Research paper

Ergonomics in the Mining: A Case Control Study Safety in the Mining Industry.

Nick Bradley

University of Wisconsin at Whitewater

Principles of Epidemiology


            The mining industry is important to the economy of many countries and the products that are created are used in everyday life.  Although important to our way of life, the mining industry has proved to be a very dangerous industry.  In this study, the investigator examined the safety practices of the mining industry to discover a correlation between the safe mining practices of the mining company and the rate of injuries.  The profitability of the mine was also examined to determine the extent of how much was invested into safe working practices.  The study attempted to show that an investment into safety can increase profitability by decreasing injuries and the direct and indirect costs that are associated with those injuries.  A questionnaire was given to numerous employees in the mining industry to determine their company’s safety practices and the rate of injuries within the company.


The mining industry is an important component of the economy of many countries because of the utilization of coal, metal, and non-metal minerals in those countries.   The use of these minerals is extensive and includes many products that we use in everyday life.  Because of its importance mining is often very profitable, but there are often many risks faced by those that work in the industry.  According to the Mine Safety and Health Administration (MSHA, 2012) there were 1,871 surface and underground coal mines which employed 137,650 worker and 12,222 metal or non-metal mines which had a workforce of 250,228.  This is a total of 14,093 active mines and 387,878 workers that were engaged in mining operations in the areas of production, preparation, processing, development, maintenance, repair, and shop or yard work (Groves).

Historically, the mining industry has been one of the most hazardous work environments in almost every country where this work is performed.  Despite many efforts to reduce both injuries and fatalities, the number of these is still considered by many to be unacceptable (Kecojevic, Komlijenovic, Groves and Radomsky).  According to the Mine Health and Safety Administration (MSHA), the number of deaths in mining has declined from 73 in 2006 to 36 in 2012.  In addition, the injury rate has decreased from 3.64 to 2.56 (per 100 workers) in that same time frame.  Despite these reductions in injuries and deaths, much could still be done in the industry to further decrease the risks associated with mining and thus protect workers from unnecessary harm or death.

In a review of mining related injuries from the period of 1995 to 2004 the most cited injury was a result of mining equipment such as non-powered hand tools.  This accounted for the largest number of lost day injuries, even though it has a relatively low severity rate.  The second most prevalent injury occurred form off road and underground ore haulage.  It should be noted that this type of injury had the highest death rate of all injuries.

In the mining industry, such as in other industries, numerous programs can be put into place in order to minimize the risks involved in working in such a hazardous environment.  Employers and decision-makers can adopt a proactive attitude and develop a safety program that will address worker-oriented tasks with respect to the conditions of these environments (Saleh 2010).  In a study by Grayson (2001), there was a positive correlation between the profitability of the mine and the rate of illness and injury.  Financially-strong minds can reduce the incidence of occupational injuries by investing an effective safety program.  For example, they can hire more-experienced workers and also provide comprehensive training programs geared toward safety.  It has been shown in other studies that an increased awareness of worker’s safety can also increase profitability.  This is done by lowering the direct and indirect costs associated with injuries and fatalities (Brody et al., 1990; Cutler and James, 1996; Yakovlev and Sober, 2010; Moore et al., 2010).  The direct cost that are those associated injuries including insurance and wage premiums, worker’s compensation benefit payments, and a disruption in productivity associated with injuries.  There are also indirect costs such as finding replacement workers, increased paperwork, and a decrease in employee morale which can affect production.

If a mine is not very profitable employers might be reluctant to direct funds toward creating an injury prevention program, especially if the injuries in the past have not been that severe or frequent (Hopkins, 1999).  This means that less profitable mines will not divert scarce financial resources from producing a product to create a strong safety program because the short-term benefits might not seem to exceed the costs of injury prevention.

The creation of a strong safety program will involve an extensive commitment from all levels of the company from the worker all the way to the upper management.  It should focus on three elements that need to be linked together.  Those elements are engineering, education, and enforcement.  Planning as well as program and policy implementation must be followed by regular monitoring and control activities.  This will involve a commitment from supervisors and team leaders to ensure that all training requirements are followed at all times and no one deviates from the program.  The safety-management decisions that must be made to select and prioritize the problem safety areas and system weakness must be based on the recognition of hazards encountered in each activity of the mining process and also problem areas that are discovered in other mines throughout the industry (Groves 2007).

This study will examine the injury and illness rates of companies that have a high profitability rate and those that are less profitable.



            Presently, the mining industry is a valuable asset to the world’s economy but at the same point continues to produce a very dangerous environment.  This has severe consequences for the mining workers as well as the profitability of the mine itself.  The risks associated with working in this type of environment can be minimized by establishing a safety program that addresses worker-oriented tasks and ergonomics.  Worker oriented practices attempt to address the individual needs of the mining employees and the tasks they perform.  By providing extensive training on industry accepted practices the company can ensure that their employees are being safe while also being productive.  This training will need to be monitored for compliance by the employee while out in the field.  If the employee feels that the company is proactively interested in their safety than they are more likely to have a higher stake in the success of the company.  This will lead to less sick days, less injuries, and a decrease in turnover rates.

Furthermore, a financial commitment to the safety program will allow companies to hire more experience workers that will act as mentors to the younger employees.  In a study by Groves, Kecojevi, and Komljenovic, it was shown that there is an increased risk of non-fatal injury among newer employees and a large majority of recorded incidents involved workers with < 5 years of experience.  Having experienced workers act as team leaders or task leaders will decrease the injury rates by having them look out for safety issues when preforming certain tasks.  Management should monitor the safety records of each team leader and acknowledge any positive behavior to reinforce their commitment to safety.  On the other hand, unsafe behaviors should be addressed and corrected as needed.  This will further increase the establishment of safety culture within the company.

