Active man-cooling: a feasibility study. Final report on CEC Contract 7206/00/8/13

There is a small but increasing number of men in the British mining industry working in thermal conditions at or above those at which some form of remedial action could be considered to be required. Various approaches have been investigated with a view to avoiding curtailment of shift time, either by reducing the climatic conditions to below those limits, (e.g. by full-face refrigeration etc.) or by reducing the impact of these conditions on the individual, for example through manipulating the pattern of work in those climates. Individual personal cooling using some form of cooled garment has been employed successfully in a number of industries but, with the exception of the work of Hausman for the Belgian mining industry, has not been investigated for general mining work in climatic conditions appropriate to the moderately hot, humid conditions typical of British mining. Of the other personal cooling systems which have been employed, externally connected water-cooled garments appear to offer the best potential. In order to extend the options available to the industry in combatting the effects of hot working conditions on the workforce, the present project was therefore established to examine the feasibility of using such an approach in mining conditions.Initial experimentation showed a water-cooled coverall to be effective in reducing the physiological and subjective effects of working in a typical hot mining climate. However, studies of the operators of development machines (the initial target population) showed that, because of the time spent off the machine, a full coverage garment would not be suitable for mining conditions. An examination of various forms of limited coverage garment resulted in the selection of a waistcoat which, although less effective physiologically than the full coverall, produced some physiological benefit and a marked subjective benefit in subjects working in a typical hot mining climate.This pattern of slight physiological benefit coupled with substantial subjective improvement was repeated when the garment was tested in a simulated development task. This latter test was carried out using the prototype water chiller for use underground which had been developed during the course of the project.It was concluded that the use of externally connected water-cooled garments (active man-cooling) was a feasible addition to the design options available to the industry.