NOIRS 1997 Abstracts of the National Occupational Injury Research Symposium 1997. Washington, DC: National Institute for Occupational Safety and Health, 1997 Oct; :31-32
Roof drilling and bolt installation in underground coal mines is labor intensive, repetitive, and exposes operators to many hazards which can result in accidents, both acute and cumulative in nature. One concern of mine safety officials is the number accidents occurring where the roof bolter operator is crushed by the powerful hydraulic drill boom. Another concern is the rising number of injuries due to cumulative trauma. A NIOSH team of researchers examined these problems with several goals in mind. The first was to identify the root causes of the acute trauma accidents and develop effective solutions that could be implemented promptly. The second goal was to examine the cumulative trauma exposure of roof bolter operators and develop recommendations aimed at reducing the risk of developing injuries. Finally, the team developed materials to educate the mining industry on human factors engineering principles with the intention of improving the design of roof bolting machines. The following steps were taken to investigate traumatic crushing injuries: interviewed roof bolter operators, analyzed video tapes of roof bolting operations, discussed issues with roof bolter manufacturers, analyzed mine accident data, and reviewed past research on roof bolter safety. The team determined that the goal of any intervention should focus on reducing the probability of a control being accidentally activated and reducing the chances of roof bolter operators placing themselves in hazardous positions around the machine. To achieve that goal, the team developed a list of solutions based on their analysis of the information collected. Some of the recommended solutions include the use of an operator-in-position interlock device, fixed barriers at pinch points, improved control guarding, and reduction in speed of the fast feed. Many of these ideas have already been implemented. In response to cumulative trauma exposure concerns, members of the project team conducted a study at an underground coal mine to examine roof bolter tasks that performed over time could put the operator at risk. For this study, three primary forms of data were collected and analyzed. Researchers analyzed 43 lost time incident descriptions, conducted a series of interviews with roof bolter operators, and observed operators performing roof bolting tasks. Common roof bolting activities were examined and issues identified as putting operators at risk of injury were discussed. Recommendations were developed which address the three elements which define a system: human, equipment, and environment. The recommendations can be used to increase worker awareness of risk factors, modify job procedures, improve existing equipment, and provide guidelines for future equipment design. Efforts to educate the mining industry have included the development of seminars on human factors design geared toward design engineers and mine safety personnel, the construction of mockups that demonstrate human factors principles, and the publication of a world-wide-web page devoted to human factors design issues associated with mobile underground mining equipment.