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1 1 Author: Krumenauer, Luke, W Title: An Ergonomic Analysis of the Widget Production Line at Company XYZ The accompanying research report is submitted to the University of Wisconsin-Stout, Graduate School in partial completion of the requirements for the Graduate Degree/ Major: M.S. Risk Control Research Adviser: Elbert Sorrell Submission Term/Year: Summer, 2012 Number of Pages: 73 Style Manual Used: American Psychological Association, 6th edition I understand that this research report must be officially approved by the Graduate School and that an electronic copy of the approved version will be made available through the University Library website I attest that the research report is my original work (that any copyrightable materials have been used with the permission of the original authors), and as such, it is automatically protected by the laws, rules, and regulations of the U.S. Copyright Office. My research adviser has approved the content and quality of this paper. STUDENT S NAME: Luke W. Krumenauer STUDENT S SIGNATURE: DATE: 08/18/2012 ADVISER S NAME: Elbert Sorrell ADVISER S SIGNATURE: DATE: 8/18/ This section for MS Plan A Thesis or EdS Thesis/Field Project papers only Committee members (other than your adviser who is listed in the section above) 1. CMTE MEMBER S NAME: SIGNATURE: DATE: 2. CMTE MEMBER S NAME: SIGNATURE: DATE: 3. CMTE MEMBER S NAME: SIGNATURE: DATE: This section to be completed by the Graduate School This final research report has been approved by the Graduate School. (Director, Office of Graduate Studies) (Date)

2 2 Krumenauer, Luke W. An Ergonomic Analysis of the Widget Production Line at Company XYZ Abstract The purpose of this study was to perform an ergonomic-based analysis of the widget production line to determine the extent of the potential ergonomic issues at company XYZ. This was due to the problem of company XYZ s presence of ergonomic-based risk factors on the widget production line that could potentially affect employee health and well-being. This study reviewed literature which included ergonomic-based information. This was necessary to understand research options to potentially eliminate or reduce the problem. The research conducted in this study included a revised National Institute of Occupational Safety and Health (NIOSH) lifting equation, a Rapid Entire Body Assessment (REBA), and an employee risk perception survey. The research results provided insight to the employee ergonomic-based risk exposure, as well as the employee risk perceptions. Study recommendations for company XYZ, conclusions, and a summary provide a detailed final chapter.

3 3 Table of Contents... Page Abstract...2 List of Tables...6 Chapter I: Introduction...7 Statement of the Problem...10 Purpose of the Study...10 Questions of the Study...10 Justification of the Study...11 Limitations of the Study...11 Assumptions of the Study...12 Definition of Terms...12 Chapter II: Literature Review...13 Work...13 Ergonomics...15 Ergonomic-based Risk Factors...16 Ergonomic-based Employee Injuries and Illnesses...19 Ergonomic-based Injury and Illness Costs...20 Human Skeletal System...22 Individual Employee Risk Factors...25 Whom to Design a Workstation For...26 Workstation Design...28

4 4 Ergonomic Evaluation...29 Employee risk perception survey...31 Revised NIOSH lifting equation...32 REBA...36 Ergonomic Instrumentation...38 Ergonomic Controls...39 Cost Analysis of Back Injuries...41 Chapter III: Methodology...43 Research Methods...43 Sample Selection...44 Instrumentation of Research...45 Procedures Utilized to Conduct Research...46 REBA...46 NIOSH...46 Risk perception survey...47 Cost effectiveness comparison...47 Research Data Analysis...48 Chapter IV: Results of Study...50 Question #1: Perform an ergonomic analysis of the widget production line to determine/identify ergonomic risk factors that impact employee health an well-being...50 Question #2: Determine the risk perception of employees performing the job...53 Question #3: Determine the cost effectiveness of a control that prevents overexertion injuries pertaining to the lower back...55

5 5 Chapter V: Summary, Conclusions and Recommendations...57 Summary...57 Restatement of the problem...57 Methods and procedures...57 Major findings...57 Conclusions...58 Recommendations...59 Recommendations related to this study...59 Recommendation # Recommendation # Recommendation # Recommendation # Recommendation # Recommendation # Recommendations for further study...61 References...62 Appendix A: Revised NIOSH lifting equation asymmetry graphic...65 Appendix B: REBA worksheet...66 Appendix C: Risk perception survey...67 Appendix D: Revised NIOSH lifting equation evaluation...69 Appendix E: REBA evaluation...70 Appendix F: Cost effectiveness comparison evaluation...71

6 6 List of Tables... Page Table 1: Frequency Multiplier Table...72 Table 2: Coupling Multiplier Table...73 Table 3: Risk Perception Survey Results...55

7 7 Chapter I: Introduction Work is the physical input of effort exerted by employees in order to perform desired tasks and functions of the job (Chengalur, 2004). In an ideal situation, employees would not be injured as a result of the work that they perform. However, when employees perform work a number of factors could negatively impact the human body. The study of these factors and their affects on the body is known as ergonomics (Tayyari & Smith, 1997). Individual factors that affect the human body during work include; the time or duration of the task, frequency of the task performed, forces exerted on the body, postures of the body during the work, and the environmental conditions in which the work takes place. These factors are known as ergonomic risk factors (MacLeod, 1995). MacLeod (1995, p. 105) states The more factors involved and the greater the exposure to each, the higher is the chance of developing a disorder. When exposures to risk factors contribute to overexertion, employees may develop a multitude of injuries and illnesses. The injuries and illnesses include, but are not limited to; musculoskeletal disorders (MSDs), cumulative trauma disorders (CTDs), dermatologic disorders, and many others (Tayyari & Smith, 1997, p.154). The employee risk factors addressed above, and many like them, can be controlled (MacLeod, 1995). In order for ergonomic risk factors to be controlled or reduced, employees must fit the job or the job must fit the employee (Tayyari & Smith, 1997; Chengalur et al., 2004)). In order for the employee to be comfortable with the job, the job s clearance and reach dimensions must be acceptable of the employee s clearance and reach dimensions (Tayyari & Smith, 1997). Job tasks and workstations designed for a wide working population may reduce the opportunity for employee injury and illness (Chengalur, 2004). Workstations that fit any employee are designed by determining and implementing acceptable anthropometric job tasks and activities.

8 8 Anthropometric data is information that determines the population s physical size dimensions (Chengalur, 2004). The Liberty Mutual Manual Material Handling Guidelines list the capabilities and limitations of the population when lifting, lowering, pushing, pulling, and carrying (Chengalur, 2004). Anthropometric data and the Liberty Mutual Manual Material Handling Guidelines can be utilized to design job tasks that account for a large portion of the population. This may allow a wide range of employees to perform job tasks with comfort. When employers develop workstations that fit employees, employee health and wellbeing may be protected by reducing or eliminating the ergonomic risks to employees within the workstation (Chengalur, 2004). The benefits of a well designed workstation include improved safety, health, and production. Additionally, when the workstation fits the employee; costs may be reduced, employee well-being could increase, and the workstation s equipment will possibly be easier to operate (MacLeod, 1995). An often overlooked benefit to properly designed workstations that fit employees, is the reduction of workers compensation costs. These well designed workstations may result in fewer amounts of injuries and illnesses. In return, beneficial ergonomic design reduces workers compensation claims, the costs of operation, and benefits the employees (MacLeod, 1995). In 2010 the Bureau of Labor Statistics (BLS) and the Liberty Mutual Workplace Safety Index released information on the private industry sector s employee injuries and illnesses. The BLS total recordable number of private industry sector nonfatal injuries and illnesses was 3,063,400 (BLS, 2012a). MSDs accounted for 9.28 percent of the total injuries and illnesses reported in 2010 (BLS, 2011a). According to the 2010 Liberty Mutual Workplace Safety Index, $53.42 billion dollars was spent on employee injuries and illness, or workers compensation, in 2008 (LMWSI, 2010). Of the $53.42 billion dollars, $13.40 billion was spent on overexertion

9 9 injuries and illnesses. Overexertion injuries and illnesses can occur in one action, or slowly over time (Chengalur, 2004). The $13.40 billion in costs specific to overexertion injuries and illnesses could have possibly been reduced by designing job tasks that are within the capabilities and limitations of the workers (Chengalur, 2004). In smaller private industry sectors, such as the aircraft engine and engine parts manufacturing industry, injuries and illnesses occur as evident by published accident and incidence rates from the Bureau of Labor Statistics (BLS, 2006). In 2006 the BLS released the yearly total recordable number of nonfatal injuries and illnesses in the aircraft engine and engine parts manufacturing industry. This number was 740 nonfatal injuries and illnesses (BLS, 2006). Additionally in 2006, the BLS (2006) released the incidence rates of total recordable number of nonfatal injuries and illnesses in the private industry sector as well as the aircraft engine and engine parts manufacturing industry. The total private industry sector acquired an incidence rate of 4.4 while the aircraft engine and engine parts industry sector s rate was 3.7 (BLS, 2006). This shows that the aircraft engine and engine parts industry s safety performance, as far as recordable injuries and illnesses accounts, is lower than the national average (BLS, 2006). These numbers quantify that opportunities exist for improving the work conditions for employees. In some circumstances, the aircraft engine and engine parts manufacturing industry utilizes employees in workstations to manufacture products that are often large, dense, and made of heavy metals. Employees are involved in many different workstation tasks in order to produce aircraft engines and engine parts. Some tasks require manual material handling, which is when an employee physically exerts energy to move equipment or a product (Tayyari & Smith, 1997). These manual material handling tasks include operating hand tools, installation and removal of products, and physically entering and exiting the workstation with equipment.

10 10 Employees are potentially exposed to risk factors of excessive forces, inadequate employee postures, repetitive motions, duration of task exertion, and environmental conditions. These potential workstation risk factors may have contributed to the 740 recordable injuries and illnesses reported in Company XYZ operates within the aircraft engine and engine parts manufacturing industry. As a necessary function of the workstation tasks, company XYZ utilizes manual material handling on their widget production line. The workstation requires an employee, within a computer numerically controlled (CNC) machine, to manually lower and set a test gauge onto a production part, and then remove the test gauge to verify production part tolerances. If the product meets the tolerance specifications determined by the test gauge, the product is passed to the next stage of manufacturing. If the product does not meet the tolerance specifications, additional machining and tolerance verification are required. This is a common everyday job task that occurs multiple times per day. The potential inadequate employee exposures of this workstation may affect employee health and well-being. Statement of the Problem Company XYZ s presence of ergonomic-based risk factors on the widget production line could potentially affect employee health and well-being. Purpose of the Study The purpose of this study was to perform an ergonomic-based analysis of the widget production line to determine the extent of the potential ergonomic issues at company XYZ. Questions of the Study 1. Perform an ergonomic analysis of the widget production line to determine/identify ergonomic risk factors that impact employee health and well-being.

