Office air quality and productivity — what the evidence says

Harvard's COGfx studies measured cognitive performance under controlled changes in CO₂, ventilation and VOCs. Cognitive scores rose 11% when CO₂ moved from 1400 to 600 ppm, and a further 8% when VOCs were halved. The findings were replicated in office cohorts in Boston, Beijing and London.

Studies of mechanically ventilated offices consistently show 30–40% lower sick-day rates when outdoor air supply meets BS EN 16798-1 Category II. The marginal cost of the additional ventilation is a small fraction of the avoided absenteeism.

For a knowledge-work organisation, office air quality belongs in the same conversation as lighting and ergonomics. The ROI on demand-controlled ventilation and continuous monitoring is now well-established.