How Much CO2 is Healthy in my Home? Carbon Dioxide Targets Planned and Proven

CO2, carbon dioxide, is a gas we exhale. It's used as a marker for indoor environmental quality because if our emissions of that are hanging out in the home, then any of our other odors, viruses, skin particles (which make up a lot of household dust), etc are also filling up the home. On an airplane, for example, which 'they' say is one of the most ventilated indoor places you can find, you can easily prove when they turn the outdoor air off while you're sitting on the ground, because the CO2 spikes upward of 2000 or even 3500 in our experience (and therefore, any of the COVID laden particles are also obviously building up).
CO2 is not everything, in fact you might have a low CO2 level only because there aren't many people in the home, or the home is big enough to dilute it- you might have other markers showing the home suffers from poor ventilation, like formaldehyde, humidity, particles, TVOC, radon, and so on.
But it's something that can be easily measured, so let's measure it and try to optimize for 1000 ppm as the max in homes, along with all the other factors.
The two devices I use in this video, and everyday in our own home, are the Aranet4 (get 5% OFF with coupon code HMDG at aranet.com/pro...) and the Airthings Wave Plus (www.trutechtoo....
The 5 Factors of Ventilation are: • Home Ventilation's 5 F...
Learn WAY more about how to strategize the 5 Factors of Ventilation with our Ventilation Course at: buildingperfor...
See the Broan Overture system for controlling all of this: • Automatic Ventilation ...
Consult with Corbett on tuning any home, anywhere: buildingperfor...
Watch the first-ever TV series about the Science of Homes: homediagnosis....

[@mikegrok]

BTW, whatever CO2 meter you get, test it two ways. #1, open a can of carbonated soda next to it. The CO2 should go up. #2, put a cap full of rubbing alcohol next to it, if it measures VOCs, that will go up, but if CO2 also goes up, return it and get something else.

[@HomePerformance]

Ooh, good one Michael. I have the same issue with most CO monitors- they go off if exposed to coffee (or flatulence).

[@tullgutten]

As i love tinkering with electronics i take apart everything i buy before even testing it and found that several "co2" sensors that cost less than 40usd is really not measuring co2 in any way but using a VOC sensor and then spit out a random eco2 number that is far from real. If you search for NDIR Co2 sensor you find the real ones (airthings is using a real sensor) In my home i have 2 co2 sensors smart home connected and an airthings plus and have the ventilation to turn on above 700 ppm co2 and/or high voc, humidity or pm2.5. Keeps a great indoor air quality And as he said, test if it is real by a soda bottle or mixing baking soda and vinegar to produce clean Co2. And hold a can of solvent and carefully whiff it around and see, if it reacts to solvent and shows Co2 it is fake like many cheap products unfortunately are. (i have one, and it says indoor is 370ppm when outdoor is 450ppm and really indoor is 650ppm and it never is close to real value..) Haven't finished the ventilation yet so bedroom is only open door and it easily passes 1200ppm when i sleep. Livingroom is only above 700 a few minutes a day

[@HomePerformance]

Nice

[@shubinternet]

The AraNet4 has an NDIR sensor. That's one reason why it's one of the best portable sensors on the market.

[@Ariccio123]

#3: if it's ever below 420 when outside, it's junk.

[@heatherphilips9227]

I have 2 Winix 5500-2 air purifiers in a 12* 10 (120 Sq- Ft) bedroom. I also have the HOTKREM PM 2.5 meter (non CO2 version) as well as a the Aranet4. The Winix 5500-2 units clean the air so well, the PM2.5 meter will sometime say 0 on all particulate matter, including the ultra-fine particulates in the .3um range. My issue is, as the air gets really clean in my closed-up bedroom, I have to eventually open a window, because the CO2 levels will start to go past 1000ppm. It's frustrating, I just purified the air, and now I have to open a window for 10-15 minutes and let in dirty outside air, to bring the CO2 levels down to around 700ppm. Rinse and repeat many times a day, if I'm home and off work that day. There has to be a better way to keep CO2 levels in check, without having to open a window every hour. I do not own the home, as I rent the room. The home is approx. 45-50 years old, single floor dwelling. Any ideas would be helpful.

