Despite all related studies and research efforts, radon gas emissions and their impact on human health remain relatively unknown to the general public. The World Health Organization (WHO) estimates that radon is at the origin of 3–14% of all lung cancers and, although WHO recommendations to tackle indoor radon exposure are progressively paving the way, most implemented measures have not been effective, so we need new approaches to increase public awareness and reduce harmful effects of radon. Awareness will be leveled by prioritizing a citizen science-based approach, which involves advocating for a participatory process that encourages the active involvement of citizens in scientific data collection. In the context of this research, we are developing a citizen science-based web platform that collects relevant data related to indoor radon concentration. On the web platform, all citizens are encouraged to participate in a pre-diagnosis procedure to assess the radon potential existing in the buildings they live or work in. An automated classification model assesses the potential for indoor radon gas and outputs a pre-diagnosis result in three categories: low, medium, or high risk. Thus, while raising awareness of radon risk, we can provide newly qualified data for indoor radon exposure research.