Methods and Research

            Since the characteristics of the safety practices in different countries cannot assumed to be similar, it will be reasonable to focus on one particular region of the world.  In this study, the investigator will focus on the mining industry in southeastern region of the United States.  The mining industry is suitable for this type of study due to its high risk of injury and historically has been lacking in sufficient safety programs that are well known in the manufacturing and construction fields.

The purpose of this analysis is the empirical investigation of the issues of safety and ergonomics in the mining industry.  In particular, the study addresses the question of whether or not increases in safety practices decrease the injuries associated with the mining industry such as injuries from non-powered hand tools and underground ore haulage.  This analysis will utilize a retrospective case control approach.  The investigator will survey mining employees that have sustained injuries in the last five years and also survey employees that have no recordable injuries in that same time period.  This will be performed by a use of a survey that will address the safety initiatives and ergonomic risk factors of the company in which they work for at the time of their injury of absence thereof.  As potential responders, mining employees were chosen because of their direct contact with the working conditions that this study attempts to investigate.

The questionnaire will address harmful tasks and conditions in the mining environment, potential ergonomic practices, and economic performance indicators.  The questions for this analysis are (as shown in appendix) are measure by a five-point Likert scale.  After the surveys have been collected and tabulated, they will be analyzed and placed into four different categories:

  • Positive safety program – high rate of injury
  • Positive safety program – low rate of injury
  • Negative safety program – high rate of injury
  • Negative safety program – low rate of injury

Injury Status

Exposure Status



Positive Safety Culture



Negative Safety Culture




A + C

B + D



Using this chart and the formula for odd ratio we can measure the association between variables.  The formula is as follows:  OR = AD/BC.  If the odds ratio is more than 1.0 than there is a positive association between the exposure and the rate of injury.  If the odds ratio is less than 1.0 then there is a negative correlation between the variables.





Describe the working conditions              Unacceptable                                   Acceptable

Within you company in regards                        1                                                              5

To safety and ergonomics

                                                                                                1          2          3          4          5         

Manipulation of loads (lift, carry, and/or push                1          2          3          4          5

Forced Postures                                                                   1          2          3          4          5

Tasks in awkward spaces                                                  1          2          3          4          5

Vibration emitting tasks                                                      1          2          3          4          5

High repetition rates                                                                        1          2          3          4          5

Short recovery time                                                              1          2          3          4          5

Temperature (hot or cold)                                                   1          2          3          4          5

Noise                                                                                      1          2          3          4          5

Time pressure                                                                       1          2          3          4          5

Tasks requiring maximum effort                                        1          2          3          4          5

Contact with chemicals                                                      1          2          3          4          5         

Describe company’s commitment to         Unacceptable                                   Acceptable

Safety and Ergonomics                                       1                                                 5

                                                                                                1          2          3          4          5         

Job rotation to avoid repetition                                          1          2          3          4          5

Use of power tools to avoid strain                                     1          2          3          4          5

Use of lifting aids for heavy loads                                                1          2          3          4          5

Correct ergonomic postures                                               1          2          3          4          5

Safety Training in all areas                                                1          2          3          4          5

Sufficient staff to help minimize work                              1          2          3          4          5

Aid in manual materials handling                                                1          2          3          4          5

Proper medical intervention                                               1          2          3          4          5         

Please evaluate to which degree             Unacceptable                                   Acceptable

The following have been economic                  1                                                             5

And social goals have been achieved

By the company

                                                                                                1          2          3          4          5         

Increased productivity                                                         1          2          3          4          5

Fewer mistakes and defects                                              1          2          3          4          5

Less days of absence                                                         1          2          3          4          5

Reduced turnover                                                                1          2          3          4          5

Increased health of workers                                              1          2          3          4          5

Reduction of workloads                                                      1          2          3          4          5

Increased safety/fewer accidents                                     1          2          3          4          5

Increase in worker morale                                                  1          2          3          4          5

Higher worker satisfaction                                                 1          2          3          4          5

Less loss time accidents                                                     1          2          3          4          5






Brody, B., Letourneau, Y., Poirer, A., 1990. An indirect cost theory of work accident

prevention.  Journal of Occupational Accidents 13, 255-270.

Cutler, T. JamesP., 1996. Does safety pay? A critical account of the health and safety

executive document: “The Costs of Accidents”. Employment and Society 10 (4),


Grayson, R.L., 2001. Safety vs productivity and other factors in US underground coal

mines. Mining Engineering 53 (8), 40-44.

Groves , W.A., Kecojevic, V.J., Komljenovic, D., 2007. Analysis of fatalities and injuries

involving mining equipment .  Journal of Safety Research 38(4), 461-470.

Hopkins, A., 1999. For whom does safety pay? The case of major accidents. Safety

Science 32, 143-153.

Kecojevic, V., Komljenovic D., Groves, W., $ Radomsky, M. (in press).  An analysis of

equipment-related fatal accidents in U.S. mining operations; 1995-2005. Safety

            Science. Doi: 10.1016/j.scci.2006.08.024

Mine Safety and Health Administration (MSHA). (2012).  Injury rates. Available from

Moore, S.M., Pollard, J., Mark, C. Bhatt, S.K.., 2010.  An analysis of the potential of roof

screening to reduce workers compensation costs. Mining Engineering

(December), 49-54.

Saleh, J.H., Marais, K.B., Bakolas, E., Cowlagi, R.V., 2010.  Highlights from the

literature on system safety and accident causation:  review of major ideas, recent

contributions, and challenges.  Reliability Engineering and System Safety 95

(11), 1105-1116.

Yakovlev, P., Sobel. S.R., 2010. Occupational safety and profit maximization: friends or

foes? Journal of Socio-economics 39 (3), 429-435.