 Hi, I'm Nate Adams, sometimes known as Nate the House Whisperer, and this is a topic that I ended up having more to say on than I realized and spent all of last week researching and then RetroTech, which is a Blower Door company, and I put on a webinar a couple of days ago, but it ran to about two hours and I was asked to do something shorter. So here we are. And so what's behind this is we breathe about 3,000 gallons of air per day, and now that we are all staying home to one degree or another, all of a sudden we have a lot more control over that air because it's inside of our own homes. So I wanted to talk about practical science-based steps that you can take to improve your air quality and reduce your risk of getting sick in general. It's not going to be just COVID-19, but it appears that this largely applies to COVID-19. Information is coming out very quickly, but the handful of studies I've seen specifically related to this look like it's fairly similar. It may not be perfect, but what I'm going to recommend, these are common do-no-harm type steps that, worst case scenario, they don't help. Best case scenario they do. Either way, they're very unlikely to hurt you. So let's just dig in. Here are the key takeaways I'm just going to lead with what you're going to learn. So there's three different ways that we can improve air quality and hence reduce the risk of contracting things. So humidity, filtration, and fresh air are the three tools. Controlling them more specifically. So what you want to do, your humidity, you want to stay in the 30% to 50% relative humidity range. You can push as high as 60, but be careful. When you start getting too high, particularly in colder climates, because we're still coming out of winter, you can get condensation and you can create mold and rot and other problems. So you have to be careful there. Second piece is filtration. So while technically COVID-19 is not supposed to be airborne, that means the actual virus particles are not coming off your skin. This is transferred from what I understand by being inside very small droplets. So when we cough or we sneeze, there's tiny little bits of water and spit that come out of our mouths and they have these tiny little virus particles in them. So if we can catch those and it looks like they stay airborne for several hours and they stay viable for it's the half-life is one hour and that is specific to COVID-19, that was a New England Journal of Medicine article. So filtering those outs, it may be helpful, it may not be helpful, but with the particle sizes we'll talk about it's fairly likely that it's going to be up in the air. So it's worth at least paying attention to. And then the last piece is fresh air, so that's bringing in outdoor air. And we want to keep the indoor carbon dioxide levels between 600 and 800 parts per million. There's a bunch of different ways to do that. I'm not going to dig in all of them, but those are the keys right there. Now, how do we do that? Humidity control, you are going to need more than likely both a humidifier and a dehumidifier, so you need to be able to add or subtract moisture at will. You need to have a MERV 11 filter or higher, and we'll talk about exactly what that means. And you want to have some way to bring outdoor air into your house, so you can do something simple like turn on the bath fan or the range hood as long as they vent outdoors and crack a window and you'll get fresh air in your bedroom that way. Or you can do it with HVAC. So all of these, they're simple solutions, which are inexpensive and I'll touch on. And there are more advanced solutions, which I'm going to save for other videos because I have plenty of other contents that touches on these subjects. So all right, one last thought before we move on. So filtration, humidity control and fresh air, these are nicknamed by my friend Caleb Salibi the holy trinity of indoor air quality, and I fully agree. So we're going to be talking about viruses in particular, but this affects everything. There's all kinds of different pieces that this affects. So regardless of whether or not it helps you in your home right now with COVID-19, none of these things are likely to hurt you. And in fact, this is a key piece of our ethos as a company at Energy Smart Home Performance and then also the new program we're working on, HVAC 2.0. It's first, do no harm. So we are doctors for houses and so we feel like that is an important thing for us to stick with. And so I want to mention too, you're going to hear a lot of marketing promises out here. It kills this, it kills that. No, there's nothing certain about this. Nothing, but all of the things I'm going to talk about here are likely to help and if they don't, it will be a placebo. So it'll be a sugar pill at worst. So I'm not going to dig into it in this video, but there's a lot of UV lights being slung out there. In fact, from all of my HVAC contractor friends, all of the shelves are empty of those products and they can cause some pretty big harm. There's different types, some of them are probably okay. Personally, I view them as an upper level solution. So it's like if the first drug or the second drug doesn't work or physical therapy, all the other things, then you look at UV. But this is not a first line of defense, it is a last line of defense. So if you have someone promising you the world that these killed the viruses and this and that and the other thing, please slow down. A friend of mine, his wife, was put in the hospital by one of those products because she has asthma and it added a lot of ozone to the house. So please be careful. I don't view most UV products as passing the first do no harm rule. And even if they did, there's other things to try first. Okay, that's enough. Let's dig into a little bit of the science so that it makes sense. So when it comes to filtration and we're going to back in the humidity through filtration which is funky but it will make sense in a minute. So particulate matter is very, very, very small dust. So it gives you an idea here. This is a standard EPA chart that I've been using for years now. And a human hair is 50 to 70 