Finally, be aware that a smoke detector is not a carbon monoxide detector.  Although this fact might be obvious, it needs to be stated. Smoke alarms and CO detectors serve two different functions; one cannot be substituted for the other.

For more details on CO and what to do in the case of an emergency, see the Environmental Protection Agency's Sources of Indoor Air Pollution - Carbon Monoxide (CO) and the Carbon Monoxide Poisoning Web site's 10 Steps to Carbon Monoxide Safety.