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ASHRAE Journal Podcast Episode 2

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Left, Mike Gallagher; Greg Nilsson

What You Don’t Know Can Kill You

Last year as wildfires raged in California, some building owners closed outdoor intakes but left bathroom intakes open, pulling smoke into their buildings. In this episode of ASHRAE Journal Podcast, Greg Nilsson and Mike Gallagher, P.E., Fellow ASHRAE, discuss ASHRAE’s proposed guideline on protecting building occupants from smoke during wildfire and prescribed burn events and offer some tips for engineers, facility managers and owners.

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  • Show Notes

    In this episode Mike and Greg discuss their personal histories dealing with smoke events before diving into the new planning framework from ASHRAE Guideline Project Committee 44P, Protecting Building Occupants from Smoke During Wildfire and Prescribed Burn Events (2:05).

    They talk about the importance of the framework as it establishes the significance of planning for these prescribed smoke events or wildfires (8:40) instead of waiting until the event is happening to purchase air filters and other tools.

    Greg and Mike dive into the framework, including air filters, such as MERV 13 (14:30), outside air intake (19:20), lite building pressurization (19:00) and economizers (20:55). They also discuss how to deal with smoke-induced odor (11:50) and the health implications of these smoke events (11:55). Going deeper into the health implications, Greg discusses PM2.5 (12:20).


  • Guest Bios

    Mike Gallagher, P.E., Fellow ASHRAE, has been an HVAC systems professional since the days when everything was calculated by hand. His greatest strength is the ability to communicate technical issues in plain, jargon-less English. Mike has worked in four different metro areas with different climates and design requirements, and has designed, sold, installed, retrofitted and serviced virtually every type of air conditioning system used in the U.S. Mike has taught (literally) hundreds of classes in HVAC technical topics. His specialty areas over the years have included built-up DX systems, central plant analysis, thermal storage, control of HVAC systems, practical energy analysis, system problem diagnosis, mechanical system retrofits and maintenance programs to optimize total operating costs. He really enjoys his career, field and the people with whom he is privileged to work. He considers himself fortunate to be able to get out of the office frequently to look at buildings and interact with people. For the past 15 years, Mike has written a monthly technical column for the ASHRAE Southern California chapter newsletter, the Sol Air.  

    Greg Nilsson is a lead technical officer and project manager for the Indoor Air Quality group of the Construction Research Center at the National Research Council of Canada, located in Ottawa, Ontario, Canada. Greg’s primary research interests are protecting indoor air quality during wildfire smoke events, along with developing methods and strategies for the evaluation of technologies performance to improve IAQ. Greg is the current vice-chair of ASHRAE GPC 44, chair of CSA No 22.2 187 and has participated on several committees CSA, ISO and AHAM. Greg’s expertise is in the area of measuring airborne contaminants, experimental and equipment design. His educational background is in chemistry, occupational health and safety and industrial hygiene.

  • Transcription

    ASHRAE Journal:

    ASHRAE Journal presents.

    Mike Gallagher:

    You used to have what you classically considered to be fire season, I'm not sure those definitions apply anymore. And I get into these big conversations with people because here I'm this old guy who's saying that I think really honestly, legitimately the greatest threat we face is global warming and people, there's still a lot of people who think that, that's overblown. But the fact that we don't have a fire season anymore, is this about as clear an example of that as I can come up with.

    ASHRAE Journal:
    Episode 2: Mike Gallagher and Greg Nilsson discuss indoor air quality during wildfire smoke events and ASHRAE’s proposed Guideline 44, Protecting Building Occupants from Smoke During Wildfire and Prescribed Burn Events.

    Mike Gallagher, P.E., Fellow ASHRAE, is president of Western Allied Corporation and is based in La Habra Heights, California.

    Greg Nilsson is a lead technical officer and project manager for the Indoor Air Quality group of the Construction Research Center at the National Research Center of Canada in Ottawa, Ontario, Canada.

