FIRST NATIONAL COMPARISON ON RADON ACTIVE MONITORS AT ENEA-INMRI

This is the first Italian interlaboratory comparison (ILC) on active radon monitoring organized by the National Institute of Ionizing Radiation Metrology of ENEA (ENEA-INMRI). The ILC was financed by the Ministry of Economic Development (MiSE). The objective is to investigate the quality of radon measurements carried out by operators in the sector and improve their performance. Participants were asked to determine radon exposure in air over a time interval in which the radon concentration was varied over a wide range from approximately 500 to 5500 Bq/m3. The results were analyzed using the relative percentage difference D (%) and the normalized error En. Over 65% of the results fall within the range of En < 1. Most of the deviations were detected when the instruments were not calibrated correctly.