Mining Topic: Interface and Job Design
What is the health and safety problem?
Equipment design refers not only to overall design specifications but also to design of the components and interfaces used by mine workers to do their jobs and to maintain the equipment. For workers to perform in an effective, efficient manner without injury, it is critical that the cognitive and physical requirements be carefully considered and within human capabilities, limitations, and capacities. Careful consideration must be given to the workload and psychosocial aspects of the work.
The types of injuries related to equipment design run the full range from acute such as falls and crushing accidents to repetitive strain such as whole body vibration and overexertion. Some injuries are fatigue related but have not been well-documented or as easy to assess, detect, or predict. The root causes of injuries can often be brought back to the design of both jobs and equipment.
What is the extent of the problem?
Both underground and surface mining operations as well as preparation plants use a variety of production and maintenance equipment, conveyors, and monitoring equipment. The interface between the operator and the equipment is critical to safe and effective operation. Mine workers are sometimes remotely located to their equipment, the equipment is large, and the visibility of other workers is reduced. Larger equipment may also increase the physical demands during maintenance.
How is OMSHR addressing the problem?
Much work has been accomplished in the area of seating and whole body vibration effects on health and safety. The Office of Mine Safety and Health Research (OMSHR) is developing and conducting testing in the areas of proximity warning systems to provide operators with the knowledge of how close they are to hazards in and around equipment so they can make better decisions for their own health and safety. On a broader level, an audit program is currently underway which will help mines to evaluate their equipment and jobs to reduce musculoskeletal injuries.
OMSHR is also conducting tests in the area of controls design to help limit acute injuries caused by operators inadvertently activating the incorrect control or the correct control in the wrong direction. Current research is focused on roof bolting equipment for underground mining but the principles and concepts will be applicable to the design of all equipment.
What are the significant findings?
Research conducted at OMSHR led to the NIOSH-developed shuttle car seat which was shown to have reduced major jarring and jolting better than any other commercially available seat. The leading manufacturer of shuttle car equipment in the U.S. provides the NIOSH seat as an option in its equipment list.
Training and assessment programs have resulted in interventions in the mining industry when researchers followed up with the mines that implemented the programs. These interventions were based on the principles and guidelines given in the OMSHR-developed training and demonstrations products.
A controls design study showed the importance of standardized controls when shape coding and location coding are used. Also, a precursor for controls that have been known to be involved in severe injury and death can be effectively coded with a feedback mechanism to alert the operator of the pending motion.
What are the next steps?
Research into the presentation of data from these new technology devices is critical to their use, interpretation, and acceptability. The final evaluation of the controls research will be conducted in the field to determine its usefulness and practicality. Providing guidelines and principles to the mining industry to evaluate the industry’s technology needs and the best design criteria for purchases is needed.
Noteworthy Publications & Products
- A Method for Evaluating System Interactions in a Dynamic Work Environment (1997-01)
Discusses a methodology to evaluate the causes of mishaps to develop recommendations to enhance safety. A specific case involves implementation of remotely controlled equipment in extended cut mining.
- Continuous Mining: A Pilot Study of the Role of Visual Attention Locations and Work Position in Underground Coal Mines (2009-08)
The purpose of this study was to perfect a method of gathering information on work positions and Visual Attention Locations needed by operators during the cutting phase and while the continuous miner trams to a new location.
- Ergonomic and Existing Seat Designs Compared on Underground Mine Haulage Vehicles (2003-10)
NIOSH researchers conducted a study to compare seat designs on underground coal mine haulage vehicles.
- Ergonomics and Risk Factor Awareness Training for Miners (2008-07)
This training will increase awareness of risk factors and encourage miners to take action to report and reduce their exposures to risk factors.
- Ergonomics: Beyond Compliance (2007-02)
Many mines are realizing that the only way to tackle cumulative injuries is to better understand those injuries and their root causes. The benefits of a formalized approach to reducing these injuries along with examples is presented.
- Evaluation of Systems to Monitor Blind Areas Behind Trucks Used in Road Construction and Maintenance: Phase 1 (2003-02)
NIOSH is evaluating methods to decrease accidents including one that uses devices that assist equipment operators in monitoring blind areas around the equipment to prevent collisions with workers on foot or other objects.
- Practical Demonstrations of Ergonomic Principles (2011-07)
This document consists of a series of demonstrations designed to complement training on ergonomic principles.
- Predicting System Interactions in the Design Process (1999-09)
Almost every process has a predecessor, and studying the predecessor helps to define needs and shortcomings to be addressed. This paper illustrates how such an approach was used to assess remote machine operation in underground coal mines.
- Preventing Equipment Related Injuries in Underground U.S. Coal Mines (2007-10)
The five top priority hazards associated with underground coal mining equipment have been identified and information about potential contributing factors and controls collated.
- Self-Reported Musculoskeletal Symptoms Among Operators of Heavy Construction Equipment (2003-08)
This study assessed the adequacy of cab design and determined the percentage of musculoskeletal symptoms among operators of heavy construction equipment.