Alright, so we are going to move on to our last session of the day. We've been talking about this indoor chemistry things and indoors happens to happen inside a space we called buildings. And so we're going to focus on the building this last aspect of this last session today. And our primary speaker here will be Jeff Segal. He is a professor of civil and mineral engineering and a member of the hub advancement of buildings at the University of Toronto. And kind of as an indication of the entered. Yeah, entered to listen to nature of the field. Jeff is the Banneham, Banneham, Tantan bound sharing civil engineering but also has joint appointments and the Dalla Lana School of Public Health and the Department of Physical and Environmental Sciences. I'm a PhD from the University of California Berkeley. And when I first met the ponytail Jeff, 20 years ago at the University of Texas at Austin, he was strongly committed to let's say inserting science into the air cleaning market, which I do all the time now so either Jeff was a trailblazer in this field, or he didn't finish the job very well. But it must be the former, because he, he's a real internationally recognized expert as both a member of the ASHRAE and is the fellows. And as one of his colleagues stated today Jeff is one of the most knowledgeable thoughtful insightful speakers in the field of building science and indoor air quality. Well, he wasn't an author on the nasum report. He wasn't off. Sorry, the nasum report on why endocrine chemistry matters he was an author on the health risks of indoor exposure and find particular matter and practical mitigation solutions and their book is bigger. So it must be better. And they have practical solutions unlike us we just say would not it doesn't matter. So, just research interests include healthy and sustainable buildings filtration air cleaning ventilation control particularly matter and the cognitive impacts of indoor air quality. And going back to Glenn's questions this morning what motivates Glenn, I'm sorry, I have no idea what motivates Glenn. But I have a hint to what might have motivated future research from Jeff and then talking to him. He started to think more and more about the environmental justice issues surrounding indoor air quality so with that, like Jeff, you know, finish this introduction and have him finish off this session. So, thanks very much for the introduction. And, you know, obviously there's been some great presentations and panels already this morning and I will comment that, you know, I wish I could have come up with a clever title, but Madonna's building science phase is not very well known so there it is. So I want to start with an example that is very simple compared to much of the chemistry that's been discussed today and the chemistry that's discussed in the report. And this is some recent data we've collected and what you see here are two plots of the performance of two different air cleaners and not very good one on the left and a better one on the right. These are in five different environments measured over a two week period. And so you see on the X axis there is the effectiveness or how much those those air cleaners are reducing the concentration of PM 2.5 in the space. And there is one conclusion from this that has come out and in several talks today that I think is really important the environment really matters. You see a very different performance of the very same air cleaners when they're used in different environments. I don't think that will surprise people very much other than it kind of starts to build the case here for the complexity and the differences of different environments. But there's something else that I think is equally important in these plots and that's the width of some of these distributions. And again this is over relatively short time scale two weeks in each of these environments, and you see a huge distribution of the effectiveness in many of these environments. So the very same air cleaner in the very same environment can perform very differently at different times. And I think that tells us a lot of what we need to be thinking about for indoor chemistry. So fundamentally indoor chemistry is driven by the context and the context because it's indoors is partially shaped by the building. And so if you can kind of go through all the major parts of the report. The building is going to influence things. So what I want to do today is talk about some examples of how the building influences things and what I think that means for some of the recommendations in the report. So if we kind of think about this idea of, you know, this is chemistry indoors, at least for this presentation, this is about the indoors where chemistry happens. And so kind of briefly an overview I'm going to talk about some important things in buildings I call them systems but I guess some of them are some of them aren't but but and how they're important indoor chemistry and how we can characterize or measure them. And that's a big theme of what I'm going to talk about today. And then what does that mean in terms of the recommendations from the report. So fundamentally, I believe to to if you want to understand or manage indoor chemistry you need to understand the building. And the three systems I'm going to talk about today are ventilation surfaces and HVAC systems. And I want to make the comment right at the start that there's in fact lots of other systems, especially the people in those buildings and some of the other things that go on in buildings that are really important to but I have the time I have and so these are the three I've chosen to focus on. So I think everyone has a basic concept in their mind about ventilation ventilation is the replacement of indoor air with outdoor air. And usually we kind of divide it into two bins the mechanical ventilation bin. That means it's driven by a fan. And there's lots of different kinds of mechanical ventilation you could be exhausting like from a kitchen range hood or a bathroom or you could be supplying with a ventilation system. You could have a balance system that both exhaust and supplies, you can integrate it with the heating ventilating and air conditioning system. That's what the V and HVAC is. And of course, it can be controlled or scheduled by the operation of the building and often is. So that's mechanical ventilation and then there's a term that we use a lot of different words to describe it. I'm going to call it leakage and all it is is air that comes from the outside in or the other way around. That's not driven by a fan. And this can be intentional. You can open a window to get natural ventilation. Or it could just be leakage through the building enclosure where and it's going to be driven all leakage is driven by some sort of pressure difference caused by commonly things like wind. The inside outside temperature difference or what people like me call the stack effect or pressures that are induced by the the HVAC system and drive some of those ventilation flows. The comment that's made in the report and is kind of important to say is that from an indoor chemistry perspective, ventilation is going to increase the concentration of things that originate outdoors. And it's going to decrease the concentration of things that originate indoors. But I think really important for for chemistry processes and many people have made this this this point in the literature is that the time scale for ventilation is really what's important. And particularly when ventilation is relatively low, we have the opportunity for a lot of chemistry to happen that might not happen at times when the ventilation is higher. One of the earliest long term measurements of ventilation rate that I know of was done by Lance Wallace and colleagues and in rest in Virginia and his home and rest in Virginia, not too far from here. They did measurements over the course of a year with SF6 successive SF6 decays. So this is like kind of the cause of climate change here. And the point I want to make is the is the dynamic nature of it so over the course of the year almost 5000 measurements of the air exchange rate you can see certainly a central tendency somewhere on the order of, you know, 0.4 or so air changes per hour, but you see again this distribution there are times when it's much higher and times when it's relatively low. And I think that that is is really a really important point, and one that that you know it might be driven by for example the inside outside temperature difference. The wind at this particular site tended to be higher in the early afternoon. That drives some of the variation, of course things like windows open also drove some of the variation here. This variation occurs, and it shows up in more modern work as well I think we've seen some other data from this house today this is a house in in California this is work done by Lou with Alan Goldstein and Bill Nazaroff. And what they did is they measured the flows not only between the inside and the outside but between different parts of this of this home, and two points I want to make one is that, you know it's dynamic they did measurements at different times and you see different flows at different times. But the other thing is that in this particular building there is a fairly consistent pattern of flow that a lot of the indoor air comes from the crawl space, and a lot of the indoor air goes to the attic. And so if we think about some of the things that have been discussed today, if you're interested in what might be influencing some of the concentrations of compounds in this house, it might be related to chemistry that occurs in a crawl space, which is I think very different from a lot of the indoor spaces we tend to think about. And if you're interested in the impact of the indoor compounds have on outdoor air, they might be moderated by things that go on in the attic, which is another space we don't usually think about as an indoor space but can be important. And I'm going