Blackdamp (also known as stythe or choke damp) is an asphyxiant, reducing the available oxygen content of air to a level incapable of sustaining human or animal life. It is not a single gas but a mixture of unbreathable gases left after oxygen is removed from the air and typically consists of nitrogen, carbon dioxide and water vapour. The suffix d... Found on http://en.wikipedia.org/wiki/Blackdamp
(from the article `mine gas`) ...a few minutes. It is a product of the incomplete combustion of carbon and is formed in coal mines chiefly by the oxidation of coal, particularly ... Found on http://www.britannica.com/eb/a-z/b/74