I kinda think people spend too much effort on trying to track CO2, and not enough on improving amelioration of it. My take is that everyone in a small poorly ventilated apartment should just assume they don’t get enough fresh air and spend the money they would have spent on a CO2 monitor on a small in-window heat-recovery ventilator with fan and air filter. Of course, this would require such a product being able to be purchased… and society itself is falling short on that front.
Here’s the closest that amazon comes to offering this:
https://www.amazon.com/TOSOT-Ventilation-Conditioner-Residential-Applications/dp/B0DZCN1MQT
I kinda think people spend too much effort on trying to track CO2, and not enough on improving amelioration of it. My take is that everyone in a small poorly ventilated apartment should just assume they don’t get enough fresh air and spend the money they would have spent on a CO2 monitor on a small in-window heat-recovery ventilator with fan and air filter. Of course, this would require such a product being able to be purchased… and society itself is falling short on that front. Here’s the closest that amazon comes to offering this: https://www.amazon.com/TOSOT-Ventilation-Conditioner-Residential-Applications/dp/B0DZCN1MQT
Which should ideally be crossed with this: https://www.amazon.com/Weiworld-Ventilation-Provides-Circulation-Basements/dp/B0DYT5R9YC
And made easy to put in a window like this: https://www.amazon.com/BLACK-DECKER-Twin-Window-Fan/dp/B0CNHB7WJ4
Such a thing is totally possible to be produced at acceptable quality for a price point of less than $200 USD.