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IntroductionBuildings that constitute cultural heritage and that are the identity of a defined geographical area are increasingly being restored to offer the community historical places to enjoy. Often the restoration preserves the original structure and building materials, which are usually natural stones. In this study, a radioprotection protocol dedicated to this kind of built environment was proposed and validated.MethodsAfter identifying the two predominant types of building material stones (Rosso ammonitico and Pietra Serena), radiometric measurements for natural gamma-emitting radionuclides (Ra-226, Th-232, and K-40) and measurements of the emanation coefficient and calculation of the exhalation rate of radon gas were carried out.ResultsThe two types of stone have a content of natural radionuclides that do not exceed the levels recommended by the regulations. The difference between the two types of stone is of an order of magnitude indicating that the red ammonite has a greater radiological impact than the pietra serena.DiscussionThe results, in addition to ensuring the radioprotection of the population, highlighted the need to increase the number of this kind of investigations to implement scientific knowledge and serve the stakeholders involved.

Introduction: Risk assessment of exposure to indoor pollutants plays an increasingly important role in human protection, and one of the main sources of indoor pollutants is building materials (BMs). In addition, production processes, including those related to BMs, are also involved in economic transition: the use of by-products from other industrial sectors as raw materials for the production processes in compliance with environmental sustainability is evaluated.Methods: In this work, we evaluate not only the radiation protection of BMs but also the possibility of adopting the circular economy principles. The two main objectives of this study were 1) radiometric characterization and calculation of Index I of pozzolan from Altavilla Irpina (Avellino) in Italy, used as a natural igneous additive for concrete, using gamma spectroscopy, and 2) comparison of different methodologies for calculating the annual effective dose of BMs (CEN/TR 17113:2017, RESRAD-BUILD software, and a previously developed experimental method). The same approach was extended to the possibility of reusing fly ash—a naturally occurring radioactive material (NORM) by-product of coal combustion in thermal power plants—for the production of concrete.Results and Discussion: The study aligns with the principles linked to the circular economy to extend the life cycle of materials by reducing the need for natural resources, suggesting a possible positive compromise between radioprotection and preservation of environmental heritage.

Radon gas is one of the chemical pollutants with one of the most significant physical effects due to its impact on human health: it is a radioactive noble gas which, if inhaled, can stochastically induce lung cancer. For this reason, it is classified as a category A substance and is the second cause of cancer after tobacco smoking. The monitoring and management of indoor radon is based on international recommendations but also national regulations, which, in recent years, have been updated by lowering the reference levels. In this work, some radon activity concentration data were evaluated by comparing the criteria of old and new legislation to highlight how the radiation protection approach has completely changed. Specifically, this study focuses on measurements in Campania, which, due to its originally volcanic geological structure, requires crucial attention in the context of radon risk assessment, given the considerable number of dwellings built in tuff. This initial data processing enabled the identification of potential high-priority radon risk areas, serving as an important reference point for the extension of the monitoring activities in Campania.

Radon, a radioactive inert gas that comes from the decay of naturally occurring radioactive species, poses a substantial health risk due to its involvement in lung cancer carcinogenesis. This work proposes a metrological approach for determining radon exhalation rates from diverse building materials. This methodology employs an electrostatic collection chamber for alpha spectrometry of radon isotopic decay products. Experimental evaluations were conducted particularly focusing on volcanic gray tuff from Sant’Agata de’ Goti (Campania region, Italy), a material commonly utilized in construction, to assess radon exhalation rates. The study aligns with Legislative Decree 101/2020, a transposition of European Directive 59/2013/Euratom, highlighting the need to identify materials with a high risk of radon exhalation. Moreover, this work supports the goals of the Italian National Radon Action Plan related to the aforementioned decree, aiming to develop methodologies for estimating radon exhalation rates from building materials and improving radioprotection practices.

Outreach projects are often used to a limited extent for dissemination purposes and rarely have a significant impact on the student’s teaching and technical skills. The RadioLab project requires a proactive interaction between researchers and students by experimental activities for measuring environmental radioactivity, in particular radon gas. Buildings considered to be of radiological interest, such as schools, have been selected to carry out radon gas activity concentration measurements using solid-state nuclear track passive detectors LR-115. The results of annual measurements, made over 6 years and involving a total of 952 rooms, distributed in 67 schools throughout the Campania region, were collected. These data, deemed scientifically reliable (i) can be overlapped over geological characterization data enhancing the relationship between lithology and radon, (ii) confirmed data from the radon potential map of the Campania region about the distribution of indoor radon, and finally (iii) contributed to the collection of radon indoor data of the Campania region. The results obtained highlighted the need and effectiveness of increasing the network of schools involved in the outreach activity and in the implementation of experimental activities with applicative effects in the scientific and research sectors.

