Many people get work-related back injuries, wrist disorders, and assorted strains and sprains. Injuries may occur suddenly or may develop slowly over time. Sometimes improving our “fit” while working can help prevent these injuries; however, often away-from-work factors complicate the ergonomics process.
Although it is believed that injuries are caused by many factors, I encourage you to be open to even newer ways of thinking about ergonomics, such as written work by Kate Montgomery and Anthony Carey. (1) Each brings a unique approach to ergonomics not applied among most safety and ergonomics practitioners today.
In straightforward ergonomics, fitting the task to the person means adjusting the way in which work is done; modifying equipment, job design, and layout; and adjusting for the physical capabilities of workers so that work does not cause musculoskeletal disorders. Some basic ergonomic adjustments include:
- Moving things in closer and within easy reach
- Raising or lowering chair or work surface
- Building in adjust-ability and redesign work areas for a comfortable work position
- Using the right tool for the task
- Being flexible and modifying your expectations according to your size and strength
- Providing adjustable equipment and workstations to accommodate differences in body size
- Using tools with a handle that fits comfortably in your hands —this allows work in a comfortable position (e.g., using vertical handles to accommodate different heights)
- Reducing force and repetition by using power tools (when appropriate)
- Trying to redesign tasks that require repeated, forceful hand and tool use
In addition:
When possible, position work in front at about waist height.
Understand the importance of smart lifting:
- Train/learn how to use a hand truck (or get help) with large loads.
- Avoid bending and twisting the back when lifting.
- Bend at the knees and keep back straight to lift loads from the floor.
- Lift like a baby. (Watch two-year-olds lift something off the floor: They use perfect posture, squatting down using the strength of their legs to balance and lift.)
- Try to design work so that loads are lighter, heavy loads are stored at waist height, and less lifting is required.
- Change the size or weight of the load to accommodate differences in strength.
More than 2,000 studies on musculoskeletal disorders have been conducted by the Centers for Disease Control and Prevention (CDC) and the National Institute for Occupational Safety and Health (NIOSH). (2) In addition to making environmental changes (at home and on the job), the findings indicate that exercising, stretching, and physical balance are critical components to minimizing the potential for musculoskeletal disorders. Based on the research, circumstances that lead to musculoskeletal disorders are most likely multiple in origin.
It’s important to note that NIOSH and the CDC have also identified individual (personal) factors associated with work-related musculoskeletal disorders (MSDs). It’s important to note that the relationship of these individual factors and the resulting risk of injury to an individual are complex and not yet fully understood. Among these factors are:
- Gender. Some studies have found a higher prevalence of some MSDs in women.
- Cigarette smoking. Some studies have found smoking related to pain in the extremities, including the neck and back. One hypothesis is that there is nicotine-induced diminished blood flow to vulnerable tissues.
- Physical activity. A lack (or overexertion) of physical activity may increase susceptibility to injury.
- Strength. The risk for musculoskeletal injuries (in some studies) was three times greater in weaker subjects.
- Anthropometry. Weight, height, body mass index (BMI) (a ratio of weight to height squared), and obesity all can play a role in MSD potential, especially carpal tunnel syndrome and lumbar disc herniation.
In a number of musculoskeletal injury cases, basic ergonomic changes (such as adjusting chairs, desks, and other equipment) alone may have minimal impact on the final outcome of an individual’s health and musculoskeletal injury recovery for two reasons. First, as shown in Exhibit 4.2, activities at work constitute about 24 percent of your life activities (based on a 40-hour workweek), and second, the best success seems to come from continuing to incorporate personal exercise, stretch activities, and functional posture at home and at work. As time away from the job constitutes so much of our life activities, obviously it is vital to examine away-from-work ergonomic/fitness activities.
Exhibit 4.2 Real Time on the Job versus Off the Job
References:
Kate Montgomery, End Your Carpal Tunnel Pain Without Surgery (Boulder, CO: Sports Touch Publishing, 2004), and Anthony Carey, The Pain-Free Program (Hoboken, NJ: John Wiley & Sons, 2005).
2 U.S. Department of Health and Human Services, “Musculoskeletal Disorders and Workplace Factors: A Critical Review of Epidemiological Evidence for Work-Related Musculoskeletal Disorders of the Neck, Upper Extremity, and Low Back,” July 1997
Steve Thompson is president of Aspen Risk Management Group and ERGOhealthy. Contact Steve at: 619-294-9863 or www.ergohealthy.com, or www.aspenrmg.com