11 11 2. Determine the risk perception of employees performing the job. 3. Determine the cost effectiveness of a control that prevents overexertion injuries pertaining to the lower back. Justification of the Study This study is necessary to identify the job task risks on the widget production line for company XYZ that may downgrade employee health and well-being. It is necessary to identify the risk factors, in order to understand the impact to the employees working on the widget production line. The risk factors identified will then be addressed utilizing engineering or administrative controls to potentially decrease the likelihood of employee injury or illness. The study will improve the employee work practices and work instructions for company XYZ. The study may improve the present state of knowledge related to aircraft engine and engine parts manufacturing employee ergonomics. This in turn may lower workers compensation rates, and provide a safe and healthy working environment for employees. The study will serve as a basis within the aerospace manufacturing industry and serve as a foundation to assess the associated ergonomic risk factors that downgrade employee health and well-being. This study may impact all manufacturing machining operations and future machine and test gauge designs in the industry. Limitations of the Study 1. The study will be limited to company XYZ. 2. The workgroup population is limited and specialized. 3. The work environment s temperature and humidity are controlled and cannot be changed. 4. Ergonomic instrumentation is limited and only available tools will be utilized. 5. Genetic and medical histories will not be accessed through the workgroup population.

12 12 6. The test gauge, CNC, and product designs will all be limited to their original tolerances. Assumptions of the Study 1. The job task is a routine everyday task. 2. The job task will be performed utilizing two hands, while standing, lifting and lowering the test gauge at a reasonable rate, for no more than an eight hour work day. 3. The employee is physically capable to perform the work, and willing to participate in this study, as well as treat the study as a regular task. Definition of Terms Clearance Dimension. These is defined as the minimum space required for an employee to perform a job task, this dimension is established by the largest individual in a given population. CNC. Computer numerical controlled (Merriam-Webster, 2011a) Ergonomics. The study of work an employee is performing (Tayyari & Smith, 1997). Machining. Machining is a series of activities that utilize chip removal to achieve the desired shape for a quality product (Merriam-Webster, 2011b). Reach Dimension. This is the dimension of the maximum space allowable for an employee to perform a job task, and this dimension is determined by the smallest individual in a given population (Tayyari & Smith, 1997). Test Gauge. An instrument of measurement used for testing (Merriam-Webster, 2011c) Trunk. The human body s torso (Chengalur, Rodgers & Bernard, 2004)

13 13 Chapter 2: Literature Review The purpose of this study was to perform an ergonomic-based analysis of the widget production line to determine the extent of the potential ergonomic issues at company XYZ, and determine if ergonomic-based risk factors on the widget production line could potentially affect employee health and well-being. This chapter reviews prior research on ergonomics, work, ergonomic risk factors, ergonomic-based employee injuries and illnesses, ergonomic-based injury and illness costs, and ergonomic evaluation techniques. Additionally, prior research on the human skeletal system, individual employee risk factors, workstation design, ergonomic instrumentation, ergonomic controls, and a cost analysis of back injuries will provide information to clarify the problem. Work Work is the physical input of effort exerted by employees in order to perform desired tasks and functions of the job (Chengalur, Rodgers & Bernard, 2004). The scope of work ranges vastly, from office to construction workers and from sitting to standing. Employees that exert work are necessary for the world s business s to produce the products and services that are in demand by consumers (Tillman & Tillman, 1991). Historically, the way that we perform work has changed greatly. Forms of new technology have been created to meet consumer demands, and new technology creates changes for many industries (MacLeod, 1995). Changes ultimately alter the work tasks that employees are accustomed to performing. Automation for example, eliminates some work, but various types of manual work for employees may remain (MacLeod, 1995). Although the manufacturing industry utilizes automation whenever possible, manual material handling is still being conducted. Manual material handling (MMH) means that force is exerted by the human, and not the automated computer, tool or mechanical process (Chengalur et

14 14 al., 2004). Whenever humans are involved in a work process, ergonomics becomes an area of concern. In many manufacturing circumstances, employees work within workstations that are designed for product production with MMH tasks (MacLeod, Jacobs, & Larson, 1990). Increasing the efficiency of product movement through a workstation directly improves productivity of manufacturing processes, creating an illusion of increased profits (MacLeod, 1995). Processes that are only created for production proficiency, often lack analysis of how humans will fit within the workstation (MacLeod et al., 1990). Hidden within the increase in productivity, is the increase in work performed by employees (MacLeod et al., 1990). Despite the increased productivity, designing workstations based solely on increasing product movement efficiency may decrease the ability for employees to perform the required job tasks (Tillman & Tillman, 1991). This may lead to health effects in employees, given the increase of manually handled work. Manual Material Handling (MMH) is when employees are used as the source to provide movement of products, materials, or objects from one point to another (Chengalur et al., 2004). MMH occurs in the form of an employee exerting forces during lifting, lowering, pushing, pulling or carrying objects during a job task (Tayyari & Smith, 1997). Employees perform various types of MMH through tasks done by hand or with the help of equipment (Chengalur et al., 2004). An example of tasks done by hand are lifting boxes and pushing them onto a cart (Chengalur et al., 2004). An example of MMH with the help of equipment is pulling and pushing a cart loaded with boxes to a specific location. In each circumstance of MMH work, the employee exerts energy to achieve a desired function of the job.

15 15 Work that incorporates MMH tasks can create injury causing conditions for employees (Tayyari & Smith, 1997). These conditions that cause health issues to employees can be controlled. Controlling injuries in MMH can be performed through many ways (Chengalur et al., 2004). An example of controlling MMH harm to employees is through employee lifting training. In this type of training, employees are presented with proper ways to plan the lift, beneficial hand grip practices, and using the legs to lift heavy objects (Chengalur et al., 2004). This training allows employees to gain knowledge on how to prevent injuries, but the job task may still be dangerous to the health and well-being of the employee. Due to the limits in human physical capabilities, employees are unable to adapt to all work that they perform (MacLeod, 1995). Due to these facts, when employees perform work, a number of factors negatively impact the human body. The study of these factors and their affects on the body is known as ergonomics (Tayyari & Smith, 1997). Ergonomics Ergonomics has been defined by its roots in two Greek words (Tayyari & Smith, 1997). The first word ergon, meaning work, helps define the word. The second word nomiko, meaning law, establishes that ergonomics is the study of work laws (Tayyari & Smith, 1997). Ergonomics defines the field of study of tools and tasks to match the capabilities and limitations of the human user (MacLeod, 1995). MacLeod, Jacobs, and Larson (1990) describe ergonomics as a way of thinking about the design of tools and equipment, the layout of workplaces and the overall organization of work (MacLeod et al., 1990 p. 1). Ergonomics studies the interaction between the human and the work environment (Tayyari & Smith, 1997). The goal of ergonomics is to fit the worker to the work (MacLeod et al., 1990; MacLeod, 1995; Tayyari & Smith, 1997). To properly fit the worker to the work, many disciplines must be

16 16 utilized to draw information from (Tayyari & Smith, 1997). These disciplines include mathematics, biological sciences, psychology, physics, chemistry, engineering technology, and epidemiology (Tayyari & Smith, 1997; Friend & Kohn, 2007). These disciplines are utilized to understand the requirements the environment places on the employee, as well as the capabilities and limitations of the employee (MacLeod, 1995). This data is then analyzed to achieve a favorable relationship between the work environment and the worker, while establishing a balance between productivity and the employee physical health and well-being (Tayyari & Smith, 1997). Establishing valuable data that can identify the dangers to employee health and well-being begins by identifying potential risk factors of the work environment. Ergonomic-based Risk Factors As mentioned in the introduction risk factors in the work environment that affect the human body during work include; the time or duration of the task, frequency of the task performed, forces exerted on the body, postures of the body during the work, and the environmental conditions in which the work takes place (MacLeod et al., 1990; MacLeod, 1995; Tayyari & Smith, 1997). The force risk factor accounts for the forces exerted by the employee to perform the required motions of the job. This risk factor determines the employee s exposure to force exertion. Force may be measured utilizing a force gauge that quantifies the effort exerted, or by utilizing a scale to weigh an object within a manual material handling task (MacLeod, 1995). The time or duration risk factor describes the length of time the employee is exposed to performing the task (MacLeod, 1995; Tayyari & Smith, 1997; Chengalur et al., 2004). The frequency risk factor depicts the number of motions of a specific body part performed by the employee per day. Frequency determines the employee exposure to repetitive motions. The environmental risk factor accounts for the human exposure to temperature, chemical, or

17 17 biological hazards (MacLeod, 1995; Tayyari & Smith, 1997). The posture risk factor examines the position of the body that deviates from the neutral position, and it determines the employee exposure to inappropriate body posture. The neutral position of any body part is the position of least stress or highest strength for each joint (Tayyari & Smith, 1997; Chengalur et al., 2004, p. 667). Several additional risk factors that influence the potential onset of employee injuries and illnesses exist (Tayyari & Smith, 1997; Chengalur et al., 2004). The additional risk factors present within a job task that may affect employee health and well-being include mechanical pressure, vibration, cold exposure, and gloves. Cold exposure is experienced when working in cold environments without proper personal protective equipment (Tayyari & Smith, 1997; Chengalur et al., 2004). Employee exposure to a cold environment could potentially create frostbite, hypothermia, or other types of injuries. Therefore, cold stress creates mental and physical impairments (Chengalur et al., 2004). Within the workplace, employees may be exposed to vibration through the use of tools, machines, or vehicles (Chengalur et al., 2004). Vibration exposure is transferred from the tool, machine, or vehicle to the user. Whole body or hand and arm vibration are the two distinctive types of vibration (Dul & Weerdmeester, 1993; Chengalur et al., 2004). Whole body vibration is transmitted throughout the body, such as when riding equipment within a seated position. Hand and arm vibration is transmitted to the hand and arms through the use of a tool or machine (Dul & Weerdmeester, 1993; Chengalur et al., 2004). Therefore, vibration may increase the difficulty of tasks, generate tingling sensations in the hands, or other MSD s (Chengalur et al., 2004, p. 618).