microns. So just keep that in mind, 50 to 70, 50 to 70. Now what we're looking at are very small particles. So we're looking at PM10 which stands for particulate matter, 10 microns and below. And PM2.5 which is particulate matter, 2.5 microns and below. So you can see there on the hair, these are really, really, really small things. And these are the sizes of the droplets or aerosols that come out of our mouths when we cough or sneeze. So these are what we need to be able to filter out of the air. And here's why these matter. So these are the different sizes. So PM25 is pretty big, you know, that's half the size of a hair. PM10, when we get to that size, we inhale it, it goes into our mouth. PM2.5, it goes into our lungs. It's small enough we can get that far, not all of them will but some of them will. And PM1, so 1 micron and below is so small that it will go into our lungs and straight through our lungs into our bloodstream. So that's bad news and also a decent chunk of the particles or of the aerosols. So particulate matter is dust, it's actually like hard stuff. Droplets are larger droplets if you will. I think that's PM25 is what I was told is the bottom that it goes to. And then they changed aerosols. So the small aerosols are what are carrying the viruses and what can get into us. So ideally we filter those out. Also the PM1 is really difficult to filter from what I understand. So it's a double whammy. So first the small particles, so when you get below 2.5, those particles can stay in the air for hours or days. They are not heavy enough to naturally settle out. So it's a good idea to be able to filter them out. And PM1, it's really difficult to filter and it stays in the air. So that's a particularly challenging application from the air quality researchers I've spoken with. Okay, I am borrowing this from Dr. Lindsey Maher who is at Virginia Tech. This was a great little video. That's pretty geeky, but if you want to dig in I'll put a link in the notes. But take a look at the virus size. So we were talking about PM2.5. So this is PM0.5 that you're looking at on the right. So that's right here. This is PM0.5. So this is the droplet or actually the aerosol that a virus particle is being in. So the virus particles in this instance, she's showing it as 0.1, they can be as small as 0.03. So they're very, very small, very difficult to filter. So if you want to filter them, ideally you want to catch it while it is in the droplet. And from another one of my researcher friends, I asked what happens if that droplet goes into the filter, gets caught, and dries out, is the virus going to stay there? The consensus is that the odds are very good that it will. There was something about the Vanderwall's principle. And don't ask me what that means. I really don't know. I have to Google it and figure it out. Now from the same presentation, Dr. Marr, this was looking at influenza A. So this is not COVID-19, but this is a virus. And what she found was 70% of the aerosols, droplets, or particles, whichever way you want to call it, that carry the viruses were below 2.5 micrometers, or microns. So that is small enough that you need a very good filter to be able to tackle. And so here's what you actually need. These are standard filter varieties. So Merv is the standard name. This actually has a standard behind it. So some of the other ones you'll see that will say like allergy arrest or something like that. They're making it up. That is a marketing name. Because one inch, little small filters, they generally stink. And if you try to make them good, it's all about surface area. And they don't have enough room to have much surface area. So they're very restrictive. And they will tend to break your HVAC if you just go put a good filter in right now. But Merv's, take a look here. So Merv 3, these are really crappy filters. We joke these are good for stopping large rocks and small children. What you really want to do, you want to get down to the Merv 11 range. So look at the stuff that it's taking out. So at Merv 11, you can start taking out bacteria, odors, feces particles, which is kind of funny. But at Merv 13, look at this virus carrier particles. It's not going to do a perfect job on that. Not at all. In fact, this is too much to put on a slide, but I'm going to do it anyway. This gives you an idea. So up here, take a look. This is 3 to 10 microns, 1 to 3 microns, and 0.03 to 1. This is where virus particles on their own live. This range here is where most of the aerosols droplets live. So these are the ones you want to be able to filter out. So step on down. Our minimum traditionally is a Merv 11. Note that in the 1 to 3 micron range, it does a good job. So 2 thirds to 3 quarters, it knocks out, and the larger particles, 85% or more. So that to me is the bottom of what you want to use. Ideally, you use a Merv 13. And as you go higher, you create more and more back pressure. So it's harder for the air to go through a system, and you can break it. There's a lot of bad things that can happen to the equipment. So you have to be careful with this. But we do use Merv 13 on a number of our projects. And note this, 0.03 to 1, less than 75%, but that's the first one that doesn't have under 20% on it. So this is where it kind of begins. When you get into 17 to 20, this is HEPA, and it's not truly HEPA because the certifications are done differently, but consider above Merv 16 a HEPA filter. So those do a very good job. So let it be known, Merv 13 or higher for this work is best. So now we need to back into humidity. So the particles that these little viruses travel on, the aerosols, the bits of our spit, they will get smaller if it's dry, so they'll evaporate. So the ideal place, and there's several other reasons for it, at least don't ask me to explain all of them. I don't fully understand them. But having done a lot of research, the 40 to 60% range is considered optimum for these. The curse of 40 all the way up to 60% is you want to be careful running on the higher side because you can get condensation and mold like I mentioned earlier. So you can live there for a couple of days, maybe a couple of