The extreme carbon dioxide outburst at the Menzengraben potash mine 7 July 1953

Carbon dioxide is an asphyxiant and an irritant gas. An extreme outburst of carbon dioxide took place 7 July 1953 in a potash mine in the former East Germany. During 25 min, a large amount of CO2 was blown out of the mine shaft with great force. It was wind still and concentrated CO2 accumulated in a valley leading to multiple asphyxiation casualties. Based on a review of concentration-response relationships, the location of victims, and other information, it is concluded that concentrations of 10-30% carbon dioxide may have occurred 450 m from the point of release for at least 45 min. It is concluded that 11003900 tonnes of CO2 were blown out of the mine shaft, possibly with intensities around 4 tonnes/s. It is also concluded that the large majority of the gas escaped as a near-vertical high-velocity jet with only little loss of momentum due to impingement. The release was modelled using PHAST. Output from the model is inconsistent with the asphyxiation harm observed. The high-momentum release is predicted to disperse safely and never reach the ground. Carbon dioxide capture and storage (CCS) schemes will involve handling and transportation of unprecedented quantities of CO2. Case histories to date include sudden releases of CO2 of up to 50 tonnes only, far too small to provide a suitable empirical perspective on predicted hazard distances for CCS projects. The 1953 outburst contributes to filling this gap. (C) 2011 Elsevier Ltd. All rights reserved.