[@Ender_Wiggin]

That is a tough problem if you can't make any major changes; like adding fresh air system that would be filtered. Maybe there are window style fresh air filters that you could get or make your own. Also I would not keep the air so clean as to read 0. Will just be changing filters constantly. There is also research to show that too clean of an environment can be more detrimental then beneficial. The body works on a use it or lose it principle at its base function. If your body is no longer being challenged by airborne microbes or other environmental contaminants it may just stop defend those vector less. This can make it so you can become sicker faster once you do have to experience those environments. On the flip side if you already suffer from a compromised immune system or are of old age limiting exposure may be better. Side note: We still don't know why people that live in the appalachian mountains are some of the longest lived despite being exposed to significantly more radiation then most. The thought is that at certain level the body kicks in self repair mechanisms but if the radiation levels are too high or for a short duration these mechanisms don't happen. The argument against is those that can't tolerate higher level of radiation just died off much earlier and we only see the strongest.

[@rickjanosky6191]

how much do household plants help lower CO2? thank you

[@Frondlock]

very very little. To have plants to a point the make a significant effect on the CO2 in a room you would need to have 40 or 50 plants and all of the types that are known to suck a lot of CO2. It's not noticeable. Interior plants have a lot of benefits but not really on CO2 levels in a home.

[@car_tar3882]

Imo this is a bit crazy it’s a bit of a nerd thing I get but you’d likely get more benefits by going outside frequently or just open your window when convenient keep plants in your home

[@tealkerberus748]

No, please do put the CO2 monitors right next to where you spend most of your time - sofa or bed or home office. That's the air you're actually breathing. The air on the other side of the room or in a room you never go into is simply not relevant to what's going into your lungs.

[@cellocovers3982]

Any thoughts on using indoor plants to decrease elevated CO2?

[@frankgall6]

❤

[@justinherman9443]

Plants don't decrease CO2 enough compared to a single human. A human will release around 300g of Carbon in a day while a 15cm pot house plant will consume around 0.8g of Carbon. So you would need to have around 400 plants all operating at peak growth in order to offset the CO2 of a person. greenplantsforgreenbuildings.org/wp-content/uploads/2014/01/Project-Carbon-HortScience-474.pdf

[@HomePerformance]

Please nobody put 400 plants in their home- the humidity and microbe side effects would be hideous.

[@justinherman9443]

@@HomePerformance Sounds like someone would be living inside a greenhouse if they tried that!

[@HomePerformance]

You’d be amazed at what people will try when they heard about it online

[@covoliconstruction2407]

I am testing two CO2 levels, the EDYCARX and the AZ 7530. Both controllers are in the same room, but the difference in reading the room is about 300PPM. Do you have experience with these CO2 monitors?

[@firesofcreation]

Is it possible to install a house air filter system that can return CO2 ppm to the levels they were when you were born? For me, In 1974, the atmosphere was 330ppm.

[@HomePerformance]

There ARE CO2 scrubber filters, look in commercial HVAC equipment lines.

[@negodoy]

Thanks for this video! My bedroom is partially a subterrean. Upper half is on garden level and it has windows but the air doesn't circulate much and in winter I can't open it because of the cold. Do you think an extractor like those found in toilets would be useful to remove the bad air and pull down the good air from upstairs?

[@terenceiutzi4003]

I wouldn't worry about CO2 I would work about hevey flammable gasses first.

[@negodoy]

@@terenceiutzi4003 hi thanks for your response. Co2 during the night it is around 1300-1600ppm. Wouldn't that be a problem?

[@Ender_Wiggin]

CO2 level never goes up because we don't have friends

[@larryseibold4287]

Another great video. My back of the envelope calculation says that you need about 20cfm per person to keep the indoor air CO2 level under 2x of the outdoor level (

[@HomePerformance]

We have that party on a day when we can be outside on the deck, or at least indoor/outdoor. It’s Atlanta, not that hard here. If you were in Minneapolis I’d say rent an event space.

[@HomePerformance]

By the way Larry, I calculate that adults exhale about 0.5 cfm max, is that your figure too?

