Survey Meter Research Articles

241Am-Be(α,n) CHARACTERIZATION FOR A NEW LABORATORY FACILITY IN BRAZIL.

The Laboratório de Ciências Radiológicas is developing an irradiator for neutron survey meters calibration. Part of this work is related to the characterization of the neutron source that will be used in the irradiator. Therefore, a source of 241Am-Be(α,n) was characterized according to the following attributes: neutron energy distribution, anisotropy and emission rate. In order to make these values into high-level metrological references traceable by the Bureau International des Poids et Mesures, these measurements were taken at the Neutron Laboratory part of the Laboratório Nacional de Metrologia das Radiações Ionizantes. Results obtained for the source spectrum have strong adherence to the reference spectrum established by ISO 8529-1. The new laboratory for neutron calibration will allow calibration in an approximate ambient dose equivalent ranging 20-4500 μSv/h.

First demonstration of aerial gamma-ray imaging using drone for prompt radiation survey in Fukushima

Considerable amounts of radioactive substances (mainly 137Cs and 134Cs) were released into the environment after the Japanese nuclear disaster in 2011. Some restrictions on residence areas were lifted in April 2017, owing to the successive and effective decontamination operations. However, the distribution of radioactive substances in vast areas of mountain, forest and satoyama close to the city is still unknown; thus, decontamination operations in such areas are being hampered. In this paper, we report on the first aerial gamma-ray imaging of a schoolyard in Fukushima using a drone that carries a high sensitivity Compton camera. We show that the distribution of 137Cs in regions with a diameter of several tens to a hundred meters can be imaged with a typical resolution of 2–5 m within a 10–20 min flights duration. The aerial gamma-ray images taken 10 m and 20 m above the ground are qualitatively consistent with a dose map reconstructed from the ground-based measurements using a survey meter. Although further quantification is needed for the distance and air-absorption corrections to derive in situ dose map, such an aerial drone system can reduce measurement time by a factor of ten and is suitable for place where ground-based measurement are difficult.

ESTIMATION ON THE RADIOLOGICAL LEVEL OF NATURAL OCCURRING RADIONUCLIDES PRESENT IN FLOODED SOIL SAMPLES IN KADUNA NORTH, NIGERIA

The background radiation of the areas was collected at random for each point using a rados survey meter. The detectors (two rados survey meter were used) were placed 1 meter above the ground with the operator positioned a few meters away. Three (3) readings were taking from each detector in other to reduce error or reach accuracy in obtaining the background readings from each randomly selected point where soil samples were later collected.
 In the current study, the concentration levels of naturally occurring radioactive materials (NORMs) of 40K, 232Th, and 238U in the surface soil samples of selected areas in kigo road new extension Kaduna north, Kaduna in Nigeria were studied. The collected soil samples were analyzed by means of gamma-ray spectrometry. The mean activity concentrations of the natural occurring radionuclides of 226Ra, 232Th and 40K in the soil samples were estimated to be 62, 78.35, 227.17 Bq/kg respectively for kigo road new extension respectively. Radium equivalent activity, absorbed dose rate, annual effective dose equivalent were also calculated for assessment of radiological risk. External hazard value (Hex) is between 0.3163 and 0.9557 and Internal hazard value is between 0.4462 and 1.1618. The worldwide average activity concentrations of 226Ra, 232Th and 40K in soil samples from various studies around the world have values of 37, 30 and 400 Bq/kg respectively [UNSCEAR, 2000]. The values compared well with published data from UNSCEAR shows Ra-226, Th-232 from the location are well above the standards while K-40 below the risk value.

Estimation of outdoor and indoor effective dose and ex-cess lifetime cancer risk from Gamma dose rates in Gonabad, Iran

Humans' background gamma irradiation in the indoor and outdoor environments is a major concern in the world. The study area was Gonabad city. Four stations and buildings for background radiation measurement of outdoor and indoor were randomly selected and the G.M detector (X5C plus) was used. All dose rates on display of survey meter were recorded and mean of all data in each station and buildings was computed and taken as measured dose rate of that particular station. The average dose rates of background radiation were 84.2 nSv/h for outdoor and 108.6 nSv/h for indoor, maximum and minimum dose rates were 88.9 nSv/h and 77.7 nSv/h for outdoor measurements and 125.4 nSv/h and 94.1 nSv/h for indoor measurements, respectively. Results show that the annual effective dose is 0.64 mSv, which compare to global level of the annual effective dose 0.48 mSv is high. Estimated excess lifetime cancer risk was 2.24×10 -3 , indicated that it is large as compared to the world average value of 0.25×10 -3 .

