The quality of the air we breathe indoors is now recognized as a key factor in the rising incidence of various chronic conditions and respiratory allergies. In industrialized countries, people spend a significant portion of their time indoors, such as in their homes. Quantifying the time spent at home is therefore an important factor in estimating exposure to indoor pollutants. Studies on time-use surveys (TUS) are relatively scarce in France. The objectives of this study are to estimate the distribution of time spent indoors by the French population and their exposure to carbon monoxide (CO), benzene, and formaldehyde by linking the concentrations of these pollutants with TUS data. The data used were collected by the Indoor Air Quality Observatory between October 2003 and December 2005. On average over the week, the time spent daily indoors is 16 hours and 10 minutes. This represents 67% of daily time (71% for women and 63% for men). Overall, the population’s average exposure to CO is low. It is consistently higher in winter (avg.=0.5 ppm; max.=7.5 ppm) than in summer (avg.=0.2 ppm; max.=3 ppm). Exposure to formaldehyde and benzene in the bedroom is slightly higher in summer for formaldehyde and the opposite is true for benzene. The BET data provide a useful source of information for improving estimates of population exposure to indoor pollutants and for quantitative health risk assessments. (R.A.)