Integration of the envelope permeability measurement into the outdoor/indoor pollutant transfer process.

The study forms part of a research project performed by LEPTAB and ATMO Poitou-Charente within PRIMEQUAL program which targets the relation between the indoor and local outdoor pollution. According to many studies, outdoor pollution has a major influence on indoor air quality, airflow being the main factor linking the outdoor environment directly to the climate indoors. A precise regulation of the air flow entering the room is enabled by the mechanical ventilation system and this makes possible the control of the indoor air pollution concentration. In contrast, air infiltration through the building facade is an uncontrollable parameter, with an important effect on the phenomenon of pollutant transfer. The authors present envelope airtightness measurements performed in several La Rochelle schools. Secondly, they use the permeability laws to determine the airflow crossing the envelope as a function of the indoor/outdoor pressure difference during the continuous measurements of pollutant concentrations and in order to assess its influence on indoor air pollutant concentrations.