to return back to addicts a little bit later today. So the problem with the or a challenge with the those two results that I just showed you was that they're quite intensive. Take a lot of resources and so on and now we have low cost sensors and so is there easier ways to kind of get at the dynamics of ventilation rate. There's some work by Korea who is a Brazilian researcher who used indoor and outdoor carbon dioxide measurements and a signal processing approach to assess the air exchange rate shown over a week in his apartment. You can see that over very short time scales the shaded periods are nighttime, the light periods are daytime, but you see over very short time periods, these this variation in the in the air change rate quite large variations factors of three or four over relatively short time scales. And so it kind of gets to the importance of if you're studying something with indoor chemistry, you really have to think about these dynamics. And others have taken this further this is some work that the Massey a la vie did where took the same approach and applied it to a year of data from from my house in Toronto. And you can see that again, over the course of a year, you see this very wide variation in in air change rate, and you can start to understand why measuring the exchange rate at one moment in time can can can lead to misleading results. This type of approach signal processing is dependent fundamentally on on making a decision about what signal and what's noise. And that's kind of an art more than a science. And so, more recently bow and do did some work where looking if we could use machine learning techniques to take a trace from a low cost sensor. In this case of CO2 but you can do it for for anything you have a measurement of and use that machine learning approach to find periods of decay and analyze those for the air change rate. And if you apply it to the same data set from my house, that same CO2 data set, you can see that the decay rate over the course of the year shows very similar to what I've shown you before, that there's a lot of variation over time, including some, you know, quite higher exchange rates presumably times when windows are open. So, my bigger picture point here is that, you know, this does happen and it is measurable and it is measurable with relatively straightforward techniques and low cost sensors. So, you know, ventilation is is is important for for indoor chemistry in a number of ways. And I think that's worth saying, but ventilation is also really dynamic and has multiple pathways when it when it happens so you need to be thinking about what ventilation you're measuring and how you're measuring it. And also, we need to this came up a little bit in the discussion after Delphine's talk we really need to think about some of the processes that can happen to compounds and air well ventilation is occurring. An example of that is this paper by Zawadol from Brent Stevens group that looked at the what happens to NOx when it goes from the outside to the inside, and presumably the other way as well. And you can see that something like NO penetrates more or less completely from the outside to the inside, but NO2 is lost as it goes from the outside to the inside. And I have to start thinking it's not just the amount of air and the amount of contaminant in that air. It's what might be happening in terms of transformation. I said ventilation summary, but I want to get a little bit more advanced on ventilation because there's another piece of ventilation that even in the building science community we don't talk about enough, but is enormously important. Another movement kind of within and between zones is rooms in a space is really, really important. And so this is some work that Doug Collins did. When he was in John Abbott's group doing a Hono perturbation experiment in the kitchen. And basically what you see is a lot of the chemistry involving Hono is happening certainly in the kitchen. And also in the rest of the house. And so all of a sudden we have to start thinking about about this idea of interzonal flows. I showed this picture here from a older paper but it was done in the same house that that home chem was done in, and the home chem house is interesting for a lot of reasons but one of the reasons it's really interesting is it's the only time I've ever had done or seen any building in a building where the wind direction is so consistent from one direction. Generally you see a huge variation and that affects the distribution of contaminants and the air flows within the space. And the last point I want to make is that as we think a lot about some of the equity issues and think about the kinds of spaces that people actually live in buildings, we will be talking about multifamily buildings and multifamily buildings. There's a certain amount of shared air between different units and multifamily buildings. This plot is from a review paper by Carl Lusinski and Mary Ann Tushy, where they showed things like based on a review of the literature that building construction type, there's certainly a lot of variation but affects how much air is shared between between apartments and from an indoor chemistry perspective. When you do have attached dwellings or attached spaces of any kind, you're going to see some of the impact of chemistry, both in terms of of of reactants and and products that that that go between units. There's a kind of level of ventilation we should be thinking about. I'm going to say the least in this presentation about surfaces, not because surfaces are not important but because there's lots of people in this room who can talk about surfaces. A lot more cogently and completely than I can, but I do want to say some things about surfaces from kind of a building science perspective. And obviously we've heard and the report makes clear just how important surfaces are to indoor chemistry and that indoor spaces have a lot of surface area. There is this this other thing that surfaces have a underlying substrate underneath them sometimes a very complex substrate. But then they also have a film or a layer or a coding that that that changes over time and is quite dynamic, depending on what its constituents are. And the prior history of a surface which we almost never know in real buildings is very, very important potentially to what chemistry that surface might might might might that surface might play a role in. And the one point that I think is so important about surfaces is most of the surfaces in a building are not seen. Most of the surfaces in a building are things that that we don't think about. So certainly there are things like carpet, like in the top image that obviously has a much bigger surface area than its projected surface area, even kind of a low pile carpet. So the bottom figure is from chin at all in in Elliott Gall's group and shows the reaction and the products that are produced by ozone reaction with various insulation materials. And you can see that there is the insulation material. There is the bulk and a lot of insulation materials react a lot with ozone, and that also they're producing a different fingerprint of byproducts. So again a phenomenal amount of surface area associated with with with materials, some of which we see directly. Others less so. There's also what what I call interstitial spaces things like addicts drop ceiling spaces crawl spaces spaces and walls. And those both have a lot of surface area but they also have a lot of potential for relatively interesting chemistry. So the picture on the top is in fact the only picture I've ever seen of something that happens in almost every building in North America, almost every day. And that is the underside of the roof deck produces condensation. That's because it's cold overnight the roof deck gets cold, warm, moist air from inside condenses on that in the early morning. So if water is important to the chemistry, and you've got air either coming from the attic to the building or going from the building to the attic, or both, as is often the case, you're going to see some interesting chemistry. Buildings like the one we're in have, you know, just these phenomenal number of spaces that we never think about they're above above drop ceilings or in in mechanical areas or other things that that can have a lot of surface area and can be important to chemistry that we probably don't really think about. And then the, the last surface unseen surface that's kind of near and dear to me is the HVAC surface and HVAC systems just have phenomenal surface areas associated with the ducks themselves as well as heat exchangers filters, but really we have these surfaces where both there's this concentration of high surface area, and often dirty conditions and, and sometimes extreme temperatures humidity is other things. So, from the perspective of building science, if you have a process where surfaces are important, I think that this community very much understands chemical characterization of surfaces, but also consider physical and and biological characterization in the mix and in particular I always like to talk about the role of water and particularly adsorbed water on surfaces. Don't show any recognition if you don't want to reveal your age, but if you think about popcorn ceilings which had their popularity. A popcorn ceiling is a very prime site for growing mold and a lot of buildings, and it's probably a very important site for chemistry as well, because you have each of those little valleys has a little collection of adsorbed water. And so again there are these surfaces and indoors that we probably don't give a lot of thought to that are, you know, no one's taken the time but are likely important to to indoor chemistry. The last system I want to talk about our heating ventilation and air conditioning systems. They do a lot of different things in buildings they're often when people talk about them are accompanied by schematics like the one you see here where you have. You can bring