18 18 Mechanical pressure produced by mechanical objects or tools during a task may place pressure on tissue or nerves increasing the potential for employee injuries and illnesses (MacLeod et al., 1990; Chengalur et al., 2004). When a body part is placed on an object feature like a sharp edge, undesirable handle, or hard edge, pressure within the body part is created. This pressure potentially slows blood flow through the body part increasing the opportunity for swelling and the development of symptoms such as numbness, tingling, and some pain (MacLeod et al., 1990; Chengalur et al., 2004, p. 347). Gloves provide users with hand protection, comfort, and cleanliness (MacLeod et al., 1990; Karwowski & Marras, 1999). However, when gloves are used for job tasks they potentially reduce grip strength as well as decrease the sensory capabilities of touch. Gloves therefore increase exertion needed to perform the same amount of work (MacLeod et al., 1990, p. 12; Karwowski & Marras, 1999). Multiple or single risk factors may be present within an employee task, and understanding how each effects an employee is important to eliminating risk to an employee (MacLeod, 1995). Risk factors have the potential to lead to employee injury and illness (MacLeod, 1995; Tayyari & Smith, 1997). The definite levels of risk factor exposure that may cause injury and illness in a specific individual are undeterminable (MacLeod, 1995). Consequently, the greater the exposure to a risk factor the more substantial the opportunity for employee injury or illness. Each employee is different, and what causes an injury or illness in one employee may not cause an injury or illness in another (MacLeod, 1995; Tayyari & Smith, 1997). The greater the number of risk factors involved in performing a job task increases the likelihood of developing an injury or illness (MacLeod, 1995). Therefore, reducing or eliminating one risk factor in a job task may reduce the potential of injury or illness to an employee. Evaluating the employee ergonomic-

19 19 based risk factors contributes to understanding the level of risk the employee is exposed to (MacLeod, 1995; Charlton & O'brien, 2002; Chengalur et al., 2004). As a result, establishing a level of risk also identifies areas that may contribute to employee injury and illness. Ergonomic-based Employee Injuries and Illnesses The more significant the employee exposure to risk factors while performing job tasks, the greater the potential employees will suffer injuries and illnesses in the forms of musculoskeletal disorders (MacLeod, 1995). Chengalur, Rodgers, and Bernard (2004) state that Musculoskeletal Disorder s (MSD) are disorders of the muscles, tendons, ligaments, joints, cartilage, nerves, blood vessels or spinal discs. Some examples of MSDs are muscle strains, ligament sprains, joint and tendon inflammation, pinches nerves, and spinal disc degeneration (Chengalur et al., 2004, p. 667). Cumulative Trauma Disorder s (CTD) fall under the classification of MSD s. CTD s are a special category of MSD s regarded as repetitive, or cumulative, trauma causing employee injuries and illnesses (MacLeod et al., 1990). This is due to the fact that CTD s have the tendency to occur over a long period of time. The types of injuries and illnesses of MSD s and CTD s are most often caused by overexertion of employees while performing job tasks (Chengalur et al., 2004). Overexertion is when excessive force or effort is required when performing a job task that fatigues an employee s muscles and decreases the employee s ability to continue the task (Chengalur et al., 2004). An employee injury may occur when an employee is forced to perform job tasks beyond the strength capabilities of that individual, or after performing repetitive tasks for an extended period of time. Types of musculoskeletal disorders can occur in all parts of the body (MacLeod, 1995). Ergonomic injuries and illnesses include but are not limited to the following: Herniated disc

20 20 Carpal Tunnel Syndrome Shin Splints Rotator Cuff Tendinitis Strain Sprain Tendinitis Tenosynovitis Osteoporosis Herniated Disc Disc Degeneration Arthritis (MacLeod et al., 1990: MacLeod, 1995; Tayyari & Smith, 1997) These injuries and illnesses are evidence that employee exposure to ergonomic-based risk factors while performing job tasks may cause downgrading of employee health and well-being (MacLeod, 1995). These employee injuries and illnesses will also create many different forms of cost for an organization (MacLeod et al., 1990). Ergonomic-based Injury and Illness Costs An organization s costs stemming from ergonomic related injuries and illnesses are not all directly measureable (MacLeod, 1995). Many indirect costs correlate with ergonomic related injuries and illnesses (MacLeod et al., 1990). Direct measureable costs from ergonomic injuries and illnesses include workers compensation claims and Occupational Safety and Health Administration (OSHA) fines. As employee injuries and illnesses increase, the cost of medical treatment and disability costs also increase (MacLeod et al., 1990; MacLeod, 1995). OSHA can issue fines related to recordkeeping of MSD s and CTD s if the proper paperwork is not updated

21 21 and correct at the time of the organization s OSHA inspection. An organization s indirect costs of ergonomic related injuries and illnesses may include employee turnover, employee absenteeism, decreased employee morale, product defects, and increased administrative costs to list a few (MacLeod, 1995). Additionally, indirect costs are estimated to be four times as expensive in terms of injuries and illnesses to an organization than direct injury and illness costs (MacLeod et al., 1990). Employee s working in uncomfortable work environments that cause fatigue may choose to leave the source of employment, possibly creating a high percentage of employee turnover, absenteeism, or decreasing employee morale (MacLeod et al., 1990; MacLeod, 1995). Employee absenteeism and turnover increase an organization s cost of doing business (MacLeod et al., 1990). Downgrading employee morale affects the employee s ambition for performing quality work. Ergonomic related injuries and illnesses can decrease the quality of products an organization is producing (MacLeod, 1995). Employees that perform job tasks at workstations that are uncomfortable may not be in a position to perform the quality of work required of the organization. Administrative costs may indirectly increase as a result of ergonomic related injuries and illnesses (MacLeod, 1995). This may be due to the increases in required paperwork, by law or the organization, to document all the necessary steps of such an injury or illness (MacLeod, 1995). These direct and indirect costs could possibly be reduced or eliminated by decreasing or removing ergonomic risk factors. Reducing or eliminating ergonomic risk factors can benefit an organization, but they can negatively impact the organization as well as (MacLeod, 1995). Removing or decreasing ergonomic risk factors may lead to the elimination or reduction of musculoskeletal disorders, reduced workers compensation costs, and increased employee health and well-being. It is

22 22 possible that by eliminating ergonomic risk factors within a job that production output may be sacrificed (MacLeod, 1995). Therefore, an organization s earning power may be limited by establishing workstations or job tasks that allow employees to work within their capabilities, slowing production time of products. This emphasizes the importance of the balance between productivity and employee physical health and well-being (Tayyari & Smith, 1997). Productivity has limits and employees are limited in what they can do (Brauer, 1990; page 484 p. 2). Human Skeletal System The skeletal system provides employees with the ability of body movement through the use of many components but most importantly bones, tendons, muscles, cartilage, and joints (Tayyari & Smith, 1997). Bones provide the support of the body as well as the ability of movement with the cartilage and joints. The backbone is the central axis of the skeleton supporting body functions (VanPutte, Regan, & Russo, 2010, p. 127). The backbone consists of five regions which are the cervical, thoracic, and lumbar, sacrum, and coccyx vertebrae regions (Tayyari & Smith, 1997; VanPutte et al., 2010). Additionally, these vertebrae regions are made up of discs. Discs provide cushioning between the vertebrae enabling us to bend and twist (MacLeod et al., 1990, p. 16). The backbone, known as the spinal column as well, provides protection of the spinal nerves (VanPutte et al., 2010). A significant percentage of spinal nerves exit the spinal column between the various vertebrae regions. Furthermore, nerves are responsible for conducting action potentials to and from the central nervous system (VanPutte et al., 2010, p. G-15). The lumbar region is susceptible to injury because this region supports the lower back and the corresponding forces of performing specific tasks. Following or throughout

23 23 prolonged exposure to improper ergonomic risk factors the lumbar region is susceptible to injuries and illnesses (Tayyari & Smith, 1997). A gel like tissue that provides a cushion between the ends of bones and joints is known as cartilage (Tayyari & Smith, 1997; VanPutte et al., 2010; NIH, 2012). Therefore, cartilage is susceptible to injuries and illnesses. Cartilage also heals slowly after an injury because blood vessels do not penetrate it. Thus, the cells and nutrients necessary for tissue repair do not easily reach the damaged area of the cartilage (Tayyari & Smith, 1997; VanPutte et al., 2010, p. 83). A joint is a structure at a specific location where two bones meet (Tayyari & Smith, 1997). In specific cases, joints are the pivoting source between bones (Tayyari & Smith, 1997; VanPutte et al., VanPutte et al., 2010). Two types of joints exist; one allows movement of bones and the other does not (Tayyari & Smith, 1997; VanPutte et al., 2010). These two types of joints are known as diarthrotic joints and synarthrotic joints (Tayyari & Smith, 1997). Diarthrotic joints allow movement, and synarthrotic joints do not. Tendons are a form of body tissue that connects muscle to bone (MacLeod, 1995; VanPutte et al., 2010). Muscles are tissues with the ability to expand and contract, providing a source of power to create movement (VanPutte et al., 2010). These primary components of the skeletal system allow body parts to move with limitations. These components also allow body parts to perform different functions (Tayyari & Smith, 1997; VanPutte et al., VanPutte et al., The types of functions that body parts can execute include flexion, extension, abduction, adduction, supination, pronation, and rotation (Tayyari & Smith, 1997; Chengalur et al., 2004). Flexion is when the angle between two bones decreases with movement, and extension is when the angle between two bones increases with movement. According to Tayyari & Smith (1997) the term abduction means moving away

24 24 laterally from the central axis of the body, and adduction means moving toward the central axis of the body (Tayyari & Smith, 1997, p. 17). Chengalur, Rodgers, and Bernard express supination as rotation of a joint backward and away from the midline of the body; for the hand and arm, palm up and thumb away from the body (Chengalur et al., 2004, p. 676). The opposite is true of pronation, where rotation of a joint forward and toward the midline of the body; for the hand and arm, palm down and thumb next to the body (Chengalur et al., 2004, p. 671). Rotation is known as a body part in movement about its axis (Tayyari & Smith, 1997; Chengalur et al., 2004). These functions of the body also allow the hand, thumb, and fingers to couple, or grip, on tools that expand the capabilities of humans. Employee s can place a pinch grip or power grip on tools used for a job task (MacLeod, 1995; Chengalur et al., 2004). A pinch grip is when the fingers and thumb create compression of the object being held (Chengalur et al., 2004). This creates adequate friction to prevent the object from slipping out of the hand. A power grip is when the object is grasped by the thumb, palm, and fingers (MacLeod et al., 1990). The thumb and fingers should slightly overlap for a closed power grip. A power grip is four times stronger than a pinch grip, and a power grip reduces the pressure on tissues within the hand compared to a pinch grip (Chengalur et al., 2004). The motion required of the employee by the job task also has alternative types. Job tasks may require bodily functions to be performed for task completion in forms of static or dynamic forces (Chengalur et al., 2004). Static force of work is when a muscle is contracted for a duration, such as when an object must be held or a posture must be maintained for task completion (Chengalur et al., 2004, p. 114). An employee that simultaneously contracts a muscle while holding an object may experience localized muscle fatigue possibly leading to an injury or illness (MacLeod, 1995: Chengalur et al., 2004). Dynamic force of work is when work

25 25 takes place in motion (Tayyari & Smith, 1997). An employee that pushes or pulls during manual material handling experiences dynamic work that may lead to an injury or illness. Dynamic and static forces on the human skeletal system are generally calculated in a worst case scenario, determining the largest stresses and forces on the body as a result of the load on the body and the required body posture (Tayyari & Smith, 1997, p. 70). Limits of the human skeletal system exist as well as individual risk factors (Chengalur et al., 2004). Individual Employee Risk Factors Increased possibility of employee ergonomic-based injury and illnesses may be reduced by identifying individual employee risk factors (Chengalur et al., 2004). Individual risk factors that create susceptibility to ergonomic-based injury and illnesses include the following according to Chengalur (Chengalur et al., 2004, pp ): Preexisting arthritis Peripheral circulatory disorders Preexisting neuropathy History of smoking Reduced estrogen levels Excessive weight Small hand/wrist size New to the job Aggressive work methods Inefficient work methods requiring excess force application High personal stress level (Chengalur et al., 2004, pp )