    Mike Gallagher:

    Hi. I'm Mike Gallagher. I speak with a west coast U.S. accent, and I've lived in LA for the last half of my life, and prior to that was a corporate gypsy all over the country. Grew up in the Pacific Northwest.

    Greg Nilsson:

    And I'm Greg Nilsson. I'm not sure what accent I speak with, but I'm from Canada, so. I currently reside in Ottawa, Ontario, but I grew up in Western Canada. But according to Mike, I have the Eastern Canadian accent, so you'll just have to bear with me.

    Mike Gallagher:

    So I was interested in the wildfire guideline that ASHRAE was putting together, which of course had a preliminary due to all the issues we had last summer that we were asked to do. And we suspended the actual guideline per se, and put out some preliminary guidance, which ended up with the title of planning framework for protecting commercial building occupants from smoke during wildfire events. Now that's a mouthful. I was interested in it because I've been in smoke events my entire life. When I was a little kid in the 60s and 70s, I was in a little bitty farm town outside of Spokane that considered itself to be the Kentucky Bluegrass capital of the world. That was the major crop we grew. After harvest all the fields got burned, and we would go through roughly a two week period while all the fields in the surrounding area were burned.

    Mike Gallagher:

    Where wildfire smoke or, well, it wasn't wildfire right, it was a planned burn, but that smoke was just as thick as what was experienced throughout most of the west in the wildfire areas last summer. And to give you an idea, just if you haven't lived through something like that, fields are burned during the day. And so you're in full daylight, but of course, streetlights are usually on photo sensors and they have been forever. And so the streetlights would automatically come on because it was so dark due to the smoke and a hundred yards away you couldn't see the street light. And if you can't see... Back in the sixties, it wasn't the halogen lights were used to, but still if you couldn't see one of those street lights, a hundred yards, that gives you a pretty good idea.

    And then when Mount St Helens blew in 1980, that was just before I left, and at the peak of the ash fall, we couldn't quite see halogen streetlights at a hundred yards, and I would say that it was roughly the same. So maybe that gives you some context for thinking of what that is like. We would go through that over about a two week period and the fields would be burned when the wind was down and it wasn't raining. So it was somewhat weather dependent and you would typically get three or four or maybe five days of good burns in, and then the weather would shift and you'd have to wait a few days and then they'd finish up. That's about what we went through last summer in Southern California. I've lived in the greater LA area now for a little over half of my life. I'm in my sixties.

    And the smoke intensity in a lot of the suburban communities that were up against the mountains was every bit as much as what I grew up with. And I was getting questions last year about this. And we'd already started the guideline, GPC 44, which is the guideline committee, actually started business last June, July, and had been in planning stages for about a year before that. But then of course, last summer happened and the American West was just covered, and I assume big chunks of Canada as well, although Greg will talk about that, with smoke. And I was getting these questions and coincidentally, we had just started this wildfire preparation guideline, what do you do about the smoke events?

    And so that was I guess, a little bit of serendipity in terms of the timing. What do we do? How do we define resiliency? Maybe we'll get back to that in this conversation. And it's a multidisciplinary thing right, because air conditioning is a piece of this, but it's far from the only way to plan and carry out some kind of a course of action that you've set up.

    Greg Nilsson:

    Yeah. And actually, I appreciate the story. I grew up in Western Canada, we had different burn practices back then and going through university, I spent time with the family on construction sites and we have one year—don't quote me on exactly the year—it was early 2000s. And it was smoke covered, just a light haze. You could certainly see for it wasn't quite as thick as your experience, but it lasted for about two months. And we were out in the hot, pounding nails, working, lifting, and it was not a great experience at all. By the end of the day, your throat is dry. You feel like you've been a piece of smoked meat and it's just draining, more so than the heat is just that constant smell. And it was late 2018 that in my professional career, I came across this topic again, and it actually came up organically out of a discussion.

