 Bgrigg wrote: |
Other than Al Gore? ![Whistling [:-^]](/emoticons/icon_smile_whistling.gif) CO² is what we breathe out, so I wouldn't worry. It's Carbon Monoxide (CO) that is the killer. CO² just smells bad! |
|
saturating the air with anything is going to be bad for you. adding CO2, or nitrogen or anything no matter how nontoxic is still going to displace oxygen.
from wikipedia:
Pollution and toxicity
Carbon dioxide content in fresh air varies and is between 0.03% (300 ppm) and 0.06% (600 ppm), depending on location and in exhaled air approximately 4.5%. When inhaled in high concentrations (greater than 5% by volume), it is immediately dangerous to the life and health of humans and other animals. The current threshold limit value (TLV) or maximum level that is considered safe for healthy adults for an 8-hour work day is 0.5% (5000 ppm). The maximum safe level for infants, children, the elderly and individuals with cardio-pulmonary health issues would be significantly less.
These figures are valid for carbon dioxide supplied in "pure" form. In indoor spaces occupied by humans the carbon dioxide concentration will also reach a level higher than in pure outdoor air. Concentrations higher than 1000 ppm will cause discomfort in more than 20% of occupants, and the discomfort will increase with increasing CO2 concentration. The discomfort will be caused by various gases coming from human respiration and perspiration, and not by CO2 itself. At 2000 ppm will the majority of occupants feel a significant degree of discomfort, and many will develop nausea and headache. The CO2 concentration between 300 and 2500 ppm is used as an indicator of indoor air quality in spaces polluted by human occupation.
Acute carbon dioxide toxicity is sometimes known as Choke damp, an old mining industry term, and was the cause of death at Lake Nyos in Cameroon, where an upwelling of CO2-laden lake water in 1986 covered a wide area in a blanket of the gas, killing nearly 2000. The lowering of carbon dioxide in the atmosphere is largely due to absorption by plants, which convert it to sugars through photosynthesis. Phytoplankton photosynthesis absorbs dissolved CO2 in the upper ocean and thereby promotes the absorption of CO2 from the atmosphere.[5]
Carbon dioxide is a surrogate for indoor pollutants that may cause occupants to grow drowsy, get headaches, or function at lower activity levels. To eliminate most Indoor Air QualityNIOSH considers that indoor air concentrations of carbon dioxide that exceed 1000 ppm are a marker suggesting inadequate ventilation (1,000 ppm equals 0.1%). ASHRAE recommends that CO2 levels not exceed 1000 ppm inside a space. OSHA limits carbon dioxide concentration in the workplace to 0.5% for prolonged periods. The U.S. National Institute for Occupational Safety and Health limits brief exposures (up to ten minutes) to 3% and considers concentrations exceeding 4% as "immediately dangerous to life and health." People who breathe 5% carbon dioxide for more than half an hour show signs of acute hypercapnia, while breathing 7–10% carbon dioxide can produce unconsciousness in only a few minutes. Carbon dioxide, either as a gas or as dry ice, should be handled only in well-ventilated areas. complaints, total indoor carbon dioxide must be reduced to below 600 ppm.