Industrial Minerals - Safety in Mining at the Andes Copper Mining Company's Property, Potrerillos, Chile

Safety work in mining at the Andes Copper Mining Company, Potrerillos, Chile, is divided into three parts: (1) accident prevention, (2) fire prevention and protection, and (3) silicosis prevention and control. In the company's operations a steady campaign has been waged to reduce accidents and silicosis, and to prevent fires. In the following pages the safety record for the past twelve years will be examined and the methods explained by which the accident rate was reduced. Table 1 contains yearly data pertaining to the scale of the mining operations and the accident record. Block caving is used for all ore production and the tonnage mined has averaged 30,000 short tons per day for the past seven years. Table 2 classifies 44 fatal accidents which have occurred since 1935. The leading causes of accidental death are transportation of ore and use of explosives, followed in order by persons falling, falls of ground, and by asphyxiation. In the case of serious accidents, however, the greatest cause is falls of ground, followed, in turn, by ore transportation, persons falling, explosives, and asphyxiation. Accident Prevention The improvement of the safety record was obtained by a combination of many factors. In surveying the results at Andes for the past twelve years, it is possible to select some features of the present operation which have contributed to the accident record. The most important of these are: (1) good staff planning, (2) good equipment, (3) an alert safety organization, and (4) education and selection of the workmen. GOOD STAFF PLANNING As a result of good staff planning, the mine has good working conditions, namely, good ventilation, moderate temperatures and humidity, and good lighting. These factors not only reduce accidents but also improve efficiency. In haulage work, accidents have been reduced by having traffic move in a forward direction only. The latter makes possible a one-man train crew. Trains are centrally dispatched from loading drifts which are interconnected by signal lights, so that when a train in a lateral drift is given permission to move into a main line drift, a red light signals in all other lateral drifts in that area. Good track is maintained, and safety niches are required at all switch throws. Since safety niches were provided there have been no fatal or serious accidents at such points. All main line haulage drifts are illuminated by electric lights. Haulage drifts are kept clean. Adequate clearance has been provided between cars and between cars and the sides of the haulage drifts. The 4 1/2 ton Cranby type cars are equipped with roller bearings, and the 10 ton loconlotives with trolley shoes instead of wheels. These two features are responsible for improved ore haulage conditions and contribute to greater efficiency and safety.