High carbon dioxide in the home

[Koolau]

IMO it's reasonable to be concerned about other contaminants in homes and other settings and CO2 is a relatively easy but imperfect way to measure indoor air quality.

Yeah, CO2 would give an indication of how tightly the home is sealed. CO2 will naturally build up in an enclosed space. The CO2 itself will not be an issue but might suggest other contaminants are also being concentrated. Of course, if there are no other actual contaminants to concentrate, it shouldn't matter.



You could look at it as a "good" thing if CO2 levels are higher inside than outside. It means all your efforts to plug leaks and seal windows and doors, etc., are w*rking. I'd never open my windows in the middle of winter because my CO2 levels were at 2000 or 3000ppm. I'd be celebrating how all my weather sealing and insulation was w*rking.



As mentioned earlier, the physiological effects of a few thousand ppm of CO2 should be minimal or non-existent.



If anyone has data that suggests otherwise, I'd like to see it.

 

[Gumby]

Here is a paper about submarine air quality specifications that that might shed some light on the topic:

https://www.irbnet.de/daten/iconda/CIB7571.pdf

As the paper mentions, the normal concentration limits are based on an 8 hour day. Submariners breathe the same air 24 hours a day.

 

[Walt34]

As mentioned earlier, the physiological effects of a few thousand ppm of CO2 should be minimal or non-existent.

There is that. With all the painting (latex paint only) that I've been doing in the basement DW insists that the fresh paint gives her a headache and she can't spend any time there until the smell goes away. I don't even smell it, maybe because I'm the one working with it.

But she's the one who wanted it painted in the first place. Some people you just can't please.

 

[Koolau]

Here is a paper about submarine air quality specifications that that might shed some light on the topic:

https://www.irbnet.de/daten/iconda/CIB7571.pdf

As the paper mentions, the normal concentration limits are based on an 8 hour day. Submariners breathe the same air 24 hours a day.

I agree with the issue of 24 hours/day vs 8 hours/day. Having said that, all the PELs (OSHA's Permissible Exposure Limits) have significant safety factors built in.

Oh, for the days reflected in the movie "Das Boot." One of the best movies ever made about fighting in a submarine. I could just smell the mixture of sweat, rotting garbage, sulfur dioxide and diesel fumes. After that type of life, I'd think today's modern nukes would be a pleasure cruise (air-quality wise.) YMMV

 

[Gumby]

I agree with the issue of 24 hours/day vs 8 hours/day. Having said that, all the PELs (OSHA's Permissible Exposure Limits) have significant safety factors built in.

Oh, for the days reflected in the movie "Das Boot." One of the best movies ever made about fighting in a submarine. I could just smell the mixture of sweat, rotting garbage, sulfur dioxide and diesel fumes. After that type of life, I'd think today's modern nukes would be a pleasure cruise (air-quality wise.) YMMV

This is the catalog of smells on a modern US Navy nuclear submarine

1. Monoethanolamine, which smells like dead fish
2. Cigarette smoke
3. Diesel fuel and exhaust fumes (even nuclear subs have an emergency diesel engine)
4. Lubricating oil
5. Human waste from 120 men in what are called, euphemistically, the "sanitary tanks"
6. Ozone
7. 120 young guys, many of them mere teenagers, whose ideas of personal hygiene are not mainstream.
8. Cooking residue and waste (garbage).
9. Whatever weird stuff collects in the bilges.

When I came home from sea, the young wife would make me strip on the porch. Not because she was hot for me, but because I smelled so bad.

PS - I agree about Das Boot. It is my favorite submarine movie

 

[Koolau]

PS - I agree about Das Boot. It is my favorite submarine movie

You know it's a good movie when they can get you rooting for the German Sub crew!

 

[NXR7]

I worked in the basement of a corporate headquarters.The air circulation was poor and people were feeling tired and falling asleep. EH&S did a survey and found the CO2 levels were approaching 750 PPM, which was below OSHA limits.