in outside air with ventilation you can heat and cool the air you move the air with fans. Especially in North America we're kind of more used to this type of model which is common certainly in most residences and and most older residences, where you have no outdoor air the building gets its ventilation from leakage. So you have a recirculating system, but this idea of a basic HVAC system is usually accompanied by this type of thought process where you know the HVAC system is carefully designed to provide comfort, maintain indoor air quality it's it's it's installed by trained professionals and it's operated in energy efficient manner. That's wrong. I want to be clear I'm not. I'm actually I'm only a little bit knocking the HVAC industry here this is more reflecting societal values. But really, this is probably a better description of HVAC systems. You know they're designed using rule of thumb. They're definitely designed for the time of construction of the building, very often installed by the least cost bitter, especially if you spend time in schools, but a lot of buildings they're minimally maintained. And they often have significant control or failure so from an indoor chemistry perspective, we're not that interested in the ideal system we're interested in the actual system. And we've known that the HVAC systems can be important for indoor chemistry for a long time. This is a review paper from close to 30 years ago that that that shows the many different ways that the HVAC systems can contribute to indoor air quality issues and a lot of indoor chemistry potential there. Here's some work from Glenn's time as a PhD student looking at ozone reactions on on ducks and duck components. And so, so these systems can be very important for indoor chemistry. So if we think about how do we characterize an HVAC system from the perspective we might care about an indoor chemistry. One of the things we care about is the recirculation, how many building volumes pass through the system. So the graph that's on the screen is from three different studies and three different parts of North America all homes. So you see this recirculation rate, how much air goes through the system when it's operating ranges from a couple of home volumes per hour to about eight home volumes per hour. So there's this huge variation in systems in HVAC systems, and you can measure this flow, even in relatively complex systems, usually using something like an orifice flow plate, or some some type of velocity measurement that is rectifiable and is important to do given given the variation you see. And this is important for indoor chemistry because it's another time scale that might be important for indoor chemistry. It also is going to show how much connection there is between the HVAC system and the rest of the building. You might have some type of air cleaner that I said removal here but could also be a source of things that you might care about from from an indoor chemistry perspective, how much it's going to contribute to mixing and a variety of other issues. And I'll come back to this point a little bit later but you know HVAC systems are also a site of extreme conditions. You have very hot temperatures near near heating heat exchangers, you have liquid water in almost all cooling systems, and you have insanely large amounts of illumination near UV lamps and that was discussed earlier today. For systems that provide mechanical ventilation, another thing that's really important is how much of the air they're providing is outdoor air. And this is a surprisingly dynamic number the data here from a study we did in big box retail stores, and you know, five different stores and they all have very different amounts of outside air coming in, and it doesn't really have a strong correlation to how much air they're moving as well. We measure this doing a carbon dioxide split or a variety of other ways, but it turns out to be quite important to be able to assess how much outdoor air is actually being provided by a mechanical ventilation system and I just want to highlight that this is really dynamic too. Most buildings modulate the amount of outdoor air that's coming in, depending on things like occupancy or, or a user schedule or something like that. Not only that most HVAC systems do not operate continuously, they cycle on and off to meet conditioning ventilation or other loads. So these are data from about 7000 homes monthly averages for the runtime and and the outdoor temperature. I showed these data a lot, and there are two points that are worth making. How often an HVAC system runs is very variable, you see some systems that run almost all the time some that run very little. The average number and these data come from all over US and Canada is that that faint red dashed line there at about 18%. And so this shows that if you're not measuring runtime, you could, you could be in a scenario where the HVAC system matters a lot or it matters very little. It's very important to measure lots of different ways of measuring runtime out there, including more even that are on this list. And it should be something that's kind of part of the indoor chemistry toolkit given how important it can be. And, you know, kind of everything that might happen with indoor chemistry is tied to the runtime. Barb already showed this plot. And I want to talk more about it because because this is such an interesting finding. And, you know, this shows the the the cycling of the air conditioner and the removal. At least during periods when the air conditioner is operating of some of these organic assets. And there are two points I want to make about this. The first is that, you know, you can predict this we did a relatively simple model of this led by Heather Schwartz and our bond. And, you know, using a very simple Henry's law kind of approach, we could model with, you know, a factor of two or so accuracy. And then we had this these these removal rates. And, you know, so one thing is you can predict this and so it's important to know when the coil is wet and when the fan is running and that sort of thing. Another point I want to make about this is that if you look at the magnitude of the removal rate which is shown on the y axis on the lower part here, those are pretty big removal rates, certainly larger often than ventilation so this could be a really important process and one that I think needs more attention. The other thing I want to say about these data that that I think is so important is kind of gets to some of the interdisciplinary aspects of this, and I had a slide about this and I took it out because I thought it went too much in the weeds but I'm going to go into it anyway. The, the, how we operate a cooling system is really important to how long that water stays on the coil. And so one of the things that's happened as we care a lot more about electricity use and energy efficiency is we make coils that have the fins for heat exchange that are closer together. To do that water drains more slowly off the coil. And so, if this chemistry is is important for a compound that you're interested in a more energy efficient air conditioner is going to have more time for that chemistry to occur because the water is there for longer. The other thing that's interesting that we found out kind of by accident and I still can't believe this is the case, but when you operate an air conditioner the standard practice used to be that you would, when the thermostat conditions were met you'd shut off the compressor and the fan, partially to allow the water to drain. Now, a lot of systems these days again in the nature of energy efficiency, keep the fan running after you shut the compressor off. What that means is that all the water that is sitting on that coil and sitting there for longer because the coil takes longer to the drain evaporates back into the air. And so if there is chemistry that I mean I don't know that there's certainly a probably aqueous chemistry going on, but then are those compounds coming back into the air when that water evaporates. And so again it kind of maybe gets into the weeds a little bit but kind of highlights the importance of thinking about things like is the coil wet. So, getting to the end here. If we get to the recommendations in the report, you know, indoor chemistry matters. If you look at the 15 recommendations, 11 of them explicitly include researchers. And the common I would make to researchers is characterizing the building is often needed to understand the chemistry. If you characterize the building you can often generalize chemistry results to other buildings that have some of those same features in common. And then another thing that that I would comment down is this idea of extreme environments, James Scott, who's a mycologist and a colleague in public health has this great quote from a wired magazine article a while ago that points out that few places on earth get as hot as a rooftop or an attic, and few places on earth get as dry as the corner of a heated living room. And so really we're in the world of extremes I would add UV to that list as well. And so I think there's an opportunity for very interesting chemistry that probably occurs in indoor environments and nowhere else. There's several or three of the recommendations that address funders and funding agencies, and I have two messages here one is, you know, I understand that you're predominantly interested in funding fundamental chemistry research, but I would say that building characterization should be a part of that to allow for the extension of that of that chemistry research. We're not talking big dollars here most of the stuff I talked about today was done with low cost sensors or, or, or could be analyzed based on data that was being collected anyway. There is a couple of the recommendations that address kind of building design standards, and a couple that address the importance of interdisciplinary collaborations, and just want to make the observation here that the