Carbon Monoxide is a silent odorless gas that can kill you very quickly as within 30 minutes to an hour or even less depending on the amount of carbon monoxide that is in the room or house you're in.
You should always have working carbon monoxide detectors in your home so that you can be alerted to any carbon monoxide that is in your home and if there is any carbon monoxide detected in your home you should open windows and doors to allow fresh air in and get outside.
Make sure gas vents are clear and unobstructed and are properly vented to the outside.
Common signs of carbon monoxide poisoning are shortness of breath, weakness, confusion, headache, nausea and dizziness.
If you think you or someone has carbon monoxide poisoning get outside and call 911 because carbon monoxide poisoning can be deadly real quick.