Federica Leonardi

A new accurate and flexible index to assess the contribution of building materials to indoor gamma exposure

The role of building materials as a source of gamma radiation has been recognized in the new EU Basic Safety Standards Directive which introduces an index I to screen building materials of radiological concern. This index was developed to account for average concrete values of thickness and density, the main structural characteristics of building materials that have an effect on gamma irradiation. Consequently, this screening procedure could be unfit in case of significantly different density and/or thickness of the building materials under examination. The paper proposes a more accurate and flexible activity concentration index, accounting for the actual density and thickness of building materials.

Indoor radon levels in schools of South-East Italy

A survey was conducted to evaluate average levels of indoor radon and gamma doses in all educational buildings (506 schools) located in South-East Italy (the Salento peninsula, province of Lecce). In this paper the final findings relating to measurements performed with SSNTD dosemeters in 438 schools (86% of the sample) are reported. The average annual activity concentration of radon in schools located in the province of Lecce is 209 ± 9 Bq/m(3). Radon values actually ranged from 21 Bq/m(3) to 1608 Bq/m(3). About 7% of schools showed radon concentration values above 500 Bq/m(3), the Italian action level for workplaces.

Development of a framework of quality assurance practices for a radon passive dosemeter service

Etched track detectors are widely used for the detection of radon and its decay products. The reliability of radon measurement performed with such devices requires that laboratories producing analytical data are able to provide results of the required quality. The need for uniform results from laboratories at an international level therefore requires the implementation of a quality assurance programme, the harmonization of criteria, sampling procedures, calculations and the reporting of results, agreed on the basis of fundamental principles and international standards. The quality assurance programme described here is the first step on the way to ISO/IEC 17025 certification for the RI-RN (ISPESL) laboratory.

Updated database on natural radioactivity in building materials in Europe

The paper presents the latest collection of activity concentration data of natural radionuclides (226Ra, 232Th and 4 K) in building materials. This database contains about 24200 samples of both bulk materials and their constituents (bricks, concrete, cement, aggregates) and superficial materials used in most European Union Member States and some European countries. This collection also includes radiological information about some NORM residues and by-products (by-product gypsum, metallurgical slags, fly and bottom ashes and red mud) which can be of radiological concern if recycled in building materials as secondary raw materials. Moreover, radon emanation and radon exhalation rate data are reported for bricks and concrete.

Metrological aspects of international intercomparison of passive radon detectors under field conditions in Marie Curie’s tunnel in Lurisia

Abstract In 2014, an intercomparison exercise of passive radon detectors under field conditions in the Marie Curie’s tunnel belonging to the Lurisia spas complex (Lurisia, Piedmont, Italy) has been held. Radon activity concentration in the tunnel was measured with six radon active monitors, previously calibrated at ENEA-INMRI facilities. In the present paper, a synthesis of the metrological aspects of the intercomparison is given. Indeed particular attention was paid to metrological characterization of radon monitors and their response upon ambient conditions. Correction factors have been defined to be applied when measurements are performed in severe environmental conditions. In particular, it has been found that monitors are particularly sensitive to the effect of air density: the AlphaGUARD (AG-SAPHYMO, GmbH) efficiency decreases with the air density, while for the MR1 PLUS (Tesys, Italy), the opposite applies. When the reference monitors were placed into the Marie Curie’s tunnel, to the recorded average radon concentrations correction factors were applied. After the correction the difference between data coming from AG and MR1 PLUS is within the 1.7%.