26 26 Employees that have preexisting medical conditions are at elevated risks for developing ergonomic-based injuries and illnesses (Chengalur et al., 2004). The employment requirements may aggravate preexisting conditions creating an injury or illnesses within the employee. Larger forces exerted by the fingers, thumb, or palm may need to be generated by employees with small hand or wrist sizes in order to possibly perform various required job tasks (Chengalur et al., 2004). New employees may be at a greater risk of developing an ergonomic-based injury or illness due to the fact that the employee is unfamiliar with efficient and effective work methods. Additionally, new employees may need to take time to appropriately develop work methods, skills, and experience until performance up to department standards is achievable and the opportunity for ergonomic-based injury and illness is possibly decreased (Chengalur et al., 2004). However, the ability to predict the occurrence of MSDs in a specific worker based on the presence of [individual] risk factors is not even remotely possible (Chengalur et al., 2004, p.455). Advising on the increased risk as well as closely monitoring these individuals to possibly reduce ergonomic-based injury and illness is recommended (Chengalur et al., 2004). Identification of these risk factors and appropriate workstation design may reduce ergonomicbased injuries and illnesses (MacLeod, 1995; Tayyari & Smith, 1997; Chengalur et al., 2004). Whom to Design a Workstation For When designing a workstation, it must be designed for a large population of potential employees to utilize (Tillman & Tillman, 1991). Anthropometrics describes the human body s dimensions and characteristics for the population (Tayyari & Smith, 1997). Anthropometric data is available for people of different sexes and ages, and from different geographical regions of the world within published tables and figures (Tayyari & Smith, 1997, p. 41). In order to design a workstation for employees the workstation should fit a wide population of potential

27 27 employees, not just the currently employed (Tillman & Tillman, 1991; Chengalur et al., 2004). Human capabilities for height, strength, reach dimensions, clearance dimensions, and other factors differ between individuals of one sex, as well as between male and female (Chengalur et al., 2004). The physical differences of the potential employees highlight the importance of a work environment with variability that accepts a large percentage of that potential population from large too small. Chengalur (2004) states The goal in ergonomic design is to accommodate the largest percentage of the men s and women s distributions for the capability or measurement of concern (Chengalur et al., p. 30). Designing a workstation for the average dimensions of the population is inadequate for any individual that does not fit the average dimensions, which is a large population (Tayyari & Smith, 1997; Chengalur et al., 2004). Designing a workstation for both extremes, small and large, of the population can be extremely costly. A workstation designed for the smallest of people would be very costly to develop in order to also fit the largest of people (Tayyari & Smith, 1997). Designing for a range of the population is the most commonly utilized design philosophy. This excepted practice utilizes a typical range of the 5 th to 95 th percentile of the population. Such a design would be expected to accommodate 90% of the design population (Tayyari & Smith, 1997, p. 42). Utilizing this anthropometric data for design may achieve appropriate fit between the workstation and the employee (Roebuck, 1995; Tayyari & Smith, 1997; Chengalur et al., 2004). To achieve appropriate fit between the employee and the workstation Tayyari & Smith (1997) recommend a five step procedure. Step one defines the workstations potential user population. This step determines if a worldwide population, United States population, or selected population of people will be utilizing the workstation (Tayyari & Smith, 1997). Step two defines the proportion of the population the design will accommodate. This step establishes

28 28 the effective range of the design, and commonly utilizes 90% or 95% proportions of the population (Tayyari & Smith, 1997; Chengalur et al., 2004). Next, the third step of the series concludes the type of important body dimensions in the design, as well as if the dimension is a reach or clearance dimension. The fourth step determines the percentile values of the dimensions for the chosen proportion of the population from anthropometric tables (Tayyari & Smith, 1997, p. 58). Sources for anthropometric data include the 1988 anthropometric survey of U.S. army personnel, the National Aeronautics and Space Administration (NASA) Man-Systems Integration Standards anthropometric design data, as well as other privately funded anthropometric studies (Gordon, Churchill, Clauser, Bradtmiller, McConville, Tebbetts & Walker, 1988; Chengalur et al., 2004; NASA, 2008). The fifth and final step is to determine the type of clothing and personal protective equipment (PPE) worn by the users and make the relevant clothing allowances since clothing and PPE will increase or decrease reach and clearance dimensions (Tayyari & Smith, 1997, p. 58). These factors must be analyzed prior to designing a workstation in order to reduce or eliminate ergonomic-based risk factors. Workstation Design To design a workstation providing little to zero ergonomic-based risk factors with employee comfort and a high level of productivity is possibly an indication of utilizing the concept of ergonomics appropriately (Tayyari & Smith, 1997). The goal of proper ergonomicbased workstation design is to minimize the incompatibilities between the capabilities of workers and the demands of their jobs, with resulting increases in productivity, enhanced safety performance, and reduced overall cost (Tayyari & Smith, 1997, p. 127). This goal may be achieved by establishing the reach and clearance dimensions of the workstation. These dimensions are determined by combining anthropometric data of people, the required work

29 29 dimensions within the workstation, and understanding the behavior patterns of the employees (MacLeod, 1995; Roebuck, 1995; Tayyari & Smith, 1997). To utilize the data for the greatest impact a systematic approach to design is recommended. A systematic approach to effective ergonomic-based workstation design is a four step process described by Tayyari and Smith (1997). This system s first step is preparation. This step utilizes the anthropometric data, required work dimensions within the workstation, and human behaviors to assess the capabilities and limitations within the workstation (Tayyari & Smith, 1997). Identification of all feasible design alternatives is the second step (Tayyari & Smith, 1997, p. 134). This step evaluates the possible design alternatives by utilizing the collaborated data from step one to establish the design limitations. Evaluating the designs functional characteristics, the compatibility of the functional characteristics with design constraints and the reliability of the alternative designs under the expected conditions is an element of this step (Tayyari & Smith, p. 134). The third step to this systematic approach is Selection of the best design alternative (Tayyari & Smith, 1997, p. 134). The design alternatives are assessed on a number of features to choose the best alternative. These features include the economy of production; efficiency of operations; and ease of maintenance (Tayyari & Smith, 1997, p. 134). The fourth and final step is examination of the final alternative (Tayyari & Smith, 1997, p. 134). This step creates a system of ergonomic evaluation to monitor the ergonomic-based effectiveness of the design. Ergonomic Evaluation Evaluating employee exposure to ergonomic-based risk factors within a job task may lead to improvement of the employee s health and well-being (Tayyari & Smith, 1997). Ergonomic evaluation may be performed through quantitative, semi-quantitative, and qualitative analysis

30 30 methods (Chengalur et al., 2004). Quantitative methods of job task analysis require objective data that utilizes mathematical calculations to yield a quantitative result. Semi-quantitative methods for job task analysis rely on a mix of judgment data and/or easily obtained quantitative data (Chengalur et al., 2004, p. 100). Qualitative job task analysis methods collect data through observational techniques. Quantitative, semi-quantitative, and qualitative methods of analysis are conducted within active or reactive assessment approaches (Tayyari & Smith, 1997). The reactive ergonomics assessment usually follows an accident or injury which has prompted the investigation (Tayyari & Smith, 1997, p. 391). This type of assessment is concerned with finding the root cause of the accident or injury, resulting in an expensive process that is limited in success possibility. The employee has already been injured or an accident has occurred (Tayyari & Smith, 1997). A job hazard analysis and a rapid entire body assessment are examples of reactive ergonomic assessments. A proactive ergonomic assessment typically occurs in the planning or design stages of construction or development of the workstation (Tayyari & Smith, 1997). Proactive ergonomic assessments are performed to reduce or eliminate the ergonomic-based risk factors associated with the workstation in the future. Employee surveys as well as task analysis in the design or planning stages of development are examples of proactive ergonomic assessments (Tillman & Tillman, 1991; Tayyari & Smith, 1997). The goal of proactive task analysis is to reduce or eliminate ergonomic-based risk factors and to determine the necessary procedures within a workstation (Tillman & Tillman, 1991). Task analysis helps determine designs, training, and operating instructions to help the user do the task safely and efficiently (Tillman & Tillman, 1991, p. 59). Task analysis is a qualitative form of analysis (Chengalur et al., 2004). A systematic approach to task analysis assists in

31 31 determining the critical and noncritical tasks the employee within the workstation is performing (Tillman & Tillman, 1991). A critical task is a task that can create potential harm to an employee, and a noncritical task is one that does not have the potential to cause harm or injury to an employee. Systematic task analysis is used to define the equipment used to do each task, stimulus initiating the task, human response to the task, task feedback, task performance criteria, and the task environment (Tillman & Tillman, 1991, p. 70). Additionally, systematic task analysis determines the tasks that need improvement and tasks that do not (Tillman & Tillman, 1991). This form of analysis produces accountability for responsible individuals, improvements for the design of the workstation, proper training requirements, and possibly improvement of the current procedures to complete the requirements of the job. Systematic task analysis is useful for identifying potential areas that may affect employee injury and illness (Tillman & Tillman, 1991). Employee risk perception survey. An additional form of qualitative analysis, which is a proactive ergonomic assessment, is an employee risk perception survey (Tayyari & Smith, 1997; Stanton et al., 2005; O Toole & Nalbone, 2011). The purpose of an employee risk perception survey is to gather employee beliefs, or perceptions, from questions based on safety factors of the job (O Toole & Nalbone, 2011). These answers, or employee beliefs of the job, are then compared to the job safety program or process (O Toole & Nalbone, 2011). This type of survey is used as an indicator to determine safety program effectiveness. If the employee believes the safety program performs one way, and management perceives it as another, then additional input into the safety system is needed. Additionally, the employee s understanding of risks that they are required to work within is evaluated (Tayyari & Smith, Stanton et al., 2005). A well developed survey will keep its participants anonymous and a risk perception survey will

32 32 ask yes or no questions (Petersen, 1993). This survey can be distributed companywide or for any type of specific job task, but a specific form of evaluation for lifting tasks is available (Tayyari & Smith, 1997; Stanton et al., 2005). Revised NIOSH lifting equation. To accurately analyze and determine the potential for employee injuries and illness regarding lifting tasks, a National Institute for Occupational Safety and Health (NIOSH) lifting equation can be utilized (Waters, Putz-Anderson & Garg, 1994). The revised NIOSH lifting equation was established though biomechanical, physiological, and psychophysical criterion (Waters et al., 1994, p. 3). The original NIOSH lifting equation published in 1981 was revised for consideration of additional components of lifting tasks such as asymmetrical lifting and quality of hand-container couplings as well as a larger range of work durations and lifting frequencies than did the 1981 equation (Waters et al., 1994, p. iv). Studies were performed to determine the significance of six various forms used during lifting and lowering tasks, and the results of those studies influence the revised NIOSH lifting equation s factors (Waters et al., 1994). The revised lifting equation is a tool that was developed to potentially prevent work-related lower back pain and disability (Waters et al., 1994, p. 3). This equation separates the first and second half of the lift. The first section of the lift is known as the origin, and the second half of the lift is known as the destination (Waters et al., 1994). This provides the potential to identify which part of the lift creates the most significant risk to affect employee health and well-being. Additionally, this revised equation establishes a quantitative value for the two sections of the lift (Waters et al., 1994). The revised lifting equation is based on the assumptions that the following does not occur during the lifting or lowering actions of the task (Waters et al., 1994, pp ):

