Assessment of well-being in a Crypt with microclimatic, air quality and radon exhalation investigations

We studied the microclimatic and air quality conditions inside the crypt of the cathedral of Otranto (south-east of Italy), which is under the ground level, in order to state if health and well-being conditions are satisfied for tourists and fellows. In particular, we analyzed the heat transfer mechanism and the relative humidity to state the comfort of the environment, applying the Fanger index. The presence of artificial and human pollutants was monitored, respectively, inspecting the carbon monoxide and dioxide concentration. The crypt and the cathedral showed an acceptable state, even during ceremonies when there is crowding inside the crypt. More worrying were the levels of radon concentration, steadily over 500 Bqm−3, which constitute a serious threat for the health of workers and visitors. A continuous control during one year was performed, using E-PERM passive electret dosimeters and taking into account troubles connected to the presence of outliers that appear sometimes when using electrets, especially in high-level humidity habitats like crypts.