But because there were people with symptoms and that causes sick leave and similar problems they replaced the thermostats with ones what had CO2 detectors. When the CO2 went above 500 PPM the air handlers in the ceiling in that area opened full and blew cold air throughout the room.

Of course, a few of us knew that so we'd wander over to another area, stand next to the support with the thermostat/CO2 detectors and assure we were exhaling directly on them. We could see the air handlers open up so we'd wander back to our area and a few minutes later people would start complaining about how cold it was getting.

 

[woodguy00]

The ideal answer, although not cheap, is a ventilating dehumidifier ducted into the supply side of your ductwork. It will dehumidify year round but particularly in the shoulder months when a/c isn’t running. The unit can be controlled by a CO2 monitor to bring in fresh air, through the dehumidifier, to improve the air quality. For example you can set the controls for the dehumidifier to run when indoor humidity is above 50% and to bring in fresh air any time CO2 hits 750ppm. These are the best answer in the humid south for tight, high performance homes. One major brand is Santa Fe who also produce units for some of the big name a/c brands. Units run around $1500 plus the cost of installation, controls and the additional ducting and inlet needed.
,

 

[Koolau]

I worked in the basement of a corporate headquarters.The air circulation was poor and people were feeling tired and falling asleep. EH&S did a survey and found the CO2 levels were approaching 750 PPM, which was below OSHA limits.

But because there were people with symptoms and that causes sick leave and similar problems they replaced the thermostats with ones what had CO2 detectors. When the CO2 went above 500 PPM the air handlers in the ceiling in that area opened full and blew cold air throughout the room.

Of course, a few of us knew that so we'd wander over to another area, stand next to the support with the thermostat/CO2 detectors and assure we were exhaling directly on them. We could see the air handlers open up so we'd wander back to our area and a few minutes later people would start complaining about how cold it was getting.

Because of the business I was in at Megacorp, I was privy to a number of arcane studies that indicated people's reactions to "recognition of" or "testing of" certain environmental "insults." Example.

One study showed that w*rk output INCREASED (whether light was increased OR decreased) when empl*yees saw their light levels being tested by management.

In the case of 500 vs 750 ppm CO2 - there IS no difference from a physiological standpoint. As pointed out above: When you're producing 40,000 ppm of CO2 with every breath 250 ppm is insignificant.

What's more likely in such a situation is that folks get sleepy in the afternoon. It happens to coincide with 50 people (or whatever) in a room building up the CO2 levels marginally. DEAL with it (though it doesn't need dealt with) and the cold temperature wakes people up and makes them feel better. (Our management must CARE about us!)

 

[boatfishandnature]

No matter what the weather, we always have one window cracked about 1/4 inch for fresh air year round. It's in the back part of the house, in a bathroom, so doesn't really affect the thermostat for heat or AC.
But we do not live in a very humid area.
We also have two CO2 monitor/alarms in the house.

Same here! If your house is totally closed, you have more dangerous things to worry about than CO2 - COVID, cold and flu viruses, anything that you spray, volatile substances from paint, plastics, etc. Leave one small window open. Your air conditioners will work a little harder, but your health is worth it. Add a dehumidifier (MEACO makes some great ones) on very humid days.

 

[Lewis Clark]

This is the catalog of smells on a modern US Navy nuclear submarine

1. Monoethanolamine, which smells like dead fish
2. Cigarette smoke
3. Diesel fuel and exhaust fumes (even nuclear subs have an emergency diesel engine)
4. Lubricating oil
5. Human waste from 120 men in what are called, euphemistically, the "sanitary tanks"
6. Ozone
7. 120 young guys, many of them mere teenagers, whose ideas of personal hygiene are not mainstream.
8. Cooking residue and waste (garbage).
9. Whatever weird stuff collects in the bilges.

When I came home from sea, the young wife would make me strip on the porch. Not because she was hot for me, but because I smelled so bad.

PS - I agree about Das Boot. It is my favorite submarine movie

Yes. My seabag of clothing was not allowed in the house until it went directly into the washing machine along with a cup of ammonia to remove the "submarine smell".