    There was, I think most people are aware of the fires that Northern Alberta experienced in 2017, the Fort McMurray fires. One of the most costly events for natural disasters, outside of the pandemic, of course, for Canada, because it interrupted the oil field and it devastated the city of Fort McMurray. And there were some, lots of news stories around it. And one of them was talking about a family that had a young mother with her two twins that were being transported during this event from Fort McMurray to Edmonton for emergency care. And one of my colleagues from Health Canada just asked a simple question: what the hospitals do when it's really smoky out. And as a researcher, as someone who is really interested in protecting indoor air quality. I thought, geez, I wonder what they do?

    So we started searching into this and we start finding some information and like yourself, you start going like jeez, you know what, there's information out there, but it's not widely known. And it's a little bit sporadic and there do seem to be some knowledge gaps and exactly how do you address this? So of course we focused our efforts more on critical infrastructure, such as protecting indoor air quality in hospitals. If you think like a wildfire smoke like I experienced, or what BC experienced 2018 or what you guys experienced last year in California, which did impact BC, Vancouver island. So certainly that smoke lasts for a long time and you want to be able to go somewhere to be out of the smoke. And if you're impacted by it, you want to be able to go to an emergency room and feel that, "Hey, the air quality there is better and I can get my emergency care."

    So yeah, it's a really interesting topic. And then we got involved with the, I got involved with the ASHRAE GPC 44, and it is great. The timing is, how did you put it? Serendipitous, because we've experienced a number of these events over the last few years, 2017, 2018 for Canada, and then again, 2020. These events are happening more and more often, and people are asking questions and it is time to get something like what we did going.

    Mike Gallagher:

    I think this is in ASHRAE's wheelhouse. The guidance portion fits well with how we approach things. I think the primary thrust of GPC 44 and of the interim guidance that we came out with that planning framework is planning. A lot of people don't think about what they'll have to do when the event takes place. I'll just give you a couple of examples. When the air gets filled with smoke, you cannot go down and buy more air filters because they've sold out. You can't assess what to do about your equipment, because it's too late. The planning aspect of the framework and of the guideline is oriented toward, what would a facilities person need to consider well in advance? And probably there needs to be involvement with an HVAC professional or even professionals, depending upon how complex a situation they have, they might need a consultant.

    They might need a controls contractor. They might just need their air conditioning service provider. But a facilities person probably is not going to be doing it on their own. And, as you know, the hardest thing to understand is what is it that I don't know. You can plan around things you know, it's the things that don't know that bite you. And so a big part of the guideline is to discuss that and to discuss corollary things like, how do I have to budget? If I'm going to need extra filters, if I'm going to need whatever else, what money do I have to put in the budget? And also, what do I need for storage space? Because if I'm going to buy all these filters, those things are air, right? They take up tons of space, and so if I'm going to have those, how many sets of filters do I need? What do I do?

    I've enjoyed this because I am an engineer who's worked on the service side of our industry for most of my career. And Greg comes from the scientist side and the committee is pretty well balanced between the two. And so I've been learning from Greg and others about what does this mean health-wise, because frankly I was kind of ignorant.

    Greg Nilsson:

    Well, yeah. Sometimes it's what you don't know could kill you. In this case I think the questions around the filter and what you need to do, and the planning framework, that can't be overstated because when you're in the middle of an event, in some cases you don't even know where to go to ask the questions, you just know you have problems. So we both talked about experiencing the smoke and that, and so what does that actually mean? And a lot of the conversations I had with facility operators, in a lot of cases facility operators are driven by complaints by those that are in the occupied space. And those complaints could be, "It smells bad. It's too hot. It's too cold. I don't like this person because they're too close to me."

    There's such a wide range of experiences in the workplace, and the facility operator, I think that they have to evaluate these complaints and try to decide what is the course of action? What can I do, what should I do? And in an event like if you just have a structural fire or something that's close by, it's a transitory event. It's very—it happens, it's done. But if you have an event like last year, it's very fresh in a lot of people's mind that smoke persisted for weeks. And in 2018, the same kind of experience through BC, it was up to 60 days of constant smoke, so what is that? So there's odor, which drives our comfort could impact your productivity, but then there is some health impact here and let's talk about that.

