Comment Re:This should have been a thing during the pandem (Score 1) 27
It isn't a thing in the US, unfortunately.
New buildings might have it integrated into their HVAC systems, and older construction might have it retrofitted, but the vast, vast majority of buildings in the US do not have CO2 monitoring. We have CO (monoxide) detectors, but that's an entirely different issue.
Another consideration is that for assessment of infectious disease risk, measurement of CO2 in indoor communal spaces needs to be distributed throughout, as opposed to having a single point of measurement that might only reflect the average air quality for HVAC control purposes. It's the same principle with temperature; multi-room dwellings such as offices will typically have thermostats distributed throughout the building to control each zone. When employees gather in a conference room and close the door, the CO2 level can skyrocket, easily hitting 1800 ppm without ventilation. I believe that CO2 concentrations should be as easy to access as temperature, and that the public could be educated about its meaning.
Regarding VOC versus CO2 monitoring, they both have their use cases, and which one is a more suitable to measure depends on what we are really wanting to know. VOC sensors will detect a wide array of compounds, but not all of them are indicative of human occupancy, whereas CO2 concentration is the direct product of respiratory activity (unless non-biological sources of CO2 are present, such as dry ice). So if we are interested in transmissibility of airborne diseases, I would pick CO2, since you could measure high VOC levels in the air of an unoccupied storage shed or basement that otherwise has virtually no risk of infectious disease. But if we wanted to measure if the air is clean and fresh--i.e., relatively free of pollutants, I pick VOC monitoring over CO2. Both are important because they are meaningful proxies for health risks, but they are proxies for different types of risk.