33 33 Lifting/lowering with one hand, lifting/lowering for over 8 hours, lifting/lowering while seated or kneeling, lifting/lowering in a restricted work space, lifting/lowering unstable objects, lifting/lowering while carrying, pushing or pulling, lifting/lowering with wheelbarrows or shovels, lifting/lowering with high speed motion, lifting/lowering with unreasonable foot/floor coupling, lifting/lowering in an unfavorable environment (pp.11-12). These assumptions if experienced, with one or more, may create or aggravate low back pain but are not included in the revised equation (Waters et al., 1994). These assumptions formulate the opportunity to create a quantitative equation with the six variables. The six variables include horizontal multiplier, vertical location dimension, distance dimension, asymmetric measurement, frequency of the task, and hand grip multipliers. A load constant (LC) multiplier is also used but was established by NIOSH as a constant for the equation and cannot be changed (Waters et al., 1994). These multipliers are then used within the revised NIOSH lifting equation to create a recommended weight limit (RWL) for the task (Waters et al., 1994). The RWL is defined for a specific set of task conditions as the weight of the load that nearly all healthy workers could perform over a substantial period of time (Karwowski & Marras, 1999, p. 1038). The RWL is calculated on a multiplicative model that provides a weight for each of the six task variables. The weightings are expressed as coefficients that serve to decrease the load constant, which represents the maximum recommended load to be lifted under ideal conditions (Waters et al., 1994, p. 12). The horizontal multiplier (HM) takes a point directly below the center location of the hands when grasping the object to be lifted, and measuring from this point to the center point between the ankle bones. The distance between the two points is considered

34 34 (H) within this equation (Waters et al., 1994). When this distance is less than 10 inches, then the measurement is set at 10 inches within the equation. The HM equation is (10/H). The vertical multiplier (VM) utilizes the measurement of the center point between hands above the floor at the beginning of the lift, as well as the center point between the hands above the floor at the end of the lift (Waters et al., 1994). This distance at the beginning and end of the lift is considered (V) for this equation. The multiplier utilizes 30 inches as the favorable lift height. The equation for calculating the vertical multiplier is (1-(.0075 [V-30])) (Waters et al., 1994, p. 17). The distance multiplier (DM) defines the distance the object is lifted from the beginning of the lift to the end of the lift. This distance is considered (D) in the equation (Waters et al., 1994). The equation for the DM is (.82 + (1.8/D)) (Waters et al., 1994, p. 19). The asymmetry multiplier (AM) refers to a lift that begins or ends outside the mid-sagittal plane (Waters et al., 1994, p.19). This defines and measures the amount of rotation about the center axis of the body. A diagram of reference about this measurement can be found in Appendix A. The angle of the asymmetry is defined as the angle between the asymmetry line and the mid-sagittal line (Waters et al., 1994, p. 21). The asymmetry line is the line between the center point between the ankle bones and the center point between the hands at the beginning and ending points of the lift. The mid-sagittal line is defined as the line passing through the mid-point between the inner ankle bones and lying in the mid-sagittal plane, as defined by the neutral body position (Waters et al., 1994, p. 21). This angle of asymmetry is considered (A) in the NIOSH lifting equation. The equation for the asymmetric multiplier is (1 (.0032A)) (Waters et al., 1994, p.21). The frequency multiplier (FM) is calculated by determining the employee movements including the number of lifts per minute, the duration of the lifting activity, and the height of the lift from the floor (Waters et al., 1994). The corresponding value of the FM can be found on the frequency

35 35 multiplier table, in Table 1 (Waters et al., 1994, p. 26). The coupling multiplier (CM) determines the nature of the hand-to-object coupling or gripping method (Waters et al., 1994, p. 28). This multiplier uses the terms good, fair, and poor to establish a coupling classification. A good coupling is defined as an object that has hand-holds, handles, or a comfortable grip on the object (Waters et al., 1994). A fair coupling is defined as an object that has unfavorable hand-holds, handles, or a grip that establishes the hand flexed about 90 degrees (Waters et al., 1994, p. 29). A poor coupling classification is when an object or containers of less than optimal design or loose parts or irregular objects that are bulky, hard to handle, or have sharp edges (Waters et al., 1994, p. 29). An example of a poor coupling classification is lifting non-rigid bags, such as a bag of sand (Waters et al., 1994). The CM also utilizes the height of the lift as a factor. The CM table establishes the corresponding values, and can be found in Table 2 (Waters et al., 1994, p. 31). The RWL is calculated as (Waters et al., 1994, p.12): RWL = (LC) X (HM) X (VM) X (DM) X (AM) X (FM) X (CM) An additional calculation to help the NIOSH lifting equation evaluate a lifting task is the lifting index (LI) (Waters et al., 1994). The LI estimates the potential physical stress of the employee while performing the lifting task. The LI is calculated as the load weight (L) over the RWL. The load weight is defined as the weight of the object that is being lifted during the task. This establishes the ratio of the current object weight to the recommended weight limit (Waters et al., 1994). As the LI increases as does the estimated stress on the employee. The LI is useful in identifying potentially hazardous lifting jobs or to compare the relative severity of two jobs for the purpose of evaluating and redesigning them (Waters et al., 1994, p. 34). The revised NIOSH lifting equation is a useful tool for determining specific tasks of the job that may force

36 36 potential stress on an employee during a lifting task, and a useful tool is available to help evaluate non-lifting tasks. REBA. A rapid entire body assessment (REBA) evaluates employee tasks through a semi-quantitative means to determine the level of risk and urgency with which action should be taken (Stanton, Hedge, Brookhuis, Salas, & Hendrick, 2005, p. 8-1). This type of evaluation assesses the whole body. The REBA collects information about the employee s body movement statically and dynamically, repetitive action amounts, hand coupling, body posture, and forces exerted to perform the task (Hignett & McAtamney, 2000; Stanton et al., 2005). Through this collection of data, the REBA generates a finalized score indicating the type of action needed to take to potentially eliminate or reduce ergonomic-based risks to the employee. To determine a final REBA score, the assessment utilizes a series of six steps (Hignett & McAtamney, 2000; Stanton et al., 2005). The first step is to observe the tasks required of the job on the employee, to find the critical tasks. The second step is to select postures for assessment from the critical tasks identified in step one (Stanton et al., 2005). When selecting the critical posture(s), the deciding criteria should be reported in the results and recommendations portion of the assessment. The third step of the REBA is to score the postures according to the REBA score sheet (Stanton et al., 2005). The REBA score sheet can be found in Appendix B. The REBA scoring sheet utilizes two groups, Group A and Group B, according to established body part scores. Group A includes the trunk, neck, and legs, while Group B includes the upper arms, lower arms, and wrists (Hignett & McAtamney, 2000; Stanton et al., 2005). The scoring is based on the employee s body posture position(s) during the identified critical task of the body s trunk, neck, legs, upper arms, lower arms, and wrists (Hignett & McAtamney, 2000; Stanton et al., 2005). For the arms

37 37 and wrists the left and right sides of the body are both analyzed, and the worse of the two is utilized for the score. This is performed to assess for different circumstances for each side during a task. The body s trunk, neck, legs, upper arms, lower arms, and wrist positions experienced during the identified critical task have favorable positions that have a desired score of one, as shown in Appendix B (Hignett & McAtamney, 2000; Stanton et al., 2005). If the body s trunk, neck, legs, upper arms, lower arms, and wrist positions experienced during the critical tasks are not within the defined favorable positions of the REBA body part diagram, then the corresponding score of the body part s position will be recorded on the REBA scoring sheet. The scores then from the body part diagrams are processed in step four (Hignett & McAtamney, 2000; Stanton et al., 2005). Group A s scores are recorded on table A of the REBA document. Table A identifies the corresponding group s value of risk and records it on the REBA scoring sheet. Group B s scores are recorded on the REBA scoring sheet and then placed on table B of the REBA document (Hignett & McAtamney, 2000; Stanton et al., 2005). The corresponding table B value is then recorded on the REBA scoring sheet. The load or force score is then added to the Group A s cumulative score. The load or force is calculated from the weight or force exerted to perform the task the employee is performing (Hignett & McAtamney, 2000; Stanton et al., 2005). The favorable weight is below eleven pounds and values are added for greater weights increasing the score. The coupling score is added to Group B s collective score (Hignett & McAtamney, 2000; Stanton et al., 2005). The coupling score is determined much like the revised NIOSH lifting equation s coupling score. The coupling scores decrease from good, to fair, to poor, finally to unacceptable (Hignett & McAtamney, 2000; Stanton et al., 2005). A good coupling is one that fits the hand well with a power grip (Hignett & McAtamney, 2000; Stanton et al., 2005). A fair coupling is an acceptable hold but one that could be improved. A

38 38 poor coupling is a possible hold but is not acceptable (Hignett & McAtamney, 2000; Stanton et al., 2005). An unacceptable coupling is one that is awkward and forces the employee to utilize an unsafe grip or one that uses other body parts to hold the object from slipping. Group A and Group B s final scores with load/force and coupling are recorded in Score A and Score B locations (Hignett & McAtamney, 2000; Stanton et al., 2005). Score A and Score B are then entered into Table C, and a single score is read off. This is score C (Stanton et al., 2005, p. 8-3). The activity of the work is also an added factor in the REBA. The activity score factors the present static forces, repetitive actions, and significant posture changes, or lack thereof of each factor (Hignett & McAtamney, 2000; Stanton et al., 2005). Next, the fifth step of six is to calculate the final REBA score. This is where the C score is added to the activity score for a final REBA score. The final REBA score correlates to a risk and action level (Hignett & McAtamney, 2000; Stanton et al., 2005). The risk level, a number from1-12, determines the risk to the employee from performing the job task, and the action level is the level of recommended change. The risk levels range from negligible, to low, medium, high, and finally very high (Hignett & McAtamney, 2000; Stanton et al., 2005). The action levels array from none necessary, to may be necessary, necessary, necessary soon, and necessary NOW (Hignett & McAtamney, 2000; Stanton et al., 2005). The sixth and final step is to verify the action level of the REBA matches the environment the assessment took place within. To appropriately measure the exposure to ergonomic-based risk factors during evaluation, ergonomic instrumentation may be utilized (Hignett & McAtamney, 2000; Stanton et al., 2005). Ergonomic Instrumentation To quantify ergonomic-based data within the NIOSH lifting equation as well as the rapid entire body assessment, measurement tools, or instrumentation, may be utilized (Roebuck, 1995).

