Outdoor Gamma Dose Rates Research Articles

Terrestrial gamma radiation dose (TGRD) rates and radiological risk assessments in Tiru region of the Naga Schuppen Belt, India

The aim of the present study is to assess the levels of dose rates and the potential risks of exposure to terrestrial gamma radiations in indoors and outdoors in houses in Tiru coal mining area. A highly sensitive portable micro-R gamma survey metre incorporated with a NaI (Tl) scintillator has been used for this study. Indoor and outdoor gamma dose rates (GDRs) have been estimated to be 58.5-178.3 nGy h-1 and 55.5-81.9 nGy h-1, respectively, with averages of 89.7 7.4 nGy h-1 and 65.7 5.8 nGy h-1, considerably higher than the reported global population-weighted averages. The annual effective doses (AEDs) for indoors and outdoors have been estimated to be in the ranges of 0.29-0.87 mSv y-1 and 0.07-0.1 mSv y-1, with averages of 0.44 0.04 mSv y-1 and 0.08 0.01 mSv y-1, which are marginally higher than the reported global averages. The excess lifetime cancer risk (ELCR) has been calculated and found to be in the range of 1.2 10-3-3.4 10-3 with an average of 1.8 10-3. This study contributes significantly to the scientific understanding of radiation exposure in an open-cast coal mining area as well as its potential impact on human health.

Poziomy zewnętrznych dawek promieniowania gamma w wybranych miejscach w Rumunii, Mołdawii i Grecji

The study presents a synthesis of results obtained in the frame of international cross-border projects, implemented in partnership, for gamma radiation dose rates measured in outdoor environments in various sites in Romania, Moldova, Greece, including urban, rural, touristic and protection areas. The selected sites (n=41) are found in the Eastern Carpathians Mountains, Lower Danube basin, Danube Delta, Lower Prut River Reserve, Dniester River, as well as Black Sea and Northern Aegean Sea basins. The data recorded for targeted spots using portable dosimeters highlight an hourly and daily variation of the outdoor gamma dose rate and the specificity of the geological background and terrain utilization. The mean values of outdoor gamma radiation dose rate, calculated for 50 measurements per each site, are ranging between 71 nGy/h (Vama Veche, Constanta County, Black Sea coast, Romania) and 394 nGy/h (Nea Peramos, Ammolofoi beach, Northern Aegean Sea, Greece), with a minimum of 41 nGy/h in Vama Veche and a maximum of 489 nGy/h in Ammolofoi beach. A comparison is made with legislated values and other world places. The measurements performed at water surface during boat expeditions (n=21) on Danube River and Danube Delta lakes and channels point out lower values of dose rate, due to the weak influence of gamma rays’ emission from bottom sediments. The data of the dose rate temporal variations will be used for the target regions as a base in further investigations and preparation of maps of gamma dose rates (terrestrial and cosmic), and calculation of the health risk for inhabitants and tourists.

A large and feasible national survey representative of population exposure to outdoor gamma radiation in urban areas.

Although data on outdoor gamma radiation are available for many countries, they have generally been obtained with measurements performed in undisturbed environments instead of in urban areas where most of the population lives. Only one large national survey, with on-site measurements in urban areas, has been identified worldwide, probably due to high costs (e.g., personnel and instrumentation) and difficulties in selecting measuring points. A campaign of outdoor gamma radiation measurements has been carried out in the entire Italian territory. All measurement points were selected at the infrastructures of an Italian telecommunications company as representatives of all the possible situations of outdoor exposure to gamma radiation for population in urban areas. Ten replicates of portable gamma (X) detectors carried out all the measurements. Approximately 4,000 measurements have been performed. They are distributed across 2,901 Italian municipalities, accounting for 75% of the Italian population. The national population-weighted mean of the gamma ambient dose equivalent rate (ADER) is 117 nSv h-1, and it ranges from 62 to 208 nSv h-1 and from 40 to 227 nSv h-1 for 21 regions and 107 provinces, respectively. The average variability at the municipal level, in terms of the coefficient of variation (CV) is 21%, ranging from 3 to 84%. The impact of land coverage and the distance from a building on the outdoor gamma radiation level was assessed with complementary measurements, leading to differences ranging from -40 to 50% and to 50%, respectively. A representative campaign of outdoor gamma dose rate measurements has been performed in Italy, only in urban areas, to assess the exposure effect due to outdoor gamma radiation on the population. It is the largest national campaign in urban areas worldwide, with a total of 3,876 on-site measurements. The land coverage and the distance from surrounding buildings were recognized to strongly affect outdoor gamma radiation levels, leading to high variability within small areas. The collaboration with a company that owns a network of facilities on a national territory as dense as the residing population made this survey feasible and affordable. Other countries might adopt this methodology to conduct national surveys in urban environments.

