Concentrations of carbon dioxide in a car

This Short Communication looks at carbon dioxide levels in an estate car. It consisted of a series of experiments involving: two adults and two children; two adults; and only a driver. Measurements were taken during a journey between two towns both while ventilation was on giving light forced air inflow, but the car’s interior air circulation off, and while both ventilation and air circulation were operating. In the case of the family of four with the interior air circulation on, the concentration of carbon dioxide was 3018 ppm after 25 min of driving. When there were two people in the vehicle, after 45 min this changed 4844 ppm. Finally, it reached 3576 ppm after 60 min with only the driver. The experiments were stopped if there was an observable decline in the driver’s concentration; after the car’s air circulation had been switched off, the symptoms disappeared within 5 min.