Carbon dioxide (CO2) and carbon monoxide (CO) sensors integrated into a building management system can be used to monitor pollutants and ensure the required amount of fresh air ventilation is reaching indoors. Based on sensor input, controllers can provide optimal ventilating, heating, and air conditioning by zone for occupant comfort and IAQ. They can also monitor and control natural ventilation dampers and provide smoke control during a fire to maintain breathable air zones for evacuation.