    Because again, within the framework, we tried to focus on what we can do. So smoke is this, here's my scientific term for the day, mishmash of chemicals, gases, and particles. And each one of those can have a health impact and for some people, that impact may be greater than others, but the most data around what can actually impact health is around PM 2.5. Certainly we're seeing it now becoming a factor in a lot of indoor air quality and outdoor air quality conversations. In public communications we talked about PM 2.5. So the goal of the framework is to actually focus on reducing PM 2.5. It's measurable. There's a wide variety of different sensors, which I'll get into a little bit later, that can be installed. So you can check what, how well your implementation is.

    The problem is, is that you can't smell it. And at that link between it smells bad, I don't like it, it smells like smoke. My office smells like smoke or whatever your location, versus the concentration PM 2.5, those may or may not correlate. And I think that these are some of the challenges that we're currently working through in the committee for the greater guideline is we have the framework and we're working on the guideline and we're currently sorting out some of those details exactly how else to address some of these softer factors. So right now we are focused on PM 2.5, and it's a weird contaminant because it's not like ozone or formaldehyde or one of these other ones, it's based on particle size and that's important because in case for those that may not be aware, those particles get into the deepest part of your lungs and have the biggest chance of causing tissue damage on some pretty important tissues. So again, yeah, that's why we're focusing on the PM 2.5 concentration throughout the process.

    Mike Gallagher:

    So, process. I always love how Canadians pronounce that.

    Greg Nilsson:

    You and your accents.

    Mike Gallagher:

    Yeah. Yeah. I just love it. So you mentioned PM 2.5, that might be a good place to start. Coincidentally, there's a lot of similarities between COVID planning and wildfire planning, and the particle size issue is one of those overlaps. There's been significant research study and so forth over the past year and a half or so about particle size infiltration and the generally excepted MERV rating for a filter to be optimally effective at getting most of the PM 2.5 without going any further than you have to, is MERV 13. The next one, not quite as good, but pretty good, certainly better than what most people have is MERV 11. Now, if you do a casual reading, you'd think okay, well, MERV 13 must be what I want then, but there are a lot of provisos that go with using MERV 13 and these are things you have to assess in your planning.

    Direct drive, smaller air conditioning equipment is often not designed to take much of a pressure resistance, static pressure kind of a resistance on the air filter. Now MERV 11, MERV 13, even the MERV 8s, which are probably the most common commercial filter to this point all of them have very similar pressure drops when they're clean the question is how quickly do they get dirty? How quickly does the pressure build to an unacceptable level? And as you would expect, the better the filter, the more effective the filter is, the quicker it gets dirty because it catches more junk, right? So the MERV 13 filter, while it might be fine when it's clean with even though most light duty air conditioning equipment, can get dirty so quickly. That unless you're just sitting on top of the thing, changing filters, how often does it need to?

    Well, at a peak smoke event, daily might not be enough because if the filter gets plugged, then all kinds of damage can take place to the air conditioning unit. And probably in your planning framework, you want to consider what can I do that's the best possible thing that won't destroy my equipment. That's the sort of thing that you need to get someone knowledgeable in the equipment and can it handle a MERV 13 dirty pressure drop. And part of that planning is also what's your commitment to staying on top of it, putting a air pressure gauge or something in place so that you can monitor how much resistance has built up on that dirty filter and then change it when it needs it. And remember, you can't go buy the filters when the time comes, so you have to do some ballpark, guesstimate of how many sets of filters am I going to need?

    So if I have light duty equipment where I'm going to have to change the filters frequently, it might simply mean I can't use MERV 13, I might have to go to MERV 11. And I can tell you from experience that a MERV 11 filter does not plug up as quickly and can go a little longer. And so with that in mind, that might be part of your thought process in your planning. When I estimate maintenance, my default, lick my thumb, stick it up in the air number is, two air filters for every five ton unit. So that helps because a carton of filters, of course, the size of the carton varies a little bit, depending upon the size of the filters. And if you have more than two air conditioning units on your site, you will have more than one filter size. So you're going to have extra cartons simply because they're not all the same size.