[@larryseibold4287]

@@HomePerformance That is close to my assumption, Corbett. I used some rough numbers. I assumed 1/2L per breath and 20 per minute getting me to 10L/min (0.36cfm) vs your 0.5 cfm. I realize that simplification can go one more step than I did. As I understand it, we exhale air with a CO2 concentration of around 40,000 ppm, which is approximately 100x of the outside air (~400ppm). We then know that we need 100x as much new outside air to achieve approximately 2:1 concentration equilibrium of 800 ppm (first order approximation). With my above breath rate that is 36cfm of fresh air, with yours 50 cfm. Obviously it gets easier to dilute as the indoor concentration goes up (ratio goes down). The biggest challenge in my house is the master bedroom at night with the door closed with two people. It is also where I want the lowest concentration for 8 hrs. Circulating the whole house air handler helps a lot with that by increasing the buffer, but I aim to improve the situation over time. I think it is worth pointing out that I think that the lower safe limit for CO2 concentration is 5000 ppm (0.5% used in breweries and green houses, OSHA 8 hr exposure). There are meters that alarm above this level. I am not particularly afraid of CO2 per se. I use it as a proxy for many air quality things, and desire to keep it well under 1000ppm, which also nicely corelates with the recent cognitive functions papers on CO2. I do not enter buildings that i know to have concentrations substantially above that unless the need is great, and then i wear a well fitted 3M N95 mask and get out when i can.

[@DmitryMyadzelets]

@larryseibold4287 What an excellent calculation you've done! Thank you

[@xax]

0:19 when you say “research show” to validate your content you should included a link to said research in the description

[@alexthekunz]

Agreed. I've heard similar claims in the past, so here's a random research article: www.ncbi.nlm.nih.gov/pmc/articles/PMC3548274/ I didn't look into this long, so I wouldn't rest my life on this being scientific consensus, but this was easy to find.

[@tealkerberus748]

1000ppm is the level at which acute carbon dioxide poisoning symptoms become so apparent, we're actually conscious of them. For most poisons, the chronic poisoning level that will cause harm if you're exposed to it for a few decades, or if pregnant people, infants, and young children are exposed to it for any significant length of time, is a much lower dose than the acute poisoning level.

[@shubinternet]

So, I'm curious to know what you think of the IQAir Perfect Air whole-house series? Or the IQAir AirVisual CO2/AQI monitor? Note that there's also an Aranet Pro or Pro Plus Base station that can let you network up to 100 Aranet 4 sensors together as one big system. I haven't tried it yet, but I am very curious to know what people think about it.

[@ipsumlorem3076]

I use it with an outdoor monitor to control an ERV based on both conditions using IFTTT and a smart electric plug. The software is a maze and could be better but the actual monitoring and the ability to hack together smart controls works well. It uses a lazer for refraction and a trained neural net to get accurate readings so it's a pretty good sensor.

[@cellocovers3982]

Any opinion on using the Air Advice M5200 monitor when at a client's home? Do you use that monitor or any other monitor at a client's home?

[@HomePerformance]

I use the Testo air monitors, but only for temp/rh/co2. By the way, who is Cello Covers? Are you one of our Patreon members?

[@cellocovers3982]

@@HomePerformance Yes I'm zacharyp32

[@jeffkirk4761]

I have a fresh air intake fan on my home, but not a CO2 sensor yet. I am curious, if I place large plants (4'-5' Palms) throughout the house, will that make a measurable difference?

[@HomePerformance]

Will not Jeff

[@tealkerberus748]

If you want to use plants to decarbonate your indoor air, first look at the statistics about how much carbon dioxide a sedentary adult exhales in 24 hours - if you're doing workouts or manual labour inside your home it goes up a lot. Then calculate how many full-time-equivalent sedentary adults live in your house, because the hours you're at work or otherwise outside the home don't count. For children, if they eat half as much food as an adult, they're half an adult equivalent. In round numbers, for every 44 kilograms of carbon dioxide, there is 12 kilograms of carbon and 32 kilograms of oxygen. You only need the plants to remove the carbon - photosynthesis will give you back the oxygen. So multiply the previous number by 12/44 or 3/11 to get the amount of carbon in your household exhalations. That gives you how many kilograms per day (or other weight measure) of pure carbon equivalent you need to be removing from your home. The next bit is harder. For the plant species you want to grow, you need to research the percentage by weight of carbon in the dry mass, and the percentage of water in the living plant matter. You use this to calculate how many kilograms of living plant matter you need your plants to produce each day to use up the carbon you are releasing into your home. The critical part is not how big your plants are, but how much dry-matter-equivalent plant mass they are adding each day. So rather than large slow-growing plants like big palms, you need something small, fast-growing, and using grow lights to photosynthesise. If you're doing this with something like salad sprouts or microgreens, remember that what you need is green tissue growth - the white stems are just made up of dry nutrients supplied by the seed, mixed with a lot of water, so that's not doing you any service at all. Obviously you're going to need to remove plant mass from your system routinely. And plants aren't made up only of carbon and oxygen from air and hydrogen and oxygen from water - they need a whole lot of other nutrients as well, which you're going to have to provide for them. That's going to cost money, and you're going to be spending a fair bit of time looking after them, so you probably want to figure how to make this a paying business. In theory it can be done. The planetary ecosystem has been doing it for over two billion years. I haven't heard of anyone making it work as a household system yet.