impact that indoor chemistry will have on other fields will come from about common language and about the contributions that that other fields make and I'm continually struck by the fact that building it operators and those who actually maintain buildings are often not at the table when we're discussing some of this chemistry that is is is very important and so I think there are several populations like that that should be included. And I want to finish here by by making a global point which is made in the report and I think it really needs to be to be echoed. What this is is filters that were collected in for a week in social housing apartments in Toronto, nine apartments in the same building, and the one with green tape is blank. You know, you don't need to be an indoor chemist or an indoor air quality expert to understand that there is different things in the air in these environments. And I think that a big part of convincing the world that indoor chemistry matters comes from being able to visualize it and make it clear. What's going on why the chemistry is important, and how do we kind of visualize that so that people can can can respond to it. So I'll finish there. Thank you. We have time for maybe one or two questions. Thank you, Jeff fascinating talk. What one question I had was that you talked a lot about how the dynamics of exchange between different rooms between, you know, indoors and outdoors. And something that is also very important is the is the mixing that occurs within a particular room. And I was wondering whether, you know what what research has been done on on that question and the factors that affect sort of the rates and the degree of mixing that happened within a particular space. Yeah, I mean, mixing is enormously important. I want to like, that's a great question. And it's actually surprising. There is lots of research that has kind of characterized mixing in different spaces but we don't have a lot of fundamental research on mixing. And I think it is so important and the easiest thing to do in an indoor chemistry experiment is, you know, to deploy some low cost spends sensors around the space to characterize some of the mixing. And I myself do a, like I can't look at a room and predict the mixing. In fact, I was sitting here earlier today and trying to understand the where the supply and the return vents were and trying to understand mixing but like one of the classrooms I teach commonly. It's only after we did some measurements in the room did we realize that the two supply registers were on either side of the return register. So all of the air supplied by the HVAC system just kind of went out and back in, and then then go in the rest of the room. So, characterizing mixing is enormously important. And it is often competitive with ventilation in terms of dilution away from a point in a space. Okay, since you ran a little bit long I think we will stop there. And because I lost rest rock paper scissors to Charlie and Glenn I am leading this last panel, either that or they're picking on me because I'm the youngest, I'm not sure which.  And we will talk a little bit more about building sciences as we finish up this great workshop. And as they are getting sitting down I'd like to point out it's kind of excited that this other than that guy from Toronto, everybody here is a public federal or state organization so we have some governmental opinions hopefully throughout the day. So I want to start off just everybody introduce yourself you get 21 seconds, just who you are where you're from and what your major interests are 21 seconds go. My name is Brian Gilligan I'm a deputy director of the Office of federal high performance green buildings that GSA mechanical engineer by background but a recovering bureaucrat by my major area of focus right now. Interested in green building policy and promoting high performance green buildings. I am a researcher Philly at CU Boulder and I also work at the Colorado Department of Public Health and environment. Any views or opinions I have today or mine alone and out of the agency. And I'm an environmental engineer so I'm really interested in taking a lot of the building science we have here today and distilling it into actionable guidance. Hello, I'm Dave Rouson I'm the director of the indoor environments division at the US Environmental Protection Agency, and I think the principal interests I bring are around both promoting and sometimes conducting research to advance the foundational projects around what happens indoors to promote in the end public health, and then the other side of that is putting in place programs and and communications and policies to to equip both the buildings community, the health community and the general public to take effective action to reduce risks. We'll skip you Jeff. Yeah, I'll see my 21 seconds. Hi, I'm Brett Singer. I am at Lawrence Berkeley National Laboratory where I've been for quite a long time now 26 years. My interest. I'm an environmental engineer by training and my interest is in how fundamental processes physical chemical processes that lead to exposure. lead to people being exposed to chemicals play out in real buildings so I'm really interested in a lot of the subjects that Jeff brought up and we're talking about today. Okay. I actually want to start with you Brett. If you sent me a sentence this morning that got me thinking, and I just want to try to give us a little background of what you meant by it and basically sent me. This quote says one person's indoor chemical trash is another person's life experience treasure. And I thought that was an interesting perspective to put some of this in context so could you explain what you meant by that. Sure. I took a fresh look at the report yesterday on the airplane I said let me just go back to the introduction and, and one of the things that struck me is it dove right into hazards chemical hazards. And, and, and this is something that Jeff and I both deal with as energy efficiency people right where people who do building energy efficiency, think that buildings were built to like consume energy, but they're not they're built to protect people from the outside world and ride spaces for us to live and do things and have fun and, and the chemicals that are in those building and the chemical processes are the result of all the materials that we build into the building or us to enjoy the buildings, the products we use. So we do these things we have these exposures as a result of an attempt to like, you said better living through chemistry right. And that says the first point is that we should not lose sight of that context right we talk we talk about some exposure. You know it's herping exposure or something a lot of people like that smell. So they're like intentionally bringing that into their house, and gaining benefit from it so when we talk about some hazard or risk. It should be in that context that remember that like these are not things that people, you know, it's like a life without risk is a very boring life right so people are doing things because they want to have experiences number one number We said that the changes and there's a lot of focus of over changes that have happened over the past decade or two decades. My friend over here, Charlie Wester wrote a great paper about changes in indoor chemicals whatever since the 1950s. Right. And I think that that longer perspective is really important right so yes there have been a lot of changes over the past two decades or so but, but a lot of first of all, that's not the first two decades that are into a chemical environment have changed they've been changing since we've had indoor indoor environments. Number two, a lot of those changes are because we were trying to develop better products we're trying to develop surfaces that are easier to clean or that would become moldy less frequently or you know there were some benefit better filters etc. That being said, variability is huge right so there's a lot of talk about variability and I want to bring up a couple points so it's not just the wonderful work showing variability within the same home how much variability there is from room to room, even two rooms within the same home. Terrific. Over time we see variability in the chemical environment within the same space just over the season, over one day, different you do different things in that space and you start going to different spaces of variability, even within the same space, spatially right you should. It's a great picture of the engineering building right even within space, pretty simple space not a lot of surface but just even within that space. If you look at one part of that space you're going to see a very different chemical environment than another part of that space. So, there's tremendous complexity tremendous variability. And it's it's constantly changing that said I'm going to I'm going to stop I have some more comments to your questions but I just for the introduction. Like, oh my gosh it's so complex and it's always changing whatever else, but I think that there are general generalizable lessons that we can take or there's, there's general processes or general. There are common conditions right so Jeff shows nice data residences, especially within the US, you know vary a lot less than residences differ from, let's say, classrooms or offices. Okay, so there are sort of generalizable things you do about certain types of spaces number one number two. While the materials are always changing. Okay, and the environment change of the year. There are patterns every year we know something about that we know something about the range and temperature humidity conditions we know something about the variations in HVAC something about the variations and ventilation and then the materials and the products that we have while they are changing. So the chemistry that's going to happen in indoor spaces over the next decade or so is already set by the environments that are built today. And by the