Occupational safety and health

One of the main risks encountered by underground employees in deep level hard rock mining is exposure to high temperatures, which, coupled with strenuous work and dehydration, can result in varying degrees of heat disorders - from heat cramps to heat exhaustion, to heat collapse and heat stroke. Heat stroke is the most serious and dangerous, causing multiple organ failure, and can be fatal.

AngloGold Ashanti employs a heat stress management (HSM) programme to promote the health and well-being of its employees and to meet the requirements of legislation. HSM's focus is not solely on cooling underground working areas, but also on detecting and excluding individuals with heat intolerance by means of a screening procedure. Employees who are not heat intolerant then proceed underground for natural acclimatisation to occur, during the course of their first 10 shifts .

New recruits, employees returning from leave, and employees who have been off sick for seven days or more - and who work in physically demanding jobs at temperatures exceeding 27.5°C wet bulb - are required to undergo heat tolerance screening (HTS).

HTS involves a 30-minute step test, at a carefully controlled temperature (29.5º) in a climatic chamber. To make the test as representative as possible of underground physical work, employees are required to work at a constant rate in the climatic chamber by stepping on and off a bench, at a rate of 24 steps per minute, onto a 30.5 centimetre high bench. This stepping is intended to achieve a work output of 80 watts. Employees with an oral temperature below 37.6°C, at the end of the 30 minute period, are classified as 'potentially heat tolerant' and may proceed with natural acclimatisation underground. Individuals in excess of this temperature are considered to be 'grossly heat intolerant' and may not work in an environment which exceeds a wet bulb temperature of 27.5°C. The current rate of potentially heat intolerant employees is about 5% a month; this group is allowed a further two attempts to prove they are not heat intolerant, before they are considered a health risk and subsequently redeployed to alternative work areas.

An equally important aspect of HTS is education and awareness around the risks of heat-related disorders. This takes place in the waiting period prior to the actual heat tolerance test as well as during induction training on the mines. Employees need to know the importance of drinking water regularly to prevent dehydration (hourly water breaks of 500 millilitres are mandatory); the consequences of alcohol-induced dehydration; and the effects of pushing oneself over the limits. They also need to know the temperatures at which heat-related disorders may manifest and what precautions to take to minimise the risk.

The current HTS Centre, based at West Wits, is a large and somewhat run-down building, accommodating up to 100 employees at a time - an unwieldy number to effectively monitor correct and constant stepping, both of which are crucial to reliable statistics. A new building, catering for 20 at a time, is now to be erected in its place at a cost of R1 million ($160,000). This will result in an improvement in the quality of monitoring, which will also be conducted at fixed temperature and wind speed conditions. Construction of the centre is to take place over a 14-week period, and is expected to be operational by March 2005.