The thesis shows the develoment of technology for controlling harsh climatic conditions, based on the example of the deep, hot coal mines in the eastern region of Ruhr coal mining district. For those mines the controlling of climatic difficulties was a question of survival. The influence factors impacting on of climatic conditions, which result from the progression of mining activities to greater depths, are shown. With the occurance of heat stress, and its measurement, the effect of heat stress on miners was recognized. Reliable risk based heat stress criteria were introduced by law and heat acclimatization strategies established. At the same time methods of dealing with the heat stress situation were developed in the Ruhr cosal mining district and elsewhere. Methods for controlling heat stress without climatisation are for instance: increasing of air quantity and velocity, optimization of mine working, using cold rock surroundings, prevention of heat transmission by isolation, avoiding absorption of vapour, reducing humidity in the air, pre-cooling of air by using the natural conditions at the surface and in the earth crust. A number of climatisation strategies for controlling heat stress conditions were developed, for instance: central and local refrigeration plants with heat exchange in surface radiators, cooling of compressed air and cold air machines, spray cooling, using ice as refrigerant medium, use of chilled service water and development of the hydropower concept in South Africa. Some empirically established methods of controlling heat stress are compared with later developed theory based foundations and conclusions drawn, why some of the methods were successful and others not. In an outlook suggestions are made, how to control increasing heat stress in the future, caused by greater depths in mines. Among others the question of micro-acclimatisation is analysed, because one can assume that only e few miners will work in the future coal mines. In these cases the total cooling of great areas of the mine working makes little sense, even more because the refrigeration requirements increase disproportionately with increasing depth. Higher face output causes higher heat transfer into the air, also by oxidation. Amongst others heat extraction from the coal seam prior to coal winning is one possible method combating heat flow into deep coal mine workings. Furthermore the face support, and the face equipment, can be used for heat isolation and as heat exchanger surface.