"Vass" wrote in message
...
Carbon Monoxide poisoning

these alarms you can buy appear to hang from the ceiling
as I understand it, carbon monoxide is heavier than air so surely would
sit on the ground
i.e. bit late if the gas reaches the ceiling
am I barking mad or have a point here?

You are thinking of carbon dioxide, which is about 2.5 times heavier than
air.

Colin Bignell