There were a couple of times when we ran the emergency diesel generator so long that the exhaust turned the air inside the submarine blue. You know it's bad when people are wanting to wear the emergency air breathing system masks for hours at a time.

After ventilating the submarine with fresh surface air, the air inside the submarine smelled noticeably better.

Ahhh ... the good old days ...

+ 2 for Das Boot. I've seen it both in English and also in German with English subtitles. Oddly, I enjoyed it more with the subtitles.

 

[ERD50]

....
PS - I agree about Das Boot. It is my favorite submarine movie

...
+ 2 for Das Boot. I've seen it both in English and also in German with English subtitles. Oddly, I enjoyed it more with the subtitles.

Good to hear that someone 'in the know' appreciated that movie. I've watched it a couple times over the years, some of those scenes really give me the creeps, but I may be due for a re-watch.

I think the 2nd time I watched it was with my son when he was a HS freshman and in German class. I had forgotten about some of the crude stuff, and was a little embarrassed at times. His teacher said something like "Oh, so you learned a few new words then!".

-ERD50

 

[jim584672]

If your CO2 is that high you should also test for Radon which can get trapped by a tight house.

 

[CaptTom]

The pollution agencies love sounding alarms based on the presence of trace amounts of whatever chemical makes the mice unhappy when they are exposed to high concentrations. Sure, CO2 is dangerous in high concentrations. So is water.

While I agree that measuring CO2 can be a useful proxy for other potential contaminants, I share the skepticism over this new fad.

When I first saw a post about C02 levels (probably here) I assumed it was a typo and they meant CO. Nope. Measuring CO2 is actually a thing now.

The whole idea seems kinda scammy. All this talk in the news about how CO2 affects our climate. CO2 is the new boogeyman. It's evil and must be banished! Here, buy my monitoring product!

Lots of good posts above with facts, figures and anecdotes to put this fad in context. Thanks all!

 

[eytonxav]

I cannot recall specifically what the CO2 levels were, but they were relatively high. What I do recall is that I suffered from terrible headaches when we were submerged and that they were alleviated by ventilating the boat. As you know, however, there are a variety of other atmospheric contaminants (including most significantly CO) on the boat, so it could have been something else entirely.

Is the atmospheric pressure inside a submarine greater than 1 atm? If it is, I would guess that could be a factor for some getting headaches.

 

[Gumby]

Is the atmospheric pressure inside a submarine greater than 1 atm? If it is, I would guess that could be a factor for some getting headaches.

It is usually right around 14.7 psi, but it can vary. Occasionally, if you go too long between ventilating, the pressure can be higher, which is why you always need to use care when opening the hatch when you first surface. There is a catch on the hatch rim so that you can crack it slightly to equalize the pressure without being flung out of the boat by a hatch blown open.

And sometimes, air pressure can be lower. The most drastic is when you are snorkeling at periscope depth and the head valve on the induction mast (that's how air is drawn into the boat when you ventilate or snorkel) is momentarily covered by a wave. It senses the water and immediately slams shut to prevent flooding, meaning no more air gets into the boat. But the diesel engine draws its air supply from the interior of the boat and exhausts overboard. So it immediately draws a vacuum in the boat until it trips on low intake pressure. When that happens, it feels like your eyeballs are about to pop out of your head.

 

[Koolau]

While I agree that measuring CO2 can be a useful proxy for other potential contaminants, I share the skepticism over this new fad.

When I first saw a post about C02 levels (probably here) I assumed it was a typo and they meant CO. Nope. Measuring CO2 is actually a thing now.

The whole idea seems kinda scammy. All this talk in the news about how CO2 affects our climate. CO2 is the new boogeyman. It's evil and must be banished! Here, buy my monitoring product!

Lots of good posts above with facts, figures and anecdotes to put this fad in context. Thanks all!

Yeah, I agree.



My first thought when some talking head mentions CO2: Hold your breath and quit talking. That'll lower the CO2!