Geologists have long known that carbon dioxide may collect in underground workings, and in sufficient concentration may cause sudden loss of consciousness and death.1 It is known that the gas is likely to be expelled when the barometric pressure falls abruptly to low levels. Asphyxiation by carbon dioxide produced in the process of fermentation in breweries and during wine making has also been recorded. This paper presents the clinical findings in two men who survived asphyxiation by carbon dioxide, which had collected in a chamber at the head of a well.
The incident occurred on March 11, 1963, in London, while samples of water were being taken from a well. This procedure had been followed once weekly without incident for at least ten years. The barometric pressure had been falling for ten days until, on the day in question, it reached 981.2 millibars, which is low for the British
FREEDMAN A, SEVEL D. The Cerebro-ocular Effects of Carbon Dioxide Poisoning. Arch Ophthalmol. 1966;76(1):59-65. doi:10.1001/archopht.1966.03850010061013