Spatial Distribution of Gamma Dose Rates and Radioactivity Levels in Some Parts of Iju Community in Ado-Odo Ota, Ogun State

This study investigates the background dose rates and radiological risk exposure to Iju community in Ado-Odo Ota. Using a hand-held calibrated gamma detector (RS-125 Gamma-Spec), the study area’s outdoor gamma dose rates and radionuclide activity concentrations of 40K, 238-U, and 32-Th were measured in situ. The results showed differing activities of the primordial radionuclides (40-K, 238-U, and 232-Th) with average values lying within the recommended limits, with the exception of 40K, which geologically can be caused by regional subsidence while on marine transgression. Based on statistical analysis, the correlation results verified that 40K, 238-U, and 232-Th were the primary causes of the elevated outdoor dose rates at Iju community. The International Commission on Radiological Protection (ICRP) specified allowable limits for radiation exposure, and the estimated mean hazard indices for the increased lifetime cancer risk in the research area exceeded these limitations. In order to ensure sufficient radiation protection, the research area needs attention right away.

Hazard assessment of outdoor gamma radiation in Tavsanli, Kutahya region of Turkiye

In the present study, outdoor gamma dose rates have been measured by using a NaI(Tl) scintillation detector in 20 measurement points in the Tavsanly district center of Kutahya province in Turkiye. Annual effective dose equivalents and lifetime cancer risks have been calculated from the obtained results as (106.64 ?6.20) ?Sv and (3.73 ?0.2) ?10-4, respectively. The results have been compared with those of other studies for Turkiye and the world literature

Radiological risk estimation from the terrestrial gamma dose rate in the seismically active Kopili Fault Zone, India

ABSTRACT Anomalies in terrestrial gamma radiation have been reported in regions of seismic activity. The Kopili Fault in India is well-known for being extremely seismically active. Several mild to moderate-magnitude earthquakes with epicentres along the Kopili Fault Zone have recently been recorded. This necessitates a measurement of variations in gamma radiation and its associated radiological risks to the population in the region in relation to seismic activities. In this work, a portable gamma survey metre was used to measure terrestrial gamma radiations in the earthquake-prone Dhekiajuli area of Sonitpur district, India, which is located in the Kopili Fault Zone. Indoor and outdoor gamma dose rates were found to be 99.4 ± 5.1–195.9 ± 5.1 nGy h−1 (geometric mean: 159.0 ± 8.8 nGy h−1) and 99.4 ± 5.1–198.8 ± 5.1 nGy h−1 (geometric mean: 132 ± 6.5 nGy h−1), respectively. The estimated total annual effective dose equivalents (geometric mean: 0.94 ± 0.05 mSv y−1) were found to be higher than the recommended global average of 0.48 mSv y−1. The excess lifetime cancer risk was also estimated by considering the life span of an individual as 70 years, which ranged from 2.4 × 10−3 to 4.8 × 10−3.

Public Exposure to Natural Radiation and the Associated Increased Risk of Lung Cancer in the Betare-Oya Gold Mining Areas, Eastern Cameroon

Background: This study aims to reevaluate natural radiation exposure, following up on our previous study conducted in 2019, and to assess the associated risk of lung cancer to the public residing in the gold mining areas of Betare-Oya, east Cameroon, and its vicinity.Materials and Methods: Gamma-ray spectra collected using a 7.62 cm×7.62 cm in NaI(Tl) scintillation spectrometer during a car-borne survey, <i>in situ</i> measurements and laboratory measurements performed in previous studies were used to determine the outdoor absorbed dose rate in air to evaluate the annual external dose inhaled by the public. For determining internal exposure, radon gas concentrations were measured and used to estimate the inhalation dose while considering the inhalation of radon and its decay products.Results and Discussion: The mean value of the laboratory-measured outdoor gamma dose rate was 47 nGy/hr, which agrees with our previous results (44 nGy/hr) recorded through direct measurements (in situ and car-borne survey). The resulting annual external dose (0.29±0.09 mSv/yr) obtained is similar to that of the previous study (0.33±0.03 mSv/yr). The total inhalation dose resulting from radon isotopes and their decay products ranged between 1.96 and 9.63 mSv/yr with an arithmetic mean of 3.95±1.65 mSv/yr. The resulting excess lung cancer risk was estimated; it ranged from 62 to 216 excess deaths per million persons per year (MPY), 81 to 243 excess deaths per MPY, or 135 excess deaths per MPY, based on whether risk factors reported by the U.S. Environmental Protection Agency, United Nations Scientific Committee on the effects of Atomic Radiation, or International Commission on Radiological Protection were used, respectively. These values are more than double the world average values reported by the same agencies.Conclusion: There is an elevated level of risk of lung cancer from indoor radon in locations close to the Betare-Oya gold mining region in east Cameroon. Therefore, educating the public on the harmful effects of radon exposure and considering some remedial actions for protection against radon and its progenies is necessary.

Dispersion of gamma dose rates and natural radionuclides in the coastal environments of the Unumherin community in Niger Delta

The outdoor gamma dose rates and the activity concentrations of potassium-40, uranium-238, and thorium-232 within the study area were carried out using calibrated hand-held gamma detector (RS-125 gamma spectrometer) and NaI(Tl) gamma spectroscopy. The in-situ measurement results of the gamma dose rate indicate that the hotspot is at location 4 with a value of 100 nGyh-1. The results from the NaI(Tl) gamma detector revealed the highest activity concentrations of potassium-40, uranium-238, and thorium-232 to be 288.09, 96.49, and 136.12 Bqkg−1 for sediments and 257.31, 66.93, and 96.57 Bqkg for water, respectively. The highest mean activity concentration of potassium-40 and uranium-238 was observed in Catfish with values of 151.87 and 38.00 Bqkg−1, whereas the highest value for the activity of thorium-232 was observed in Tilo Fish with a value of 89.02 Bqkg-1. In comparison, all the observed values are higher than the population-weighted average of 420.00, 32.00, and 45.00 Bqkg−1 for potassium-40, uranium-238, and thorium-232 according to UNSCEAR. Geologically, this may be attributed to the marine incursion of regional tectonic subsidence during transgression. Statistically, the correlation results confirmed that the enhanced outdoor dose rates at the coastline environment were caused mainly by uranium-238, followed by thorium-232 and then potassium-40 in magnitude. The mean hazard indices calculated for the samples were also observed to be within the global average values recommended by ICRP.