The grandfather effect – Personalizing radiation safety precautions following prostate implantation with I-125 seeds

Prostate Brachytherapy with Iodine-125 seeds is considered to be on par, in terms of survival rate, with other forms of prostate cancer treatment such as EBRT and Prostatectomy. Following successful implantation patients are required to follow strict radiation protection guidelines, to ensure that exposures to family members and members of the public do not exceed specified dose limits.These guidelines include not holding a child in the lap area for more than 1 h per day and not sleeping within 1 meter of a partner. These guidelines last for a period of 1 year. Clinicians have reported that some patients may choose to refuse prostate brachytherapy as a form of treatment, because of these guidelines being too restrictive, this was seen predominately in a population of elderly gentlemen who had grandchildren. This project evaluated the dose-rates present after implantation among a population of 16 patients, by directly measuring dose-rates using a suitable survey meter. An algorithm was built to yield a theoretical estimation of these dose-rates based on the patients anatomy and seed characteristics. Using estimated and measured dose-rates it is possible to provide accurate and more flexible radiation protection guidelines to patients. Clinical tools, such as a Nomogram and Computer application, were created to allow an efficient, reproducible method allowing patients to receive radiation safety guidelines that are specific to them. It is hoped that this rigorous evaluation of current guidelines and the development of clinical tools will help to make the brachytherapy more appealing, where it is best suited. Prostate Brachytherapy with Iodine-125 seeds is considered to be on par, in terms of survival rate, with other forms of prostate cancer treatment such as EBRT and Prostatectomy. Following successful implantation patients are required to follow strict radiation protection guidelines, to ensure that exposures to family members and members of the public do not exceed specified dose limits.These guidelines include not holding a child in the lap area for more than 1 h per day and not sleeping within 1 meter of a partner. These guidelines last for a period of 1 year. Clinicians have reported that some patients may choose to refuse prostate brachytherapy as a form of treatment, because of these guidelines being too restrictive, this was seen predominately in a population of elderly gentlemen who had grandchildren. This project evaluated the dose-rates present after implantation among a population of 16 patients, by directly measuring dose-rates using a suitable survey meter. An algorithm was built to yield a theoretical estimation of these dose-rates based on the patients anatomy and seed characteristics. Using estimated and measured dose-rates it is possible to provide accurate and more flexible radiation protection guidelines to patients. Clinical tools, such as a Nomogram and Computer application, were created to allow an efficient, reproducible method allowing patients to receive radiation safety guidelines that are specific to them. It is hoped that this rigorous evaluation of current guidelines and the development of clinical tools will help to make the brachytherapy more appealing, where it is best suited.

Continuous Low-Dose-Rate Irradiation Promotes Growth of Silkworms.

To investigate the influence of low-dose-rate irradiation on the growth of silkworms, Bombyx mori, eggs of silkworms were randomly divided into 2 groups and were grown on either low-dose-radiation-emitting sheets or control sheets. On the radiation-emitting sheets, the dose rate was measured as 66.0 (4.3) μSv/h (mean [standard deviation]) by a Geiger-Müller counter for α, β, and γ rays and 3.8 (0.3) μSv/h by a survey meter for γ rays. The silkworms became larger when bred on the radiation-emitting sheets, and their body weight was about 25% to 37% heavier on day 42 to 49 after starting the experiment. Continuous low-dose-rate irradiation promoted the growth of silkworms. It should be further investigated whether this phenomenon could be utilized by the silk industry.

