The Regional Air Quality Plan (PRQA), established under the Law on Air Quality and the Rational Use of Energy of December 30, 1996, and whose implementation procedures are specified by the Decree of May 6, 1998, sets out guidelines aimed at preventing, reducing, or mitigating the effects of air pollution. It is based as much as possible on an assessment of the effects of air quality on public health. The Nord-Pas-de-Calais PRQA is divided into 54 guidelines. The fifteenth guideline states that “conducting studies for the local assessment of the health impact of air pollution in the main urban areas of the Nord-Pas-de-Calais region covered by a monitoring network” is considered a priority. It is within this framework that the health impact assessment (HIA) of air pollution in Calais is being conducted. The value of a health impact study would provide local stakeholders (decision-makers, associations, residents, etc.) with an order of magnitude of the impact of air pollution in order to set air quality improvement targets based on public health criteria. It also serves as a tool for planning and evaluating public policies, as it allows for the measurement of the effectiveness of preventive measures. It follows the health impact assessment methodology updated by the InVS, in accordance with WHO recommendations. The short-term health impact of air pollution is calculated in terms of morbidity (hospital admissions) and excess mortality. An estimate of the long-term health impact is calculated in terms of mortality using the results of international epidemiological studies. The main objective of this work is to assess the feasibility of a health impact study of air pollution in the Calais region: that is, to verify the conditions necessary for conducting this study, including the characteristics of the study area, the availability of data for exposure estimation, and the availability of health data.