Measurements of Terrestrial Gamma Dose Rate Distributions along Idiroko Road, Ota, Ogun State, Nigeria: Health Implications on Roadside Dwellers

An extensive study concerning the terrestrial gamma dose rates of the surface soils from Canaanland entrance Road, Ota to Eleha Complex along Idiroko Road, Ota has been carried out to cover the road running across both areas. The In-situ measurements of gamma dose rates and radionuclides were carried out using the Gamma detector (Super Spec RS 125). The result shows that the average outdoor gamma dose rate in the study area is 73.57 nGyh−1. The average values of the radionuclides obtained were 32.9 Bq/kg for 238U, 68.4 Bq/kg for 232Th, and 328.7 Bq/kg for 40K. The background dose rate of 113.3 nGy/h was found in station 9 and is twice higher than the recommended permissible limit of 59 nGy/h suggested by UNCSEAR, 2000, and ICRP, 1999, respectively. Results were obtained based on radiological parameters for the outdoor absorbed dose rate (Dout) with a mean value of 73.57 nGyh−1, the indoor absorbed dose rate (Din) with a mean value of 131.84 nGyh−1, the annual effective dose rate (AEDR) with a mean value of 0.74, the radium equivalent (Raeq) with a mean value of 156.0, the internal hazard index (Hin) with a mean value of 0.51, the external hazard index (Hex) with a mean value of 0.42 and the excess lifetime cancer risk (ELCR) with a mean value of 2.57. Similarly, results obtained from estimated radiological parameters show that the station with the highest value for radium equivalent (Raeq), external hazard index (Hex), internal hazard index (Hin), and annual effective dose rate (AEDR) is Station 9 at 237.91 Bq/Kg, 0.64, 0.72 and 1.13 mSvy−1 respectively while the station with the lowest value for radium equivalent (Raeq), external hazard index (Hex), internal hazard index (Hin) and annual effective dose rate (AEDR) is Station 17 at 85.58 Bq/Kg, 0.23, 0.27 and 0.40 mSvy−1 respectively. This study will serve as a guide on assessing the road construction materials on radioactive contents before application to reduce the exposure risks to the populace along the busy roadsides.

Gamma radiation dose rate distribution in the Anand, Bharuch, Vadodara, and Narmada districts of Gujarat, India.

Radiation is present everywhere in the earth, and human beings are continuously exposed to gamma radiation. The health consequences of environmental radiation exposure are a serious societal issue. The purpose of this study was to analyse outdoor radiation in four districts of Gujarat, India: Anand, Bharuch, Narmada, and Vadodara duringsummer and winter seasons. This study illustrated the influence of lithology of areas on gamma radiation dose values. Summer and winter seasons are the primary factors that alter the causes directly or indirectly; therefore, the influence of season fluctuation on radiation dose rate was investigated. The annual dose rate and mean gamma radiation dose rate values from four districts were found to be greater than the global population weight average value. The mean value of gamma radiation dose rate from 439 locations in thesummer and winterseasons was 136.23 nSv/h and 141.58 nSv/h, respectively. According to a paired differences sample study, the significance value between outdoor gamma dose rate insummer and winterseasons was 0.05 indicating that seasons have a significant impact on gamma radiation dose rate. The impact of various types of lithology on gamma radiation dose was studied in all 439 places, and the statistical analysis revealed that there was no significant association between lithology and gamma radiation dose rate in the summer season, but a relationship between lithology and gamma dose rate was observed in the winter season.

Variation of annual indoor and outdoor gamma dose rate in the lower Himalayan region of Reasi district of Jammu and Kashmir, India

The exposure from natural sources of radiation imparts a major contribution to doses, both due to external and internal exposures that would be received by members of public, and its levels rely upon the lithology, altitude, and building construction materials. The measurement results of ambient indoor and outdoor radiation levels at 28 locations (villages) of Reasi district, Jammu and Kashmir, India, are presented. The ambient radiation levels were measured utilizing a portable gamma survey meter. For the outdoor environment, the minimum and maximum gamma dose rates were 0.09 and 0.29 μSv/h, whereas, at indoors, the minimum and maximum gamma dose rates were 0.08 and 0.22 μSv/h, respectively. Impact of elevation (height above sea level) on radiation levels has been investigated, and it revealed a weak positive relationship with altitude. Effects of lithology on indoor and outdoor gamma dose rates have likewise been investigated. The average annual effective dose value due to ambient radiation levels was well within the world average values.