Gamma absorbed radiation dose in Marrah mountain series, western Sudan

Measurements of ambient gamma radiation dose and radioactivity of soil and rocks samples have been carried out in 103 sites located in the region of Marrah mountain (western Sudan) using survey meters and gamma spectrometry techniques, respectively. The ambient dose varied from 0.05 to 0.25 µSv/h with mean value of 0.18 ± 0.05 (SD) µSv/h. At high altitudes (> 1500 m), relatively high values were observed (0.18–0.22 µSv/h). The levels of 238U, 232Th and 40K in soil–rocks were in the ranges 12–80, 12–66 and 120–937 Bq/kg with mean ± SD of (41 ± 6.9), (24 ± 12) and (540 ± 99) Bq/kg, respectively, equivalent to total gamma absorbed dose of 23–142 (66 ± 20) nGy/h. The ambient dose data were presented in cartography format, and correlation to geological maps was attempted. Surface map of the absorbed dose created using geostatistical kriging tools showed the spatial distribution of dose. Analyses showed that trends of high values were located in and around areas characterized by local flow and basaltic flow lithology, while the low values were observed at locations of basement rocks (granitic) in general. That was attributed to the differences in environmental conditions in various altitude and weathering processes. The highest readings (0.25 µSv/h and 142 nGy/h) were found in Deriba Complex Pumice air-fall deposits (younger explosive phase). Health risk was assessed by calculating annual effective dose for the inhabitants resulted in values range between 0.14 and 1.4 mSv/y (mean ± SD of 0.40 ± 0.12 mSv/y). The observed values of dose rates are comparable with some countries but higher than the worldwide average for outdoor annual affective dose of 0.07 mSv/y.

CHARACTERIZATION OF CLYC SCINTILLATOR COUPLED WITH PHOTOMULTIPLIERS AND A LARGE SIPM ARRAY.

CERN Radiation Protection group has recently developed a novel radiation survey meter called B-RAD able to operate in the presence of a strong magnetic field. The B-RAD will be equipped with a series of probes for gamma dose rate, gamma spectrometry and surface contamination measurements. The feasibility of developing a probe for neutron dose rate and possibly spectral measurements is being investigated. The determination of the breakdown voltage of the SiPM as well as its uniformity between the pixels was performed. The energy resolution of the Cs2LiYCl6:Ce (CLYC) scintillator was measured with the SiPM and compared with two different PMT models: Bialkali and Superbialkali. The temperature sensitivity of the system CLYC + SiPM was measured from -10 to + 40°C.

Environmental radiation level, radiation anxiety, and psychological distress of non-evacuee residents in Fukushima five years after the Great East Japan Earthquake: Multilevel analyses

The present study aimed to clarify the associations among radiation exposure or psychological exposure to the Fukushima nuclear power plant accident (i.e., fear/anxiety immediately after the accident), current radiation anxiety, and psychological distress among non-evacuee community residents in Fukushima five years after the Great East Japan Earthquake, which occurred in March 2011. A questionnaire survey was administered to a random sample of non-evacuee community residents from 49 municipalities of Fukushima prefecture from February to April 2016, and data from 1684 respondents (34.4%) were analyzed. Environmental radiation levels at the time of the accident were ascertained from survey meter data, while environmental radiation levels at the time of the survey were ascertained from monitoring post data. In the questionnaire, immediate fear/anxiety after the accident, current radiation anxiety, and psychological distress were measured using a single-item question, a 7-item scale, and K6, respectively. Multilevel linear or logistic regression models were applied to analyze the determinants of radiation anxiety and psychological distress. The findings showed that environmental radiation levels at the time of the survey were more strongly associated with radiation anxiety than radiation levels immediately after the accident. Disaster-related experiences, such as direct damage, disaster-related family stress, and fear/anxiety after the accident, and demographic characteristics (e.g., younger age, being married, low socioeconomic status) were significantly associated with radiation anxiety. Environmental radiation levels at the time of the accident or survey were not significantly associated with psychological distress. Radiation anxiety largely mediated the association between fear/anxiety after the accident and psychological distress. In addition to environmental radiation levels, respondents’ radiation anxiety was affected by multiple factors, such as disaster-related experiences and demographic characteristics. Radiation levels were not associated with psychological distress in non-evacuee community residents. Rather, fear/anxiety after the nuclear power plant accident may be a determinant of psychological distress, mediated by radiation anxiety.

Effectiveness of a New Lead-Shielding Device and Additional Filter for Reducing Staff and Patient Radiation Exposure During Videofluoroscopic Swallowing Study Using a Human Phantom.