[@falinor181]

Do ERVs (that allow the exchange & balance of gaseous H2O) also allow the exchange & balance of CO2? That would defeat the purpose of the ERV dilution air, as CO2 would be transferred into the incoming air vs being exhausted.

[@HomePerformance]

Very interesting question, John, and I have no idea. I will ask at the AHR Expo next week, I have just the guy in mind.

[@ipsumlorem3076]

No. The core of an ERV doesn't mix the air. It acts like a radiator for heat and humidity but the air streams never directly meet

[@HomePerformance]

His point, I think, is if H2O can pass through the membrane, can CO2 as well?

[@dakotachapman9151]

Curious if you have a cost effective solution for increasing the dilution? Our home has a single return (1550sqft) and CO2 average is 1100 with two adults and a dog. All other IAQ variables are in healthy ranges. Have attic and basement access. In mixed humid climate.

[@Clyde-2055]

There you go, blaming it all on the dog …

[@andrewdelapp]

Getting an airthings monitor like you have was very eye opening regarding CO2. It explained some of the headaches we were getting before getting our ventilation fully hooked up. It was hard to buy based on amazon reviews, but now I know why it isn't rated 5.0: it is a fickle beast to satisfy without proper ventilation. I could see putting it in an expensive home and it reading "red" constantly and being really upset with the "thing".

[@terenceiutzi4003]

So you have over 5,000 PPM CO2 in your home? And where can you buy a CO2 monitor? I have been looking for one for over 20 years. I have been using an oxygen meter and doing the math.

[@HomePerformance]

@terenceiutzi4003 you sound like a very interesting thinker. There are lots of studies about this topic, highly recommend them, or stay tuned here.

[@terenceiutzi4003]

@HomePerformance I am a confined space instructor and have worked In that field for over 40 years. We haven't had CO2 monitors for 30 years, but our 4 gas analyzers . We just monitor toxic gasses, flammable gasses, and O2. I have worked in 17 percent O2 for 8 hour shifts with no trouble. That means 4,000 PPM CO2. The warning to evacuate sounds at 16 percent O2 or 6,000 PPM CO2.

[@Clyde-2055]

@@terenceiutzi4003 - Okay Terance, how long would it take a 60-sq m closed classroom (without forced-air ventilation, no heat or ac) with 25 45-kg kids (seated, taking notes) to go from a baseline 800 ppm to 2500 ppm CO2 level?

[@AdityaMehendale]

If you could use chemical means (hypothetically) to take CO2 levels _below_ 430ppm - would this offer _any_ health-benefits? I can think of a dry CaO tank "scrubber" that could be first "used" indoors, then heat-released to the outdoors when "consumed" to regenerate the CaCO3 back to CaO (as a hypothetical example).

[@HomePerformance]

Theoretically, I think it would matter a lot more if you could also take a bunch of other pollutants down to ideal levels: particles, formaldehyde, ozone, dust mites, fungus spores, annoying noises, and body odor.

[@shubinternet]

So, there are things you can do with IQAir HyperHEPA filters, even on a whole home basis. Filtering down to particles that are smaller than a virus can really help clean the air of a lot of bad stuff. But that's still only one step, and you will need to do more than that. If nothing else, that's not going to filter out any of the gasses -- like CO2.

[@AdityaMehendale]

@@shubinternet But *if* CO2 could be brought below 430PPM - would this be beneficial at all? Or is this the evolutionary "background level" that the body is used to have, and therefore perhaps een *needs* such that

[@AdityaMehendale]

@@shubinternet .. similar to how excess minerals in water are bad for health, but drinking DeMi water is worse..

[@cupbowlspoonforkknif]

@@HomePerformance When you find a filter for annoying noises let me know! Haha

[@doejon9792]

How precise AirThings compared to Aranet4?

