Using Multiple Complementary Methods to Develop ...

PROCEEDINGS of the HUMAN FACTORS and ERGONOMICS SOCIETY 56th ANNUAL MEETING - 2012

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Using Multiple Complementary Methods to Develop Ergonomics Audits for Mining Operations Patrick G. Dempsey1, William L. Porter1, Jonisha P. Pollard1, and Colin G. Drury2 1

National Institute for Occupational Safety and Health Office of Mine Safety and Health Research Pittsburgh, PA 15367 2

University at Buffalo Buffalo, NY 14260

Although ergonomics audits are commonly used by consultants, the scientific literature on reliable and valid audits is sparse. This paper describes a multi-faceted methodological approach to developing ergonomics audits for three types of mining operations. The approach was derived from a validated audit (Ergonomics Assessment Program (ERNAP)) for aircraft maintenance operations. While there were contextual, regulatory, and intended end user differences, the general approach to establishing content validity through task analysis and workplace observations, surveillance data, and accepted practices and regulations proved to be effective, albeit with modifications. Analysis of fatality reports and desire for integration with existing mining safety approaches were two areas where the current approach differed from ERNAP.

Not subject to U.S. copyright restrictions. DOI 10.1177/1071181312561264

INTRODUCTION Auditing an entity involves performing an examination of it with a specific purpose. Dictionaries emphasize official examinations of financial accounts, reflecting the accounting origin of the term. In ergonomics, the term is broadened to include nonfinancial entities, but remains faithful to the concepts of checking, acceptable policies/practices, and consistency (Drury and Dempsey, 2012). More specifically, an ergonomics audit provides a comprehensive measurement at a specific point in time of how well jobs and workplaces have been designed from an ergonomics standpoint (Koli et al., 1998). In this context, the use of the term ergonomics audit by consultancies to denote an examination of an organization’s ergonomics program is not intended here. Workplace audits in this context provide a measure of how effectively or comprehensively ergonomics has been applied. As such, in mining operations, the audits can be repeated at different points in time as the work environment changes due to ergonomic changes, production or equipment changes, or changes in conditions or locations. In contrast to analysis of incident/injury reports, audits are proactive tools and can be used to help a mining organization to identify which divisions, plants, or departments can most benefit from ergonomics input. Audits can also be used by non-experts, which is a distinct advantage for mining where ergonomists are still uncommon. A properly designed ergonomics audit can even be more thorough than an expert practitioner with respect to identifying ergonomics deficiencies in the workplace (e.g., Koli et al., 1998). In spite of progress to address ergonomics in mining, significant opportunities to improve working conditions remain. Slips and falls and musculoskeletal disorders are significant problems. Over 60% of lost-time injuries at surface

mining locations are attributable to materials handling or slip or fall of person alone (National Institute for Occupational Safety and Health (NIOSH), 2007). The results of this study clearly indicate that there is a need to audit and address slips and falls and musculoskeletal disorder risk factors in the operations studied. The current effort focused on mining sector bagging operations, haul truck operations, and maintenance and repair operations in preparation (coal) and processing (minerals) plants. One reason for choosing haul truck and bagging operations was that previous research by the team had indicated ergonomics issues. The maintenance and repair operations were chosen due to their extent in preparation and processing plants and the associated injuries. The three operations chosen also provide three distinct types of exposures. While bagging operations are cyclic and have more traditional repetitive materials handling tasks (e.g. palletizing) and upper extremity stressors (e.g. closing bags), maintenance and repair is characterized by non-repetitive tasks performed in a variety of work locations. Haul truck operations are characterized by repetitive tasks (e.g. driving while exposed to whole-body vibration), as well as nonrepetitive tasks (e.g. exiting the cab to change filters or clean windows). Testing across these diverse operations also allows for an exploration of the strengths and weaknesses of the ergonomics audit approach for different types of operations. The main focus of this paper is the collection of data and information to provide content validity of the developed audits. The primary challenge is to cast a net wide enough to capture the majority of ergonomics deficiencies that can be expected within the constraints of time and budget. This paper discusses and contrasts several techniques used to develop content and provide recommendations for future audits.

