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Case Studies

Return to Work - Matching Worker Restrictions with Job Demands

1. Background

Ergonomics is not only used to prevent injuries from occurring on a job, but is also used to aid in the placement of workers who have been injured. It can be used to help accommodate the workers restrictions. In this case study, a worker was injured while at work and had been off work for some time. The employer wished to bring the worker back to work but was not sure what the worker was able to do. This case study details the steps taken to bring the worker back to a safe, meaningful position in the company. The company in this case study was a heavy automotive assembly plant.

2. Ergonomic Improvement Opportunity/Identification or Outline of Problem

The company had a general problem with its return to work program. The company in the past had not brought many workers back to work unless they were capable of completing their full duties or they placed them in very modified areas (i.e. stores) where they then had problems removing them. The company wanted to start finding productive work for those returning with restrictions and wanted to look into an early return to work program to keep their WSIB costs low.

3. Analysis

The analysis began with a review of the possible jobs that the employer outlined the worker could return to. This was based on the worker's classification and seniority. A detailed physical demands analysis and risk assessment was then completed on each job. The physical demands of each job were then compared to the workers restrictions as stated in the WSIB Functional Abilities Form filled out by the workers physician.

4. Identify Solutions

Based on the comparison, recommendations were made as to the most suitable job available, as well as, for changes required to the jobs to make them suitable.

5. Test Solutions

The company made the final decision as to which jobs the worker would return to and implemented all changes required to ensure the job accommodated all of the workers restrictions. A meeting was arranged with the worker to outline the job they would be returning to and to note any concerns the worker had before returning to the job. Concerns were discussed and a formal job plan was written and signed by all parties.

6. Implement

The worker returned to the job and after a brief period reported problems. At this point, the Ergonomist met with the worker again, to discuss his issues and come up with any additional recommendations needed for a safe and successful return to work. The Ergonomist, worker, and employer worked together to ensure all restrictions were accommodated. This situation required educating the worker on body mechanics and alternative work methods, ensuring tools were in place where needed, and making an additional change to the workstation due a part change that had occurred since the original assessment.

7. Evaluate

With the changes implemented, the worker felt that his needs had been addressed. The employer and the worker were confident in his placement on the job and comfortable that he would not aggravate or re-injure his condition. Success in this type of return to work program relies as much on an open and honest relationship between the worker and employer as it does on the hard data collected during the comparison. The ergonomist is able to provide a third party objective view of the situation, explaining to both parties the need for changes and training. This objective viewpoint often encourages open discussion and addresses concerns early in the process. This often ensures that the worker will remain at work and if applicable may work back in their original position within the company. With an early successful return to work plan, a company can save thousands of dollars on each case (see Ergonomics: Cost Savings extends further than injury cost reductions, Newsletter Archives 2002).

Although this example was a WSIB case, the process can be used for any worker returning to work with restrictions. If you are interested in discussing return to work and job matching options please contact us.

Options Inc. has also designed a "Job Matching Tool" that helps take the hard work out of determining suitability of a job for a worker with restrictions. If you are interested in viewing this tool, or learning more about it, please contact us.


Office Ergo Online - User Trial and Validation Case Study

1. Background

Options Inc. developed an online Office Ergonomics Training Program, "Office Ergo On-line", to provide clients a cost effective and time efficient means of training their employees on office ergonomics. The program allows workers to make ergonomic changes to their workstations independently and to contact someone within the company for additional help when needed.

A large insurance carrier was interested in providing their employees with access to the "Office Ergo On-Line" Version 1.2 program on a Nation wide basis. This version of the program includes instructions on workstation setup, a comfort survey and progress questionnaire that allows reporting and tracking. However, before this program was launched Nation wide, a pilot study was conducted within one of their large office locations.

2. Ergonomic Improvement Opportunity/Identification or Outline of Problem

This study was conducted to determine if the "Office Ergo On-line" program is useful and can help a company implement an ergonomics program on a Nation wide basis with little impact to their overall current system. The information collected from the study will be used to make changes to the program to increase its usability, to improve the outcomes, and to provide information to the company to aid in implementation of the program. The main purposes of the study were:

  • to determine if implementation of the "Office Ergo On-line" program can effectively assist employees in identifying concerns with their workstation;
  • to determine if implementation of the "Office Ergo On-line" program provides workers with the required information to make appropriate changes to their workstation; &
  • to determine the ease of use of the "Office Ergo On-line" tool.