39 39 Angles, distances, and weights must be quantified for the evaluation techniques to develop accurate results (Hignett & McAtamney, 2000; Stanton et al., 2005). Diarthrotic joints are the pivot points between two bones, and precise measurement of angles is necessary for an accurate REBA result (Tayyari & Smith, 1997; Hignett & McAtamney, 2000; Stanton et al., 2005). The asymmetric angles required of a job task must be accurately quantified to provide the NIOSH lifting equation with valuable data (Waters et al., 1994). To meet the requirements of these evaluation techniques a manual goniometer, tape measure, and weight scale are useful instruments of measurement (Roebuck, 1995). The manual goniometer may be useful to determine the posture of an employee as well as the range of joint during a critical task. Therefore, the manual goniometer may help determine the postural demands of the job (Roebuck, 1995). A tape measure can be a useful tool to quantify the distance requirements of a task. The instrument can determine a workstations clearance and reach dimensions, as well as specific measurements necessary to determine the NIOSH lifting equation s specific multipliers (Waters et al., 1994; Tayyari & Smith, 1997). An additional instrument to measure the weight or force of an object can be a weight scale. A scale may quantify the force necessary to be exerted by an employee during a lifting or lowering task in order to complete the task. Following an evaluation and determining areas that need improvement, controls may be used to beneficially alter ergonomic-based areas of risk to employees (MacLeod et al., 1990; Tayyari & Smith, 1997; Chengalur et al., 2004). Ergonomic Controls When ergonomic-based risk factors are identified, controls in the form of processes, procedures, or method changes may reduce or prevent risk factors (Friend & Kohn, 2007). Three control approaches are available to beneficially alter ergonomic-based risks to employees

40 40 associated with required tasks of a job (Tayyari & Smith, 1997; Chengalur et al., 2004; Friend & Kohn, 2007). Engineering controls, administrative controls, and personal protective equipment (PPE) can potentially minimize or eliminate ergonomic-based risks. Engineering controls are the considered most effective in reducing risk factors due to the fact that they eliminate the manual requirements of the job by using hoists, cranes, manipulators, chutes, conveyors, or lift trucks, or through mechanization or automation (Waters et al., 1994, p. 48; Tayyari & Smith, 1997; Chengalur et al., 2004). Put another way, engineering controls consist of work methods and or tool designs that eliminate the risk factor altogether (Chengalur et al., 2004, p. 490). Mechanical hoists or cranes that lift and move materials that eliminate or reduce employee manual material handling, are examples of an engineering control. When engineering controls are not feasible, administrative controls may be put in place (MacLeod et al., 1990; Tayyari & Smith, 1997; Chengalur et al., 2004; Friend & Kohn 2007). Administrative controls improve current processes or procedures, increase current employee training, and potentially influence pay scales and incentives (Tayyari & Smith, 1997; Chengalur et al., 2004; Friend & Kohn 2007). Examples of administrative controls include exercise programs that improve employee health and well-being, as well as implemented stretching techniques during work that may help prevent back disorders (MacLeod et al., 1990; Chengalur et al., 2004). Lastly, personal protective equipment (PPE) is the least reliable approach to reducing risk factor exposure (Chengalur et al., 2004, p. 491; Friend & Kohn, 2007). Unlike a process change or mechanical hoist to reduce ergonomic-based risk factors to employees, PPE does not change the environment (Chengalur et al., 2004; Friend & Kohn, 2007). Simply, PPE is considered the last line of defense because the barrier separating the employee from the health

41 41 hazard must be worn correctly and consistently (Friend & Kohn, 2007, p. 123). Ergonomicbased PPE provides the user with hand and arm protection, as well as protective hand creams (Tayyari & Smith, 1997). Palm padded gloves have the potential to protect the palm against impact and vibration while maintaining the dexterity in manipulation using the fingertips (Tayyari & Smith, 1997, p. 184). Engineering controls are considered the preferred method due to the fact that PPE and administrative controls fail to eliminate the risks from the workplace (Tayyari & Smith, 1997; Chengalur et al., 2004; Friend & Kohn, 2007). Even with the availability of ergonomic-based evaluation techniques and ergonomic instrumentation, back injuries in the workplace are occurring according to the BLS (BLS, 2011b). Cost Analysis of Back Injuries In 2010, the Bureau of Labor Statistics (BLS) injury and illness report claimed that sprains, strains, and tears accounted for 40 percent of total injury and illness cases requiring days away from work (BLS, 2011b). Of this 40 percent of total injuries and illnesses, 36 percent of these reported injuries and illnesses occurred due to injuries and illnesses of the back. Additionally, 346,400 MSDs were reported and back injuries accounted for nearly half of the MSD cases and required a median of 7 days to recuperate (BLS, 2011b, p. 6). This calculates to approximately 173,200 employee back injuries within the United States in 2010 (BLS, 2011b). In the state of Washington, an average workers compensation back injury claim costs $ to the organization (WSD, 2011). This equates to roughly $1.5 billion workers compensation direct costs when calculated nationally for only back injuries. It is estimated that indirect costs exceed direct costs by a factor of four (MacLeod et al., 1990). Therefore, indirect costs to an organization of each back injury are estimated at $33,868 (WSD, 2011; MacLeod et al., 1990). Accordingly, indirect costs are approximately $6 billion

42 42 for back injuries alone within the United States. Roughly 131,359,000 employees work within the United States according to the BLS (2012b). This large workforce creates the opportunity for ergonomic-based back injuries and illnesses. To reduce annual back injuries for an organization by two may potentially save the organization $16,934 in direct costs and $67,736 in indirect costs (WSD, 2011). Reducing back injuries may be possible by evaluating workstations for ergonomic-based risk factors and establishing controls to reduce the employee risk to developing ergonomic-based injuries and illnesses (MacLeod, 1995; Tayyari & Smith, 1997; Chengalur et al., 2004; Stanton, 2005).

43 43 Chapter 3: Methodology This study s purpose was to perform an ergonomic-based analysis of the widget production line to determine the extent of the potential ergonomic-based issues. The problem of the study was company XYZ s presence of ergonomic-based risk factors on the widget production line could potentially affect employee health and well-being. This chapter will discuss the techniques used to evaluate the widget production line for employee ergonomicbased risk factors through the discussion of research methods, instrumentation of research, procedures utilized to conduct research, and research data analysis. Research Methods The study was established to determine the employee exposure to ergonomic-based risk factors within the widget production line at company XYZ. The study attempted to perform this utilizing a series of evaluation techniques determined through the review of applicable literature. The review of literature expressed quantitative, qualitative, and semi-quantitative research methods of pro-active and reactive ergonomic-based analysis (Tayyari & Smith, 1997; Chengalur et al., 2004). Several methods of analysis were used to determine employee exposure to ergonomic-based risk factors. The first research method utilized to evaluate the employee potential exposure to ergonomic-based risk factors was the Rapid Entire Body Assessment (REBA). The REBA was used to establish and determine the present potential ergonomic-based risk factors to the employee. The method is performed while watching a competent employee perform a job task. The activities the employee performs are then recorded on the REBA worksheet. This method collects information about the employee s body movement statically and dynamically, repetitive action amounts, hand coupling, body posture, and forces exerted to perform the task.

44 44 Following this method, the revised National Institute for Occupational Safety and Health (NIOSH) lifting equation was utilized. This was used because of its quantitative analysis method that evaluates the weight of the test gauge to the recommended weight limit (RWL) of the task. Additionally, this determines ergonomic-based risks of the job task, providing valuable information to the study. The third evaluation technique to determine potential employee exposure to ergonomicbased risk factors was an employee risk perception survey. The risk perception survey can be found in Appendix C. A risk perception survey was used to gather employee beliefs on safety factors of the job. The survey responses provided information, or data, from the questions asked of the employees. The results of these methods of evaluation can be found in the following chapter 4, results of the study. The final evaluation strategy will provide a cost effectiveness of a proposed control to reduce or eliminate the ergonomic-based risks present on the widget production line at company XYZ. This will provide valuable information to the organization that will compare two values. One value will be the cost of a proposed control, or job redesign, to reduce or eliminate the ergonomic-based risks. The second value will be $16,934 determined through the review of literature. This value is the average cost to an organization of two lower back injuries annually. Sample Selection One subject was observed and analyzed for the revised NIOSH lifting equation and the REBA. These two research methods, or surveys, were conducted while observation of the individual occurred. The observation took place during the work week within normal working hours on the widget production line. The individual selected was the only individual working on

45 45 the widget production line at that time of day. Permission to observe was granted and zero constructive interaction with the individual to perform the work occurred. The risk perception survey was provided to the three employees who routinely worked on the widget production line at company XYZ as their primary job. This method for the sample is utilized due to the fact that a limited population of employees perform tasks within the widget production line at company XYZ. Instrumentation of Research The above methods of evaluation were chosen due to their ability to supply valuable information to the study which attempts to answer the proposed questions of the study. The REBA and revised NIOSH lifting equation both helped to clarify and answer question one of the study. These two instruments of ergonomic-based evaluation determined the potential impact of employee health and well-being from working at company XYZ on the widget production line. The employee risk perception and symptom survey aided to answer question two. This survey determined the risk perceptions of employees performing the job task on the widget production line at company XYZ. Potential recommended control costs for the risks helped to answer question three. These costs as well as the cost analysis of back injuries section of the review of literature determined the cost effectiveness of the controls in preventing overexertion injuries pertaining to the lower back. The tools utilized for the study included a manual goniometer, a tape measure, and a weight scale. These provided the ability to measure angles, distances, and weights to establish values within the REBA and revised NIOSH equation as examined in the review of literature. Specific procedures to completing these methods were used.

46 46 The cost effectiveness comparison will calculate the total current value of implementing a control to reduce or eliminate two injuries or illnesses pertaining to the lower back. Microsoft Excel will be utilized to provide a spreadsheet with values to calculate the values, control cost, and a three year employee lower back injuries and illness cost to the organization. Procedures Utilized to Conduct Research To conduct the revised NIOSH lifting equation, the REBA, and the employee symptom survey a series of steps for each were utilized. REBA. The REBA research method followed the recommended Hignett & McAtamney (2000) six step series as documented in the review of literature chapter. The first step of the series is to observe the tasks required of the job on the employee, to find the critical tasks. Once identified, the critical task was recorded. The second step is to select postures for assessment from the critical tasks identified in step one (Stanton et al., 2005). The posture of the critical task was selected for research. Next, the third step scores the postures according to the REBA score sheet (Stanton et al., 2005). The posture scores were recorded on the REBA sheet. Following the third step, the scores from the body part diagrams are processed in step four (Hignett & McAtamney, 2000; Stanton et al., 2005). The body part scores from the tables were then recorded on the REBA sheet. Then, the fifth step of six is to calculate the final REBA score. The final REBA score from was then calculated on the sheet. The sixth and final step is to verify the action level and final score of the REBA match the environment the assessment took place within (Hignett & McAtamney, 2000). NIOSH. This evaluation was conducted on the lifting and lowering task on the widget production line at company XYZ. This research method followed the established calculations to determine the multiplicative factors based on the actions of the employee during the task as

