The more carbon dioxide there is in a room, the worse your decisions might be! This is the result of a new study according to which our decision-making skills are greatly affected in closed rooms. The team from the State University of New York examined whether high CO2 exposure at school or at work could have a negative impact on our mental skills. The tests showed that the subjects' decision-making had already worsened at 1.000 ppm, compared to subjects in a room with 600 ppm CO2. (Typical outdoor concentration = ca. 380 ppm, indoors ca. 1.000, packed rooms = up to several thousand ppm.) Results were particularly impacted at 2,500 ppm.