3. Analysis

All participants (17) attended a start up information session. During this session, the format and purpose of the study was outlined, as well as, their duties as a participant within the study. Following the information session, an Options Inc. Canadian Certified Professional Ergonomist visited each participant, at his or her workstation. This Ergonomist completed the assessment form through observation and minimal discussion with the employee, to ensure an unbiased assessment. In order to obtain a quantitative value for each assessment, the assessment form was created using a Yes/No format with all "Yes" answers scored as a 1 and all "No" answers as a 0.

Participants were then emailed instructions on how to access the "Office Ergo On-line" program. The participants were given three weeks to complete the program and were instructed to complete the user questionnaire after they finished using the "Office Ergo On-line" program.

Three weeks later, the same Options Inc. Ergonomist returned and completed a post assessment of each workstation. This assessment was completed using the same assessment form and protocol. Only 12 of the 17 participants were reassessed as the remaining 5 participants either did not complete the program or had changed desks and locations so the information collected in the program and the "Pre" assessment was no longer valid.

Once the assessment was completed, the results and concerns were reviewed with each participant. The ergonomist noted any changes made by the participant since the last visit and made further recommendations where required. The user questionnaire was also collected at that time.

4. Validation Measures

The measures for this validation exercise included:

  • a comparison of the scores on the "Pre" and "Post" Assessment forms completed by an Options Inc. Canadian Certified Professional Ergonomist;
  • a comparison of the Ergonomist's assessment to the participants responses to the feedback questions within the "Office Ergo On-line" program;
  • a comparison of the Ergonomist's assessment to the responses to the Comfort Survey completed within the "Office Ergo On-line" Program; &
  • Rating of the programs usability based on the results of the User Questionnaire.

5. Results

The average assessment form score improved to 15.75 from the initial average score of 14.50. A perfect assessment score, using this form, is 21. Comparison of each participant's scores before and after using the program showed that 8 of 12 participants improved, 3 of 12 had no change, one of 12 demonstrated a decreased score or an increase in problems observed by the Ergonomist.

Comparison of the concerns indicated by the Ergonomist to the requests for additional help made within the "Office Ergo On-Line program" showed that 11 of 14 participant requests for help matched. This means that 78% of the requests for additional help were required and that 22% of the requests were unnecessary, based on the Ergonomist's assessment.

Direct comparison of the Ergonomist's assessment to the observations made by the participants demonstrate that 58-84% of the participants were able to accurately assess their chair posture, back support, typing posture, monitor height and monitor distance. Participants had difficulty assessing reach zone issues, as only 41% were able to accurately assess this issue.

Of the participants who completed the Comfort Survey, 4 of 12 participants, all discomfort indicated by the employees was validated with the Ergonomist's assessment of their workstation.

The results of the user questionnaire (usability of the Office Ergo Online Program) showed that:

  • 100% of the participants understood the instructions and were able to navigate through the program without difficulties;
  • 100% of participants reported the program easy to use; &
  • 78% found the instructions on how to make the changes/ adjustments easy to implement with 23% having some difficulties.

6. Conclusion

Overall the program had a positive affect on the identification and control of ergonomic risk factors in an office setting.

From the results collected, the following conclusions were made:

  • the participants were able to identify concerns with their workstations;
  • the participants were able to make some limited changes on their own and these changes resulted in improvements to their workstations; &
  • the program was easy to use.

7. Recommendations

  • Procedures outlining how the company will handle the results and feedback from the program need to be created.
  • The three questions in the Ergonomist's assessment form that resulted in a worse score were due to participants changing chairs. The chairs that they changed to were not suitable and created further problems. As a result, a chair standard and detailed chair information (developed by Options Inc.) should be utilized to ensure the new chairs are more suitable for the User than the current chairs. Utilizing these documents will help minimize changes that are detrimental.
  • A minor grammar error was identified in the program. This was corrected immediately.
  • It is recommended that a prompt be added to the program that reminds the user to complete the comfort survey. 8 of the 12 participants that completed the program did not complete the Comfort Survey, stating that they did not remember this aspect of the program. This prompt could be added to the first and/or last page of the workstation set-up section and would remind the user to complete the comfort survey before leaving the program.