Study of certain congenital malformations due to low-level radiation exposures from high background radiation areas

The coastal regions of some states (Kerala, Tamil Nadu, Andhra Pradesh and Orissa) in India are known to have plenty of thorium-rich minerals, therefore possess high external gamma radiation fields, and are identified as Natural High Background Radiation Areas. There are concerns about congenital malformations due to the high background radiation prevailing in the region.Therefore, scientists find interest to study the possible biological effects of low-level exposures on the local populace who are living with generations under these extraordinary radiation fields. The present study is an attempt to find the correlation between the incidences of certain congenital malformations through a 1:3 matched case-control study. A total of 75 subjects (58 mental retardation cases and 17 Cleft lip/palate cases) along with 225 controls were selected for the investigations. Indoor and outdoor gamma dose rates were measured using a halogen-quenched GM tube-based survey meter, while the indoor inhalation dose rates were measured based on the radon and progeny measurements using the twin cup dosimeters equipped with LR-115 Type II solid-state nuclear track detectors. Conditional logistic regression analysis was used to find out the correlation between the radiation dose with congenital malformation. This study found an insignificant risk of cleft lip/palate (but not for mental retardation) from the exposures to natural high external gamma radiation fields in the study area. Therefore, the results of the investigation indicate no explicit risk of congenital malformations by the high background natural radiation prevailing in the region.

Spatial interpretation, radiological mapping of background gamma radiation and risk evaluation for Southern regions of Tamil Nadu, India

The outdoor gamma dose rate was measured in 540 locations in southern regions (Ramanathapuram, Virudhunagar, Tirunelveli, and Thoothukudi) of Tamil Nadu, India. The measured dose rates vary from 35 to 335 nSv/h (mean 89 nSv/h). The observed mean dose rate (89 nSv/h) is 2.3 times higher than the national (India) average of 39 nSv/h (56 nGy/h) and 2.1 times higher than the world average of 41 nSv/h (59 nGy/h). Annual Effective Dose (AED) calculated varies from 0.04 to 0.41 mSv/y (mean 0.11 mSv/y). The mean AED (0.11 mSv/y) is 1.6 times higher than the world average annual effective dose of 0.07 mSv/y. 30% of the locations have higher AED values due to the higher radiation in that locations. The present study reveals that the Tirunelveli district of the southern Tamilnadu region has higher gamma radiation than the other four districts of this region and is due to the topography of coastal and mountainous areas in Tirunelveli. The higher gamma radiation dose in the study area is due to the radionuclides present in the mountainous region's rocks and the coastal regions' soils. The radiological maps were used for spatial interpretation of the outdoor gamma dose rate in the study area. The radiological cancer risk assessment reveals that the Tirunelveli district has a higher risk due to the higher background gamma radiation.

A Thoron Anomaly in the Soil Gas: A Case Study From Büyükorhan, Bursa, Turkey

The main sources of radiation exposure are the inhalation of radon, thoron and their decay products released from the rocks and soil, and terrestrial gamma radiation. In order to estimate the potential effects, the radon and thoron concentrations in the soil gas, the radon measurements in the groundwaters and outdoor gamma dose rates were measured at 18 different locations in Büyükorhan in the south of Bursa, which granitoid unit takes up a vast space in this area. The radon and thoron concentrations in the soil gas were found to vary from 0.54 ± 0.01 kBq m−3 to 36.25 ± 0.98 kBq m−3 (mean value 11.54 ± 2.79 kBq m−3) and from 14.86 ± 1.21 kBq m−3 to 1462.50 ± 26.47 kBq m−3 (mean value 174.53 ± 87.35 kBq m−3), respectively. The measured radon concentrations in the groundwater samples ranged from 6.89 ± 1.11 to 61.43 ± 0.55 Bq l-1 (mean value 24.85 ± 4.36 Bq l-1). The measured outdoor gamma dose rates varied from 68 nGy h-1 to 369 nGy h-1 (mean value 129.7 nGy h-1). It was observed that radon and thoron concentrations in the soil gas are controlled by the lithology of the region. Additionally, the effect of the radon and thoron concentration in soil gas on outdoor gamma dose rate is indicated in the present study.