PROCEEDINGS of the HUMAN FACTORS and ERGONOMICS SOCIETY 56th ANNUAL MEETING - 2012

METHODS Methods for each of the studies are described briefly. For the studies involving human subjects, prior approval from NIOSH’s Human Subjects Review Board was obtained and subjects signed informed consent forms. MSHA Data The operations studied were subject to the Mine Safety & Health Administration (MSHA) regulation contained in Title 30 (Minerals Resources), Part 50 of the United States Code of Federal Regulations (CFR) that requires mines to report all occupational injuries and illnesses. Data on fatalities, nonfatal injuries with lost days cases, and nonfatal injuries with no days lost between 2004 and 2008 were initially retrieved. Although these types of data have inherent limitations due to potential issues such as coding accuracy and bias and the somewhat limited information provided, the data are still extremely useful to characterize the most significant sources of injuries. The MSHA data also include narratives which can negate some of the limitations mentioned (Lincoln et al., 2004). For each of the three types of operations, different classifications were used to help identify cases. For bagging operations, source of injury/illness code 04 (bags) was used. For maintenance operations, regular job titles of injured/ill worker of code 04 (mechanic/repairman/helper) or code 104 (mechanic/repairman/helper) were used as was a mine worker activity at time of injury/illness of code 39 (machine maintenance/ repair). For the haul truck analysis, mine worker activity at time of injury/illness of code 55 (operating haulage truck) or regular job title of code 76 (truck driver) were used for the initial selection. The latter were manually classified to determine whether the truck was a haul truck. Fatality Reports Although not originally planned, an analysis of fatal investigation reports produced by MSHA (reports can be downloaded at http://www.msha.gov/fatals/fab.htm) was performed for haul truck and maintenance and repair operations. The analysis was undertaken to understand the types of failures that can lead to fatal accidents, identifying underlying patterns with ergonomics implications that would then drive development of audit items. Such an analysis requires a solid sample of investigations which was available. The detailed analysis of haul truck fatal accident patterns is discussed in detail by Drury et al. (2012). Worksite Observations & Interviews Worksite observations and informal interviews are among the most critical methods used to determine audit content. Several person-months of observations and interviews were carried out over several years. A number of preliminary visits were made at the proposal development stage. Once the project was initiated, extensive worksite observation was conducted, often in conjunction with specific

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data collection efforts that formed the field studies discussed below. Extensive interactions with workers performing the operations of interest, first-line supervisors, and safety and health personnel at mine sites were carried out. This included fact finding on issues such as administrative policies, how work was assigned, and suggestions for problematic tasks or equipment to observe. When possible, policies or procedures that could be shared were requested as were any information on maintenance records or any other information that could be helpful to understanding the operations. Task Analysis Task analysis is one of the most widely used and robust ergonomics tools for systematically analyzing work requirements and opportunities for error. An atypical step in the process here was to derive initial hierarchical task descriptions from fatal accident reports where detailed task data were often recorded (Drury et al., 2012).These initial task descriptions provided a detailed hierarchical description of work and allowed the level of detail to be tailored during observation to the level required for audit development. Most task analysis was completed from watching videos of task performance, particularly for the more complex maintenance tasks. An earlier generic task description of maintenance activities also helped structure the observations (see Drury et al., 2012). This allowed the hierarchical task descriptions to be formulated, often in conjunction with notes taken in the field. Note that task descriptions had been used to structure earlier audit developments, e.g. Koli et al. (1998). Field Studies Field studies were designed to accommodate the specific nature of the work and exposures common in the three different types of operations. For the bagging operations, the focus was on the physiological and biomechanical demands of small bag filling and stacking (see Gallagher et al., 2011 for details). For haul truck operations, an investigation of the impact of operating haul trucks on postural stability and upper extremity performance (grip force and tactile sensitivity) is being conducted in the context of one work shift. Exposure to upper extremity and whole-body vibration is being measured as vibration is the exposure of most concern. Vibration was measured for entire shifts while the human performance measures were taken pre-, mid- and post-shift. For maintenance and repair, the diverse nature of the work and the variable work locations posed significant obstacles. Some initial data collection on joint postures using electro-goniometry and foot pressures using an in-boot pressure transducer was conducted. This was only partially successful as the goniometers were not able to withstand the environmental demands of mining. A video-based ergonomics analysis was also carried out (see Heberger et al., 2012 for details). The overall goal was to be able to make inferences about how specific tasks or task elements during maintenance and repair operations were related to postural exposures, tool