Recent Health Concerns Underscore the Need for Usability Testing

A health and safety concern and HIV warning has been recently issued by Sunnybrook hospital, stating that equipment used to collect biopsies and test for prostate cancer had not received proper sterilization. This has placed 860 men who had these tests conducted between December 1999 and August 2003 at risk of contracting Hepatitis B and HIV.

Hospital officials blamed the complex manufacturer's instructions for the tool used to take prostate gland tissue as the main cause in this issue. In a recent media conference, Dr. Andrew Simor, head of microbiology at the hospital stated, "The people using the equipment did not understand [the instructions] and even I, looking at it now, can see why it would be easy to misinterpret." This is a tremendous and unfortunate example of the need for usability testing in equipment and instruction writing.

Usability testing involves collecting data while observing representative end users using the product to perform representative tasks. It measures the degree to which a product meets specific usability criteria, exposes usability deficiencies and gradually shapes or molds the product (Rubin, 1994).

Usability testing determines if a product can be used as intended, if instructions are easily understood and carried out and outlines problems to be corrected before the product becomes available to the public. Although this step may seem like common sense, many companies avoid such testing in favour of expert evaluations that do not involve representative end users.

The advantages for including usability testing in your design stage, a part from the obvious and most important issue of minimizing the risk of safety and health concerns are:

  • minimized cost of service and hotline calls;
  • increased sales and probability of repeat sales; &
  • acquiring a competitive edge since usability has become a market separator for products.

Regardless of whether or not this company conducted usability studies on their product, we can learn from this unfortunate result. Perhaps if more companies completed usability testing we would not encounter such unfortunate consequences.

If you are interested in receiving more information on Usability Testing please contact us.

References

Rubin, H. (1994). Handbook of Usability Testing, John Wiley and Sons, Inc., New York. http://www.canada.com/


Redesign of Automotive Manufacturing Assembly Conveyor

1. Background.

This project was completed at an automotive seat manufacturing company that was making large-scale changes to the assembly operation at the start of a new model year. An evaluation of the current conveyor system was completed to identify areas of concern. The basic premise for this was that a good match between design and the user should improve efficiency, safety, health and comfort, make things easier to use and improve the quality of the workers' lives. Solutions to eliminate these concerns were applied and implemented at the design stage. The new design was evaluated via drawings and simulation. Changes were then implemented and as a final check, an overview or summary assessment was completed.

2. Ergonomic improvement opportunity/Identification or outline of problem.

Previous involvement with this company, via station by station assessments, had identified several common issues due to the design of the assembly conveyor. Due to the type of work being completed, the height of the line was less than ideal at many stations. This resulted in the use of a large number of platforms along the conveyor line. The issue of platforms was not a problem, as they are often used as a reactive approach or control for ergonomic risk factors. However, as a proactive approach, the Engineering team was able to take advantage of retooling for a new model to investigate ergonomic design options and the removal of platforms. The goal was to ensure all working heights were suitable for a range of male and female workers (5th - 95th percentile). The ultimate goal was to minimize the occurrence of musculoskeletal injuries on the conveyor line.

3. Analysis

To begin the analysis a full assessment of each workstation on the assembly line was completed. This report identified the following:

  • station by station posture issues due to working heights;
  • force issues due to tools, materials and equipment; &
  • recommendations for reorganizing the location of workstations.

Recommendations and limitations were based on recognized guidelines and limits, which were identified in each report.

4. Identify Solutions

A solution, that was specific to the risk factors involved, was provided for each problem. Solutions ranged from simple height recommendations to repositioning or reordering of jobs in the assembly. Additional recommendations were made in terms of materials and tooling but these changes had minimal impact on the conveyor design.

A spreadsheet consisting of the Operation number, brief description of the tasks, ideal work surface height recommendation, estimated height of work from conveyor and a final recommended conveyor height was provided to the design team.

5. Test Solutions

The engineering group took the above recommendations and created CAD drawings of the proposed conveyor. These drawings were then used to re-evaluate the feasibility and effectiveness of each new conveyor height or job relocation. Ongoing communication and interaction with the Engineering team was required to ensure up to date information and conveyor design (height) restrictions were utilized. Due to task, tooling or equipment requirements, some changes could not be made. Alternate solutions were then sought. Finally, simulation of some tasks was completed (as the jobs did not exist in the old model) to further test prototypes, new tooling, and equipment and conveyor heights.

