In article , Rodney Blackall wrote:
In article ,
William Asher wrote:
Crackles McFarly wrote:
If someone had a LOT of money and we asked them to build a factory to
do nothing but pump out extremely gigantic amounts of CO2, would this
"speed up" or have any measurable effect on Global Warming ??
Note:I'm speaking of a factory that could produce a daily amount of
CO2 in nearly unimaginable amounts 24 hours a day non-stop.
[snip]
It would have an interesting, unexplored, side effect. To make all that CO2
would mean taking lots of O2 out of the atmosphere while putting lots of CO2
in; result=general suffocation and problem solved for humanity!

G'day Rodney,

Your comment got me wondering about "toxic" CO2 levels. A quick
google revealed the following recommendations from a lovely lot of
undefined acronyms -- whether they are authoritative or not, I don't
know. (Maybe one of the yanks reading this could translate please?)

quoting from http://www.inspect-ny.com/hazmat/CO2gashaz.htm
CO2 EXPOSURE LIMITS - Carbon dioxide exposure limits PEL and TLV set
by OSHA and NIOSH:

The U.S. EPA recommends a maximum concentration of Carbon dioxide CO2
of 1000 ppm (0.1%) for continuous exposure.

ASHRAE standard 62-1989 recommends an indoor air ventilation standard
of 20 cfm per person of outdoor air or a CO2 level which is below
1000ppm.

NIOSH recommends a maximum concentration of carbon dioxide of 10,000
ppm or 1% (for the workplace, for a 10-hr work shift with a ceiling of
3.0% or 30,000 ppm for any 10-minute period). These are the highest
threshold limit value (TLV) and permissible exposure limit (PEL)
assigned to any material.

OSHA permits a lowest oxygen concentration of 19.5% in the work place
for a full work-shift exposure. For the indoor workplace oxygen level
to reach this level (down from its normal 20.9% oxygen level in
outdoor air) by displacement of oxygen by CO2, the CO2 or carbon
dioxide level would have to reach 6.0% or 60,000 ppm.

It's worth understanding that a high CO2 problem in most circumstances
is most likely to be the corresponding reduction in available oxygen
in air rather than toxicity of CO2. As carbon dioxide levels climb
above a few percent, the concentration of oxygen in the air inhaled
begins to be affected. At 6% carbon dioxide, as we cited above, the
concentration of oxygen in air has decreased from 20.96 to 19.9%.
/quoting

At very least, there's clearly a problem with the copy editor at the
site -- "normal 20.9% oxygen" later down has become "20.96", which I
would have rounded to 21.0 rather than 20.9. Then there's that 19.5%
which seems to have become 19.9% in the end.

But I guess I'm just nitpicking trivia here and I assume the gross
recommendations are reliable, or at least numerically accurate.
So it looks like one would need three times the current level of CO2
in the atmosphere before even the EPA would perceive a problem from
this point of view, and that's a bloody lot!

Though, as you say, converting C to CO2 will actually extract O2 as
well as simply dilute it, so that would reduce the production target
for Cracker's factory to wipe us all out. Still a bloody lot though.

Cheers, Phred.

--
LID