[@HomePerformance]

Different sensor type, so not as accurate

[@Ann199040]

the CO2 in my house is super high, always above 1000 when window closed, at night , it can reach up to 1500, I have no idea how that happen, and if I open all window, it goes to around 500-600 at most, wondering if heater, water tank those kind of thing will affect the level of CO2? I am just trying to find way to reduct it. open window is good, but once we close, it soon will increase back to above 1000 ppm.

[@PhotoKaz]

yes, me too, I wonder because my landlord's meter is often going off, he moved it out of the kitchen to a back room and it still goes off, I'm wondering if his air freshener sets it off.

[@peterzolja6896]

So what happens is that opening windows does not recycle all the air from the home. It mostly exchanges some of the air near the window (within a certain area). How fast this happens also depends on the temperature difference from inside vs outside. If they're close, there's very little exchange (assuming no wind). The best solution (if you don't have an ERV) is to use a house fan or a box fan near a window that pushes air out with an open window in opposite side of the home. This forces a true air exchange that doesn't rely only on the temperature/moisture delta. However, even with all this we're surprisingly good at generating CO2.

[@johnfstockland]

In my bedroom (small 8m2) with no mechanical ventilation and door and window closed I get up to 3000+ in the morning. Thinking about how to improve it. How much would adding a vent grill (like the ones above windows) to the door help? There is a ventilation grill/trickle vent above one window already, so it would add some in-out airflow. Wondering how much I can improve with natural ventilation before looking at adding mechanical ventilation?

[@terenceiutzi4003]

For 2 people, that is normal in a room that size. That is well within the acceptable range for human occupancy.

[@justinherman9443]

I love my Airthings. I have a Wave Plus that I can take for portable metering and three View Plus (one on each floor of my house). I can easily see when more people are at my house in the numbers reported. I started on this path as I tightened my home I wasn't going to be poisoning myself or my kid with CO2 or Radon.

[@terenceiutzi4003]

Put an exhaust fan in your basement. That is where all of the CO2 is

[@justinherman9443]

@@terenceiutzi4003 that is not what my data shows. The co2 is where the people are.

[@terenceiutzi4003]

@justinherman9443 Yes, over 90 percent of the CO2 that man contributes is from 8 billion people exhaling 2 KG per day! The more people in a building, the higher it goes. Iwas working in a confined space years ago. So I was wearing my 4 gas analyzers. I walked into the guard house to tell security I was done and the low O2 alarm went off. The CO2 level in the guard house was over 5,000 PPM. I opened a window.

[@Clyde-2055]

@@terenceiutzi4003 - Buses, metros, airplanes, and classrooms, etc. … That’s where average people encounter the highest levels of CO2 …

[@terenceiutzi4003]

@Clyde-2055 wear the most people are. Years ago, I went to an environmental lecture in a university lecture hall. The presenter pulled out a CO2 monitor and showed us that in the hall, it was 3,000 PPM and explained that over 90 percent of the CO2 in our atmosphere is from people breathing.

[@jonetyson]

Exhaled breath contains 4%-5% CO2, but you can't exhale the entire volume of your lungs, so that a considerable amount of at least 4%-5% CO2 air remains upon a full exhale. I fail to see how 0.1% CO2 in the next inhaled breath can make any difference, given the much larger amount of CO2 already in the lungs before the inhale.

[@GeologyDude]

I recently bought one of these CO2 meters. It is surprising how high levels can go up in a closed, small bedroom overnight (w/o central heating)-during many hours of time (Up to about 1500-2000). Homes are sealed better now to prevent energy loss from heating, so that may be factor. Opening a window a crack easily solves the problem. But I’m not convinced how much hype is involved-regarding the “hazardous” interpretation of the high numbers though. The statistics say that exposure above 5,000 is bad, but 10,000 is the standard in the USA. However, several countries have 1000 as a standard. In general below 1500 seems best.

[@BrianVarick]

Are C02 levels the best way to determine the amount of mechanical fresh air supply?

[@HomePerformance]

No, you could have great CO2 levels but only because the home isn't very populated. If it's high, then dilution air is probably needed, but if it's low it might still be needed.

[@vfsd234]

​@@HomePerformanceso the only reason to have a co2 monitor is to watch for high levels? Normal/low co2 level is not meaningful? Please explain more. Thank you, love your videos

[@Monaleenian]

@@vfsd234 If the house is left empty for a period of time, you might find that the level of carbon dioxide could be quite low(because there has been nobody there to create a buildup of that gas in the house) but there could be a massive buildup of other harmful gases like radon. You could look at a carbon dioxide monitor's low reading of carbon dioxide and wrongly assume that there was no need to allow the air in the house to be replaced with fresh air from outside.

