Our smoke and heat devices call the fire department.
Since you own a smoke detector, you obviously realize what an important safety measure this device is. That’s good. Smoke detectors are highly effective in preventing loss of life and property. However, there are differences between the "stand alone" or battery-operated smoke detector you would buy at your local hardware store and one installed as part of your home security system.

"Stand alone" detectors are not connected to other detectors or warning devices. A smoke detector connected to your security system offers more protection because it is monitored by a central station. If fire strikes, the detector sets off an alarm and sends a signal to the control panel. The control panel dials the central station, where the operator notifies the fire department. Only central station monitored smoke detectors provide automatic notification of authorities when you or your family are asleep, not at home or unable to get to the phone.

CO2 Detectors
What is Carbon Monoxide and How Can it Harm Consumers?
Carbon monoxide (CO) is an odorless, colorless, tasteless and highly toxic gas that is produced when fuels such as wood, gasoline, charcoal and oil are burned with insufficient air. The majority of residential and commercial fatalities caused from these fuels come from heating systems, engine powered tools and charcoal grills. Carbon monoxide is harmful when inhaled because it displaces oxygen in the blood and deprives the heart, brain and other vital organs of oxygen. Large amounts of CO can overcome a person in minutes without warning—causing them to lose consciousness and suffocate.