weeks, don't live there long term. Something bad will happen inside your walls and you won't like it. So we recommend 30 to 50% range. And this is a standard chart that's been out for years. So look down here, 1986. This is not new information. And this was done by a bunch of ASHRAE engineers. But take a look here. So this is a list of viruses and this is relative humidity on the bottom. So when you get into low humidity, you get much faster virus spreads. So you want to stay out of the bottom and you also want to stay out of the top. So ideally 30 to 50% for buildings is best and general air quality. If you need to push a little bit higher, so be it, but be gentle. Be gentle. Now the other piece of this is fresh air. And by the way, in the longer presentation, I go into humidity a lot more deeply than I just did. So if you like, hey, that's kind of fast, fine, go watch the two hour one. It took a long time to make the argument. So fresh air. This is important because it's good for our mental function and our healing powers. So this is a Lawrence Berkeley National Lab study from 2012 that found that if you bumps carbon dioxide levels up to 2,500 parts per million and atmospheric is 400 to 500. So that's what you're in outside. But when you bump it two, five times that, you start really hurting mental function. So these are a bunch of different tests and they found that mental function was falling off a cliff. At 1,000, they were seeing some results and 1,000, that used to be the target for air quality. So that's all the more they were looking for and that's already starting to show signs. Now bedrooms in general are going to break 1,500 parts per million at night. So this is something to pay some kind of attention to or at least be aware of is that you want to hold those CO2 levels down if at all possible. If you sleep with someone else in a room with a closed door, the odds are almost 100%. You're breaking 1,500 at night if you don't have windows open or something like that. And it's quite possible you're getting to the 2,500 range. So I watch all kinds of things like this. I don't know if you can see behind me. I have 11 air quality monitors in my office and we have 40 out in the field recording right now. So these are things that we watch and we pay attention to. So again outdoor air is 400 to 500, target indoors should be 600 to 800. So you can buy a monitor for this, they're about 150 bucks on the cheap side but that's not the first thing. I'd watch humidity levels first but fresh air is an important piece of the puzzle. And here's a really good reason why. So this study, and this is pretty new, it's only about a year old, it found that when rooms and schools were provided with recommended levels of fresh air, and I'm not going to get into what the recommended levels are, but when they did that it was the same effect as inoculating 50 to 60% of the kids against the flip. So will that cross apply, absolutely? Who knows? But in general these things, they work similarly, they just work in different degrees. It's usually what I see in doing this reading. So if fresh air is that helpful, it's a good idea to bring it in in whatever way you can. Now the curse of fresh air though is that it's not always fresh. So I would highly recommend getting an AQI, Air Quality Index app for your phone and watching it because you don't want to have the windows open all the time, particularly if the air quality outside is bad because you may be goofing up other things. So it's kind of a pain to watch but you really want to watch it unless you have an HVAC system that does this automatically. So speaking of HVAC systems, let's talk about what it looks like to fix these things or at least take the edge of them off. So in the way that we think, we view interventions as having four separate levels. So the first level is zero to a hundred bucks. This is stuff to try, it might be turning on your bath fan, it might be changing the setting on your dehumidifier, it's usually working with something you have or buying something inexpensive to try. But the goal of these is two fold A, do no harm and B, don't waste money, we don't want to buy something that doesn't get used later or that is pointless. Level two is a hundred bucks up to fifteen hundred bucks so that might be a dehumidifier, an air quality monitor, things like that. And level one and two by the way, these are all things to try to understand what's working and what's not. You want to go to a permanent fix because level one and two are generally quite temporary. When you want a permanent fix, that's generally when you need an HVAC contractor because all of these systems, all of these factors are basically controlled by your heating and cooling system. HVAC stands for heating, ventilation and cooling. You want to call an HVAC guy if you want some of the higher level stuff. And then level four, we do fairly advanced projects in our practice, which typically mix insulation and air sealing on one side and HVAC on the other. That may not be necessary, but if you get through level three and things aren't working, that's the next step. It's really taking a look at the house like a body. So it's looking at the house as a system of systems and playing with everything together to get the result that you want. But that's not normal and that requires quite a bit of planning to do that. Now the tricky part of this is though level three, if you don't do any diagnostics, is really risky. So before you go spend two grand, five grand, ten grand, I highly, highly recommend that you do some measuring and you try and understand what the problem is before just throwing money at it. Because all too often we see people waste money on these things. So be cautious. It's important to be cautious. All right, let's just look briefly at a couple of different things to try. I'm going to stick to level one and level two. So for starters, humidity looks to be probably the most important factor. So if you don't know what the humidity is, you can't control it. So a client just showed me this particular product. It's called a GOV, G-O-V-E-E. And this is 20 bucks and it's actually