Earth's Atmosphere, General Oxygen Requirements and Tolerances of Humans
(this is a repost)
For the record, Earth's general atmospheric composition (up to about 25km above sea level) is:
78% Nitrogen
21% Oxygen
1% Argon
0-7% Water Vapor (this varies greatly)
and assorted trace gases including (but not limited to):
ozone, carbon dioxide, neon, helium, methane, and hydrogen.
For the purposes of comparison, here are the basic oxygen requirements of humans (Jaffa, Asgard, and other alien species, please get your own data):
* 20.9-23.5 percent: Maximum permissible oxygen level. No effect.
* 20.9 percent: Percentage of oxygen found in normal air. No effect.
* 19.5 percent: Minimum permissible oxygen level. No effect.
* 15-19 percent: Decreased ability to work strenuously. May impair coordination and may induce early symptoms with individuals that have coronary, pulmonary, or circulatory problems.
* 12-15 percent: Respiration and pulse increase; impaired coordination, perception, and judgment occurs.
* 10-12 percent: Respiration further increases in rate and depth; poor judgment and bluish lips occur.
* 8-10 percent: Symptoms include mental failure, fainting, unconsciousness, an ash-colored-face, blue lips, nausea, and vomiting.
* 6-8 percent: 8 minutes - 100 percent fatal; 6 minutes - 50 percent fatal; 4-5 minutes - recovery with treatment.
* 4-6 percent: Coma in 40 seconds, convulsions, respiration ceases - death.
The toxic-to-humans levels of many commonly found gasses can be found here, in language that Carter would love you for. The data is intended for those working in manure pits, but it's still easily translatable into offworld hazards for SG-1.
The dangers of high concentrations of carbon dioxide can be read about here at the Canadian version of OSHA.
Remember, when in doubt, find a friendly geek and ask. Chances are, we'd be happy to explain it to you.
For the record, Earth's general atmospheric composition (up to about 25km above sea level) is:
78% Nitrogen
21% Oxygen
1% Argon
0-7% Water Vapor (this varies greatly)
and assorted trace gases including (but not limited to):
ozone, carbon dioxide, neon, helium, methane, and hydrogen.
For the purposes of comparison, here are the basic oxygen requirements of humans (Jaffa, Asgard, and other alien species, please get your own data):
* 20.9-23.5 percent: Maximum permissible oxygen level. No effect.
* 20.9 percent: Percentage of oxygen found in normal air. No effect.
* 19.5 percent: Minimum permissible oxygen level. No effect.
* 15-19 percent: Decreased ability to work strenuously. May impair coordination and may induce early symptoms with individuals that have coronary, pulmonary, or circulatory problems.
* 12-15 percent: Respiration and pulse increase; impaired coordination, perception, and judgment occurs.
* 10-12 percent: Respiration further increases in rate and depth; poor judgment and bluish lips occur.
* 8-10 percent: Symptoms include mental failure, fainting, unconsciousness, an ash-colored-face, blue lips, nausea, and vomiting.
* 6-8 percent: 8 minutes - 100 percent fatal; 6 minutes - 50 percent fatal; 4-5 minutes - recovery with treatment.
* 4-6 percent: Coma in 40 seconds, convulsions, respiration ceases - death.
The toxic-to-humans levels of many commonly found gasses can be found here, in language that Carter would love you for. The data is intended for those working in manure pits, but it's still easily translatable into offworld hazards for SG-1.
The dangers of high concentrations of carbon dioxide can be read about here at the Canadian version of OSHA.
Remember, when in doubt, find a friendly geek and ask. Chances are, we'd be happy to explain it to you.