chokedamp

noun

1. (uncountable, usually)A damp consisting chiefly of carbon dioxide, so called for its ability to asphyxiate.

   “"Now, when you described the Wigan coal explosion last month, could you not have gone down and helped those people, in spite of the choke-damp?" "I did." "You never said so." "There was nothing worth bucking about." "I didn't know." She looked at me with rather more interest.”