Humans spend about 90 percent of life indoors, which means nearly every breath we take happens inside a building. Yet while we scrutinize every ingredient in our food and care deeply about the purity of our oceans and forests, most of us overlook the quality of the air we breathe for the majority of our lives.
That indoor environment profoundly affects our health, cognition, and well- being. For years, carbon dioxide was seen only as a harmless indicator of poor ventilation. Now, we know it’s a harmful pollutant that dulls concentration and decision-making. Studies have shown measurable drops in focus and reasoning when CO₂ levels reach amounts common in everyday buildings. And it’s not just carbon dioxide. Pollutants such as dust, pollen, and volatile organic compounds have been proven to slow response times even in young, healthy office workers.
The reverse is also true: When indoor air quality improves, so do people. In a landmark 2016 study, Dr. Joseph Allen and colleagues at the Harvard TH Chan School of Public Health found that workers in “Green” buildings performed 61 percent better on cognitive tests . In “Green+” buildings — with both low volatile organic compounds and enhanced ventilation — their scores were more than double those of workers in conventional buildings, when tested for strategic thinking, crisis response, and information usage.