products that we use today. Okay, so it's not an impossible task to learn some things that will be useful to us over over a time scale that by the time we learn them we can actually use them. Only a minute and a half after you said I'm going to stop there. So, the next one I go to go to Jeff and Odessa and the question is, you know, we, we, we all are tasked with measure, seeking to make some measurements in the indoor space, what we're called in general IQ measurements. And in those measurements we have different objectives we have how the building operates the chemistry. And then of course the health outcomes. What really matters and how should we focus that limited funds we have when we make IQ measurements. I think to add on to the what measurements that are out there I think the access now to lower cost sensors is really important. And I think more importantly it's the training of those who look at the data on what they're looking at is really important so taking the time to make sure that our facility managers understand what they're looking at and what actions to take next specific next steps on how to handle issues that they might come across. So, I think, in working with schools and deploying particle monitors and other CO2 VOC sensors out there. That's been a big pushback from schools is what do we do with this data how do we act on it so I think the more that we can think about how we're these commonalities that we're discussing that we can package those up and start to think about actionable items that are really important. And then also there's been a big push to over the pandemic for portable air cleaners and I know a lot to say about that being deployed in classrooms. We've seen a lot of schools, not quite have that understanding of how to appropriately fit them but now I think we're ourselves, what does it mean to appropriately fit a space with portable air cleaners in order to reduce the particular load so I think it's important to introduce the monitoring with the control technology and have those play together on that aspect. Yeah, I don't have much that I don't have much to add to that other than to say, I think that the training pieces so important because I think a lot of people in this room look at a low cost sensor and understand that there's a huge uncertainty associated with that output but I don't think that's well understood by most people who are using low cost sensors so teaching people about actions to take and using low cost sensors to evaluate those actions right like oh, my CO2 is much higher than it usually is in the classroom I can open the windows and does it go down. And I think that that that's the specific type of training that we would get a lot of benefit at from low cost sensors. So Brian, you run organization that's in charge of, say 1500 buildings about. So when you're going to do IQ measurement, what do you what what's your objective of those three the building the chemistry or the health. Well, I've, first of all, I'd like to echo the sentiment that just providing data without clear direction is actually counterproductive. We have found a lot of. In the past we have deployed sensors and buildings and given our building managers a lot of data, and it's just one more thing that the building manager is now responsible for considering. If they don't know what action to take it, then become something that they're never going to look at again and don't trust that method. We have generally used sensors and monitors in building automation. Mostly what we're looking at our thermal comfort. I know we have a very extensive smart buildings program, GSA link that right now is is going through a process of trying to understand how to do a better job of evaluating thermal comfort and and kind of corrective actions that can be taken. What we would like to do is start to expand that a little bit to other parameters carbon dioxide and particulates I think are the ones that we're most interested in. To see if there are specific actions, especially if we can tie it to our automated fault detection systems to say, oh, we have some sort of a spark is that relating to poor air quality. And if so, what actions to can we take or recommend to the building manager to correct that. And does it actually yield better air quality for time. So I'd say that's really our focus right now. I think on the subject of, you know, deploying sensor technology to help in this area. I think one of the things that I know our organization EPA is trying to pay attention to is that they're fundamental operational approaches to buildings that need to be calibrated to the kind of building and the kind of use it is that are important to undertake as principal means for trying to minimize exposures and contaminants in a building and that the focus on measuring can sometimes detract from the attention to those basic engineering kinds of controls. I think that where our sense is that where we're going with availability of lower cost sense sensor technology. Recognizing some of the limitations of the technology is to be able to provide clues to what might be going on and what actions are important to implement. To help reduce exposures and concentrations. And the work I think we're doing is we have developed guidance over the last few years about how to think about what kinds of sensors to deploy and how to interpret data for that and we're moving towards trying to produce guidance about metrics and how to get certain kinds of numbers, how to think about those numbers what clues they provide and what actions you might take to, to improve the space. So. Okay, go ahead. This is the question about large scale measurements. Yeah, we're still in measurements. Great. So what we talked about here was about general air quality, which is important. I want to bring it back to the chemistry specific element and, and Professor Scherpin mentioned something earlier that I thought was really wise and she said, we should have more field studies that are designed by And there's a lot of wisdom in that comment as Glenn pointed out. And what we can do I think sometimes when we're trying to understand how common processes are or distributions of exposures, for example, distributions of impacts. We need distributional data on the factors that go into those impacts. So, Jeff showed some great slides of here's how much runtime we see in HVAC systems. And then he raised this point at the end of How much water is left on the coil and whether that fan stays on is actually a very important parameter for certain chemistry that's happening. And we know almost nothing about how that plays out distributionally we have some idea of when changes were happened to the equipment. But, but actually how that plays out in real buildings and these things that these pieces of equipment get installed. So a couple of simple measurements where you're just measuring literally like the fan operation and the humidity downstream of this, you know, the supplier humidity could give you that information. Right. And getting that from, I don't know a thousand homes or something in different places of different different system vintages knowing the system vintage some of the technology would be immensely powerful for trying to understand these distributional impacts. Good points. We'll move on to the next question. The next big picture here is, we've mentioned many times today we have millions of different spaces in the US and Canada that have millions of different sources and sinks and HVAC systems and all these different indoor spaces that range widely and on their chemistry and their impacts. From your perspective, let's start with you, Brian. What indoor spaces do we need to focus our research on considering we can't do everything and what kind of different data do we need about those spaces that that we don't have now? Well, my, my experience and my focus is mostly in office buildings and there I think is a lot of benefits looking at other spaces. One of the things that we found in a research project we did called well built for well being was that there's a lot of difference in the environments and different types of spaces within office buildings and that smaller higher occupancy spaces tend to be much more dynamic than an open office, for instance, where we could measure all day and not really see much variation in the things that we were measuring carbon dioxide particulates, TBOCs, but we saw a lot in these smaller spaces. So I think understanding kind of what's going on in those small dynamic spaces is really important. I think we need a mix of indoor environmental quality variables. I don't know as much about chemistry, so I haven't really talked about that, but I was really impressed with Crystal's discussion earlier. And kind of there might be some very simple measures we can take to get a better handle on that and we can definitely do that with our with our federal community. I think we need to also be looking at certain outcome measures that maybe are things that we can get in a large organization. I'm thinking of things like sick leave aggregated at a building level that may be something that we can we can go out and get simple new kind of the newest version of sick building syndrome surveys I think they're called wellness surveys might be something we should be deploying and trying to compare that to different operational parameters. And at GSA and our smart buildings program, we collect a tremendous amount of operational data. So I think trying to measure and bring those those data streams together should be a real priority going forward. Jeff. Yeah, I have two answers to the question the first one is building on what Barb and then Brett said I think that modeling is one way of identifying when indoor chemistry is important and that's an obvious place to target target measurement resources. The other answer is I think more broadly within indoor air quality but certainly within indoor chemistry to, we have a means of addressing