The real value in the workplace ergonomics process is making improvements to the workplace that quantifiably reduces risk. Knowing the ergonomic risk factors present in your workplace is great, but making improvements is the name of the game.
That’s why the next step in the ergonomics process is so important. At this point, you have:
- Conducted ergonomic assessments to determine risk is above an acceptable limit.
- Prioritized this job task for improvement, and
- Conducted what-if analysis so you understand how workplace changes would impact ergonomic risk factors
The next step is brainstorming with the ergonomics team to uncover all of the possible improvement scenarios for a job task. This involves four steps:
- Understand the root causes of ergonomic risk factors
- Review ergonomic assessment guidelines
- Review ergonomic considerations from head to toe
- Document improvement scenarios
Understand the root causes of ergonomic risk
The first step to improving anything is to understand the root causes of the problem in the first place. Look at the ergonomic assessment you conducted for the job task and look for the task variables that caused the highest increase in the Risk Index. This will help you understand the biggest problems with the job task which are also the biggest opportunities for improvement. At this point, it’s also helpful to play around with the what-if analysis tool to help you understand how changing these variables impacts the Risk Index.
Review ergonomic design guidelines
Use of ergonomic design checklists (along with an understanding of the principles of ergonomics and the considerations listed below) will give you guidance on ergonomic workstation design to maximize productivity and minimize employee fatigue and discomfort that could eventually lead to an MSD.
Review ergonomic considerations from head to toe
Head / Neck
The nerves of the body enter the head through the neck. With such sensitive wiring passing through such a mobile structure, potential for problems is high.
Potential MSDs
- thoracic outlet syndrome
- tension neck syndrome
- cervical disc disease
Ergonomic Design Principles
- A. Allow for tallest workers
- B. Avoid forced forward head posture
- C. Natural posture is to look down slightly
- D. Avoid narrow viewing angles and visual obstructions
Shoulders
Shoulder MSDs are associated with postures that place heavy loads on its muscles and tendons. Since the arm provides a very long lever, holding even small loads in the hand with the arm held away from the body will quickly result in shoulder fatigue and discomfort, and place substantial stress on the tendons in the shoulder.
Potential MSDs
- rotator cuff tendonitis
- bicepital tenosynovitis
- frozen shoulder syndrome
Ergonomic Design Principles
- A. Place items and parts between shoulders and waist height
- B. Avoid reaches above shoulder and reduce any excessive reaching
- C. Avoid greater than 45o shoulder flexion and abduction
Elbows
The elbow is actually two different joints. It raises and lowers the arm (flexion and extension) and also acts as the pivot point for forearm rotation (pronation and supination). There are numerous vulnerable soft tissues (tendons, nerves, blood vessels) that pass though the elbow to reach the forearm and hand.
Potential MSDs
- lateral and medial epicondylitis
- radial tunnel syndrome
- cubital tunnel syndrome
Ergonomic Design Principles
- A. Normal work (medium weights) work surface designed to just below elbow height
- B. Precision work (light weights) raise surface above elbow height and provide upper extremity weight bearing support when possible
- C. Heavy work place work surface 6-8” below elbow height
Wrist / Hand
The wrist is an incredibly mobile joint that contains numerous tendons, nerves, and blood vessels, which service the hand and are vulnerable to MSD.
Potential MSDs
- tendonitis
- carpal tunnel syndrome
- ganglion cysts
- trigger finger
- DeQuervain’s
Ergonomic Design Principles
- A. Maintain neutral posture
- B. Avoid repeated or sustained flexion and ulnar deviation
- C. Avoid repeated or sustained pinching and allow for small hands when designing gripping tasks and selecting hand tools
- D. Allow plenty of access space for large hands
Lower Back
The back is a flexible curved column composed of a series of bones (vertebrae) separated by shock absorbing discs. The structure is held together by a large number of muscles and ligaments. Acting together, they give the spine the ability to bend and twist. The spine protects the spinal cord and acts as a distribution center for the nerves.
Potential MSDs
- degenerative disc disease
- fatigue strains (muscle or tendon) and sprains (ligaments)
Ergonomic Design Principles
- A. Avoid repeated lifting that requires excessive forward bending
- B. Avoid sustained forward bending
Legs
Very little research exists on the relationship between work activities and lower extremity MSDs. However, there are some MSDs associated with the legs, and ergonomic design principles that we should keep in mind.
Potential MSDs
- plantar fasciitis
- tarsal tunnel syndrome
- Tailor’s Bunion
Ergonomic Design Principles
- A. Avoid foot actuation if possible
- B. Avoid repeated walking up and down steps
- C. Avoid mechanical stress on the legs
- D. Allow for long legs
- E. Provide adjustments or footrests for shorter legs for prolonged sitting
Document improvement scenarios
After reviewing the ergonomic analysis and reviewing design best practices, you should have a few ideas for ergonomic control methods you could implement for the job task.
Improvement scenarios should be documented into whatever system you’re using to manage ergonomics. See the video below for an example of how to document improvement scenarios using the ErgoPlus Platform:
