In nuclear facilities, airborne particles are the vector of most of the radiological contamination. For this reason, pleated HEPA filters are one of the containment devices which are actively studied by the IRSN (Institut de radioprotection et de sûreté nucléaire) to ensure the safety of nuclear exploitation. To avoid contamination of the environment, the understanding of the behavior of the filters especially in accidental situation has to be as exhaustive as possible. The most probable accident and the most penalizing for the containment devices is fire which leads to a massive soot particle production. In this case, the clogging of the filters os a problematic which has to be taken into account. Up to now, an empirical correlation has been developed to predict the pressure drop increase. The empirical nature of this correlation does not allow its use in all situations. A phenomenological understanding and model of the clogging is then necessary. The following PhD work aims to reduce the pressure drop evolution to physical observations for each step of the clogging in order to model it on the most physical basis as possible. To do so, the study has been divided in two parts. The first one focusing on the behavior of flat filter by measuring the penetration of particles inside the medium and the porosity of the deposit formed on its surface. In the second part, a small scale experiment based on a single pleat has been developped. Accumulation of the particles inside the pleat has been directly observed, deformation of the pleat as well as airflow in the pleat (using a PIV method) has been measured. During these experiments, pressure drop has been monitored and the measured parameters have been linked to the pressure drop evolution. Finality is to build a simple analytical model to predict the pressure drop evolution of the filters as a function of the deposited mass, the aerosol characteristics and the ventilation conditions. The main perspective opened by theses results is the validation of complete numerical models to overcome the experimental limits. The logical extension of this work will be the study of the interaction of a clogged filter with temperature, air moisture and chemical aggression.