PROCEEDINGS of the HUMAN FACTORS and ERGONOMICS SOCIETY 56th ANNUAL MEETING - 2012

use, slip and fall risk, and other exposures found in the injury records. Laboratory Studies Laboratory studies are being utilized in a limited fashion to investigate specific issues with respect to either formulating audit items or developing solutions to audited items. The studies are currently being conducted and to date include an investigation of bagging palletizing station layout and a study of slip and fall potential on varying types of walkways and grades for coal preparation and mineral processing plants. Code of Federal Regulations In the case of the current study, all operations visited were subject to the MSHA regulations contained in Title 30 (Mineral Resources), Parts 1-199 of the United States Code of Federal Regulations (CFR). The relevant parts of the CFR were examined for each type of operation so that they could be used to derive audit items, support the development of audit items, or provide support for recommendations developed to address audited issues. RESULTS Each of the methods described here was found to be useful, with strengths and weaknesses that were often complementary. Table 1 presents an overview of the findings with respect to methodological considerations. The surveillance data were used in several different ways. Previous analyses were initially consulted. For example, an analysis of injuries due to falls from equipment (Moore et al., 2009) was used to formulate some of the initial research questions or areas for investigation in the haul truck study. The formal analysis of haul truck injuries (Santos et al., 2010) then more acutely examined injury sources. Similar analyses for the other two types of operations were carried out. In addition to these analyses, which directed or helped target specific issues for investigation during field visits, other analyses were performed iteratively to investigate, for example, whether particular types of injuries mentioned during field visits were common (e.g., injuries with specific tools). Overall, the analysis of surveillance data has significant advantages in that the mining injury, illness, and fatality data are available in non-aggregated form (e.g., OSHA 300 log data summaries published by the Bureau of Labor Statistics). Their availability and low cost are significant advantages, although workers’ compensation claims data would be a viable substitute if applicable and if the data could be made available. The analysis of fatal accident investigation reports was not originally planned, but provided significant information on less common types of accidents with the most severe consequences. Patterns of fatal accidents, even if in small numbers, often have implicit or explicit implications for ergonomics. The circumstances that lead to such severe accidents are not always observable and may be related to more latent factors. Going forward, an analysis of fatalities

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during maintenance and repair operations will be carried out using a similar approach to that used by Drury et al. (2012) for haul trucks. Observations and interviews were among the most useful and informative methods utilized. In addition to information derived from surveillance data, these methods allow operators to provide their views on the most demanding tasks, how factors such as weather or production demands impact their workload, as well as providing suggestions for how to reduce exposures noted during the observations. In addition to operators, managers provided invaluable information on policies and procedures for practices such as lockout/tagout, fall protection, training, and related organizational-level issues. In some cases, standard operating procedures or related methods for planning work can be contrasted with how work is actually performed. Note the similarity to the traditional issue in task analysis of whether to record how work should be performed or how it is performed (Drury, 2009). This is also similar to the contrast between planned work and what has been called ‘real work’ in the context of activity analysis rooted in French ergonomics. This phenomenon has been noted for maintenance work (Garrigou et al., 1998). The observations and interviews were carried out contemporaneously with the field studies mentioned. The overall goal of each field study was specific to the type of operation under study and was meant to quantify exposures to the risk factors identified from previous studies in the literature, surveillance data, and observations and interviews conducted during preliminary mine visits. These studies were all resource-intensive and represent the most challenging in that it is difficult to find mine sites willing to collaborate. Although these studies provide fewer short-term benefits, they offer the potential to provide detailed exposure assessments that have value beyond the audit development. Knowledge gained from these efforts has implications for the overall mining ergonomics program since the level of detail and quantification generate additional research questions. The laboratory studies have a similar role, although the issue of collaborators may be negated if the studies are to be carried out with non-mining subjects in the laboratory. These studies do have the disadvantage of testing mock-ups, which cannot be conducted in the actual work environment. One of the less structured methods used was that of obtaining documentation or data from individual mines. There are varying degrees of information on maintenance tasks, standard operating procedures, and similar related information that could be used to help guide development of the audit. In the case of haul trucks, it was helpful to consult original equipment manufacturers’ (OEM) materials such as training and operation manuals. It was not uncommon for mines to describe a policy or procedure and indicate that it was not in written form nor was it strictly enforced. Conversely, there were occasions where information could not be shared due to proprietary or related concerns. There is also a considerable amount of information available on the World Wide Web, although vetting that information can be challenging when it does not come from a recognized and reputable source. The MSHA regulations provide a number of challenges as they are not typically focused on ergonomics issues. However,

