Occupational Ergonomics: Principles and Applications

This chapter provides the basic principles that underlie the field of ergonomics and their application to some of the current issues of importance in the workplace. Sections 2 to 4 deal with the physiology of muscles; biomechanics; cellular responses to tissue, nerve, and joint injuries as they relate to cumulative trauma disorders; and common types of overuse syndromes. The remaining sections deal with applications of the principles to workplace ergonomic issues and proposed ergonomic regulations. The word “ergonomics” is made up of two Greek words, “ergo” meaning work and “nomas” meaning laws. The field of ergonomics is highly interdisciplinary. It applies principles from engineering, physiology, medicine, and psychology to the understanding of the interaction of humans with their workplace. The interaction of humans with their workplace may consist of identifying the relationship between job physical risk factors and physiological responses. For example, a specific ergonomic problem of paramount importance in the occupational health and safety is the issue of work-related musculoskeletal disorders (WMD). Some of these issues are discussed further in this chapter. The specific areas of application relevant for the field of ergonomics are defined and briefly explained. Activities that involve repetitive stress have effects that are extremely complicated. Adding internal or external forces to the body can, as described, alter bone, joints, ligaments, tendons, nerves, and muscles. Belief that a repetitive motion will result in an isolated nerve injury without affecting surrounding joints, ligaments, muscles, or tendons is likely to inhibit appropriate care and control of exposed individuals. Additional research is needed to further characterize changes that occur, and current approaches to recognizing, managing and preventing repetitive injuries must address all tissues in the involved area. Keywords: Principles; Ergonomics; Muscle; Skeletal system; Anthropometry; Biomechanics; Physiological effects; Stress strain; Tissue injury; Bone; Joints; Ligament; Tendon; Nerve; Upper extremity overuse; Carpal tunnel; Low back pain; Low back loads; Regulations; California standards; ANSI Z-365; Job analysis

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