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A systematic study of the distribution of the Naturally Occurring Radioactivity in stone dust and crushed stone, has been carried out with an objective of establishing reliable baseline data on the radiation level and hence to evaluate hazard indices approach and the production of radioactive heat (RHP) due to radiation exposure to the workers and to the inhabitants of the studied area. Twenty-six samples have been collected from different locations in the State of Rio de Janeiro (Brazil). To calculate the specific activity, gamma ray spectrometry and a detector of High Purity Germanium (HPGe; Canberra, 30% relative efficiency) was used. The activity concentration of 238U, 226Ra 232Th and 40K ranged from 29.3 ± 18.6 to 206.8 ± 21.5 Bq kg−1, 30.3 ± 1.0 to 134.3 ± 1.8, 27.9 ± 0.7 to 86.2 ± 0.9 Bq kg−1, and 734.9 ± 35.1 to 1204.8 ± 53.5 Bq kg−1, respectively. The mean values of the I ex , I in , I γ , I α , A UI , I RP112Rn , I PA , I PI and I Yu indices were 0.68 ± 0.09, 0.92 ± 0.12, 0.93 ± 0.12, 0.43 ± 0.07, 0.88 ± 0.20, 1.25 ± 0.21, 0.34 ± 0.05, 0.75 ± 0.10, 0.63 ± 0.08 and 34. ± 6.31, respectively. The average radioactive heat production (RHP) of 2.01 ± 0.28 μ Wm−3 was above the values found in the literature, which may contribute to the heat flow in the study area because the raw materials that make up the samples showed a high value of environmental radioactivity. The Brazilian Hazard Index to assess the radiological risk of crushed stone and stone dust was created and the average value was 0.74 ± 0.10, a value below 1, which means only moderate control over the use of these materials, with no indication of restriction to the its use. • High-res gamma spectrometer measured levels of natural radionuclides in stone dust, crushed stone. • Study assesses radionuclide exposure risks in building materials, safety for workers & residents. • Research helps build database to minimize ionizing radiation damage, inform public policy. • A Brazilian Risk Index for samples was created to better adapt to the reality of using these materials in Brazil. [ABSTRACT FROM AUTHOR]

Brazil is the fourth largest cement consumer in the world and the largest producer in Latin America, around 1.3% of global production. The main inputs in the manufacture of cement are limestone and clay. Few studies have been carried out in the country on the risk of these materials used in civil construction. Therefore, the objective of this present work is to evaluate the radiological danger that they can present to society. Gamma spectrometry analysis on 16 samples of different brands of cement used as construction material in Rio de Janeiro (Brazil) was performed in this study, using an HPGe detector and the Genie 2000 data acquisition software. Samples were set to count for an accumulation time of 14,400 s (4 h) and all measurements were corrected to eliminate background and backscattering. Activity concentrations are determined for 226Ra was from (41.2 ± 1.6 to 174.9 ± 3.9) Bq kg−1, 232Th was from (15.7 ± 0.5 to 43.1 ± 0.7) Bq kg−1 and 40K was from (82.6 ± 7.2 to 254 ± 17) Bq kg−1. To assess radiological health risks: mean values of Radium Activity Equivalent 150.0 ± 3.4 Bq kg−1, Annual Gonadal Dose Equivalent 468 ± 11 μSv year−1 and Lifetime Excess Cancer Risk (ELCR) 2.42 ± 0.06 were calculated. Total Absorbed Dose Rates ranged from 72.2 ± 1.7 to 225.1 ± 5.2 nGy h−1. The damage to collective health was also estimated from the annual effective dose rates with an estimated total cost of damage to health of US$ 130 million. Values are generally within global limits reported by UNSCEAR. • Rio cement study: low radioactivity, minimal health risk from indoor gamma dose. • Gamma spectrometry on Rio cement brands for radiological assessment. • 226Ra, 232Th, 40K in Rio's cements within world averages for building materials. • Radiological hazard assessment of Rio cement shows safety within global norms. • Study on cement's radiological risk in Rio covers annual dose, cancer risk. [ABSTRACT FROM AUTHOR]

