The cognitive costs of air pollution
> "Exposure to CO2 and VOCs at levels found in conventional office buildings was associated with lower cognitive scores than those associated with levels of these compounds found in a Green building." – Allen et al 2016. The effect seems to kick in at around 1,000 ppm of CO2.<p>The last time this came up I bought a CO2 meter for my office. I was quite surprised how often it went over 1,000. Outside air runs around 450.<p>I increased the duty cycle of the house fan, and open a window when it reaches 800. Right now I'm at 505.<p>Buying the meter was a really good investment.