A study of exposure to cold in cold stores.
Effects of exposure to cold on skin-temperature and thermal sensations of eight experienced men wearing protective clothing, who were working normally in a cold store at sub-zero temperatures of about -27 degrees C, were studied to assess the feasibility of deriving work recovery routines from experiments conducted in the actual working environment. Although the variations in the responses to cold were such that insistence on a rigid pattern of working and recovery times would be unwise, results indicated that exposures of about 40% of the total time available would not make the risk of discomfort unacceptable, under the usual working conditions provided clothing rated at 5 to 6 togs was worn. Whilst individual reactions are important and there was, for example, an inverse relation between the age of the operative and the time spent in the cold, the results showed that the reactions of the working group are equally important. It was evident that the operatives worked together as a group which appeared to arrange the work loads to suit individual members of the group. The dry-bulb temperature of the air was an adequate index of the thermal environment, which was relatively constant so that the stress upon the operatives was assessed by time spent in the cold. Considerable individual variations in response to cold were evident; the hands and feet were found to be particularly vulnerable areas, and in general a significant fall in skin-temperature occurred whilst the operatives worked inside the store. At some time during the study, all operatives experienced discomfort from cold and there appeared to be a definite association between percentage incidence of discomfort and the time spent in the store. The current practice for the setting of work/recovery routines was questioned and suggestions were made following the results of the investigation.
Williamson
D K
DK
Department of Mechanical and Production Engineering, Polytechnic of the South Bank, London, UK.
Chrenko
F A
FA
Hamley
E J
EJ