The presence of naturally occurring radioactivity in sand and other building materials results in indoor and outdoor exposure to the public. Sand is one of the main components in civil construction alongside cement, crushed stone and bricks. Thus, this research was carried out in twenty sand samples with the objective of investigating the hazard indices of natural radiation, due to the presence of 238U, 226Ra, 232Th and 40K in sand samples collected in some locations in the state of Rio de Janeiro (Brazil), analyzing by gamma spectrometry and using an HPGe detector. The technique used for gamma analysis was gamma spectrometry, and the software used to analyze peaks and obtain counts was LabSOCS. In this context, the average activity concentration values of 226Ra (66.7 ± 1.2) and 40K (647 ± 31) Bq kg−1 are higher than the world mean activity concentration of 50, 50 and 500 Bq kg−1 for these three radionuclides. However, the value of 232Th (40.6 ± 0.7) Bq kg−1 and Raeq (175 ± 5) Bq kg−1 are less than the world average of 50 Bq kg−1 and 370 Bq kg−1, respectively. The estimation of the average values for Annual Effective Dose (0.51 ± 0.01) and Dutch Radiation Performance Index (0.52 ± 0.01) was carried out, with values below the maximum recommended limit for the public. Only one sample had a higher value and the other samples are within the levels required for environmental control. However, the mean values found in this present study, when compared to those of other authors mentioned here, showed higher values. Therefore, most samples have safe values to be used by people in building their homes. • Study on natural radioactivity in Rio's construction sand reveals public health risks. • Samples sand analyzed shows high 238U, 226Ra, 40K but low 232Th compared to global norms. • AR7 sand sample in Rio exceeds safe radiation limits, highlighting need for controls. [ABSTRACT FROM AUTHOR]

Paper aims: This paper analyzes Command and Control (C2) Systems and identifies the level of knowledge on the subject by actors involved in disaster response operations in Brazil, besides assessing the evolution in this area since the disaster of the Serrana Region of Rio de Janeiro in 2011. Originality: The concept of C2 is still little explored academically, especially in disaster management systems. This study contributes to the understanding of the dynamics of different C2 Systems operated in Brazil, as well as identifying the level of knowledge on the subject and its evolution since 2011. Research method: This is an exploratory survey in which data was analyzed using descriptive statistics techniques. Main findings: We conclude that the actors involved in real disaster situations have little formal training in C2. The findings indicate that the performance of a simulated exercise helps in disaster preparedness, but the participants observed deficiencies concerning C2 training besides the lack of local community involvement in the simulated exercise. Implications for theory and practice: This study contributes to the disaster management literature, showing empirical evidence that the results obtained in a simulated exercise can boost the specialization of professionals in C2 systems in the area of disasters. [ABSTRACT FROM AUTHOR]