kind of some of the systematic disparities that that exist where some types of buildings and some populations experience disproportionate negative effects from indoor chemistry and this is also an opportunity to to look about look at indoor chemistry from that lens, not only where is an important but but who is it important to say a lot of times those two overlap. So they happen to be the most sensitive populations that happen to be in the most, you know, the older buildings and infrastructures with the less or the least amount of ventilation involved. And to that end to I think making sure that we've talked a lot about indoor outdoor characterization and how they play off of each other I think making sure that when we do things like in schools looking at indoor air pollution measurements that we're considering the outdoors I think a lot of times that when schools implement indoor monitors they only put them indoors and they're not really thinking about outdoors and we don't have enough necessarily in all locations, especially in rural locations outdoor enough outdoor monitor data to kind of co locate so I think that's another important aspect as well but yeah one other thing I was going to say to I think an important part in thinking about. The school side of things is adding to that human activity survey of what teachers are doing and what students are doing in that classroom, because we can do everything possible to make that place well ventilated and you know have all these controls in place but at the end of the day. If the students are spray painting by the air intake. You know that's something we can't. Education and a training component, not just to the building managers not just to the administrators, but we really need to be working with teachers and students as well on the importance of that I think that would take a big role in improving your body as well. I'd like to pick up where you left off a desk and just talking about schools, a little bit where I sit, sort of trying to implement and drive policy and policy change. I'm always fascinated at how often I run into what seems like common sense from a policy perspective isn't what drives change and big change it's it's often some landmark thing some and it's like a pandemic and how that can affect how people think about things or some important development in the science that is the buzz in the in the community and the and so when I when I think about schools. First of all on sort of the baseline EPA is doing a lot and our and our programs are designed to influence what happens design and construction phase what happens by facility managers what teachers do what administrators do what the community does what how kids should you know how to help kids do the right schools to improve indoor air, but there's this other thing about the massive investment that's needed particularly in school infrastructure in disadvantaged communities and what goes on with chemicals and chemistry in buildings, I think is one of those places that contribute to our understanding of how much we need to improve the infrastructure and the operations within schools, particularly in disadvantaged communities. And so the translating the first investing and research around indoor chemistry in school buildings, and then translating that effectively into the findings and what the implications of that are. And I think that one of the things that's very underestimated in the US and other places is the enormous economic and productivity impacts that for indoor air in schools has on kids for a lifetime. And, and what the silent packs of that are. And so sort of the socio economic research on this, I think is very important to. Okay, I was a good transition. We have in the US roughly 60 million people going to school every day. And we have, we have data that small studies, you know, 10 to 50 classrooms that show increased performance in classrooms with better ventilation increased a decreased illness absences and things like that. So, indicating that we should get very good benefits from from improving ventilation and schools. We live in Montgomery County here in Maryland and we just install not we sorry the school district just installed 10,000 indoor air quality monitors and monitors, among other things co2. And one of the things that we did have my colleague do was look at some of the one day co2 measurements and compare that with past school performance. Those historical data should indicate that there should be a good trend there, but it's really just comes out as a snap as a shotgun. And so, starting with you and so what are the challenges to really implement these large scale interdisciplinary field campaigns that can actually show these health effects that are, you know, that are limiting our ability to give and actually say this is what you need to do with that data so what are what are the, how do we turn these big massive data set into something that Brian can, and David can go out and say, this is what you should do. So, that's a big discussion today is like, are the low cost sensors necessarily picking up the components that might be impacting those scores one, maybe it's not air quality necessarily driven it's a complex ecosystem education spaces so thinking through all of these other factors of, you know, where is it located what are the other impacts involved in performance outcomes so that's a, that's a tricky one. I would also say, there was more discussion to about more carefully characterizing the buildings that we're looking at so if we're looking at bulk amounts of data is that representing necessarily the building characteristics that we need to be concerned about in different types of spaces in different regions, and how those spaces are being used so that's a tough one. I would also say, keep going back to the training because it's so important. How are people engaging with that space in a way that makes sense to to effectively manage that building and I think that's something we really need to understand more of like what are those barriers for making those decisions based off of the research that we're doing here are findings. So actually taking our findings and giving the guidance and then that guidance actually being put into practice but to answer your question on the low cost sensor I think we need to do more on co locating more instrumentation around it and saying can we make those larger conclusions based off of just what those those measurements are coming out with. Yeah I was just going to say that I think that one of the things we need to do to contextualize that data is talk to the people who maintain and operate that building as well are those buildings and what we see for example, in, in other contexts for example long term homes in Ontario that a very good predictor of COVID death rates during the pandemic was was there the absence of an on site maintenance person at a long term care home. And so I think that there are often data like those that really help us understand the context for the chemistry that we're are relatively easy to collect, but we don't. To that point to that exact point a lot of facility managers and a lot of schools where multiple hats. So they just may not even be aware of what's an appropriate filter is it fitting correctly is it can our system handle something better. Do we even have filters like what what does this look like so I think that that is a huge part of the conversation. Well, falls into the next question, and this is how do we create the connection between the health outcomes and the chemistry the health outcomes to give proper guidance to both building occupants and building managers to affect change in the indoor environment. Brian. Extremely important question and I think from from GSA's standpoint the way we regulate how our buildings are are designed and operated is through our facility standards. Something we call the P 100 in order to change that we need to have a specific relevant. Recommendation or standard that we want to follow tied to a health benefit that's been clearly articulated that is also relevant to the diversity of facilities we have and the different constraints we have. And it makes me what we were just talking about I think is is really relevant to this idea that the GSA require requests from Congress a certain amount of funding each year for maintenance and we routinely get about 70% or less of what we request. And over time we've amassed a 4.6 billion dollar backlog and deferred maintenance. And so any kind of change that we suggest making has to compete with that backlog. For resources and anytime we suggest something that is a cost issue. It raises resistance is one less dollar that we have to spend on what we already know we have to focus our own on. Making recommendations that are cognizant of those cost impacts and concerns is really, really important. And then again a clear connection to the benefit because we spend money hopefully to create environments that are are helpful and productive to our to our employees. But we have to show that there's that connection. Dave, do you have other thoughts about what you need to make guidance because that's a lot what your division does from the indoor space. Yeah, I just want to reflect a sort of interesting dynamic being here in this panel. And Dustin, we talked a little bit about this when we were getting ready for today about how much of the benefit would be for me hearing about what other things, other things are said here and being influenced by that. And the programs I carry out versus how much I might contribute to influencing things just sitting here on this panel listening to discussion today. I'm feeling like the major benefit is some of the perspectives I'm hearing and learning but what within that. We are, we I think, through our non regulatory voluntary programs at EPA have contributed to advancing beneficial practices to improve indoor air in buildings. Some of that the dynamics around our programs I think