Interventional radiology procedures often involve lengthy exposure to fluoroscopy-derived radiation. We therefore devised a videofluoroscopic swallowing study (VFSS) procedure using a human phantom that proved to protect the patient and physician by reducing the radiation dose. We evaluated a new lead-shielding device and separately attached additional filters (1.0-, 2.0-, and 3.0-mm Al filters and a 0.5-mm Cu filter) during VFSS to reduce the patient's entrance skin dose (ESD). A monitor attached to the human phantom's neck measured the ESD. We also developed another lead shield (VFSS Shielding Box, 1.0-mm Pb equivalent) and tested its efficacy using the human phantom and an ionization chamber radiation survey meter with and without protection from scattered radiation at the physician's position on the phantom. We then measured the scattered radiation (at 90 and 150cm above the floor) after combining the filters with the VFSS Shielding Box. With the additional filters, the ESD was reduced by 15.4-55.1%. With the VFSS Shielding Box alone, the scattered radiation was reduced by about 10% compared with the dose without additional shielding. With the VFSS Shielding Box and filters combined, the scattered radiation dose was reduced by a maximum of about 44% at the physician's position. Thus, the additional lead-shielding device effectively provided protection from scattered radiation during fluoroscopy. These results indicate that the combined VFSS Shielding Box and filters can effectively reduce the physician's and patient's radiation doses.

Design and construction of portable survey meter

This work was aimed to design and construction of portable survey meter for radiation dose measuring. The designed system consists of 4 main parts consisting of low voltage power supply, radiation detection, radiation measurement and data display part on android phone. The test results show that the ripple voltage of low voltage power supply is less than 1%, the maximum integral counts are found to be 104 counts per second and the maximum distance of wireless commination between the server and the client is about 10 meter. It was found that the developed system had small size and light weight for portable instrument.

Body Surface Contamination Levels of Residents under Different Evacuation Scenarios after the Fukushima Daiichi Nuclear Power Plant Accident.

Body surface contamination levels should be correlated with inhaled actual thyroid doses during evacuation following the Fukushima Daiichi nuclear power plant (FDNPP) accident. Evacuees and residents were screened for body surface contamination using a Geiger-Mueller survey meter. The authors obtained 7,539 individual screening data sheets as well as gamma-spectrometry data from measurements made on clothing of two subjects by using a germanium spectrometer. Body surface contamination levels were analyzed in four residential groups during two different periods: 12-14 and 15-17 March 2011. Contamination levels during 12-14 March in the Tomioka/Okuma/Futaba/Naraha group were very low, indicating that residents evacuated before the radioactive plume reached their towns on 12 March. In contrast, levels in the Namie and Minamisoma groups were higher than those in the other groups in both periods, indicating that these residents were exposed to plumes twice on 12 and 15-16 March. The plume on 12 March was enriched with short-lived radionuclides: averaged proportions of radioactivity (relative to I) from Te, I, and Cs measured in clothing from two subjects were 2.3, 1.1, and 0.1, respectively, after correction for physical decay by 12:00 on 12 March. These proportions are similar to those (relative to I) from Te and Cs in dust sampled by a high-volume air sampler in the zone 20 km from the FDNPP on 12 March: 1.9 and 0.1, respectively. These data indicate that the relative contribution to inhaled thyroid dose of short-lived radionuclides in radioactive plumes released on 12 March could be as much as 37.5% in 1-y-old children.

Energy consumption in an ageing population: exploring energy use and behaviour of low-income older Australians

Abstract: This paper explores energy use and behaviour of older urban Australians by identifying the key factors that shape their energy demand. As Australia is facing an aging population, understanding what structural and behavioural factors can help improve residential energy efficiency is key for developing effective policy initiatives to support the successful management of household energy costs, wellbeing and carbon emissions within this population. This paper reports on survey and electricity meter data collected for an energy efficiency program involving 1,647 older householders (aged 60 and above) living within the Brisbane City Council Local Government Area. The program was funded by the Australian Government Low-Income Energy Efficiency Program (LIEEP) and ran from November 2013 to February 2015. Brisbane is Australia’s third largest city and has a subtropical climate, with warm or hot weather for most of the year. The findings show that electricity consumption within the study’s sample population was influenced by both structural and demographic factors. These factors include range of energy sources used, number of bedrooms and number of people living in the household, as well as type of appliances used in the home. In terms of appliance use, high-energy consuming appliances such as water heating and space cooling systems, clothes-dryers and refrigerators were important predictors of energy consumption. Over two-thirds of the study participants were relying on cooling systems for thermal comfort, and such systems were typically not being used in an energy efficient way. The use of high-energy demand heating and cooling systems can account for around 40% of energy consumption in Australian households, and has a large impact on electricity peak demand. With the penetration of air-conditioning in seniors’ home expected to increase over time, it is important to better understand the range of low and high-energy demand practices that are currently employed by older Australians to achieve thermal comfort at home. Designing strategies that minimise the need for high-energy demand cooling practices will be key for managing household energy costs and wellbeing within this target audience.

