Danger of Carbon Dioxide

Burning or Oxidation:
When carbon dioxide occurs in large quantities, it is dangerous to health, because it interferes with normal breathing, lessening the escape of waste matter through the breath and preventing the access to the lungs of the oxygen necessary for life. Carbon dioxide is not poisonous, but it cuts off the supply of oxygen, just as water cuts it off from a drowning man.

Since every man, woman, and child constantly breathes forth carbon dioxide, the danger in overcrowded rooms is great, and proper ventilation is of vital importance.