On Sat, 12 Dec 2020 15:35:21 -0800 (PST), John Walliker
wrote:

snip

I did some experiments with a CO detector that has a display reading parts per million.
It was a FireAngel CO9D. Close to a gas hob with all burners on and no deliberate
ventilation in the kitchen for about 20 minutes it eventually read about 10ppm.
Sister-in-law had been suffering bad headaches for some time and was concerned
that the woodburning stove in her kitchen was emitting CO, so she bought that
model of CO detector. There was a lot of CO in the house at times, but not from the
stove. It turned out that burning logs in an open fireplace was the cause. The
highest concentration - something like 450ppm I think - was found in one of the
bedrooms which had a fireplace whose flue was adjacent to that of the living-room
fireplace in the same chimney stack. Loose mortar in the brickwork allowed CO
from the wood fire in the living room to reach the bedroom.
So burning charcoal or wood can generate copious amounts of CO and it can get
into unexpected places. Fortunately the problem was fixed before anyone was
killed or injured.

Interesting and informative post. Thank you.

Cheers, T i m