Course Learning Outcomes for Unit VII

 Upon completion of this unit, students should be able to:

5.     Assess common workplace stressors.

5.1        Identify workplace factors that lead to the development of musculoskeletal disorders (MSDs).

 6.     Apply contemporary methods of conducting workplace evaluation to ergonomic-related hazards.

6.1        Apply evaluation methods and assessment tools.

 7.     Evaluate common controls for mitigating ergonomic-related hazards.

7.1        Recommend controls for mitigating ergonomic hazards.

 Required Unit Resources

 Chapter 1: Human Factors and Ergonomics from the Earliest Times to the Present, pp. 14–23

 Chapter 4: Standing and Sitting at Work, pp. 135–147

Chapter 5: Repetitive Tasks: Risk Assessment and Task Design, pp. 183–188

Chapter 6: Design of Manual Handling and Load Carriage Tasks, pp. 224–234

 Unit Lesson
The Office

Betty White is one of several employees who work at a 24-hour call center in Spokane, Washington. As a customer center representative, Betty is required to work a 12-hour shift, five days a week. Her office setting is a cubicle that includes a computer, telephone, printer, file cabinet, desk, and chair. Betty shares her desk with Leslie Jones, who works the shift opposite of hers. While Betty is five feet and two inches tall, Leslie is closer to six feet tall. After performing her responsibilities at her cubicle for several years, Betty has been suffering recently from low back, hand, and neck pain. As a result, Betty communicated her pain to her supervisor and has requested to have her workstation evaluated. Her supervisor informs Betty that the call center is being relocated to a new office building that was recently constructed and assures her that her problems will improve once they move into the new building as they will be getting new office furniture. Six weeks after settling

into the new building, not only is Betty continuing to experience problems with her back, hands, and neck, and she is now complaining of headaches and nausea. The supervisor is baffled by Betty’s response to her new work environment and has reached out to the company safety manager to discuss the problem. 

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Like Betty and Leslie, millions of people sit in front of a UNIT x STUDY GUIDE computer all day to perform their work responsibilities. ITitle       n many instances, after spending most of their workday  sitting in front of a computer, these same people go home and spend more time sitting at their home computer or doing other repetitive hand intensive activities for relaxation (e.g., playing video games, texting), or perhaps like you, they are enrolled in distance learning courses that require them to spend many hours on the computer completing homework assignments. Oftentimes, frequent computer users suffer from a variety of muscle strain and stress-related injuries because their workstations are not properly set up. Think about how often you slouch in your chair or strain to reach items on your desk as a result of your

workstation setup. This type of awkward working posture

leads to neck, shoulder and back pain, and other issues

and impedes concentration and productivity. To remedy

these types of issues, many companies are investing in ergonomic assessments and are realizing the benefits it offers their employees and their business.

Musculoskeletal Disorder (MSD) Risk Assessment and the Ergonomic Improvement Process

Effective and efficient risk assessments are the essence of a successful ergonomics improvement process. Applying a scientific, evidence-based approach allows for the identification and quantification of ergonomic risk factors as well as the implementation of improvements to eliminate and/or minimize ergonomic risk factors. To get a clear view of the risk that is present in the workplace, jobs must be effectively assessed for specific physical workplace factors, including force, posture, compression, repetition, duration, vibration, and temperature. Once a potential musculoskeletal disorder (MSD) risk has been identified, the focus of the assessment is determining the level of injury risk that exists. Although conducting an ergonomic assessment can help to identify trends using workplace injury data, an assessment performed in response to an injury is a reactive approach to controlling and preventing MSD injuries. Conducting a risk assessment before an injury occurs is a proactive approach that is not only necessary to get out in front of a problem but is also more cost effective than implementing a process in response to a workplace injury and/or illness.

Understanding the Benefits of an Ergonomic Assessment

Conducting an ergonomic risk assessment is beneficial to both employers and employees as it is a means of ensuring job duties are completed successfully and assigned tasks are within workers’ capabilities and limitations. Employees experiencing the pain and discomfort of a work-related injury will likely perform their job tasks with more difficulty and less efficiency. Providing appropriately designed work tools and work environments allows employees to feel less taxed when performing work tasks, which can contribute to greater focus, improved efficiency, and better quality of work. In addition, conducting assessments regularly can help to foster a positive safety culture that is crucial for maintaining employee satisfaction and retention. Employers who take the time to conduct MSD risk assessments, evaluate the findings and make corrections based on the risk identified during the assessments, can not only expect to see a reduction in costs associated with workplace injuries, but also improvements in the overall productivity of the workplace operations. 

Conducting an Ergonomic Risk Assessment 

The best approach for conducting an ergonomic risk assessment is to make it an ongoing process of risk identification and risk mitigation that focuses on a different set of MSD risk factors. This will allow you to identify common issues, injuries, and complaints; zero in on high-risk departments or job types, and establish data-driven benchmarks that will be important for measuring success in the future. The following five steps can be used to conduct an effective ergonomic risk assessment.

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Title

Ergonomics Evaluation Methods

There are many tools available for the analysis of physical workplace risk factors, but they can be generalized into four categories (Stack, Ostrom, & Wilhelmsen, 2016).