47 47 documented in the review of literature, the following steps discuss how this occurred. The first step measured the horizontal multiplier (HM), vertical multiplier (VM), and distance multiplier (DM) required distances as expressed in the review of literature with a tape measure (Waters et al., 1994). The asymmetry multiplier (AM) was measured with a manual goniometer. The coupling multiplier (CM) was determined by corresponding the hand coupling manner required of the employee during the task, with the description on the coupling multiplier table, Table 2 (Waters et al., 1994). The frequency multiplier (FM) was calculated by counting the repetitions of the task performed over an eight hour period of work, and referencing this amount on the frequency multiplier table, Table 1. These values were recorded and placed within the following equation (Waters et al., 1994, p. 12): RWL = (LC) X (HM) X (VM) X (DM) X (AM) X (FM) X (CM) This equation provided a recommended weight limit for the job task. The RWL was then utilized within the lifting index calculation of load weight (L) over the RWL for the origin and destination sections of the lift. Risk perception survey. The employee risk perception survey was established on Qualtrics.com, an online survey website that provides the employees results anonymously. The survey link to Qualtrics.com was sent via to the supervisor of the three employees that routinely work on the widget production line at company XYZ. The supervisor provided a computer and survey link to the individuals. The individuals then completed the online survey. The completed surveys were stored online. The results to the survey s questions were then evaluated. Cost effectiveness comparison. The cost effectiveness comparison will take the average injury payment, the number of lower back injuries or illnesses reduced or eliminated annually,

48 48 average inflation rate of ten percent, ROI factor of eleven percent, the control life s expectancy of five years, and the current value of future savings values cost of the control. These values will provide a final current value of savings for the cost effectiveness comparison. This will identify if the control will or will-not be a sound financial investment to the organization. Research Data Analysis The REBA, revised NIOSH lifting equation, and the employee risk perception survey results were analyzed to determine employee ergonomic-based risk factor exposure and perception. The cost effectiveness comparison results determined the financial effectiveness of a control to reduce or eliminate ergonomic-based risk factors on the widget production line. The REBA and revised NIOSH lifting equation results were analyzed based on the scales provided by REBA and NIOSH. The REBA scale determined the risk level between negligible and very high. The final score of the REBA worksheet quantified the risk level. Additionally, the REBA determined the action level required to control the risks within the task. The revised NIOSH lifting equations origin and destination RWL s and LI s were evaluated. This evaluation of the revised NIOSH lifting equation data was performed by determining the quantified LI value given to both the origin and destination regions of the lift. The evaluation provided an understanding of the ergonomic-based lifting and lowering risks the employee experiences during the job task. The employee risk perception survey evaluated each question s answer to determine the employee risk perception of the task as well as safety program effectiveness. The results, or answers, to these questions will be compared to the results of the REBA and revised NIOSH lifting equation to provide an understanding of employee risk perception.

49 49 The cost effectiveness comparison provided data to determine the current value of savings of implementing an engineering control. This value aided the organization to determine if the control was worth the investment at the current time. The following chapter provides the results of the study.

50 50 Chapter 4: Results of Study The purpose of this study was to perform an ergonomic-based analysis of the widget production line to determine the extent of the potential ergonomic issues at company XYZ, and determine if ergonomic-based risk factors on the widget production line could potentially affect employee health and well-being. The questions that drove the study included; 1) perform an ergonomic analysis of the widget production line to determine/identify ergonomic risk factors that impact employee health and well-being; 2) determine the risk perception of employees performing the job; and finally 3) determine the cost effectiveness of a control that prevents overexertion injuries pertaining to the lower back. The study consisted of four parts that helped to answer the questions of the study. These included a REBA (rapid entire body assessment), a revised NIOSH (national institute for occupational safety and health) lifting equation calculation, an employee risk perception survey, and a cost analysis of a control that may prevent overexertion injuries pertaining to the lower back. The results of four sections are discussed hereafter. Question #1: Perform an ergonomic analysis of the widget production line to determine/identify ergonomic risk factors that impact employee health and well-being According to literature reviewed in chapter two, an ergonomic analysis was performed on the widget production line to determine/identify ergonomic risk factors that impact employee health and well-being. The ergonomic analysis consisted of a revised NIOSH lifting equation calculation and a REBA assessment. The revised NIOSH lifting equation presented the study with a pair of quantitative values. These values were in the form of ergonomic-based risk on the task of lowering and lifting the

51 51 test gauge into the aerospace engine and engine parts production machine. Various measurements were taken of the employee s actions during the lifting and lowering task. Measurements were taken at the origin and the destination parts of the lifting and lowering task. The hand s horizontal origin was 21 inches and the vertical origin distance was 39 inches. The hand s horizontal destination was 30 inches and the vertical destination was 25 inches. This resulted in a vertical distance of negative fourteen inches. The asymmetric angle of the employee at the origin and destination was also measured. The origin asymmetric angle was five degrees and the destination asymmetric angle was 5 degrees. The frequency value was calculated at one from Table 1. This was due to the fact that the frequency rate was less than 0.2/minute. The coupling of the test gauge resulted in a value of 1.0. This was calculated from Table 2, the coupling was rated as good. These measurements and values then were utilized in the equation. The revised NIOSH lifting equation utilized the measurements and values from above to calculate origin and destination RWL s (recommended weight limit). The origin RWL was determined to be The destination RWL was calculated to be These values were then used to determine the LI (lifting index). The LI also calculated an origin and destination value. The origin value for the task was calculated at This result indicates a moderate risk of possible injury or illness to the employee according the review of literature. The destination value was determined to be According to the review of literature, this is above the acceptable level of 1.0, potentially exposing the employee to high levels of risk. The full revised NIOSH lifting equation ergonomic evaluation can be found in Appendix D.

52 52 Additional ergonomic analysis utilized to perform an ergonomic analysis of the widget production line to determine/identify ergonomic risk factors that impact employee health and well-being was the Rapid Entire Body Assessment. The REBA assessment provided a semiquantitative value for the posture of the employee while lowering/lifting the test gauge into a production machine. The value was correlated to the surveyed posture of the employee. The following employee body parts were assigned values: Trunk Neck Legs Upper Arms Lower Arms Wrists During the survey specific body parts were assigned a value. These specific body parts include the list above. The trunk was surveyed and noted that the employee flexed the trunk greater than 60 degrees. This angle on the REBA assessment resulted in a trunk value of four. The employee neck was flexed at greater than 20 degrees. Additionally, the neck was tilted to one side. Therefore the cumulative REBA score for the neck was given a score of three. The employee legs were bilateral weight bearing; however, the legs were flexed at an angle greater than 60 degrees. Thus, the leg posture value was a three. Additionally, the employee was lifting/lowering a 31 pound test gauge. These scores were place on Table A of the REBA worksheet. The results Table A value was an eight. Additionally, the test gauge weighed 30 pounds. This lifting/lowering action results in an additional two point rate awarded to the Table

53 53 A value. This is due to the test gauge weighing greater than 22 pounds according to the REBA assessment. The final value of the trunk, neck, and legs resulted in a ten. The upper arm, lower arm, and wrist positions were also quantitatively valued on the REBA worksheet. The upper arm was flexed at greater than 90 degrees resulting in a REBA worksheet score of four. The lower arm position was flexed greater than 100 degrees. Therefore, this resulted in a REBA worksheet lower arm value of two. The wrist position was flexed at ten degrees producing a value of one. The results of the upper arm, lower arm, and wrists were then placed on Table B of the REBA worksheet. These values produced a Table B score of six. The coupling score of the test gauge was rated at good or the coupling consisted of a well fitting handle and mid range power grip. This coupling added no additional value to the Table B score. The next step in the REBA process was to find the Table C score. The Table A and Table B values were placed on Table C of the REBA worksheet. The Table A value of eight and the Table B value of six resulted in a Table C score of eleven. The final step of the REBA worksheet was to calculate the Activity Score and add it to the Table C score. The employee held 1 or more body parts for longer than 1 minute (static), thus the activity score of one was added to the Table C score of eleven. This resulted in a final REBA score of twelve. Therefore, the REBA assessment concluded that the employee is at a very high risk of injury/illness and change should be implemented into the job task. The full REBA ergonomic evaluation can be found in Appendix E. Question #2: Determine the risk perception of employees performing the job The employee risk perception survey provided qualitative analysis results of the risk perception of the respondents. The questions asked to the respondents were utilized to determine

54 54 the risk perception of employees who perform the widget production line workstation job. The following table includes the respondent s answers: The results to these questions yielded yes, no, and other specific answers. The survey revealed that the respondents have not been injured while working on the widget production line. Management has been spoken to by the employees regarding the lifting or lowering of the test gauge on the widget production line. This indicates that the employees are possibly aware of the difficulties of working on the widget production line. A job safety assessment has been

55 55 performed on the widget production line also according to the respondents. A single respondent was involved in the job safety assessment. This indicates that the organization may know of the difficulties presented to employees on the widget production line. It also indicates that the employee perceptions of the safety assessment may deem the widget production line as a safe place to work. Additionally, two of three respondents indicated that the widget production line tasks could not be improved. This alludes to the fact that the respondents believe there is no way to improve the workstations job tasks. Furthermore, all respondents feel the widget production line workstation is safe and that the workstation fits them. According to the REBA and revised NIOSH lifting equation, this is not true. This provides data that the three respondent perceptions of risk on the widget production line do not correlate to the actual risks determined by the REBA and revised NIOSH lifting equation. A copy of the original survey can be found in Appendix C. Question #3: Determine the cost effectiveness of a control that prevents overexertion injuries pertaining to the lower back To determine the cost effectiveness of a control that prevents overexertion injuries pertaining to the lower back, cost effectiveness was calculated utilizing average injury payment, average inflation, ROI factor, the control life s expectancy, and the current value of future savings values. The value of an average payment for one back injury of $8,467 was utilized and determined from the review of literature. This would be in the form of direct costs to the organization according to WSD (2011) from the literature review. Therefore, with two annual back injuries direct costs to the organization are expected to be $16,934. The average inflation factor was set at 10 percent for this calculation and the discount factor was set at 11 percent. These factor values were predetermined within Chapter 3 to illustrate the ROI concept, and were not established within the Review of Literature or from company XYZ. The engineering control

56 56 life s expectancy was set at three years with a cost of $ The current test gauge consists of two handles that create the power grip and an engineering control that simply replaces the grips with two hooks to allow the overhead crane to lower the test gauge onto the production part would be sufficient. The total present value of injury payments resulted in $50, with a cost of control of $ This results in a current value of savings for the control of $49, The cost effectiveness comparison evaluation can be found in Appendix F. The following chapter will utilize the results of the study to make recommendations and conclusions of the study.

57 57 Chapter 5: Summary, Conclusions and Recommendations The purpose of this study was to perform an ergonomic-based analysis of the widget production line to determine the extent of the potential ergonomic issues at company XYZ, and determine if ergonomic-based risk factors on the widget production line could potentially affect employee health and well-being. This chapter provides three district sections that describe information of the study. This chapter includes a study summary, a study conclusion, and study recommendations. The results of these three sections are discussed hereafter. Summary Restatement of the problem. Company XYZ s presence of ergonomic-based risk factors on the widget production line could potentially affect employee health and well-being. Methods and procedures. Widget production line employees were utilized throughout the study. Ergonomic tools utilized included the revised National Institute for Occupational Safety and Health (NIOSH) lifting equation, the Rapid Entire Body Assessment (REBA), and a risk perception survey were utilized. These tools quantitatively, semi-quantitatively, and qualitatively analyzed the employee ergonomic-based risk. The methodology and procedures for the study followed the recommendations found in the review of literature for the ergonomic tools. Major findings. The results of the study indicate the potential for ergonomic-based employee injury or illness according to the REBA and revised NIOSH lifting equation. The final REBA risk level concluded that the employee is at a very high risk of injury/illness. The revised NIOSH lifting equation lifting index value indicates that the widget production line is potentially exposing the employee to high levels of ergonomic-based risk.

