Why do you have to be concerned with CO? The gas is called a silent killer because it is essentially undetectable to the human senses. It is colorless, odorless, and tasteless - It can even go undetected by basic medical technology. A couple of minutes spent in a CO rich environment can cause someone to go unconscious and die.
Where/When do you have to be concerned about CO poisoning? CO is formed from incomplete burning of carbon containing fuels such as kerosene, propane, gasoline, wood, coal, etc. In the marine environment, this includes the gasoline engine, gasoline generator – diesel does form CO as well but not nearly as much as gasoline. Here on land, CO is formed by gas heat, woodstoves, furnaces, generators, automotive engines, etc. Any of these types of engines should be in a well ventilated area and the exhaust, especially (since that’s what contains the CO), should be well ventilated. CO poisoning occurs when any of the above are burned in or near an enclosed space.
How does CO poison? See that O in CO? That’s O as in Oxygen. CO binds to hemoglobin in your blood where oxygen normally does. In fact, CO has a higher affinity (greater attraction) to hemoglobin and will beat oxygen to the punch every time. This in turn robs the body of oxygen which is essential to life. Initial symptoms of low-level exposure present like the flu – dizziness, nausea, headache, fatigue. Increased exposure leads to vomiting, mental confusion, loss of muscular coordination, loss of consciousness, and death. Once symptoms start, the person should move out of the CO rich environment to a well-ventilated area and seek medical attention promptly. It is also advisable to call the fire department if you are unable to stop and/or find the source of CO and if you are unable to safely ventilate the area yourself.
Because CO binds to the blood in the same way that oxygen does, it will show up on noninvasive monitoring devices (pulse oximetry) as oxygen making someone seem perfectly oxygenated when, in fact, their body is deprived of oxygen. For this reason, if you have mild symptoms and the medical personnel are not aware of the possibility of CO poisoning, be sure to let them know so they can take a better health assessment and use the correct device to monitor the oxygen and CO in your blood.
What can you do to prevent CO poisoning? Always make sure that your engines, generators, furnaces, etc, are installed properly, maintained regularly according to manufacturer’s requirements and that they’re installed in a well-ventilated area. As far as woodstoves and fireplaces are concerned, make sure your chimney and flue is inspected and cleaned out on at least an annual basis to check for possible cracks, holes and clogs that could cause CO to pour into your house. Generators should be used outside of the house - not even in an attached garage with the door open. If using a generator, appliances should be plugged directly into the generator unless using a heavy duty, outdoor-rated extension cord that is rated (in watts or amps) at least equal to the sum of the connected appliance loads. Also, be sure to install a CO alarm - they work similarly to a smoke detector - in your home and boat if there isn't already one.