Development of lightweight portable neutron survey meter

ABSTRACTWe have developed a lightweight portable neutron survey meter comprising a proportional gas counter containing a mixed gas of methane gas and nitrogen gas for measuring the ambient neutron dose equivalent H*(10) up to about 20 MeV neutrons intended for use in nuclear power plants, and accelerator facilities. Since no heavy polyethylene moderator is used, the survey meter is only about 2.2 kg in weight causing a weight reduction of 70% or more compared to that of the conventional moderated-type survey meter. The spectrum-weight function, G(E) is adopted for dose conversion.In order to evaluate the energy characteristics of the developed survey meter, mono-energetic neutron reference fields and continuous energy neutron reference fields were used. The evaluation was also carried out by the PHITS calculation. Although the neutron energy response to the mono-energetic neutron fields was highly deviated from the ambient dose equivalent H*(10) in keV energy region, the response to H*(10) showed very good agreement only within 25% to the continuous energy neutron fields which are close to the actual work-place neutron fields. The neutron energy response was also investigated for high energy quasi-mono-energetic neutron fields and showed much better results compared with those of conventional moderated-type neutron survey meters.

Radiological assessment of the decontaminated and decommissioned Korea Research Reactor-1 building

The radiation dose of the Korea Research Reactor-1 (KRR-1), which had been decontaminated and decommissioned following shut down in 1995, was evaluated to assess the possibility of reusing the building as a memorial hall. The KRR-1 holds symbolic significance as the first reactor in Korean nuclear history and is designated as a registered cultural property of Korea. Exposure scenarios for visitors and the building manager were evaluated to examine the radiological safety of the building. Radioactive contamination inside the KRR-1 building was measured using gamma survey meter, surface alpha and beta contamination monitor, low level gas proportional counter, and semiconductor detector. The exposure dose rate for real radioactivity measurement was calculated using the RESRAD-BUILD code and uncertainty analysis was performed. The radionuclides of 60Co, 137Cs, and 152Eu were in the ranges of 0.09–0.011, 0.005–0.041, and 0.013–0.097Bq/g, respectively, on the surface of the reactor building. The external dose rate in the reactor building in the first year of the measurement ranged from 1.05×10−7 to 3.76×10−6mSv/h. The maximum exposure doses on the building manager and visitors in the first year were 1.82×10−4 and 1.07×10−6mSv/y, respectively, satisfying the dose limit for unrestricted release of the building. Thus, the radiological safety of the KRR-1 building was confirmed.

Using two detectors concurrently to monitor ambient dose equivalent rates in vehicle surveys of radiocesium contaminated land

In response to the accident at Tokyo Electric Power Company's Fukushima Dai-ichi Nuclear Power Plant (FDNPP), vehicle-borne monitoring was used to map radiation levels for radiological protection of the public. By convention measurements from vehicle-borne surveys are converted to the ambient dose equivalent rate at 1 m height in the absence of the vehicle. This allows for comparison with results from other types of survey, including surveys with hand-held or airborne instruments. To improve the accuracy of the converted results from vehicle-borne surveys, we investigated combining measurements from two detectors mounted on the vehicle at different heights above the ground. A dual-detector setup was added to a JAEA monitoring car and compared against hand-held survey meter measurements in Fukushima Prefecture. The results obtained by combining measurements from two detectors were within ±20% of the hand-held reference measurements. The mean absolute percentage deviation from the reference measurements was 7.2%. The combined results from the two detectors were more accurate than those from either the roof-mounted detector, or the detector inside the vehicle, taken alone. One issue with vehicle-borne surveys is that ambient dose equivalent rates above roads are not necessarily representative of adjacent areas. This is because radiocesium is often deficient on asphalt surfaces, as it is easily scrubbed off by rain, wind and vehicle tires. To tackle this issue, we investigated mounting heights for vehicle-borne detectors using Monte Carlo gamma-ray simulations. When radiocesium is deficient on a road compared to the adjacent land, mounting detectors high on vehicles yields results closer to the values adjacent to the road. The ratio of ambient dose equivalent rates reported by detectors mounted at different heights in a dual-detector setup indicates whether radiocesium is deficient on the road compared to the adjacent land.

