Before I retired, I was a scientist with British Coal. There are many "damps" down a coal mine. The word comes from the German for gas (dampf). Each name comes from what the gas does or its origin rather than what it contains. Firedamp is methane gas because it burns. Blackdamp is carbon dioxide, because if there's enough present it will make you black out. Chokedamp is sulphur dioxide because of its smell and effect, stinkdamp is hydrogen sulphide (used in stinkbombs!) and afterdamp contains carbon dioxide and carbon monoxide among other things because it is the atmosphere after an explosion has taken place - it is poisonous as well as suffocating.

Cheers

Ray