[Conclusions from field studies of stress on miners caused by dry-hot climate conditions]

The physical strain of miners in hot salt mines based on analyses of heart-rates, deep body temperatures, and sweat-rates during real work was studied. Based on these results changes in the working conditions have been realized (air-conditioning of cabins or ambient air, technological changes, workpause-regimes). Cooling-wastes are not sufficient to reduce the thermal strain in hot-dry climate in normal work of salt-mines, independent of the principle of cooling. During fire-fighters work the physical work is the more dominating stressor in relation to the thermal strain.