    But a typical size carton might be like two feet by two feet by two feet, a two foot cube. And if you figure two per every five ton unit, you could do some quick math. You can figure out how many boxes of these things do I need to have and where am I going to put them? Another issue that Greg mentioned the mishmash style of that scientific term. The mishmash of stuff in that air, sometimes carbon filters make sense. The difference with a carbon impregnated filter is that it's whatever efficiency the filter is, but then they've impregnated carbon in the pleats and the carbon absorbs a lot of volatile organic compounds, VOCs. But when do you want to use that? It's really effective after the fire, when you're trying to do the many different remediation efforts that you might go into to get rid of the smell, or to at least let it drop down over time.

    But do you want to use it during? Well, maybe, I don't know. They will store because every one of filters is going to be inside of a little plastic baggie, and so you can store them, you can keep them, but how many sets? This is all part of the planning and discussion process. And then the last thing I haven't mentioned is the outside air filtration, because typically an air conditioning unit will have some kind of an outside air intake. We used to call that fresh air a long time ago, but in the era of pollution and certainly in the era of smoke events, we call that outside air. And so that outside air intake might need additional filtration of some description. So what can be done? Does it make sense in advance to put filter racks on your outside air and then you only use those during a smoke event? Again, part of the planning process?

    Greg Nilsson:

    Yeah, actually, I'm going to hop on that. One of the strategies that we're promoting is the idea of a light building pressurization. I mean, that operating process may not work for all seasons, but in the smoke season, we're typically in the cooling season, which can add thermal comfort issues that the types of responses that I've heard anecdotally and direct measure is anywhere from reducing the outdoor air flow, which can have some interesting impacts on the system, reducing the cooling ability, reducing—how did you put? Your makeup air, your fresh air, your outdoor air into the space. And if you have dedicated exhaust systems, say for your bathroom or for other systems related to your work, you can end up in a situation where the building could go slightly negative to the outside.

    And I'm not talking about stock effect, because that's a whole another little fun, little factor in this equation. But if your building can go negative, you're going to end up with a situation where you're actually pulling the outdoor air, which in this case is very smoky into the building, which is now impacting your indoor air quality. So within the framework we were talking about, again, so some of the simple factors is just maintenance, making sure that your existing equipment is operating the way it's supposed to be. Is it set up? Can you do the filtration? And what kind of instruments do you have in place to be able to monitor this? You've talked about your filters, so can you monitor the pressure drop across the filter? Do you know how much your system, or when that outdoor or that makeup air flow is going to drop? And do you know if it drops to a certain point, how's that going to impact your building pressurization?

    Are you monitoring the building pressurization? So some of these details are things that you definitely want to have upfront and understanding how that's going to impact how your building's going to operate. Because I know we focused a lot on economizers, so, where equipment that's intended to reduce energy load and try to keep cooling capability within a building. And if those aren't set up correctly and that could be anywhere from just bent louvres to valves that are working correctly, or a wide range of different operational issues. When you go to try to convert to a smoke operation plan, which we call it smoke readiness, you may not even be able to do that because your equipment's not, hasn't been maintained. So we talked a little bit about when do we start? At what point do you say, okay, I've made all this planning, I've got my filters.

    I know what I'm going to install. So when do I do it? At what point is that action? And that action, it's going to vary between the operator, operator, region to region. So I talked a little bit about PM 2.5 in instruments a little while ago. There are a lot of low cost PM 2.5 instruments that are now out there. I don't want to mention any names, if you do a quick search for PM 2.5, you're going to find at least three or four different manufacturers of instruments that when I say low costs, they may range from say $200 US up to $400 US. So again, when someone, one person says, "Low cost" another person says “I can't afford that." So I'll let you determine where your level is on the cost aspect.

