Knowledge is a core element of public policies on risks. Risks and knowledge are strictly bidden mainly through information systems tracing the characteristics of the risk at stake, its dynamics and as support to built interventions. The knowledge of risk is reformulated in this work not as aprioristic knowledge provided by the instrument but as knowledge produced in its situated use with other elements of the contexts. Based on a wildfire forecast system, the author’s analysis focuses on how these dispositives are used by contextual users in the daily practice of risk prevention and management. It is through daily practices of use of the instrument that the risk becomes visible, accountable and workable. Risks would be then analyzed not as given but rather as emerging from contextual work practices.
Keywords: knowledge, risks, work practices, wildfire