With better insulations of buildings, indoor air pollution is becoming a growing concern for human well-being and human health. Today ther is no easy way to determine in real-time indoor air quality because of two main reasons:

(i) There are thousands of pollutants in indoor air with diverse impacts on human comfort, health and safety

(ii) The concentration of these pollutants are generally very low (fow ppb)

In order to monitor Indoor Air Quality, one can use relatively low cost sensors that give an estimation of the amount of pollution in situ and in real-time but without discriminating harmful pollutants from non-harmfull pollutants. It is thus difficult to give accurate advices to reduce the level of indoor pollution.Another way is to sample air and analyze the samples in laboratories with very sensitive but also expensive devices. The last case presents the following drawbacks:

(i) It takes time;

(ii) It is costly: few thousands euros per building;

iii) It requires a specialist operator to identify the pollution origin.

Here, we propose a new way to perform fast, low-cost indoor air quality diagnoses at high added value in buildings by using an innovative photo-acoustic analyzer. Diagnosis results can be obtained in less than an hour and emission sources can be subsequently located.