    But a few of these sensors are installed during the off season. You can get an idea of how your building is normally, because PM 2.5 exists. It's everywhere. We have it all the time. If you're in an urban area, it's going to be more than if you're in a rural area. And when that meter starts showing you, you can tell there's reports of, the outdoor air quality reports are starting to say that your AQI, if you're in the US or AQHI, if you're in Canada is getting poor. There's variety of different prediction websites that can tell you if there's going to be a plume of wildfire smoke. And we've been through this a few times, so you should kind of have a feeling of where you are, when the smoke's going to hit. So depending on all of these factors, you can decide, okay, it's time to enact my plan.

    And I think another aspect of this is being able to have some of those monitors in place. You can kind of see if what you're doing is having an impact, because there's nothing worse than spending thousands of dollars on filtration or changes to your system and then not really knowing what you're doing, because I mentioned this before fighting that odor issue can actually be very challenging. If you're outdoors, outside, if you're in a building where you're you have customers and they're outside and they're coming in, they're bringing that smoke smell with them. And they're actually releasing some PM 2.5 themselves, but that odor is going to be there. So those complaints could persist. But if you have some of these sensors and you can show, look, outdoor could be very high. I don't even want to say a concentration because it ranges.

    We see reports during some of these wildfire events. Those you see in the media, the worst air quality on the planet, and it can happen for a couple of days or even a week. So that could be concentrations well above 200 micrograms per cubic meter, which is where your concentration units might be. So you look at this, say outdoor you’re one value, indoor you're this value. Plus you could look at that sensor, that data, and say, "Look, I need to tweak the system. My plan was X, and it's not quite working out the way I need to so I need the tweaks." So again, the intention of the framework is to give you a starting point and to point out some things that you need to look at. We've covered some of them here. And the idea is that you're reviewing and checking how your system's performing.

    And again, you may have to report to management building or somebody, somebody's paying for this, they're going to want to know how their investment's going. So having some of these sensors is definitely going to be helpful for that. You can start to show that, because like I said, the smoke, that smell is going to persist and then you have the perception of poor indoor air quality. Again, VOCs, you can monitor VOCs but it's not as easy. The concentration range is like I said, a mishmash, but some of the scientific studies looking at characterizing say tobacco smoke or cannabis smoke, there's over 5,000 compounds in smoke. And smoke is a form chemical. So it changes as it ages.

    And you do get gases like ozone forming, as it changes, to nitric oxide, to your NOx compounds, you get all the “-hydes” and variety of other health relevant compounds as smoke ages. But monitoring these can be very challenging, it can be very costly. Again, this is I guess, why we're focusing right now on PM 2.5, because we do have data on the health outcome. PM 2.5 is a relevant contaminant. So this is the whole plan, the idea of plan, do, check, act, right.

    Mike Gallagher:

    So Greg, you hit a couple of points that I just wanted to touch on. First of all, positive pressure, that's the biggest difference with COVID. With COVID you want more and more outside air, which means that if you don't exhaust it, you're going to be grossly over pressurizing the building. We've got the reverse deal with smoke, because with smoke, we want the absolute minimum amount of outside air that still pressurizes the building. And the reason we want the minimum is because first of all, it's bringing in less direct smoke. We want it to come in through the system so that it can be filtered, but we want the filters to last as long as they can also, so that we're not up there constantly changing them. That's why that minimum positive pressure's important.

    You mentioned economizers. I mean, there's got to be literally at least 30 kinds of different controls over the years used on unitary equipment economizer packages. And so are you going to be able to find something that's easy and you could just simply hook up a switch to where you've got smoke and non-smoke, in most cases the answer unfortunately is no. Although some of the newer stuff for other reasons that are now code mandated or energy code mandated, you may be able to do that. And so designing for new installations, that's definitely something to consider. And while you're talking about that, my controls guys in our controls department tell me that the cost of a particular counter that would pick up 2.5 is actually relatively small. I can't remember the number they told me, but it sticks in my head that it was under 500 bucks US.

