Abstract
Most safety professionals are concerned with the human factors and the aging population. When asked why they are concerned, many express fears of anticipated increases in injury rates as their working population ages. However, data suggests that non-fatal occupational injury rates (sprains and strains) are higher for younger workers (≤ 25 years old) compared to the ageing population (Jackson, 2001; Salminen, 2004). This is especially true for male populations.
In reality, the two most important issues safety professionals should consider as the workforce ages are:
Decreases in production performance - Older workers often require increased task completion time, which leads to decreases in production performance (Rahman et al., 2002).
Increases in quality errors - Many older workers experience reduced hand sensitivity, which results in reduced tactile sensation and more product assembly errors (Ranganathan et al., 2001).
Currently, many organizations understand the positive impacts of human factors engineering on productivity performance (for example, lean manufacturing). Organizations have repeatedly demonstrated task time improvements and ergonomic risk reductions following the implementation of engineering/ergonomic improvements. However, very few have launched ergonomic initiatives focused on reducing quality errors. Poor facility designs lead to quality issues, and Eklund (1999) showed that 60-70% of work-related musculoskeletal disorders (WMSDs) are related to poor design.
As we age, design is increasingly important since significant physiological changes occur that exacerbate the potential for WMSDs and quality errors. These physiological changes include, but are not limited to:
Movement speed slows during grasping (Carnahan et al., 1993) and reaching (Seidler-Dobrin and Stelmach, 1998)
Movement precision (deceleration) decreases (Walker et al., 1997)
Range of motion is reduced (Chaparro et al., 2000)
Muscle strength (grip, push, pull) decreases (Ketchum and Stelmach, 2001)
Force control decreases, as adults grip twice as hard to compensate (Cole, 1991)
Force perception decreases (Cole et al., 1991)
Muscle endurance decreases
In this article, readers will learn how to identify human factors concerns using scientific tools, as well as human factors design guidelines to accommodate the aging population.