PROCEEDINGS of the HUMAN FACTORS and ERGONOMICS SOCIETY 56th ANNUAL MEETING - 2012

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Table 1. Comparison of strengths and weaknesses of sources of audit content. Content Input * Surveillance data

Strengths - Low cost and readily accessible - Easy identification of attributed causes of most frequent and severe injuries

Fatality/accident reports

- Often detailed descriptions of equipment, environment, operators, and task(s) being performed at time of accident - Can be used to identify rare events that may not be captured by any of the other sources - Provide detailed user insight - Experienced operators can often quickly identify key ergonomics issues

* Observation/interview

* Task analysis

- Task descriptions provide detailed structure and content of tasks - Level of detail can be tailored to the requirements of the analysis

* Field studies

- Provide detailed information on ergonomics deficiencies and exposures

* Laboratory studies Maintenance records and production documentation

- Highly specific results that provide detailed audit items or solutions to audited items - Readily available - Allow trends to be quickly identified - Allow determination of frequently performed operations and tasks

Work documentation (training materials/standard operating procedures, etc.)

-Readily available -Required by MSHA -Detailed description of “safe” procedures

Weaknesses - Ergonomics issues typically not identified - Potential for misclassification - Do not capture near misses or events without injuries or fatalities - May not be conducted by ergonomists which may limit reporting of and inference about ergonomics issues that contributed to accident - Operators may feel compelled to perform tasks in certain ways when observed - Some operators reluctant to be observed or interviewed - Time consuming - Can be difficult to observe all tasks - Maintenance tasks (other than preventive) in particular may be difficult to observe due to ad hoc timing - Higher costs and time - May be biased due to potential observer bias - Must be tailored to the nature of the individual type of operation being studied - Higher costs and time - Narrow applicability of results (typically) - Content will vary considerably from company to company - Nomenclature often company-specific - Production documents have implications for ergonomics risk factors but do not provide documentation of them - Do not capture related injuries -Best case scenario -Planned work may differ from how employees actually do work -May not be up to date

* Indicates items originally planned to be included they do clearly support a number of safety issues noted such as seat belt use and fall protection. The audit will likely provide some complementary guidance such as designing machining guards to be more ergonomic (e.g. modular with handles) while also satisfying the guarding requirements. DISCUSSION Ergonomics audits have not been widely used and yet represent an opportunity to provide reliable and valid methods for organizations to assess how well their operations have been designed from an ergonomics standpoint. The initial approach used for developing mining audits was derived from an earlier aircraft maintenance audit with modifications, as well as compilations of existing ergonomic audits (Drury and Dempsey, 2012). The core approach of using workplace observation and task analysis as the basis proved to be

appropriate, with the addition of some of the other approaches discussed to better suit the mining operations studied. Mining operations and aircraft maintenance have rather divergent formalities in specification of work, yet the overall approach was robust to these differences. The bagging audit draft focuses on musculoskeletal disorder risk factors in that the jobs typically involve physical tasks such as opening and attaching bags to filling devices (both bulk and small bags), palletizing, and weighing. The haul truck audit draft is quite different from that for haul truck operation since there are issues with ingress/egress and the potential for fall from heights, compliance with seat belt use, and issues with collisions or incursions with vehicles or buildings. Thus, the nature of the ergonomics issues is diverse. The maintenance and repair audit draft is similarly complex because compliance issues such as lockout/tagout procedures exist and because there are organizational issues associated

