Posted by June Cheah Nicholls on June 07, 2002 at 13:12:57:
Substance Information Sheet
Natural Gas - Methane, Ethane and Propane
Substance description:
Most natural gas, used as fuel in households, is a mixture of 85% methane, 9% ethane, 3% propane and 2% of other gases.
All of these substances are colorless gases with a characteristic unpleasant odor. The odor, however, is added to this mixture of otherwise odorless gases. Natural gas like other asphyxiant gases displace oxygen from the air and can cause asphyxia.
In industrial settings, these gases are also used in the manufacture of freezing agents, acetylene, ammonia, formaldehyde, and other chemicals. Workers should observe safety recommendations in order to avoid harmful exposures to these agents.
Please keep gas heaters, fuel gas containers and stoves serviced and your home heating system well ventilated to avoid high concentrations of these gases in your home environment.
Exposure to natural gas:
Methane, propane and butane displace oxygen from the air and can cause asphyxia when inhaled in large concentrations. Harmful effects of inhalation of natural gas depends on the amount of oxygen displaced from the air by these gases, the duration of the exposure, the time interval between the exposure and the medical assistance, and other factors.
http://www.toxicology.mc.vanderbilt.edu/Outreach/Poison/NATGAS.html