a data logger. So there's an app on it. It holds a couple of weeks of data on it and the app will hold a couple of years of data. So you can watch what your levels are and look for that. You want 30 to 40 percent if it's cold outside, 40 to 50 percent if it's warm outside. And if 50 percent is hard to hit, you might consider increasing your air conditioning set point. Instead of keeping it 70, maybe keeping it 72 or 74. But if you're dehumidifying to pull that down, you may find that more comfortable. And that should be better for controlling viruses as well. Okay, but it's important to measure because you can't manage it if you don't measure it. Another thing to consider is just a room humidifier. So 40 or 100 bucks, they're not that expensive. It is important though to put clean water in these because whatever is in the water is going into your air. So it's best to use either distilled or reverse osmosis water in these. And then the last thing, this is an ugly one, but this is called a filter fan and this is really simple. This is by a Merv 11 or higher filter, preferably that Merv 13 like we talked about. That's 20 by 20. So it can be taped onto a standard box fan. So if you have a box fan sitting around, tape a filter onto it with duct tape. And that's basically it. Now this one's backwards. This filter is on the front because I didn't pay attention when I bought this fan years ago and the switch is on the back of it so I can't put the filter on the back. You want to pull the air through the filter so that you don't get the blades dirty. I'll do a video very shortly on building one of these. And then these are what the filters look like and go take a look at Amazon, there's a bunch of these you can get there. And Shelly's tip here, this is my friend and researcher Dr. Shelly Miller. She suggested considering activated carbon that helps knock chemicals out of the air. So if you live in a place that's close to a road, that will help reduce volatile organic compounds, nitrous oxides and ozone as well, all while being very innocuous. And the other thing to consider is if you have a range hood or a bath fan that vents out doors, you could crack a window, turn it on and that will suck air out. Curse of this is as we get into one season of the other, if it's humid outside you're sucking a lot of humidity in and that may make humidity hard to control. If it's really cold outside, you're going to bring in dry air and you're going to need to add more humidity to offset that. So this is kind of a game and it's again ideally done in an automatic fashion with your HVAC. But these are inexpensive things that you can try now and have good likelihood of helping and very low likelihood of hurting. And the last piece that I'll talk about here is just a dehumidifier, nothing fancy, just like a basement dehumidifier. Set it to 50 or 55% and let it rip. Bad part of these is they usually only last a year or two, so that part does stink. So level three, this is something to just back up and talk about. So we have cheekily named system that we put in all the time and this is not patented or copyrighted or anything, this is just a concept. It's pulling together a bunch of best practices and we call it badass HVAC. And what badass can do is it can tackle all six functions of HVAC. So several of these are going to look familiar. So we've been talking about filtration, dehumidification, fresh air, and humidification. This is pulled directly from the HVAC 101 chapter of my book which is a free download. So I'll post a link here. But what HVAC also needs to do is load matching, which is matching how much heating or cooling is being put out to exactly what the house needs at any time and right place at the right time or mixing. This is stirring the house and filtering it continuously and moving the air around. So those are important things that main HVAC systems can do. And badass HVAC we have purposely set up so that it can do all six of those functions with one piece of equipment. So this is not a really expensive, exotic system to do. And this is basically what it looks like. So those six functions all get tackled. So I have a contractor focused video for this and I'm just about to do a homeowner focused video for this as well that walks you through all these pieces. Okay, so that is the basics. So you want to do humidity control, filtration and fresh air. If at all possible you can do it with inexpensive pads or particularly the next time you buy a new HVAC system you can have badass HVAC done which will control all of these automatically. So you aren't running around opening and closing windows and having to watch a bunch of things as you go through this. But at least there are some really nice spot things that you can do that really look like they help so you can do that. And surely you're going to have some questions coming out of this. So highly recommend if you're on Facebook join the Electrify Everything Facebook group. So that may seem like a turn but one major piece of air quality, like outdoor air quality is made poor almost entirely by burning things. What this whole conversation really is is air quality conversation narrowed in on COVID-19 and viruses. So go there if you're a homeowner and ask questions, keep the discussion going it's a great place to go. And if you are a contractor go check out the HVAC 2.0 advanced discussion group. So we can dig into that on the professional side and contractors are welcome over here as well. So anyway that's that I'm Nate Adams hopefully that was helpful and that's a lot faster than two hours but if you do want to go deeper into all of these things you need to watch the full webinar. I'd love to tell you otherwise but it is what it is. This is not a simple or fast topic. But anyway I hope that was helpful. Have a great day and stay safe out there stay healthy. This is something that we can beat and frankly I am loving watching the human reaction to all of the COVID-19 crisis because this is it's really cool to see both the best and the worst of human nature but an awful lot of the best. So stay safe stay healthy and I'll talk to you next time bye bye.