alt Hacker NewsI think it’s little appreciated that high CO2 levels cause cognitive impairment, and with the same amount of (often very poor) air exchange, higher outdoor concentrations can push indoor spaces to levels that cause impaired cognition and poor sleep. I’ve already been seeing this in my home, and will often open windows even when cold just to keep co2 levels reasonable. One solution that can help is an external air heat exchanger, which can exchange air with the outdoors without compromising your homes heating and cooling like an open window will do.
Noticeable cognitive impairment starts in the 700-1000ppm range, whereas it is very common for homes to reach 2000-3000ppm, especially when in a closed bedroom.
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>One solution that can help is an external air heat exchanger
I have one of those, it blows fresh air in through the bedroom and sucks it back out through the kitchen (loft house, this route prevents food smells from wafting into the bedroom). Aside from just feeling fresh all year, this system also prevents mosquitoes from entering in summer while still allowing air circulation, it automatically bypasses the exchanger at night to provide cool air and it has some pollen filters installed which helps with hay fever.
So great economic return and a bunch of upsides, but it does require space for the exchanger and the ducts throughout the house.
I have been monitoring for high CO2 for a few months now. I easily find myself in the 1000 - 1400 range for some time before I finally let some air in in winter.
I have not noticed significant cognitive impairment (not saying it did not happen)
My quality of sleep/life have greatly increased since installing an Energy Recovery Vent (ERV) — it exchanges outside/inside air through a membrane, which is about 60-80% efficient for both humidity and temperature re-capture (depending on fan speed).
[•] <https://en.wikipedia.org/wiki/Heat_recovery_ventilation#Ener...>
I use a Panasonic model — readily available from Big Box Retail (~$700 + $100 in vent/conduit) — which can do 20 - 60 cfm (in my 900 sqft home this can easiliy exchange the entire volume several times per day).
> higher outdoor concentrations can push indoor spaces to levels that cause impaired cognition
I am somewhat skeptical of this:
https://www.astralcodexten.com/p/eight-hundred-slightly-pois...
This is a meme on hacker news that's usually stated as a fact, but I'm not sure there's any robust evidence of cognitive impairment at <1000ppm
> I think it’s little appreciated that high CO2 levels cause cognitive impairment
Have you been telling representatives? Here's a letter I wrote to mine:
Really? Wow, I try to keep my place at 500-600, without that much effort.
Ok this sounds like BS, what kind of sensor is being used to get such readings? What do you use?
> high CO2 levels cause cognitive impairment
Sounds seriously unlikely. How would this work in practice, at the level of bodily functions?
> Noticeable cognitive impairment starts in the 700-1000ppm range
The US navy failed to detect such effects in submarine crew, even at much higher levels like 10,000 ppm.
Another reason to be skeptical is that exhaled breath is 4% CO2 (40,000 ppm!). Therefore a few thousand extra ppm in the inhaled air should not make much of a difference to the homeostasis mechanisms in our bodies.