Assessment of medical radiation exposure to patients and ambient doses in several diagnostic radiology departments

In many countries diagnostic medical exposures typically account for a very large fraction of the collective effective dose that can be assigned to anthropological sources and activities. This in part flags up the question of whether sufficient steps are being taken in regard to potential dose saving from such medical services. As a first step, one needs to survey doses to compare against those of best practice. The present study has sought evaluation of the radiation protection status and patient doses for certain key radiological procedures in four film-based radiology departments within Sudan. The radiation exposure survey, carried out using a survey meter and quality control test tools, involved a total of 299 patients their examinations being carried out at one or other of these four departments. The entrance surface air kerma (ESAK) was determined from exposure settings using DosCal software and an Unfors -Xi-meter. The mean ESAK for x-ray examination of the chest was 0.30±0.1mGy, for the skull it was 0.96±0.7mGy, for the abdomen 0.85±0.01mGy, for spinal procedures 1.30±0.6mGy and for procedures involving the limbs it was 0.43±0.3mGy. Ambient dose-rates in the reception area, at the closed door of the x-ray room, recorded instantaneous values of up to 100 µSv/h. In regard to protection, the associated levels were found to be acceptable in three of the four departments, corrective action being required for one department, regular quality control also being recommended.

Indeks massa tubuh dan kejadian diabetes melitus pada penduduk dewasa di Indonesia: analisis data IFLS tahun 2015

Body mass index and incidence of diabetes mellitus in adult population in Indonesia: analysis of IFLS data 5PurposeThis study aimed to determine the relationship between BMI with DM incidence in the adult population in Indonesia.MethodsThis cross sectional study was conducted using the 5th Indonesian Family Life Survey (IFLS5) data which is a collaboration of the RAND corporation and Survey Meter. Chi square and logistic regression tests were used to analyze the relationship between BMI and DM incidence. BMI was obtained through measurement of body weight and height in respondents aged > 18 years. Information on the incidence of DM was obtained from interviews with respondents.ResultsThere were 22,647 subjects who met the study criteria. The proportion of DM in this study was 2.89%. People with obese BMI had a higher risk of developing DM than people with underweight BMI (OR = 3.15; 95% CI = 2.05- 4.82). After adjusting for gender, age, and education variables, the risk remained significant (OR = 3.29; 95% CI = 2.14-5.065).ConclusionBody mass index is associated with the incidence of diabetes mellitus, in which people with excessive BMI or obese have a greater risk of developing DM than people with underweight BMI.

Assessment of natural radioactivity and gamma-ray dose in monazite rich black Sand Beach of Penang Island, Malaysia

Activity concentrations of primordial radionuclides in sand samples collected from the coastal beaches surrounding Penang Island have been measured using conventional γ-ray spectrometry, while in-situ γ-ray doses have been measured through use of a portable radiation survey meter. The mean activity concentrations for 226Ra, 232Th and 40K at different locations were found to be less than the world average values, while the Miami Bay values for 226Ra and 232Th were found to be greater, at 1023±47 and 2086±96Bqkg̶ 1 respectively. The main contributor to radionuclide enrichment in Miami Bay is the presence of monazite-rich black sands. The measured data were compared against literature values and also recommended limits set by the relevant international bodies. With the exception of Miami Bay, considered an elevated background radiation area that would benefit from regular monitoring, Penang island beach sands typically pose no significant radiological risk to the local populace and tourists visiting the leisure beaches.

Mapping of natural gamma radiation (NGR) dose rate distribution in tin mining areas of Jos Plateau, Nigeria

An extensive study was conducted to measure the natural gamma radiation (NGR) dose rates for the tin mining areas of Jos Plateau with an objective to establish a reference data record on the levels and distribution of natural background gamma radiation. The measurement was carried out using a portable NaI(Tl) scintillation survey meter. The results obtained, varied significantly for different soil types and for geological features of the study area. NGR dose rates values ranged between 40 nGy h−1 measured on Ferric Luvisols–Ferric Luvisols (S13) soil type, underlain by geological formation G7 (sandstone, clay and shale) and 1265 nGy h−1 recorded on, Haplic Acrisols (S27), underlain by geological formation G8 (Younger granites) with overall mean value of 250 nGy h−1. This is by a factor of four higher than the reported world average value of 59 nGy h−1. Mean indoor and outdoor annual effective dose for the public was estimated to be 1.2 and 0.31 mSv/y, respectively. An isodose map for the distribution and exposure rate due to natural sources radiation for the study area was also plotted using ArcGis software. The data here presented can use to prepare a national radiological map for the country.