SAFETY ASSESSMENTS FOR SUPPORTING THE APPLICATION OF NUCLEAR TECHNOLOGY IN INDONESIA AND A COMPREHENSIVE STUDY ON HIGH NATURAL RADIOACTIVITY AREA

SAFETY ASSESSMENTS FOR SUPPORTING THE APPLICATION OF NUCLEAR TECHNOLOGY IN INDONESIA AND A COMPREHENSIVE STUDY ON HIGH NATURAL RADIOACTIVITY AREA. Historically BATAN was established to investigate the negative impacts of nuclear explosions previously conducted in the Pacific area. However, this governmental institute is presently tasked to carry out research and development as well as services in the field of radiation safety and metrology. Therefore, this study aim to determine the activities carried out by BATAN in assessing the safety of workers and the environment. For instance, a standard source of dosimetry laboratory (SSDL) is used in calibration services to successfully support radiotherapy, with the highest achievement in the Designated Institute (DI) for Ionizing Radiation. The health research covers the application of gamma rays to create malaria vaccine, diagnose metabolic diseases with nuclear medicine techniques, and microdosimetry through radiodiagnostic assessment. This study also determined the effective dose and epidemiological study of radioecology and radiation biology in Mamuju (HBRA), which provides a unique opportunity to examine the health effects of chronic low-level radiation exposure to humans. Furthermore, the authors collaborated with Hirosaki University to obtain valuable information on the essential need to assess the health and physical status as well as cytogenetic and deoxynucleotide acid (DNA) damages in the lymphocytes of local populations. Dosimetry study was conducted by direct measurement in the field area by analyzing external radiation exposure of indoor and outdoor gamma dose rate. The internal radiation assessment was conducted by taking urine and inhaled air (radon) from the residents. Studies through the cytogenetic response supported by γ-H2AX, G0, and G2 micronucleus assays and TP53 showed no impacts on the natural radiation with significant differences compared to the control. Marine radioecology studies and radionuclides monitoring throughout the Indonesian archipelago showed no negative impacts as well. Nuclear emergency practice needs to be routinely conducted in the Center for strengthening safety and security cultures.

Exposed Gamma Doses in air and Assessment of Cancer Risk around Gebze (Kocaeli/Turkey) Region

By this study, it is focused to assessment of inhalation quality for Kocaeli province especially Northeast side of Marmara Sea (Gebze county and its territory). In this case, radioactivity analysis in air was realized via air dose rate measurements around this region which is so closed neighbor to big city Istanbul. By measuring of the outdoor gamma dose rates on 35 stations, it was possible to get the average dose rate. Then it was calculated to annual dose in air. Besides, cancer risk was determined for Kocaeli. All these values were compared with the World’s references (UNSCEAR) and reported finally. It was measured the average dose rate as 23.90 nGyhr-1 and annual dose was calculated to 29.31 μSv. This dose is required to excess lifetime cancer risk as 1.02x10−4. These values could be compared to the similar studies which existed around the world. Finally, the average annual effective dose equivalent and excess lifetime cancer risk for Kocaeli, are less than the world average. This study would be used to a reference for further investigations, besides it will be usefull to compare with different studies for Kocaeli which, will be evaluated in the future, for example after a nuclear pollution, such as based on a reactor leakage comes from Black Sea region and neighbours, nuclear attacks, etc., too. Another benefit would be made to enlarge to find this kind of studies in literature.

Statistical Study of the Factors Affecting Outdoor Gamma Dose Rate and Impact of Season

ABSTRACT The objective of the study was to find the significant impact of season on the outdoor gamma dose rate including statistical analysis. Outdoor gamma dose rates were studied for 52 locations of the Balod district, Chhattisgarh, India, in summer and winter. Statistical analysis confirmed that there was no significant difference in dose rate between summer and winter. Geology of the area was the most important factor, and meteorological parameters had less influence; consequently, in this investigation, the impact of these parameters were checked through linear regression, cluster, principal component and factor analysis.

