ABSTRACT
Industrial activity around the world is performed by two-thirds of the world population over 10 years of age spending one third of their lives on work (WHO, 1995). This enormous workforce, through its contribution, generates a wealth of 21.3 trillion U.S. dollars, which sustains the socioeconomic fabric of the international society. Given the uneven distribution of population between developed and developing countries, a large majority of humanity is resorting to mechanical force application to accomplish their tasks. Additionally, in spite of the progression of technology, there are a great number of jobs in developed countries that require muscle force application (e.g., mining, forestry, agriculture, drilling and exploration, manufacturing and service sector). In many recreational activities and
sports, as well as industry, force application is the primary requirement after skill. Thus, force application is essential to getting things done, more in some activities than others. The quantity, duration, and frequency of force application at a job provide an essential tool to gauge the job demands. A determination of such demands, when compared against the worker's ability to exert force (strength), provides ergonomists a meaningful measure of stress on workers. Even in developed countries a large number of tasks are not automated, due to the cost and complexity. Consequently, the responsibility of strength exertion falls on the workers. It has been estimated that, in order to produce one ton of product, a worker has to lift or manually handle anywhere between 80 and 320 tons of raw materials. Workers in an industrial economy are a very important resource, and for industrial health, they must be protected. The values for strength requirement and strength available are important data, which need to be used in job design for worker health and safety and industrial productivity.
