Go IWASHITAー ーーーーーー * 1 Indoor air environment audit in school classrooms with open-space, classrooms with semi-open-space, and traditional classrooms without open-space was conducted seasonally in six elementary schools in Tokyo city area, Japan. During the summer season measurement, CO2 concentrations in the classrooms with open-space tended to be lower than those in the traditional classrooms without open-space, since the open-space type classroom had rather larger air volume. In French school IAQ study, the ICONE (Indice de CONfinement d'air dans les Ecoles) index was used to evaluate air stuffiness during occupied periods. The ICONE index might be useful for estimating the difference on air environmental factors among different classroom types.