US Patent 7472554 Passenger environmental protection

The system includes a carbon dioxide sensor, a temperature sensor and a controller. The carbon dioxide sensor is in electrical communication with the controller and generates a carbon dioxide signal indicative of the carbon dioxide level contained in the air within the vehicle cabin. The temperature sensor is also in electrical communication with the controller and generates a temperature signal indicative of the temperature within the vehicle cabin. The controller is configured to initiate a safety precaution based on the carbon dioxide signal and the temperature signal.