Chas Tennis
G.O.A.T.
During the recent CA wildfires we had very bad air quality. Our advice - heard many times - was to "stay inside and close the doors and windows". While learning about smoke, HEPA air cleaners and other subjects, I found CO2 and its relation to building ventilation to be a very interesting topic. I know people that have complained of headaches for years - headaches have been associated with higher levels of CO2 in buildings and bedrooms.
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Background. CO2 exists in air at average levels of about 400 ppm. (parts per million)
[1% is 10,000 ppm]
Oxygen exists in air at 21% or 210,000 ppm.
en.wikipedia.org
Human breath contains roughly 4% or 40,000 ppm of CO2.
It seems likely that a second person, dog, etc. could make the CO2 levels much higher near someone that is sleeping.
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"Carbon Dioxide (CO2) Classification Guide
400ppm – Normal outdoor air level.
400 ~ 1000ppm – Typical value level indoors with good ventilation.
*Note: if CO2 levels are low when the building is sealed and occupied, check for over-ventilation (too much fresh air = energy wasted).
1,000ppm – the OSHA/ASHRAE recommended maximum level in a closed room. Considered maximum comfort level in many countries.
> 1,200ppm – Poor air quality – requires ventilation to the room.
2,000ppm – According to many studies this level of CO2 produces a significant increase in drowsiness, tiredness, headaches, lower levels of concentration, and an increased likelihood of spreading respiratory viruses like colds, etc. Proper ventilation at this level is needed - immediately. "
See other lists of CO2 levels vs effects.
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Why CO2 at around 2000 ppm may be associated with headaches is not clear to me.
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When smoke in the wildfires got heavy outside we used HEPA air cleaners so that we could stay in our house and breath.
Ventilation - Houses and rooms must be ventilated with a certain number of air exchanges per hour - this is a safety issue. The advice for wildfires is to stay inside and close the windows and doors.
CO2 levels can be used as a general indication of how well the house/room is being ventilation. 400 ppm is a lot of ventilation and, for example, 1200 ppm is poor ventilation. We got a CO2 sensor and learned about the possible headaches and CO2 level.
Our CO2 levels in closed bedrooms routinely went above 1000 ppm with two and even one person in the room. It could get higher.
Removing smoke from the air is one issue that HEPA air cleaners do well with. But ventilation requiring air with heavy smoke is also necessary.
If you have had headaches you might learn more about CO2 and headaches and consider getting a CO2 sensor to see your levels, especially when sleeping or hiding from smoke.
We monitoring our CO2 levels now.
---------------------------------------------------------------------------------------------------------------------
Background. CO2 exists in air at average levels of about 400 ppm. (parts per million)
[1% is 10,000 ppm]
Oxygen exists in air at 21% or 210,000 ppm.
Atmosphere of Earth - Wikipedia
Human breath contains roughly 4% or 40,000 ppm of CO2.
It seems likely that a second person, dog, etc. could make the CO2 levels much higher near someone that is sleeping.
--------------------------------------------------------------------------------------------------------
"Carbon Dioxide (CO2) Classification Guide
400ppm – Normal outdoor air level.
400 ~ 1000ppm – Typical value level indoors with good ventilation.
*Note: if CO2 levels are low when the building is sealed and occupied, check for over-ventilation (too much fresh air = energy wasted).
1,000ppm – the OSHA/ASHRAE recommended maximum level in a closed room. Considered maximum comfort level in many countries.
> 1,200ppm – Poor air quality – requires ventilation to the room.
2,000ppm – According to many studies this level of CO2 produces a significant increase in drowsiness, tiredness, headaches, lower levels of concentration, and an increased likelihood of spreading respiratory viruses like colds, etc. Proper ventilation at this level is needed - immediately. "
See other lists of CO2 levels vs effects.
----------------------------------------------------------------------------------------------------------------------------
Why CO2 at around 2000 ppm may be associated with headaches is not clear to me.
----------------------------------------------------------------------------------------------------------------------------
When smoke in the wildfires got heavy outside we used HEPA air cleaners so that we could stay in our house and breath.
Ventilation - Houses and rooms must be ventilated with a certain number of air exchanges per hour - this is a safety issue. The advice for wildfires is to stay inside and close the windows and doors.
CO2 levels can be used as a general indication of how well the house/room is being ventilation. 400 ppm is a lot of ventilation and, for example, 1200 ppm is poor ventilation. We got a CO2 sensor and learned about the possible headaches and CO2 level.
Our CO2 levels in closed bedrooms routinely went above 1000 ppm with two and even one person in the room. It could get higher.
Removing smoke from the air is one issue that HEPA air cleaners do well with. But ventilation requiring air with heavy smoke is also necessary.
If you have had headaches you might learn more about CO2 and headaches and consider getting a CO2 sensor to see your levels, especially when sleeping or hiding from smoke.
We monitoring our CO2 levels now.
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