This theoretical paper discusses de appropriateness of including the concept of variability into projects of automating work stations. It underlines the contribution of ergonomics to the process of introducing new technologies, which not only modify the nature of the work but frequently the health of the worker as well. The variability of work, a consequence of the difference between prescribed norms and reality, may be understood based on (a) the characteristics of the worker, stressing the notion of inter- and intrapersonal variability, (b) the organization of the work process, stressing the variability of equipment, materials and procedures. By taking variability into account when elaborating a project or a situation of technological innovation, it renders favourable improvement in working conditions due to flexibility and reduction of impositions of prescribed work norms, which usually are based on a `mean' worker, well trained and working under stable conditions.
ergonomics; variability; new tecnologies