    And if you'd get a couple of those, stick them in return ducts. And if you've got an outside air intake, and if you wanted to stick one in there too, all you need is another point on your control system. You can monitor that, put it on the graphics. You could set it up for alarms. There's all kinds of things you could do to track. The last thing I'll throw in there is the importance of setting up this minimum outside air, figuring out what you have to do to your equipment to make that happen, marking it permanently, whether you do it with a Sharpie or some other way to mark it. And then also mark it in, where was it when I started? Because you have to memorialize both settings so that when you're done with the smoke event and you want to go back to normal, you know where that was.

    One of the things that we saw over and over and over again in Los Angeles last summer was everybody went up and slammed all their outside air intake shut during the smoke, thinking that that would bring less into the building. Well, of course they didn't shut off the bathroom exhaust. And as we used to joke, they might be ahead to do so and live with the smell because when you've got the bathroom exhaust going, and you shut out off your outside air, you're pulling smoking from the outside, through every hole in your building. And people may think they don't have holes in their building, but let me ask you probably the most obvious thing I run into. How many people do you think have installed external security cameras on their buildings in the last five years? Find me a building that hasn't done that, right?

    Do you think that they actually seal all the conduit penetrations for going outside for those cameras? No. Come on. Come on. So all of these buildings leak like Swiss cheese, the original building envelope is absolutely not, the integrity is poor. And if you're running exhaust fans and you cut off your outside air, you're just pulling direct smoke into the building. So this is part of the planning process, and it's part of setting up, finding the settings you're going to use for the minimum pressurization and marking them so that you can go back to them because we've got buildings in LA I'm convinced still that have the outside air shut off. It's been shut off since that emergency move way back during the fire and they still don't have outside air. So I think that's just reality, but it's not just a function of the whole building. I don’t know, Greg. What if you could do building and you just wanted to have a cleaner space?

    Greg Nilsson:

    So I know like with Health Canada, I believe EP as well, there's been a lot of documentation on trying to build or create a clean airspace. And I think there's another aspect of this that we've also mentioned in the framework that has everyone should keep in mind is that sometimes, I think you touched on that too, you can’t increase the filtration capacity of your system because just, it's older, it just doesn't have that capacity. Can't find the filters that will fit the system. You can't modify the system, it's too costly. So now what do you do? And that's where your portable air cleaning systems are going to come into play.

    And certainly they've even been used in healthcare settings in some situations because what your system can do may just be limited, or the conditions outside are just horrendous and the system, no system could handle it because you reached these points. So you can define dedicated spaces within your building and you could put in air cleaners. I know AHAM has a lot of information about that, so does the California Air Resource Board, you have to be mindful about the type of equipment you use because some of it can have unintentional byproducts like ozone, which is regulated. So you should look that up and keep that in mind. When it comes to air cleaners, I've been testing these for several years, we've come up with our own standards, even testing methods.

    And how they're tested when you get those labels, we'll mostly use an AHAM label, for example. So if you go and you buy your air cleaner has an AHAM verified label on it. They'll give you a clean air delivery rate. They'll say, "Okay, this is how much clean air it's going to give you in your space." And then you go and you stick it in the corner of your office with two desks around it and turn it on the lowest setting because the higher setting, which is what is tested at by the way, the higher setting is too noisy, you don't like it. And then you're wondering, well, why is this thing I just spent 500 bucks on not doing its job? Well, it's because you're not using it in the best way. So again, some of those planning processes with, if you find your filtration capacity can't work, or you just run out of budget on new filters or whatever that might be.

    It would be how your working space is set up, which areas you're going to focus on and trying to set it up so that your air cleaner, if you're going to install one can have the most open area around it. And of course, they're only tested in a 31 cubic meter space. So if you're going to take an air cleaner and stick it in a very large space, you're probably going to need several of them. And there are some documentations where they help you make some calculations to predict the different performance. But in reality, an air cleaner, that's designed to clean a residential bedroom is not going to do well in a big open office. It's only moving so much air. So you can even look at their commercial systems available that are around. You can again, look at these and this can become part of your planning process.

