Slips, trips and falls on the level are considered commonplace and are rarely subjected to in-depth analysis. They occur in highly varied circumstances in an occupational situation. In-depth analysis of these accidents was conducted within a company with the aim of understanding them better, to be able to discuss prevention field possibilities and priorities for the company concerned. Firstly, available data on 'accidents on the level' occurring over the last 4 years were analysed and a typology for these accidents was derived, based on individual activity at the time of the accident and accident location. The three most serious accident-causing situations were analysed in-depth from interviews with injured persons, as well as from activity observation and activity-related verbal information obtained from operatives. These most serious situations involved accidents occurring when climbing down from trucks or when walking either in surroundings outside company premises or from (to) a vehicle to (from) a work location. In-depth accident analysis and characterization of accident-causing situations as a whole enhance our understanding of the accident process and allow us to envisage priorities for action in the prevention field, in operational terms. Each accident-causing situation reveals environmental factors that in fact constitute accident factors (obstacle, stone, etc.), when the individual walks or climbs down from a truck. Analysis shows that other events are necessary for accident occurrence. For example, the individual may be subjected to a time constraint or may be preoccupied. Results obtained here, in a company integrating different trades, are discussed and compared with those referred to in the literature. Generalization of some of these results is also considered.