6. Implement

Once the recommendations were finalized, physical implementation of the changes took place. This occurred during a shut down period. During this period the consultant's role was minimal.

7. Evaluate

Once implementation had taken place, the consultant interacted with the workforce and engineering staff to ensure all changes made were correct. Additionally, the consultant addressed any discrepancies or problems the workforce had with the changes.

Although the goal was the elimination of all platforms - this was not possible as some stations simply could not be positioned to match the minimum and maximum vertical reach range for the tallest and smallest workers. For these exceptions, removable platforms were used to allow optimal height adjustment. There was however, a significant drop in the use of platforms with the redesign.

Of special note, this process began three months prior to the shutdown or installation period. Enough time was allotted for the complete assessment of the old conveyor and assessment of the design of the new conveyor to be completed. The entire process was completed approximately one month post installation, requiring a total of four months involvement. This is an ideal approach to the elimination of ergonomic risk factors via the redesign of the workstation.


Usability and Validation of a Computer Interface Display Suite

1. Background

As part of the human factors engineering support Options Inc. provided to a client, we reviewed a computer interface display suite from the human computer interface design perspective. The importance of a good computer interface design was important to this client from a safety, speed and accuracy perspective.

2. Ergonomic Improvement Opportunity/Identification or Outline of Problem

The computer interface display suite in question was being reviewed on a proactive basis. This display suite was already in use but due to a down period in the company, an opportunity arose to complete a proactive evaluation of the display suite.

3. Analysis

To begin the analysis, a full assessment of the display suite was completed using accepted industry specific computer interface design guidelines. This review identified 32 non-conformances. These non-conformances consisted of but were not limited to:

  • screen background colour;
  • no uniformity in navigational methods;
  • inconsistent button presentation;
  • improper use of colour; &
  • font sizes and colour improper.

4. Identify Solutions

A solution was provided for each problem. Solutions ranged from simple font size and colour changes, to major navigation method changes, and reorganization of page layouts. A table consisting of the General Overall Display Recommendations and Display (or page) Specific Recommendations was provided. In addition, entire mock-ups of each display page, with the recommended changes noted, were provided to the design team.

5. Test solutions

To test the changes and ensure no additional problems surfaced, a usability and validation test was conducted. This required a page-by-page mock up of the display to be created. PowerPoint was used to mock up the new display suite. Use of this program allowed the user to navigate through the mock display pages. This was completed via the presence of hyperlinks that allowed the users to navigate between the pages as they normally would within the display suite.

The end users, those that would be interacting with the program on a regular basis, participated in the testing. The participants were given an overview and brief verbal description of the changes made to the program. They were then asked to follow a series of instructions designed to test their ability to navigate through the program. During the testing they were encourage to verbally express their thought process when completing the tasks. The following measures were recorded:

  • the percent of displays the participants were able to locate successfully on their first attempt;
  • the percent of the values on the displays that the participants were able to locate on their first attempt; &
  • the participants rating on the program usability via questionnaire.

Comments and results collected showed a very favourable response to the changes, 100% of the displays and values were accessed and read by the users. Validation questionnaire responses were positive. User verbal feedback outlined additional areas for improvement.

6. Implement

Once all of the data was collected the additional changes were recommended. The recommended changes were forwarded to the design implementation team and final program changes were made. Due to the minor nature of the additional changes, further usability testing was not required. If the changes had included major alterations to the display suite, a full new usability test would be have been necessary.

7. Evaluate

Once implementation had taken place, the consultant was required to review the updated display suite and note any deviations from the previously noted recommendations. If any recommendation was not implemented, the reason for this was to be noted. All digressions required formal sign off and acceptance.

On evaluation of the final updated program, 28 of 32 changes had been implemented. The four not implemented were due to the confines of the software design. These have been noted and will remain issues to hopefully be resolved in future versions of the software.

This case study demonstrates the successful assessment and implementation of changes to a computer interface display suite using human usability research, and data collection methods

Copyright 2006 Options Inc. All rights reserved.