PROCEEDINGS of the HUMAN FACTORS and ERGONOMICS SOCIETY 56th ANNUAL MEETING - 2012

with how work is assigned and planned. The maintenance and repair audit will address these in addition to slip and fall issues, materials handling, tool use, walkway and stairway design, and other identified issues. For all three audits, some of the content from Koli et al. (1998) will be used such as the assessment of lighting and thermal environment. The next phase of research—to evaluate the reliability and validity of the audits—will provide an objective test of the approach in the mining context.

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Heberger, J.R., Nasarwanji, M.F., Paquet, V.L., Dempsey, P.G., and Pollard, J.J. (2012). Video Based Ergonomic Job Analysis in Mining Mills and Preparation Plants. In: Proceedings of the Human Factors and Ergonomics Society 56th Annual Meeting, submitted. Santa Monica, CA: Human Factors and Ergonomics Society (in press). Koli, S., Chervak, S., and Drury, C.G. (1998). Human Factors Audit Programs for Nonrepetitive Tasks. Human Factors and Ergonomics in Manufacturing, 8(3), 215-231.

REFERENCES Drury, C. G., (2009). Task Analysis and Cognitive Work Analysis : Requirements for Worker Competencies and Beyond. In A.M. Bisantz and C.M. Burns (eds), Applications of Cognitive Work Analysis. Boca Raton: CRC Press, pp. 229-248. Drury, C.G., and Dempsey, P.G. (2012). Human Factors and Ergonomics Audits. In G. Salvendy (ed.) Handbook of Human Factors and Ergonomics, 4th edition, New York: John Wiley & Sons, pp. 1092-1121. Drury, C.G., Porter, W.L. and Dempsey, P.G. (2012). Patterns in Mining Haul Truck Accidents. In: Proceedings of the Human Factors and Ergonomics Society 56th Annual Meeting, submitted. Santa Monica, CA: Human Factors and Ergonomics Society (in press). Gallagher, S., Pollard, J., Manke, N. and Heberger, J. (2010). Field assessment of biomechanical and physiological demands in sand and limestone bagging operations. In: Proceedings of the Human Factors and Ergonomics Society 55th Annual Meeting, Santa Monica, CA: Human Factors and Ergonomics Society, pp. 1002-1006. Garrigou, A., Carballeda, G., and Daniellou, F. (1998). The role of ‘know-how’ in maintenance activities and reliability in a high-risk process control plant. Applied Ergonomics, 29(2), pp. 127-131.

Lincoln, A.E., Sorock, G.S., Courtney, T.K., Wellman, H.M., Smith, G.S., and Amoroso, P.J. (2004). Using narrative text and coded data to develop hazard scenarios for occupational injury interventions Injury Prevention, 10, 249-254 Meghashyam, G. (1995). Electronic Ergonomic Audit System for Maintenance and Inspection. In: Proceedings of the Human Factors and Ergonomics Society 39th Annual Meeting, Santa Monica, CA: Human Factors and Ergonomics Society, pp. 7578. Moore, S.M., Porter, W.L., and Dempsey, P.G. (2009). Fall from equipment injuries in U.S. mining: Identification of specific research areas for future investigation. Journal of Safety Research, 40(6), 455-460. NIOSH (2007). http://www.cdc.gov/niosh/mining/statistics/, accessed 3/16/2012. Santos, B.R., and Porter, W.L., and Mayton, A.G. (2010). An Analysis of Injuries to Haul Truck Operators in the U.S. Mining Industry. In: Proceedings of the Human Factors and Ergonomics Society 54th Annual Meeting, Santa Monica, CA: Human Factors and Ergonomics Society, pp. 1870-1874. DISCLAIMER The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health.