are appropriately non regulatory and voluntary in nature, particularly what happens in homes and the way people live in homes and I was thinking about Brett's comments earlier about, you know, sort of paying it. It sort of pointed me towards the idea of we're trying to help with unintended unnecessary risks that people don't want to take and we don't understand or they might not have anticipated them. But there are, there are environments the kinds that Brian's responsible for and and in schools where I think there are some requirements that should be in place and that kind of policy change requires the continued research and science that that people in this room and and others are undertaking. The, I think the other reflection I have on on guidance here I already spoke to that I think there's some basic practices to improve indoor environments that are around appropriate and adequate ventilation effective and efficient air cleaning and source control, but then understanding what's happening in a particular building through improved understanding of indoor chemistry I think can help influence our guidance beyond beyond that. I think the one other comment I'd make in this area is that there's sort of, you know, primary reduction of chemicals through a sort of a primary exposure that I think is where most of our guidance has been. And this, the indoor chemistry is leading to a better understanding of kind of second order exposures to chemicals and particulates that I anticipate is going to affect, you know, particularly what we say about understanding your particular building your particular space and the right things to do there. Yeah, quick question. And I think it's for David, perhaps for Brian. What are targets and are this EPA in the indoor environment you don't have regulatory authority over the indoor at least in the home. But are there target concentrations for example you have the outdoor, you know, where you want to you have targets, I think are required. But are there ones that you would consider healthy environment and for, you know, certain levels CO CO to formaldehyde that can give us specific air so whatever engineering controls you use. You know, this is a recommended level that you should clean to Brian I think he said you or me so go ahead. I'll briefly comment. We are, I think with the emergency, the emergence of low cost sensors have been doing a lot more thinking and work over the last couple of years, moving towards guidance that is grounded in some quantitative targets. And I think our plan is that in the coming near term, EPA is going to start saying more about quantitative metrics and what those could indicate in buildings. We, we've had some conversations across the federal government over the last few years about about that and there's probably not going to be single action levels. But if you see numbers, like in this range, that could indicate this kind of thing. And here's the way you should think about that, what other, and what actions you should look to deploy to help with that. So using them as indicators. And, but the only place that EPA has in my program is at a non regulatory quantitative target is for radon, but the sensor technology I think is getting to the point where we're looking at PM find particulates. Co. I do as an indicator of what may be happening overall and indoor environments for maldehyde and others and and I anticipate that will move more into that being a supplemental piece of information, in addition to doing the right things on adequate course control, their filtration air cleaning, another way to pay attention to and understand what kinds of interventions are needed will be will have guidance around around that. And I would just very briefly say that most of the targets that commercial office buildings are subject to our industrial hygiene based rate on carbon monoxide things like that. If we're looking at a measurement, it's mostly comfort based. So try to stay below 1200 parts per million CO2 because you start noticing smells and people get headaches and things like that. We don't really have a set of targets for concentrations of CO2 particulates, etc. inside buildings. And that's something we'd like to start looking at, at least as a key performance indicator that are health based. Exactly. Yes. I want to wrap this up, but I want to wrap it up with one last question. So it's okay. Charlie and if I finish, I just want one as we're the last panel. And if we're thinking, you know, what impacts we're going to make in the next five years. I think it calls this meeting again in 2030, and we're all up here in 2030. And you give me a 30 second answer each of what you think our successes will be as far as improving the indoor quality in all the buildings that we have. And Brett, you're quick on your feet. So I'm going to start with you. The question is, what do we think the successes will be five years from now in terms of how our knowledge of indoor chemical processes, indoor chemistry. Just improving the indoor environment and you're not limited to indoor chemistry with our knowledge in their chemistry improves the indoor environment. Yes. Terrific. I think that whenever we're talking about generic guidance, we have to think of the public health model where it has to be very simple. So the best we can do is come up with simple. Here's something you should be really careful about. Here's something you should, you know, be careful about if you're, if you have a sensitive health condition and here's something that you're not. I think that we will, I don't know all of what those things are yet. But I think that we're going to have a much better understanding of the benefits of German side of UV and where that can be applied. I think we're going to be able to cross, I think we'll be able to cross off the chemistry concerns actually for that one. I think also on the chemical air cleaning, I think that there's some technologies that actually do have promise that will gain some understanding about when they're useful or not. Jeff. So it's not clear me if this question is what I think we will be talking about or what I hope will be what you hope. Yeah, okay. So if it's what I hope we're talking about, I hope that indoor chemistry is kind of part of the conversation. And by that, I mean that, you know, that that that a funding agency, for example, will consider indoor chemistry, not as some weird thing, but in the, in the context of, of, of, you know, what they do day to day and and a topic like any other. Thank you. Um, So overall, I'm thinking about both our agency and it's public health mission and and overall some of where I hope we are. And I think I'd like to first build on what Brett said that that we've answered some questions about some of the technologies that we can deploy indoors to either refine or add to the tools that we can use to improve indoor environments, both through, you know, large funding streams that are in place as well as helping all parts of society in their residential settings. The other thing I think from, from my perspective is that we're able to provide Brett sorry to plagiarize you again. We're able to translate some of what we're learning in the research community into simple straightforward guidance and steps that can produce public health benefits in general and impact the health productivity, livelihood lifestyle of people where they are and where they spend time indoors. Thank you. Um, I guess what I'm thinking about the low cost sensor part in figuring out as we learn more and more about what we can do with that data is translating it into a way that you just get automated messages that are so easy to follow direct to action go do this and your air will be so I think, you know, much like looking at decreases in CO2, we can now understand maybe more about our ventilation rates with just using low cost sensors I mean that being able to not have to do these extensive big studies would be great. Right. Yeah, I guess I'm hopeful that in the next five years will have more direction about what we can measure an individual spaces that can use this feedback to modulate our building operations in real time. And if there are proxy measurements that kind of tell us something about what's going on with indoor chemistry that would be really really helpful. Right now, it's much more. How much air are we putting into space as opposed to what's actually going on in that space. And with that, I would like to thank the panels and since most of us are federal employees. Again, these are our opinions of our panel members, not their respective agencies. So that's our disclaimer for everybody. And so I'd like to thank the panel and we will have one last little speech by Glenn to wrap this up and thank everybody for attending. Hello everybody. There's been a lot that we've experienced here today. I'm going to focus these comments on a few things that the three of us discussed on a call last week just to kind of some wrap up ideas and comments and thoughts but I also made a bunch of notes on here while I was sitting listening and so that if it sounds a little disjointed, you know, that's why or it's just me. But we want to make the point that over the last seven years, the Sloan Foundation supported a tremendous amount of indoor chemistry research. And this funding resulted in over 300 publication was publications with many more to come and really advanced our understanding of what's going on, plenty of discoveries, and just all kinds of hypothesis generation going on. From fundamental surface chemistry to full scale field investigations, molecular modeling to full scale building chemistry modeling. This covered the gamut basically all aspects of indoor chemistry you can imagine, but they're clearly, and you can see that from this conversation we've been having today there are gaps in our ability to go forward. And in part, because we are focusing, you know, on this fairly narrow subject of indoor chemistry which is appropriate