This paper describes two studies about petroleum industry. The first was developed in a refinery and the second focuses on the work of operators in various jobs within a refinery and maritime petroleum units. In both cases, the focal point was the analyses of activities, that is, what the workers do and how they do it in order to meet production demandai put on them. However, two different methods were applied in the studies. Ergonomics Work Analyses (EWA) was used on the first case and Collective Work Analyses (CWA), on the second. Besides showing the main results, the author compares the two methods. She also draws the scientific community attention to the importance of studding the workers actual activity in order to contribute to a better understanding of what is going on inside production units, avoiding useless human suffering, and the still ocurring undustrial disasters.
petroleum workers; work analyses; activities in work situations; unsafe work; complex work; shift work and collective work