[@memjay9932]

OCD levels are very high here.

[@HomePerformance]

It’s a signature of our channel

[@Clyde-2055]

@@HomePerformance - Most commenters on your channel have obviously had no experience with indoor (grow room) chronic cultivation …

[@HomePerformance]

@Clyde-2055 yes, that’s certainly probable since this is not a grower channel

[@MrBrianDuga]

Great topic. I wonder how much indoor plants help - if at all.

[@HomePerformance]

I believe the actual research shows a miniscule effect

[@OPiguy35]

Amazing video yet again! Thank you

[@HomePerformance]

Glad you enjoyed it!

[@CG-ry7hz]

Do I need to be concerned if my garage CO2 levels go up to 1500 regularly? When the garage levels are up the family room (located next to garage) seems to go to 1,000 or a little more. Is this a normal issue for garages?

[@HomePerformance]

That’s probably combustion byproducts and air leakage between the home and garage. Yes, you should be concerned about the leakage.

[@car_tar3882]

Probably from your car may help to keep garage door open for a few minutes take of your coat get changed then close it

[@nitrorange]

There’s a study that finds people with attached garages get higher exposure to benzene. I’d make sure the garage is sealed well from the living area, and get some separate ventilation to exhaust from the garage. Do some googling and you’ll find lots of information. From a UK study: “In the homes where a car was regularly parked in the [attached] garage, 18-month average benzene concentrations of up to 101.3 micrograms m-3 were measured in the garage, which is more than six times the ambient air quality standard for benzene (16.25 micrograms m-3 running annual average).”

[@spencerwilliams3385]

When you say super nerd about CO2 levels, the concern is that measurement may preoccupy a persons mind and cause health anxiety disproportionate to the effect of elevated CO2 levels which they may or may not be living with already prior to intervention.

[@HomePerformance]

Sure, but with SO MANY PEOPLE denying science altogether, I’m willing to take the risk.

[@babartahir9004]

Plants also respirate, when light are out, their producing a lot more CO2 then O2.

[@JB-yq9bn]

In souther california in 100 year old leaky homes over 3000 for 80 to 90 percent of the time. Also tons of classrooms over 3000 - 4000 ppm.

[@HomePerformance]

Yikes

[@heatherphilips9227]

I'm curious as to how long a person can be exposed to, say, 2000ppm CO2, before the effects on cognitive function begins to decline. Before the internet and all this talk about CO2 accumulation, and monitors, I'd bet we all have been in rooms/locations where the CO2 was over well 4000ppm (without our knowledge) for hours. Now, with good monitoring and such, we see it hit 1000ppm, and freak out. There must be a time limit and maximum exposure rate to some degree before it has an effect.

[@Clyde-2055]

@@heatherphilips9227 - OSHA sets that limit you mention at an average of 5000 ppm over an 8 hour period …

[@joeshmoe7899]

Regulated ventilation with tvoc and co2. Tvoc was the challenge. If tvoc was controlled, co2 was also under control. When moving, sold co2 monitor. Wasn't using it.

[@theinfernalcraftsman]

Interesting numbers on the plane at the gate. Not surprising with that many people in it. Depending on the plane and airline and gate and and and... Air carts provide anywhere from 3-20 tons (ballpark ish numbers) of AC and they are pulling that air from the surrounding air at the ramp which is why you smell diesel when on the ground. So say an average of 2000-4000 CFM of that air pumped in along with everyone in it and assuming the ground guys didn't kink the hose like they do 99% of the time... In the end doesn't surprise me. My question is what were the numbers at cruise? The amount of recirc air varies from plane to plane. MD-80s don't recirc at all while others are 30-50% and it's run through a Hepa filter as well. People were led to believe that air on planes is all recirculated when it's not even close. But recirculated are is much cheaper than using bypass air to bring in fresh air from outside through air packs.

[@HomePerformance]

I see 1200-1500 on loaded planes at altitude, which was why I was always happy to wear a mask during peak COVID. Also filters out the fart smells from neighbors.

[@theinfernalcraftsman]

@@HomePerformance That's surprisingly high. IIRC the 737s only push about 12CFM per pax which is lower than older planes. But the high PPM explains part of why people are so much lets say harder to deal with on aircraft. The better half has to directly interact with them and has more patience than I do.

