The linked article is fascinating. "They found that, on average, a typical participant’s cognitive scores dropped 21 percent with a 400 ppm increase in CO2."

The linked article is fascinating. "They found that, on average, a typical participant’s cognitive scores dropped 21 percent with a 400 ppm increase in CO2." If this result is reproducible, this is quite concerning considering: "In surveys of elementary school classrooms in California and Texas, average CO2 concentrations were above 1,000 ppm, a substantial proportion exceeded 2,000 ppm, and in 21% of Texas classrooms peak CO2 concentration exceeded 3,000 ppm."