The analysis of the Earth's rotation rate time series, from January 1,2012 till December 31,2017, is performed using two different time series analysis methods, both based on signal decomposition joined with forecasting approach. Anomalies in the time series are detected making the comparison between the raw signal and the forecasting one at the 95% confidence interval. The two methods show consistent results and the best is selected according to the evaluation of the prediction uncertainty. Both methods highlight correlations between detected anomalies in the Earth's rotation rate time series and the world's earthquakes occurrence with magnitude ≥7 and/or number of events ≥150 per day, within a time interval of ±10 days from each earthquake event. This study brings an innovation in the analysis of such time series and helps to better understand the extent of this relationship. Keywords: Earth's rotation rate, Time series analysis, Anomalies detection, Earthquake

Neutrons constitute a significant component of the secondary cosmic rays and are one of the most important contributors to natural cosmic ray radiation background dose. The study of the cosmic ray neutrons’ contribution to the dose equivalent received by humans is an interesting and challenging task for the scientific community. In addition, international regulations demand assessing the biological risk due to radiation exposure for both workers and the general population. Because the dose rate due to cosmic radiation increases significantly with altitude, the objective of this work was to characterize the thermoluminescent dosimeter (TLDs) from the perspective of exposing them at high altitudes for longtime neutron dose monitoring. The pair of TLD-700 and TLD-600 is amply used to obtain the information on gamma and neutron dose in mixed neutron-gamma fields due to the present difference in 6Li isotope concentration. A thermoluminescence dosimeter system based on pair of TLD-600/700 was characterized to enable it for neutron dosimetry in the thermal energy range. The system was calibrated in terms of neutron ambient dose equivalent in an experimental setup using a 241Am-B radionuclide neutron source coated by a moderator material, polyethylene, creating a thermalized neutron field. Afterward, the pair of TLD-600/700 was exposed at the CERN-EU High-Energy Reference Field (CERF) facility in Geneva, which delivers a neutron field with a spectrum similar to that of secondary cosmic rays. The dosimetric system provided a dose value comparable with the calculated one demonstrating a good performance for neutron dosimetry.

Using Monte Carlo (with Geant4) and COMSOL simulations, the authors have defined a useful tool to reproduce the alpha spectroscopy of 222Rn, 220Rn and their ionized daughters by measurement systems based on electrostatic collection on a silicon detector, inside a metallic chamber. Several applications have been performed: (i) simulating commercial devices worldwide used, and comparing them with experimental theoretical results; (ii) studying of realization of new measurement systems through investigation of the detection efficiency versus different chamber geometries. New considerations and steps forward have been drawn. The present work is a novelty in the literature concerning this research framework.

The study concerns the analysis of 220Rn (thoron) recorded in the surface soil in two sites of the Campi Flegrei caldera (Naples, Southern Italy) characterized by phases of volcanic unrest in the seven-year period 1 July 2011–31 December 2017. Thoron comes only from the most surface layer, so the characteristics of its time series are strictly connected to the shallow phenomena, which can also act at a distance from the measuring point in these particular areas. Since we measured 220Rn in parallel with 222Rn (radon), we found that by using the same analysis applied to radon, we obtained interesting information. While knowing the limits of this radioisotope well, we highlight only the particular characteristics of the emissions of thoron in the surface soil. Here, we show that it also shows some clear features found in the radon signal, such as anomalies and signal trends. Consequently, we provide good evidence that, in spite of the very short life of 220Rn compared to 222Rn, both are related to the carrier effect of CO2, which has significantly increased in the last few years within the caldera. The hydrothermal alterations, induced by the increase in temperature and pressure of the caldera system, occur in the surface soils and significantly influence thoron’s power of exhalation from the surface layer. The effects on the surface thoron are reflected in both sites, but with less intensity, the same behavior of 222Rn following the increasing movements and fluctuations of the geophysical and geochemical parameters (CO2 flux, fumarolic tremor, background seismicity, soil deformation). An overall linear correlation was found between the 222−220Rn signals, indicating the effect of the CO2 vector. The overall results represent a significant step forward in the use and interpretation of the thoron signal.

222Rn gas represents the major contributor to human health risk from environmental radiological exposure. In confined spaces radon can accumulate to relatively high levels so that mitigation actions are necessary. The Italian legislation on radiation protection has set a reference value for the activity concentration of radon at 300 Bq/m3. In this study, measurements of the annual radon concentration of 62 bank buildings spread throughout the Campania region (Southern Italy) were carried out. Using devices based on CR-39 solid-state nuclear track detectors, the 222Rn level was assessed in 136 confined spaces (127 at underground floors and 9 at ground floors) frequented by workers and/or the public. The survey parameters considered in the analysis of the results were: floor types, wall cladding materials, number of openings, door/window opening duration for air exchange. Radon levels were found to be between 17 and 680 Bq/m3, with an average value of 130 Bq/m3 and a standard deviation of 120 Bq/m3. About 7% of the results gave a radon activity concentration above 300 Bq/m3. The analysis showed that the floor level and air exchange have the most significant influence. This study highlighted the importance of the assessment of indoor radon levels for work environments in particular, to protect the workers and public from radon-induced health effects.