell the teachers about it. Oh, mrs M, you know we, we measured Mrs C's classroom before and you know your levels are better than hers and they, they, they really get involved and they increases sort of their positive contribution to the school community and I think if we get conversations like this going, we won't just end up with, you know, physically healthier schools. Schools will be a more, you know, engaging environment where kids are learning not just on arbitrary data that you know someone measured somewhere else. They're learning based on measurements that they've made and that's really important.

Simon: 46:19

Yeah, and what a grounding in science as well. Eh, Because you're you're talking about building physics and engineering and air chemistry, and social science and education and health. I mean it just captures so much air quality when you, when you just switching kids on and making them aware of the importance of the environment that they're in opens up so many avenues for them to get excited about.

Henry: 46:47

Yeah, let's not forget economics, right? I mean, you know why. Why? Why don't they have, you know, lovely shiny new schools? Because the government can't afford them.

Henry: 46:57

You know, and it's this whole conversation about, you've got a limited budget, you've got, you know, you've got an environment that you need to manage and and we increasingly, I think we've we've risked in recent years, at a global scale, on lots of different things, becoming very one dimensional in our thinking.

Henry: 47:17

This is good, this is bad. We need to start thinking that actually, everything is tied together in a very complicated way and we we don't need to to understand and solve everything, but we need to accept the complexity and and and see the connections and not make isolated decisions. You've got to make a decision based on the whole. You know the broad implications of the choices that you're making, and air quality is a great example of that, because it's something that people are, you know, breathing in every second of the day and yet it has links to, you know, coal burning on the other side of the world and climate change, and you know you know the cost of benefit of, of of certain engineering interventions. It has lovely social science and behavioral science. It's a great topic that I think we can engage not just kids, the whole nation.