for the program that's what we wanted to do. But we would like to see this broaden and marry this, all of the folks that we've been discussing here, it's been brought up many times, you know, but I'll come to that in just a minute but the marrying the built environment with the chemistry and exposure and health. And all those things together. And even know this understanding of what's happening indoors with what's happening outdoors with the. Yeah. But the Sloan program is over, and it's leaving a pretty big void at least in the chemistry part of this equation. So the question we are posing ourselves, of course, many of us is it possible to maintain this funding level, or better and broaden its scope. In one area that's really made a difference was when Dr Azuzki Paul Azuzki very cleverly said I'm going to put some really good instruments in the hands of very clever people who are very productive. And it made a huge difference in the analytical component of this process. It's more of that probably should be done to advance this field that really replace instrumentation, get more instrumentation into the hands of young eager scientists that want to advance this field. And you can see the piece of it. And you can see that here in, you know, for example, Delphine's confinezation mass spectrometer or Dr politics, high resolution mass spec you know these are things that need to be in there in order for us to understand these spaces, even if we're deploying low cost sensors and such at the same time to understand other aspects of that space. The workshop should make it clear that we need well defined studies that test the relationships between indoor environments, chemistry and measurable health outcomes. We really do need to do this in a cross cutting way. But the health impacts of indoor exposure often kind of difficult to study. In part because the individual measures of exposure are challenging. Dr Paul has shown us one way to do that in a very effective way. It can be costly and invasive. And there may be, for example, they are still more costly than the traditional sort of epidemiological approach to looking at outdoor air pollution where we have a ton of data from health records and things that aren't as difficult to collect on an individual basis. So we need to bring together experts chemists building scientists engineers models epidemiologists toxicologists and others medical doctors to design such studies, and we need to do that because even if we can take this information that we collect from these spaces relate them to health outcomes. And so by itself in that silo isn't enough to create anything actionable. I think we've heard the word actionable many times today, and we need the to understand the sources, the mechanisms, the activities of occupants to help the building operates all those things in order to make recommendations and guidance and reduce disparities. So, I won't go on more about this. You guys have heard much about this. And we won't find the solution here and now about how we expand this funding scope, but we can continue the conversation. In service of this goal. The question is broadly for everybody here but also more specifically for the folks that are that work for federal agencies. Would you benefit from a similar type of workshop that's focused on indoor air quality research that's put together on a more frequent basis maybe in a more targeted way, quarterly by annually. So would you like to see participate in these activities, and how can we leverage such meetings to create fundable collaborations. I'm open to any thoughts you have on that. Elaine. So, so this has been fascinating workshop and heard a lot of good things on this last panel. So, made me think about the whole convergence research paradigm that NSF is, you know, currently promoting. But it's been talked about broadly and I know like there's, there was a yes and T article talking about convergence research and how that model could work and I see. I see indoor chemistry is really ripe like where you are right now as being something where that would work so having a set of workshops with kind of that and like in mind that you'd be that that would be going toward designing, you know, this next cross cutting and, and trans, well, transdisciplinary but convergent study would would be really, really fascinating and so I guess the whole point of convergence research to issues. You include right up front at the table, these, these, you know, people that represent building, you know, maintenance operators, you know, building operators building designers, teachers, you know what whatever it is that we're we're hearing are the stakeholders that should be there so that you know we kind of get more resolution on the sorts of comments that we just heard. You know, so now you know what you need to have at the end come out, but also how those people can be engaged in the actual design and conduct and, and, you know, have those you know when you say you can't get into schools to do studies. If they're, you know, the school operators are at the table from the beginning. You know how what would that look like. So I guess I guess the point there is just maybe learning a little bit more about that convergence model and I had learned about it through this. You know, the NSF nanotech infrastructure, but to your point about the, how expensive these really critical, you know, laboratory equipment are, and needing that infrastructure. Now, and going forward to really can, you know, really advance this, this field, which again is going to be more and more and more important as we're working toward climate adaptation. So just making, making these connections and seeing where other groups of scientists have been successful and thinking about that would, I think would be really beneficial. Vicki, did you want to mention something about that nanotech. You had mentioned this to me as well, this convergence research. Did you have any comments. Yeah, I mean, you made an excellent point. Thank you for bringing that up, but also even the new directorate within the National Science Foundation is really looking for partnerships with communities. As well as researchers, the tip directorate is a place that this type of research might really resonate with. And social scientists are really important to engage as well. I'm on the advisory committee for the National Science Foundation environmental research and engineering. I'm going to push as a committee member, you know, thinking about this issue that we're talking about now within that committee and see if they can are interested in picking it up as an issue like where do we go to further this research. I think not have so many ideas right now. I might just stay up here. Sorry. You know, I really liked a lot of the talks today and I'm just going to Delphine in particular, but everybody did a nice job and what I liked about Delphine's talk was she talked about this. The VOCs as being sort of a pot of chemistry, if you will. And then we talk about low cost sensors. And so maybe just by looking at VOCs and just trying to reduce it. What did you call it? You said it, what was it? It was a combustible fuel. It was the fuel. So let's let's decrease the fuel. So that would just mean lowering all VOCs and then that would lower the ones that you're measuring in your laboratory at Yale University with that wonderful method that you've developed. So I think that the conversation has to continue. And in this way of how to really think through the barriers to continuing the research to make buildings more healthy. So kids can think more clearly in school. I don't like the fact that these whole environmental justice issues are also part of all of this. We have people who are disadvantaged and then we're putting them in a school to make them more disadvantaged. I don't see how as a country that's a good plan for us moving forward. I also think there's economic, you know, people discuss this today. So incentives potentially of how to make the indoor air and indoor climate better for everybody. Anyway, you brought up some really good points. So thank you, Glenn, for letting me talk a little bit. We'll have one more comment and then we'll have to wrap up. Yeah, thank you. I wanted to continue on what was said earlier about what I'd like to see in the future. So I have an academic background like PhD, but now I'm in the industry. We're part of the company that deployed the sensor in Montgomery County. And what I see, you know, every day is that we talk to schools, right, we talk to customers, and they don't really know much about indoor equality. And I come here and I learn so much. And I feel like I came here by chance. Someone mentioned it and I'm like, okay, I'll go, I miss, you know, research. So I came here. And I feel like this, like a lack of connection between the industry and the people on the, you know, talk to school, whatever, and then the research world. And, you know, if there's, you know, a chance for having more industry and more, you know, teachers and building operators, I think that would be amazing because, you know, at the end of the day needs to come together. So, and by the way, I'm going to ask some of you for your slides if possible, because I want to be able to show it to, you know, small customers. Thank you so much. We're glad that you came by chance. So I'm going to wrap it up for us, since we're running a little over on behalf of the authors of the National Academy of Sciences and Engineering and Medicine report. Our supporters here at NAS. Yes. Oh, you're up here. If you're interested in a hard copy of the report, please email Darlene row. She's in the back and we will ship you the R copy. Okay. I want to make sure I couldn't remember exactly everything. So, and on behalf of our of the writers of the reports, the support our scores here at NAS our speakers, our panelists, my colleagues, Justin and Charlie. We thank you for your participation and hope to see you again soon.