•        Checklist o Pros: Ease of use, No special equipment requirements, reminders o Cons: Easily misused, observer bias, not flexible

•        Interactive form based (Questionnaires) o             Pros: Can be validated, potential respondent anonymity, sample large population quickly o       Cons: Responder bias, costly to validate

•        Observational o Pros: Ease of use, Flexible, Can be validated

o   Cons: Observer bias, observer presence can alter environment

•        Direct Measurement o   Pros: Can be validated, reliable

o   Cons: Equipment can be costly, test environment may represent true working conditions, and equipment presence can alter work methods

Ergonomic Assessment Tools

No single assessment tool is perfect for every situation. The key to selecting the most appropriate assessment tool is matching the tool with the type of job task being evaluated. Choosing the wrong ergonomic risk assessment tool is similar to trying to screw a bolt into the wall using a hammer—it simply does not work. Not only is it frustrating and time-consuming but the quality of the craftsmanship suffers as well. That is why selecting the right tool and using it the right way is so important. 

The following is a summary of frequently used ergonomic assessment tools listed by the corresponding type UNIT x STUDY GUIDE of job task. The tools were developed based on objective research by organizations such as the National Title Institute of Occupational Safety and Health (NIOSH) and the Washington State Department of Labor and  Industries, among others (Middlesworth, 2015).

•        Lifting/Lowering Tasks  o Washington Industrial Safety and Health Act (WISHA) Lifting Calculator 

▪  Can be used to perform ergonomic risk assessments on manual lifting and lowering tasks or as a screening tool to identify lifting tasks, which should be further analyzed using the NIOSH

Lifting Equation o           NIOSH Lifting Equation

▪  Can be used to assess the manual material handling risks associated with lifting and lowering tasks using job task variables to determine safe lifting practices and guidelines

•        Upper Body Posture  o             Rapid Upper Limb Assessment (RULA) 

▪   Diagnostic tool that can be used to assess the biomechanical and postural load requirements of job tasks/demands on the neck, trunk, and upper extremities

•        Entire Body Posture  o             Rapid Entire Body Assessment (REBA)

▪   Diagnostic tool which uses a systematic process to evaluate whole body postural MSD and ergonomic design risks associated with job tasks

o   Body Map Questionnaire 

▪  Can be used to gather evidence about the effects of work on the human body and identify clusters of problems that may need to be further investigated

o   WISHA Caution Zone Checklist and WISHA Hazard Zone Checklist

▪  Diagnostic tool that can be used to evaluate ergonomic risks factors, including awkward postures, highly repetitive motions, high hand force, repeated impacts, lifting, and hand-arm vibration

▪  Can also be used as screening tool to identify tasks, which should be further analyzed using the Hazard Zone Checklist

•        Pushing/Pulling: Snook Tables o           Liberty Mutual Manual Material Handling Tables (Snook Tables)

                      ▪        Can be used to outline design goals for lifting, lowering, pushing, pulling, and carrying tasks

•        Hand-Arm Vibration  o             Hand-Arm Vibration Calculator

▪   Can be used as a guide to evaluate hand-arm vibration exposure and provide suggestions with respect to reducing associated risks

Conclusion

MSDs are becoming increasingly more common in today’s workplace. Work requirements often result in exposure to ergonomic risk factors and increase the probability that workers may develop an MSD injury. There are a variety of specialized checklists and other tools available for the assessment of ergonomic risk factors in the work environment. Some are based on visual observation of tasks, while others require measurement using various ergonomic tools and equipment. Regardless of the method selected, identifying, quantifying, and implementing controls to systematically minimize ergonomic risk factors is essential in order to prevent costly MSD injuries.

References

Chernetskaya. (2016a). Posture concept. Young woman suffering (ID 105542468 [Photograph]. Dreamstime.

https://www.dreamstime.com/posture-concept-young-woman-suffering-posture-concept-youngwoman-suffering-neck-pain-working-computer-office-image105542468

Chernetskaya. (2016b). Posture concept. Man suffering from back pain while working with laptop (ID 105542087 [Photograph]. Dreamstime. https://www.dreamstime.com/posture-concept-man-sufferingback-pain-working-laptop-posture-concept-man-suffering-back-pain-working-image105542087

Middlesworth, M. (2015, April 10). Five steps to conducting an effective ergonomic risk assessment UNIT x STUDY GUIDEOH&S.                                                                                

https://ohsonline.com/Blogs/The-OHS-Wire/2015/04/Conducting-ErgonomicTitle -Assessment.aspx

Stack, T., Ostrom, L. T., & Wilhelmsen, C. A. (2016). Occupational ergonomics: A practical approach. Wiley.

Suggested Unit Resources

Although not required, reading the below sections of your course textbook will aid in your understanding of ergonomic design and assessment: 

Chapter 7: Work Capacity, Stress, Fatigue, and Recovery, pp. 262–276

Chapter 8: Job Demands, Health, and Well-Being for a Changing Population, pp. 303–310

Chapter 9: Working in Hot and Cold Climates, pp. 337–339

Chapter 10: The Visual Environment: Measurement and Design, pp. 371–381

Chapter 11: Hearing, Sound, Noise, and Vibration, pp. 408–422

In order to access the following resource, click on the link below.

The Department of Defense (DoD) Environment, Safety and Occupational Health Network and Information Exchange (DENIX), Ergonomics Working Group provides links to ergonomic assessment tools and prevention strategies.

Ergonomics Working Group. (n.d.). Assessment tools. Denix. https://www.denix.osd.mil/ergowg/assessmenttools/

Learning Activities (Nongraded)

Nongraded Learning Activities are provided to aid students in their course of study. You do not have to submit them. If you have questions, contact your instructor for further guidance and information.

Exercise #9 on page 153 in the course textbook is recommended to provide you an opportunity to become more familiar with using the rapid entire body assessment (REBA) of ergonomics tool to evaluate job tasks.