Impact of lockdown during COVID-19 pandemic on annual effective dose equivalent values of natural gamma radiation.

The study aimed to determine the impact of COVID-19 on values of annual effective dose equivalent of the natural gamma dose rate of Balod, Durg and Bemetara districts of Chhattisgarh (India). COVID-19 is a severe problem for many countries and to control and prevent the spread of this problem, the lockdown approach has been implemented in many countries, including India. In this lockdown situation, almost all people stay at home for 24 h. Due to the present status of COVID-19, the Indian government also fixed the 67 days lockdown and one day was already successfully done as Janta Curfew, which worked the same as a lockdown. The value of indoor gamma dose rates was reported to be higher in most places compared to the outdoor gamma dose rate, but in this pandemic situation, occupancy factor values are not applicable as recommended by UNSCEAR for calculation of annual effective dose equivalent (AEDE). Therefore, the present study introduces the new equations, which can measure the extra AEDE value during lockdown for adults, children and infants.

Spatial distribution of natural and artificial radioactivity concentrations in soil samples and statistical approach, Nevşehir, Turkey

Abstract The concentrations of 226Ra, 232Th, 40K and 137Cs radionuclides in soil samples collected from 323 different regions of Nevşehir province were determined by using a gamma spectrometer with an HPGe detector. The mean gamma activity concentrations (ranges) of 226Ra, 232Th, 40K and 137Cs for districts were determined as 49.45 (7.40–193.90), 54.08 (<2.8–122.50), 698.43 (37.67–1370.20) and 8.26 (0.10–52.60) Bq kg−1, respectively. The mean activity concentrations of 226Ra, 232Th and 40K were higher than the world mean value. According to Kolmogorov–Smirnov test, distributions of 226Ra, 232Th and 137Cs show log-normal distributions. Whereas, 40K shows normal distribution. The mean radium equivalent activity was 181.68 Bq kg−1 which is lower than the recommended maximum value of 370 Bq kg−1. The mean external terrestrial gamma dose rate was found to be 85.12 nGy h−1. The calculated external hazard value was 0.49 and within the acceptable limit which is less than unity (Hex ≤ 1). Thermo Scientific RadEye NBR detector was used to determine environmental gamma dose rates. The gamma dose rates were measured at 445 points at a height of 1 m from land surface. The mean outdoor gamma dose rate (range) was found as 150.13 (50–480) nGy h−1. This mean value was found higher than world mean value. The fact that most of the Nevşehir province is based on volcanic rocks explains why the gamma dose rates are high.

Variation in value of annual effective natural gamma dose rate during lockdown in the pandemic situation in various countries

ABSTRACT Coronavirus Disease 2019 (COVID-19) has been declared officially as the pandemic worldwide. This novel coronavirus affects almost the whole world and it can quickly spread among the population in several ways. This has initially come from China and within a few months, covers the overall world. Therefore, many countries have decided to restrict the movement through lockdown to control the spreading of COVID-19 novel virus among the population. During this lockdown condition, almost all except few essential people stay at home means staying inside of houses 24 × 7 hours. The study aims to calculate the impact of this lockdown condition on the annual natural gamma radiation dose. The values of indoor gamma radiation are not the same as the outdoor gamma dose rate; the ration between indoor and outdoor gamma dose rates varies based on country to country. In this study, we have used indoor-outdoor gamma dose rate ratio which was reported by UNSCEAR (United Nations Scientific Commission on Effects of Atomic Radiation) and calculated the variation of annual dose rate during this pandemic condition that will be helpful for estimation of gamma expose scale for this year of various countries. The higher ratio of indoor and outdoor gamma dose rates showed a high variation in annual dose rate. It was found that the change in annual dose rate continuously increases with respect to the number of days of lockdown. This will also affect much more at high background radiation areas as compared to the low background area.