Roger Coppock wrote:
"Humans can survive 800 ppm CO2 easily--in fact most rush hour traffic
has that much C02 I've read."

Even for you, Ray, that is a very shallow statement.
Hint: "What make us 'human?' Can that survive 800
ppm CO2 easily?

I see your point--nobody wants to go outside only wearing a moonsuit.
But I was simply saying that humans can survive 800 ppm C02. It is
uncomfortable but survivable. Kind of like breathing fumes in a
crowded freeway.

As for toxicity, here is what OSHA says: "OSHA has indicated that the
lowest oxygen concentration for shift-long exposure is 19.5%,
corresponding to a carbon dioxide concentration well above 60 000 ppm
(6%). Carbon dioxide concentration, not oxygen concentration, is
limiting in such circumstances."

Not that I am advocating we go to the limit, but from 381 to 60k is a
ways to still go.

RL