Do Deep Mechanized Miners Get Better at Working in the Heat With Age?

Publication Type: 
Conference Proceedings

Presented at the 2014 WSN Mining Health and Safety Conference

Glen Kenny
Full Professor and University Research Chair
University of Ottawa

Current workplace heat safety guidelines are primarily based on research performed on young, healthy individuals, placing aging workers and those with chronic health conditions (e.g. diabetes) at risk. The aging process in humans is a complex yet natural occurrence that brings about many physical changes that can impact a worker’s ability to safely carry out physically demanding tasks especially when performed in the heat. Aging causes changes in the body’s normal response to work in the heat as the ability to dissipate heat and maintain core temperature becomes compromised. Recent findings demonstrate that decrements in whole-body heat loss capacity occur as early as the age of 40 and decline to a greater extent with advancing age. This impairment is exacerbated in individuals with chronic health conditions such as Type 2 diabetes. This means that older workers and those with chronic health conditions may be at a greater risk of suffering from a heat-related injury or death. In this presentation, we will review how ageing affects the body’s ability to dissipate heat as measured by a direct calorimeter (a device for making extremely accurate measurements about the heat emitted by the human body). Further, we will examine how new scientific knowledge is being used to develop age specific heat stress exposure limits for levels of air temperature, relative humidity, work intensity, and clothing representative of mining conditions.