The term "commercial ornamental stones" comprises different natural stones with different mineralogical components and the distribution and amount of natural radionuclides depended on the mineralogy. Few studies on natural radioactivity in ornamental stones carried out in Rio de Janeiro (Brazil) and the present work were carried out in order to analyze the distribution of activity concentration in these materials. The activity concentration of 238U, 235U, 226Ra, 232Th and 40K in Ornamental Stone s measured using γ-ray spectrometry to estimate the radiation hazard as well as establishing a database for radioactivity levels. Samples were collected in stores in Rio de Janeiro, carefully transported, weighed, packed with PVC film and left to rest for at least 45 days to reach secular equilibrium. Samples analyzed by gamma spectrometry using a hyper pure germanium detector (HPGE). Detection efficiency for each sample was obtained using LabSOCS software. The activity concentrations for samples were within the ranges (0.83 ± 0.15 to 39.96 ± 1.19, 8.04 ± 2.54 to 111.36 ± 13.33, 0.43 ± 0.03 to 264.58 ± 0.98, BDL to 8.17 ± 0.65 and 1.30 ± 0.57 to 1567.01 ± 65.08) Bq⋅kg−1 for 238U, 226Ra, 232Th, 235U and 40K, respectively. The world average for building materials is 50 Bq⋅kg−1 for 238U, 50 Bq.kg−1 for 232Th and 500 Bq⋅kg−1 for 40K. In the present work, the average for granite was 19.43 ± 0.39 Bq⋅kg−1 for 238U, 56.70 ± 1.13 Bq⋅kg−1 for 232Th and 1113.28 ± 20.27 Bq⋅kg−1 for 40K, thus the values for 232Th and 238U are above the world average. Analyzing for the granite that showed the highest concentrations of activity the average values of Transport Rate was 3.12 ± 0.04 Bq⋅m−2⋅s−1, Emanation Rate was 0.16 ± 0.00 Bq⋅kg−1⋅s−1, Exhalation Flow was 530.26 ± 6.05 Bq⋅m−3, Effective Equivalent Dose Due to Radon Exposure was 0.78 ± 0.01 WLM⋅year−1 and Annual Effective Dose Due to Radon and Thoron was 7.02 ± 0.10 mSv⋅year−1. Annual Effective Dose Due to Radon and Thoron it is above the annual limit for public individuals which is 1 mSv⋅year−1 and below the occupationally exposed individual, which is 20 mSv⋅year−1 in an average of 5 years, it does not exceed the maximum level recommended by ICRP-60. • γ-ray spectrometry use to measure the activity concentration of natural radionuclides in ornamental stones, specifically 238U, 235U, 226Ra, 232Th, and 40K, to estimate radiation hazards and establish a database of radioactivity levels. • Focused on igneous rocks and marbles commonly used as building materials, and determined the distribution of natural radionuclide γ-ray activities as well as their transport rate, emanation rate, exhalation flow, and annual exposure to alpha energy potential Ep (effective equivalent dose) of radon and thoron. • Results showed that while all igneous rocks contained radionuclides from the uranium and thorium series as well as 40K, the annual effective dose due to airborne radioactivity did not exceed the maximum level recommended by ICRP-60. The study emphasizes the importance of environmental radiological protection in the use of building materials. [ABSTRACT FROM AUTHOR]

Infant milk is a manufactured food designed for feeding babies and infants under 12 months of age. This product is indicated when, for some reason, the baby can not be fed by breast milk. It is used in case of intolerance to milk from farmed animals and is widely used for the nutrition of newborns in artificial lactation, in place of breastfeeding. It can be used as a complete or partial substitute for human milk. In the current study, the committed effective dose and lifetime cancer risk due to ingestion of 4 K, 226Ra, and 228Ra were estimated using activity concentration obtained from high-resolution gamma spectrometry. Consumption data and dose coefficients were obtained from Brazilian Institute of Geography and Statistics and data published by ICRP 119. Infant milk and water samples were collected in the Rio de Janeiro trade, placed in a polystyrene container, and then sealed to reach the secular radioactive equilibrium condition (at least 45 days). The samples were analyzed by gamma spectrometry using a High Purity Germanium (HPGE). Detection efficiency for each sample was obtained with LabSOCS software. For infant milk samples, the highest values of activity concentrations were (242 ± 9) Bq.kg−1 for 4 K, (5 ± 1) Bq.kg−1 for 228Ra and presented values below the detection limit for 226Ra. The higher values obtained for water samples were (10 ± 1) Bq.l−1, (5 ± 1) Bq.l−1, (5.3 ± 0.1) Bq.l−1 for 4 K, 226Ra and 228Ra, respectively. These values of committed effective dose are below the values stipulated by UNSCEAR (290 μSv.y−1) and by the ICRP (1 mSv.y−1). The values obtained for lifetime cancer risk are considered negligible, once they are below the limit considered for taking action (10−4). It can be concluded that the values calculated do not present a significant risk regarding the intake of infant milk in the first two years of the child's life. • 1° estimate in Brazil of the cancer risk from the ingestion of infant formulas consumed by children using gamma spectrometry. • Activity concentrations were determined using high resolution gamma spectrometry. • Committed effective dose and the cancer risk was estimated due to the ingestion of infant milk. • Milk ingestion does not represent any significant radiological health effect. [ABSTRACT FROM AUTHOR]