Ergonomics, the science of designing workplaces and work stations to meet the physical needs of workers, is often dismissed as too expensive or requiring too great a degree of modification of the existing assembly line design to be cost-effective to employers. Redesign of the workspace alone is not sufficient to prevent the majority of repetition-related injuries. Other factors include a fast work pace, employees’ lack of control over aspects of their job, workload, peer support and the overall environment of the larger factory or work area.
Production Line Automation & Ergonomics
The increasing use of automated production lines with robotic task performance has failed to eliminate the need for human labor in most processes. It has become even more crucial to fill those positions still requiring human judgment and skill with experienced, well-trained and efficient employees. These employees are not instantly replaceable and thus the protection of their health and means to ensure their safety are necessary to maintain production and profit.
Bosch Rexroth, a major industrial manufacturer in Europe, accepted the challenge to redesign its production lines knowing that almost half of employees in the field complained of significant pain or fatigue from poorly designed workstations. An expert in manual production systems at the company, Ross Townshend, outlined seven necessary factors to take into account for a redesign:
- Body & Working Height
- Work area heights should be between 800 millimeters (2 feet, 7.5 inches) and 1500 millimeters (approximately 4 feet, 11 inches).
- Work performed outside of this recommended range can lead to poor postural adjustments, cervical strain and eyestrain.
- Optimally, employees should have the ability to alternately sit or stand and continue to perform the tasks of their job.
- Work Area
- Work area rules to minimize injury and maximize comfortable job performance include:
- Avoid work surfaces taller than 4 feet, 11 inches—the measurement considered to be “working above the heart;”
- Actively promote movement to prevent impaired circulation to the lower extremities;
- Use a stand-up/sit-down work station or job rotation among employees to allow for varying degrees of physical exertion;
- Use mechanical rollers or lifters to avoid back exertion and strain.
- Work area rules to minimize injury and maximize comfortable job performance include:
- Reach zone
- Reach zone rules in workstation design included:
- All work materials—including containers, operating elements and equipment—should be within easy access, taking into account the different sizes and reach distances for employees. This first rule decreases the chance of sprain or dropping the container, item or fitting sought. In the case of liquid materials, spill control supplies should also be in the same area.
- Rotating at the waist—or torso rotation—should be avoided to eliminate potential strain to the oblique muscles.
- Work stations require three zones in their design—at hand, close and a little farther than that—depending upon the frequency of use of the item sought.
- Reach zone rules in workstation design included:
- Parts Presentation
- The redesign for parts presentation includes the following now-familiar interventions:
- Frequently-used items should be at hand or nearby;
- Parts considered heavy for the job should be stored in easily accessible lower containers;
- Use mechanical rollers or lifters to avoid back exertion and strain.
- The redesign for parts presentation includes the following now-familiar interventions:
- Range of Vision
- Crucial aspects to this aspect of work station design include:
- Eliminate unnecessary head, eye and neck movements;
- Minimize or eliminate the need for refocusing by maintaining items in the same vision distance;
- Workers should never manipulate tools or fasten materials outside of their range of vision.
- Crucial aspects to this aspect of work station design include:
- Lighting
- Ergonomic lighting adjustments and corrections include:
- Avoiding very dark and very bright illumination extremes;
- Eliminate glare or reflective shine back into the employee’s face;
- Eliminate glare, unlit areas or flickering lights from all workstations.
- Ergonomic lighting adjustments and corrections include:
- Adjustment of Work Equipment
- Easy adjustment and manipulation of all work equipment—chair height, table height, bin distance, lumbar support—must be designed into the system so that each workstation can be personalized to meet the needs of the specific worker for that shift.
Consider Ergonomics Now to Benefit the Future
To avoid employee injuries and to keep production consistent, it’s crucial for factories and other similar work environments to consider ergonomics when designing their work stations and spaces. Consider using online evaluation tools to help guide these designs, or perhaps even reach out to an expert in the field of ergonomics. Taking such precautions now will positively impact your company’s bottom line in the long run.
Originally posted on June 3, 2013 @ 6:35 pm