They are burying 3 folks from southern, NH today also. Propane heating system that had an exhaust vent obstructed by deep snow. I am shocked that people don't have, don't check, and don't respect the words odorless, colorless, tasteless.......or worse yet, remove or don't replace the batteries in non-hard wired alarms. That mall disaster was just plain lucky more were not injured or killed.
Years ago, it was dying in a car while out parking...engine idling.....leaky exhaust. Not many monoxide deaths in homes. Oil, propane, NG, coal....they will all kill you if exhaust isn't properly vented to atmosphere..