Carbon monoxide exposure in the last 24 hours
How can I tell?
If you have had a higher than normal level of carbon
monoxide exposure then you have been poisoned, it is a question of how severe it is.
If you think you may have been exposed during the last 24 hours then take IMMEDIATE action - DO NOT DELAY:
- Get fresh air immediately - open doors and windows, turn off combustion appliances, and
leave the building.
- Call 911.
- Do a head count to make sure people and pets are out of the building.
- Go to an emergency room and let them know you suspect carbon monoxide exposure and
poisoning. Specifically ask to have a blood test for
carbon monoxide (this is only a meaningful test if done within a few hours after exposure).
Even if you answered "No" to all of the above, it is still possible you may have had low level carbon monoxide
exposure.
To be safe, even if you think there is the smallest chance you or anyone else at your location has had
carbon monoxide exposure:
- Open windows to allow fresh air flow within the building.
- Get fresh air immediately.
- For very mild poisoning, fresh air may be all that is needed. As soon as a person breathes fresh air the
levels of carbon monoxide in the blood will begin to decrease and return to normal levels.
- Call the fire department. Most will come to your location and test for safe levels of carbon monoxide in the home or building. Some may
even do a quick check for anything that looks unusual.
- Buy and install a carbon monoxide detector. Check your premises for anything that looks
out-of-the-ordinary.
- Arrange to have all fuel burning appliances inspected and serviced as soon as possible.
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of Carbon monoxide exposure in the last 24 hours. How
can I tell?
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"After turning off the appliance that caused carbon monoxide, how long does it remain in the home?"
There is no one answer.
Carbon monoxide will remain in the home as long as the windows and doors stay closed and that the forced air heating/cooling system (if there is one) stays off.
Once the doors and windows are opened and fresh air can circulate the carbon monoxide will dissipate quickly but how quickly will depend on the airflow.
If there's an outdoor breeze the carbon monoxide should leave the building within 15 minutes or so.
Carbon monoxide gas has a very similar density to air and like air, will travel where the air flows.