n. (in mining) an explosive mixture of gases, usually containing a high proportion of methane, occasionally encountered in pockets underground. It can be distinguished from *blackdamp (chokedamp), which does not ignite.
(chokedamp) n. (in mining) the poisonous gas containing carbon dioxide, carbon monoxide, or other suffocating material, sometimes found in pockets in underground workings. Compare firedamp.... blackdamp
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