58 58 The ergonomic-based risk perception survey distributed to employees on the widget production line indicated that respondent beliefs on the risk levels they experience are low. According to the results, the respondents feel the widget production line workstation is safe and that the workstation fits them. According to the REBA and revised NIOSH lifting equation, the workstation exposes the employees to high levels of ergonomic-based risk due to the fact that the workstation does not fit them. The ergonomic analysis and the risk perception survey provide data that the three respondent perceptions of risk on the widget production line do not correlate to the actual ergonomic-based risks determined by the REBA and revised NIOSH lifting equation. Conclusions The ergonomic-based analysis performed during this study determined that an employee performing job tasks on the widget production line workstation experience s high levels of ergonomic-based risks. The revised NIOSH lifting equation s results indicate a need to implement change due to the large Lifting Index (LI) values. The REBA worksheet s results indicate a very high ergonomic-based risk level that may cause employee injury or illness. The results of the revised NIOSH lifting equation and the REBA worksheet both indicate a high level or ergonomic-based risk to the employee during the widget production line workstation job demands. Based on the revised NIOSH lifting equation and the REBA worksheet results I can conclude that an employee performing tasks on the widget production line is exposed to higher than acceptable levels of ergonomic-based risks that may lead to injuries or illnesses. The risk perception survey presents data to show that the respondents feel the workstation fits them, when the revised NIOSH lifting equation and REBA worksheet provide quantitative and semi-quantitative data that shows otherwise. Based off of this data, I can conclude that the

59 59 ergonomic-based employee risk perception is low compared to the actual ergonomic-based risks present. In conclusion, this study determined that the widget production line s ergonomic-based risk factors are potentially likely to affect employee health and well-being. Recommendations Recommendations related to this study. It has been concluded that employees are exposed to high levels of ergonomic-based risk. These high levels of ergonomic-based risk may contribute to employee injuries or illnesses. To improve the widget production line at company XYZ, the following recommendations are being offered. Recommendation #1. Company XYZ should consider implementing change to lower the risk levels experienced by the employees on the widget production line. Therefore, it is recommended that company XYZ consider an engineering control of designing test gauge capable hooks which allow the test gauge to be lowered by the crane hoist above. This in turn may reduce or eliminate ergonomic-based risk factors on the widget production line. Recommendation #2. After implementation of the said engineering control on the widget production line, it is recommended that an ergonomic-based analysis is performed. This is recommended to ensure that the ergonomic-based risks have been eliminated or reduced to appropriate levels on the widget production line. This will specify if the widget production line of company XYZ continues to expose its employees to high levels of ergonomic-based risk factors, indicating if further change is or is not necessary. Recommendation #3. While performing the ergonomic-based analysis, it is also recommended that the individual involve the engineering, production, and quality departments as well as widget production line employees to perform a hazard analysis. This will provide a team of company XYZ experts to perform a hazard analysis. The team may analyze multiple factors

60 60 of the widget production line at the same time. This team based hazard analysis would allow company XYZ to utilize its resources efficiently and effectively to determine if the widget production line is contributing equally to quality, productivity and safety goals. Recommendation #4. Fourthly, it is recommended that company XYZ implement ergonomic-based Manual Material Handling (MMH) training to the employees on the widget production line. The widget production line workstation requires MMH while employees are performing tasks that present ergonomic-based risks. Employee MMH training may provide company XYZ with competent individuals that will possibly identify increased ergonomic-based risks during the job task. Following MMH training requirements, once an employee identifies increased ergonomic-based risks the individual will alert management. This may in turn reduce or eliminate the opportunity for employee ergonomic-based injury or illness on the widget production line by improving the risk perceptions of the employees. Recommendation #5. Furthermore, it is recommended that company XYZ survey its employees to determine if the individuals have any ideas on how to improve the widget production line by reducing ergonomic-based risks. The widget production line employees are experts on the widget production line. Therefore, this survey would possibly benefit company XYZ by capturing all employee ideas on how to improve the widget production line. This survey may provide the foundation for eliminating ergonomic-based risks and future employee injuries and illnesses. Recommendation #6. Lastly, an additional recommendation for company XYZ is to implement a physical capability screening program for new hires and employees performing work on the widget production line. Therefore, company XYZ would have the capability to determine if the current employee or prospective employee s physical work capabilities meet or

61 61 fail to meet the widget production line job requirements. This would allow company XYZ to hire individuals that meet the physical requirements of the widget production line. Additionally, it would allow company XYZ to structure it s manpower in a system that reduces the possibility of ergonomic-based employee injuries and illness on the widget production line. Recommendations for further study. An area that is now recommended to have been investigated further was the risk perception survey. Additional questions may have revealed detailed information that would have provided useful information to this study.

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65 65 Appendix A: Revised NIOSH lifting equation asymmetry graphic 8

66 66 Appendix B: REBA worksheet REBA Employee Assessment Worksheet A. Neck, Trunk and leg Analysis Step h : A\ijUSll.. ~ lfn.eck is m-isted: +1 If neck ls side bending: +1.. ~~ Trunk Posture Sce>te l egs I g' -Step:: L~ate IruukPo<>iriou Table l'!"ff"r:r.r ll B (!/~.Q- +~\ w :~ ~ ~ Step 2s: Adjust.. If mwk is misr.ed: +1 lf mwk is side belldinr: +1 s~"p L : l j, \ ;( +3 ~:, l, I I TNI.k Score ( :\dju'st: ~ ~ Leg Scote ~ : +2 / Add+l / Add+2 Step 4: Look-up Po:aure Scon iu Table.-\ UsiDg nhle; from steps l-3 :;.bon,. loca:e score in Table A Step!-: Add ForceJLo:td Score lfload < lllbs: +O tfloadll to221~ : + 1 lf load > 22 lbs: +2 Adjus1: lfsbock:ornpl.d buildupofforce: 3dd+i -,tep 6: ~ o re.-\.! find Ron- in Table C Add \'alues fro:u s;e~ ~ & 5 to obtain Score A. Find Row in Table C. Scoring ~ 1 = negligible risk 2 or 3 =- low risk, ch.mge may be needed to 7 = medium risk, further investig.cition, change soon 8 to 10 = h.igh risk, investigate ond implement change 11-t = very high.-isk, implement ch~nge SCORES g g 8 g g lowe< Arm r ~ ~,~ Uppe Arm Score g g g 6 6 g t1 11 II II g Q ' to lo 11 II 11 1\ t2 t2 12 1l 11 l t t l t t2 t2 12 ~:--::-::----,-JI Table c Score". / I +._I =-::----' Rna! REBA Score Taskoame: Reviewer:~ Activily Score I B. Arm and Wrist Analysi,s Step i: Locate t"ppn Arm Positiou: +2~ ~ ff,.\.: xo. ~.,.&5-90" 2J" :o in ;:.~,;~r~.... ~ f: f Step?.:t: Adjust... If sboolder is r.ri~d:: + 1 If upper ann is abduc(ed: I If ann is- suppor.ed o: persoo is lewd;: 1 ~tep 9: Locar~ Wri-st Position,;.. \ ~ + 1 ~~~ +2,~- ~-r Step 9-3,: Adj~.. If wrist u be:.ut from midlin.e or nr.im~d : Add +i Step 10: Look-up Posture St'ore in Table B Using", nl~ from mps 7-9 abo\ e, locale s.c.ore in Table B Step 11: :\dd Coupliog ~<ore Well nmog Haudle :md mid rang power g;rip,1ood: +0 Acceptable but not id-eal band bold ot coupling s.ccept:lble \\ith anomer body pm; foir: +J H:;.od hold oot occep~able bui pos.;ible} JKI<'r: +l No bandles. awkwnrd. tl!uaie with my body pa.:t. t.tttoc uptable: +1 ~t~p 1!: ~on B: Find Column in Table C Add nlues from s~eps.10&11 to obt~uo Sco;~ B. Fbd colw:m in Tabl~ C and nl31ch witb. Score A io row from m -p 6 to ob:ain Table C Score. Lower Arm... + Step 13: :\tth i ~ ~C'ON +1 1 or more body pam Me held for lo:1ger than 1 wiuute (st:uic) +1 Repe~ted ;mill rage actions (more thad 4xper minu,e) +1 Action caus:es rapid large range changes id posnues or unstable base Date:! / prol';ded hy PriKticiJ Ergonomics!l>.rlo>~.ccm (816}

67 67 Appendix C: Risk perception survey Have you ever been injured working on the widget production line? Yes No If yes, what type of injury or illness did you suffer? Was this injury or illness consistent with previous injuries or illnesses you may have suffered before employment at this organization? Yes No Have any injuries or illnesses been reported on the widget production line while performing lifting or lowering tasks? Yes No Have you ever spoken to management about issues with lifting or lowering test gauges on the widget production line? Yes No Has a Job Safety Assessment been performed on the widget production line? Yes No If yes, were you involved in the Job Safety Assessment? Yes No Do you feel that the job tasks required on the widget production line could be improved? Yes No

68 68 If yes, do you have any recommendations for improvement? Yes No If yes, please explain: Do you feel working on the widget production line is safe? Yes No Do you feel the widget production line workstation could be improved? Yes No If yes, why do you feel the widget production line workstation could be improved? Do you feel the widget production line workstation fits you? Yes No If no, why do you feel the widget production line workstation does not fit you? Have you ever experienced a lower back injury on the widget production line? Yes No

69 69 Appendix D: Revised NIOSH lifting equation evaluation Revised NIOSH lifting equation evaluation Frequency Lifts/min (F) Object weight (lbs) 31 Origin Recommended Weight Limit Destination Recommended Weight Limit Origin Lifting Index Destination Lifting Index Work Duration Hand Location Vertical Origin Destination Distance H V H V LC X HM X RWL= R\VL = LI= (31 / ) LI= (31 / ) Asynunetric Angle Frequency Rate Duration Object Origin Destination lifts/min Hrs Coupling A A c VM X DM X Al'vl X FM X CM

70 Appendix E: REBA evaluation 70

71 Appendix F: Cost effectiveness comparison evaluation 71 Cost effectiveness comparison of a control that prevents overexertion i'!iuries pertaining to the lower back Average payment for one lower back Year injury or illness 1st nd rd 8467 # oflower back injuries or illnesses Average inflation reduced or cost savings in factor ( 1 +inflation eliminated annually current USD rate t ' (Ll)" O= LOO (U)"l= UO (U)"2= = control life expectancy 1 0% = Average inflation factor 11% = ROI factor Return on investment factor (ROI): (1+ rate of Current value of Future cost savings ROI)n-1 future savings (U 1)" 0= LOO (Ul)"l= Ul (U 1 )'"' 2= =Total current value of injury costs (USD) =Cost of control (USD) =Current value of savings (USD)