RE/
At 800 ppm, for instance, the symptoms will start in
45 minutes and you'll be dead after 3 hours. At 1600
pps it starts in 20 minutes and you're dead 40 minutes
after that. At 6400 the pain starts in 2 minutes and
you fall down go boom die in 10-15.

This is why I've got CO monitors - plural - in my
house. This stuff is NOTHING to fool around with.

And, according to what I've heard, a nasty little add-on is that one's
hemogloben has a greater affinity for CO than it does for O2. Net result is
that once the stuff's bonded to enough hemogloben even if you get out to fresh
air or somebody drags you out you're still going to die because the O2 from the
fresh air can't get to the hemogloben.
--
PeteCresswell