[@HomePerformance]

I agree

[@heatherphilips9227]

What about the flight attendants. They are exposed to high CO2 levels most of their shift. This is crazy stuff...

[@Clyde-2055]

@@heatherphilips9227 - I would think that continuous exposure would acclimate them to the slightly elevated levels of CO2, much as humans dwelling at higher altitudes have higher hematocrit levels …

[@markn2904]

Good food for thought.

[@mujaku]

The United States Navy did extensive studies of CO2 and it's effect on nuclear submarine crews for years. On board a US Navy nuclear sub CO2 levels can fluctuate between 300 ppm and 11,300 ppm. The level at which CO2 becomes dangerous for humans is around 15,000 ppm. When you talk about 400 ppm what you don't realize you're saying is that this is some of the lowest levels of carbon dioxide in 600 million years (the average is 2600 ppm)!

[@tealkerberus748]

It's also the highest in the past three million years. Humans have been "Humans" for about 300k years, so that's an order of magnitude back into our pre-human ancestors, all optimised for an atmosphere of less than 300ppm CO2.

[@Clyde-2055]

I just started researching this topic after my wife started yammering to change from an electric to a gas stove. Starting from a baseline of 900, how high will the CO2 level typically go in the kitchen while cooking with gas for 10 minutes - like frying 3 hamburgers ?? Edit: We’ve already decided against it, but I’m curious to know how bad the things actually are.

[@HomePerformance]

Should go doen, since you’re using the exhaust hood on high speed to pull all the gases outside. Right?

[@lindacgrace2973]

What happened to houseplants? NASA uses plants to recycle carbon dioxide and sustain oxygen levels, wouldn't that help in a house, too?

[@HomePerformance]

No, that’s a myth Linda- they don’t eat as much as you think

[@merlinthe]

A human exhales 500-1000g (1-2 pounds) of co2 a day. Your house plants would need to gain around this much weight every single day to offset one person full time at home. Plants were tested at the beginning of space age. Turns out you'd need a literal small rainforest in your home (a literal jungle) for plants to make a difference. Also, at night plants exhale co2, so if you hope that plants help with co2 levels in bedroom - they do the exact opposite. That is - they would do, if the carbon dioxide they processed were in any way significant. As for NASA - they use chemical scrubbing on their missions. Any plants on ISS are for research - testing how they behave in zero gravity, etc.

[@lindacgrace2973]

@@merlinthe Hi, Tomasz. When I made this suggestion, I assumed that the home would not be "air tight" like a space station or a submarine, but have tempered, filtered outdoor air ventilation. The plants absorb about 20% to 30% of the CO2 during the day, and enhance oxygen by about 10% to 15%. Houseplants can not (as you pointed out) substitute for fresh air ventilation; I did not mean to suggest that they would. I meant to suggest that they enhance the process and "lighten the load" for the rest of the ventilation system. Also, soil bacteria are actually more effective 'air scrubbers' than the plants, and help offset the plants nocturnal CO2 emissions. That's how greenhouses work. I disagree with your assessment that the effects are not significant. I think a small but measurable decrease in CO2 and another small but measurable increase in O2 is of significant benefit. But that is strictly a judgment call, so I understand why a non-gardener would make that call.

[@interactiveenterainment3978]

I’ve never heard anyone ask that question

[@donaldbakerakathedonaldaka5261]

Love seeing HavenIAQ on the screenshots!

[@av1204]

You should turn off your ERV for a day with some adult friends, don't use kids as a guinea pig, and then see what it goes up to. Proof the erv is worth the money :D

[@flashkan]

If you want proof, reefdudes and reefbum both installed hrvs i believe (Vermont and Canada). Their reef tanks saw notable increases in PH, which is directly aligned with ambient CO2 levels. Think reef dudes also built a co2 monitor into is tank monitoring system. I know of several others not on YT, all have had the same results.

[@Wildernut]

When CO2 is at 1000 in 30 years, what’s the solution?

[@HomePerformance]

We will be dumber, if that counts as a solution

[@alex-kv2bh]

Air things is trash u gotta replace batteries once every 3 days even with rechargeables

[@HomePerformance]

Rechargeables are trash u gotta get sum good bats brah

[@alex-kv2bh]

@HomePerformance which ones do you use and how long do they last? I tried multiple different brands and prices same result .I would love to start using my air things again

[@HomePerformance]

I use energizers, my Airthings needs new batts every 6-12 months.