A meeting room hit 2,143 ppm CO2, and the decisions got worse
Mike Bowler set a CO2 meter on a conference table and watched it climb past 2,000 ppm by the second hour. His claim: that is exactly when the expensive people in the room quietly get worse at deciding. The thread was not sure he was right.
Agile coach Mike Bowler clocked 2,143 ppm on a conference table. He cites Berkeley Lab: at 1,000 ppm, decision scores fell on six of nine measures; at 2,500, seven of nine dropped toward a range researchers called 'dysfunctional.'
The thread split. Submarine crews work in thousands of ppm with no measured deficit, and several readers flagged the post itself as AI-written. The real fight was whether CO2 is the cause or just the messenger.
The meter climbed past 2,000 while they talked
Mike Bowler's argument starts with one reading. Outdoor air sits near 400 ppm CO2; seal several people in a meeting room and it clears 1,000 ppm inside the first hour. On a conference table he clocked 2,143 ppm.
He stacks the research behind the number. Lawrence Berkeley National Laboratory found that at 1,000 ppm, performance fell on six of nine decision-making measures against a 600 ppm baseline; at 2,500 ppm, seven of nine dropped substantially, some into a range the researchers called "dysfunctional." A Harvard study logged declines in strategy, planning, and using information under pressure. Bowler's summary: "You are running your highest-stakes thinking in the environment least suited to it." His fix costs nothing. Open a window, then watch the second half of the meeting.
Submarines, canaries, and an AI-smell meter
The cheapest fix drew a practical add-on.
"look at your HVAC system, and there's probably an option to have the fan run all the time… your home's CO2 levels will drop substantially." — Rust project developer Josh Triplett
The firmest counter came with a citation.
"Submarines operate in the 1000s of PPM CO2 range and the sailors aboard generally do not experience any ill effects. This was tested and no deficits were found even at 15,000 PPM." — a commenter pointing to submarine-crew studies
Others questioned whether CO2 is even the villain.
"The building science community has not… come to the agreement that the CO2 itself is the cause of the cognitive decline. It could be the Canary in the coal mine." — a reader working from building-science literature
A loud faction distrusted the prose itself, reading it as machine-written.
"There needs to be a meter for the amount of AI writing in blogposts. Same physics, same climb, same afternoon fog." — an engineer at Google
Notice the split is not about the remedy: nobody argues against fresh air. It is about the mechanism. If CO2 is only a proxy for off-gassing plastics and solvents, the meter on your desk is reading the messenger, not the poison.
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This is the last story in the July 5, 2026 issue.
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