    In the middle of a smoke event is not a good time to try to run down to your hardware store and say, "I need the air cleaner." Because, chances are everybody did that. And you're going to be told to drive 500, oh, wait a minute. I'm talking in ASHRAE so 500 miles instead of kilometers down the road. Sorry, I had to push it that little bit. We love our units up here. Actually in Canada, we don't measure distance in kilometers and miles it's time. It's about an hour away. So you might have to drive for a few hours just to find your air cleaner. And then you may not be able to find the one that would be the best for your space. So again, that all comes into that planning phases, is if all of these little details that you're trying to sort out, and it's not an easy undertaking.

    I think that everybody on the committee understands this. This is an investment. It's an investment in time and energy. And anybody that worked in an uncontrolled space through California last year that couldn't, they just had to experience that through the whole time, I think they can attest that this time and energy that you put into this process will pay off in the long run.

    Mike Gallagher:

    I would agree. And other takeaways that I would get from this thing is that first of all, if you haven't looked at the interim guidance, the framework document, just pull up your search engine and plug in ASHRAE smoke event framework, planning framework, something like that. It'll come right up. You can look at it, got pictures, got step-by-step, got a planning process noted. One of the things you need to decide for your facility is what's good enough, is it okay? If it's better than it is outside, is that good enough? And what can we do? You're going to need to survey your existing mechanical system. Is it functional? Is it working okay? Or do you just not have temperature complaints because those are two different things?

    Then the question is, okay, what are we going to do to achieve this minimum pressurization thing where our filters will last longer and so we're not pulling in outside air. You're going to have to dry run. You're going to have to test it a couple of times, see how it works. And you need to record the settings before and after so that when you're done, you can go back where it was. One of the early stages is going to be how much budget do I have? Can I spend a little bit of money to have somebody check the system out make sure that it's okay. And tell me what I could do to make it better. And tell me what I can do to filter the outside air better as it comes in, which is a real key thing.

    And then if I'm going to have several batches of filters so that if I've got weeks long smoke events like we had in LA last year, if I'm going to do that, how many sets of filters do I need and how much space does that take? And do I even have any place to put all that stuff? There's just lots of these kinds of things to figure out. And if you don't start thinking about it and you wait until the event hits you upside the head, then by the time that happens, you're going to be wondering what happened.

    Greg Nilsson:

    Yeah. I think another thing to keep in mind is what actions did you take last year? How well did they work and how much can I improve it? Because we all have different memories and stuff, and sometimes we like to lie to ourselves and we say, "Hey, I know how I did this." And I think Mike said, "Write it with a Sharpie if you have to." But keeping records, trying to make sure that you have some kind of summaries, standard operating procedures, something that you can look at, review and say, "Okay, this year we spent X on the filters and whatever." And you can start to plan and improve your plan, and just also with the understanding that it may not necessarily work exactly the way you wanted the first time you enact it and that's just life.

    And we adapt and we move on and something Mike said, I'll just pop on is that, we are hopefully towards the near end of the pandemic, with my fingers crossed I say. And we've certainly made some modifications, and we've changed how we think about, how we operate our buildings, more fresh air, more fresh air, and all of these things. And unfortunately, some of these actions for wildfire smoke may not necessarily line up with that. I think as a building operator, if there's a take-home message, we have to start thinking about indoor air quality more holistically and planning, and we might have to make some value decisions on which contaminant can I deal with, which is more important for the health and wellbeing of the people in my office?

    And we work in the best situation, like what we're working on the guideline is to try to come up with solutions that answer everything, but that may not work in all settings so I guess, like I said, start thinking about air quality. And I think you jokingly said that thermal comfort. No one's complaining that it's too cold or too hot, I'm great, may not necessarily be the case. So we just try to improve that knowledge, shorten the knowledge gap and get some planning in place so we're ready to act when we need to.

    ASHRAE Journal:

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