This research is one of the few studies that focused on the prevention of musculoskeletal disorders (MSDs) in terms of time organisation of work and determinants related to public policies and ministerial instructions. The objectives were to provide a picture of the temporal requirements of seasonal work and to identify determinants of work situations for sustainable prevention of MSDs. Based on an analysis of work activity from a gender perspective, 16 seasonal workers in the crab processing industry were followed for two consecutive years. Various interviews, observations (activity, production and organisation of work) and analysis of documents were carried out. The results highlight the importance of women’s job constraints in this sector, the partial and incomplete portrayal of production data to understand the time constraints of female workers, as well as the significant impact that public policies can have on the work of female workers. The study proposes methodological elements for the analysis of the temporal organisation of work.