On Fri, 31 Oct 2008 22:55:58 +0000, Mark Rand
wrote:


Further to your comments, 40 years ago the rooms may have been far more
"leaky" than they tend to be nowadays.

5% CO2 will cause unconsciousness in some individuals and 10% will eventually
cause unconsciousness and death in all individuals.

I speak as one who lost consciousness due to an environment that was later
measured with a Dreager tester to have 5% CO2. Since that environment happened
to be a very well sealed full-face crash helmet in a rain storm, I was
extremely lucky to get away with only a broken leg and a written off
motorcycle...


Mark Rand
RTFM

I'll bet you meant Draeger, as in Draeger rebreather, rather than
Dreager.

Luck counts, both ways. Glad you had good luck that day.