Article Text
Abstract
Background Human body responses to cold exposure by decreasing circulation in skin, arms and legs to prevent heat loss. Hands and feet are especially vulnerable to cooling as their own heat production is minimal and their heat balance depends almost totally on the heat transported by circulation. The thermal insulation of handwear is usually smaller than that in footwear, as manual performance is decreased by thick and clumsy handwear. As a result, cold hands are a common problem in outdoor work. Cooling of hands decreases manual performance and tactile sensitivity and increases the risk of accidents. This study aimed to quantify the problem of cold hands in Arctic open pit mines.
Methods The questionnaire study was carried out in four open pit mines in Russia, Finland, Sweden and Norway. Moreover, skin temperatures as well as thermal sensations were recorded in Kevitsa (Finland) and Aitik (Sweden) open pit mines among 14 male and 2 female mine workers with duties consisting mainly of outdoor work.
Results The questionnaire study (n = 1323) revealed that experienced cold problems were negligible at ambient temperatures above −10 °C. However, at −10 − −20°C, 25% of workers estimated that their prevailing thermal sensation was “cold”. Skin temperature measurements showed that finger skin temperatures were below 15°C (a threshold for sharp performance decrement) for 21% of the working time.
Conclusions The questionnaire study and skin temperature measurements suggest unequivocally that hands/fingers are so cold that manual performance is markedly decreased in more than 20% of workers/working time. Such a decrease in manual performance increases the risk of accidents. It should be noted that during the skin temperature measurements ambient temperature was never below −16°C. Improved cold protection should be directed to cold sensitive workers and tasks especially at ambient temperatures below −10°C.
This study was funded by Kolarctic ENPI CBC.
- Skin temperature
- manual performance
- mining