Qassim area soil. The results in the present work indicate that the area under investigation has different Radonconcentrations according to depth from the ground sur- face and the locations of the sample point. The concen- tration increases with depth from the ground surface. The results, in average, are less than the reported average in Kurdistan Iraq or in Jordan. The continuous monitoring, Alpha GUARD 2000 PRQ probes, are a simpler and fast method of measuring the Radon gas concentration in soil. This kind of measurements, together with permeability of soil, can be helpful in complying new radiation pro- tection regulation to estimate health hazard index due to radiation exposure in Saudi Arabia.
For outdoor radonconcentrations, short-term measurements based on active method were performed using continuous radon progeny monitors model DosemanPro (Sarad, Germany). The monitors were calibrated by the manufacturer. The monitor is equipped with alpha spectroscopy system which capable of discriminating alpha energy peaks emitted by radon/thoron progenies. The equipment consists of a membrane pump, a USB interface, a semiconductor detector, a filter paper holder and a rechargeable battery. The sampling of radon progenies was performed by pumping the air through the filter paper. The monitor was placed on a tripod stand at a height of 1 m above the ground. As far as possible, the measurement was conducted for a period of about 24 hours in order to obtain a representative average radon concentration for one day. The advantage of using this type of equipment can record radonconcentrations variation against time of the day. The radonconcentrations are normally high or maximum in the early morning and low or minimum in the afternoon. The radon progenies concentrations in term of Equilibrium Equivalent Concentration (EEC) in Bqm -3 were then converted to radon gas concentration using appropriate equilibrium factor (UNSCEAR, 2000). Whilst in Ranau, due to logistic problems, the measurements for both indoor and outdoor radonconcentrations were performed based on active method using the same type of equipment used in Cameron Highlands. For indoor measurement, the monitor was normally placed on a table or cupboard at least 30 cm from the wall.
Abstract. This paper presents results of a reconnaissance study that used CR-39 alpha track-etch detectors to mea- sure radonconcentrations in dwellings in Hamadan, western Iran, significantly, built on permeable alluvial fan deposits. The indoor radon levels recorded varied from 4 (i.e. below the lower limit of detection for the method) to 364 Bq/m 3 with a mean value of 108 Bq/m 3 which is 2.5 times the aver- age global population-weighted indoor radon concentration – these data augment the very few published studies on indoor radon levels in Iran. The maximum radon concentration in Hamadan occurs during the winter period (January to March) with lower concentrations during the autumn. The effective dose equivalent to the population in Hamadan is estimated from this study to be in the region of 2.7 mSv/y, which is above the guidelines for dose to a member of the public of 1 mSv/y suggested by the International Commission on Ra- diological Protection (ICRP) in 1993. This study supports other work in a number of countries that indicates such per- meable “surficial” deposits as being of intermediate to high radon potential. In western Iran, the presence of hammered clay floors, the widespread presence of excavated qanats, the textural properties of surficial deposits and human behaviour intended to cope with winds are likely to be important factors influencing radonconcentrations in older buildings.
Selvasekara pandian S. (2001) focused on the radon concentration in water in Coonoor, India. The gas collection measurement method was employed to determine radon activity concentrations in the water of Coonoor. Open well water, dam water and stream water have been investigated for their radonconcentrations. It is observed from the table that the 222 Rn concentration varies from 0.03 Bq l -1 to 5.72 Bq l -1 with a mean value of 1.20 Bq l -1 . The calculated annual average effective dose for the stomach is 6.9 µSv y -
Radon indoor concentrations and its relation with lung cancer has been an unknown problem for a long time. At present, because of the governmental agencies normatives, it has a place on public health agendas. There are several factors that influences in this problem, being the atmospheric pressure, the type of con- struction and, mainly, the geological substrate part of these factors. The target of the current work is estab- lishing the relation of the harmful radonconcentrations with the geologic substrate in the Northwest of the Iberian Peninsula. To achieve this, the Galicia Radon Laboratory (RADONGAL) has more than 4,000 meas- urements over one of the regions of the Northwest of the Iberian Peninsula, Galicia, which, combined with the geological shapefile can determinate, in an approximate way, this relation. Two cases with different geological setups, and different concentration values range, has been analysed to determinate which mate- rials present the higher radonconcentrations in the territory and which are the radon-prone areas where a priority actuation is required.
In Saudi Arabia radonconcentrations have been considered by the scientists as well and measured in several parts in the Kingdom.  published radon measurements in a total of 19 Khafji cities and discuss the first sur- vey of this type in Saudi Arabia.  monitored radon in 1200 houses in four cities Hafr Al-Batin, Khafji, Madina and Taif.  monitored radon in 2700 house and 98 school nine cities in Saudi Arabia seven in the eastern province Dammam, Abqaiq, Al Ahsa, Hafr Al Batin, Khafji, Qatif, and Khobar and two in western province Madina and Taif. The lowest average radon concentration 8 Bq∙m −3 was found in Ahsa while the high-
Radon exposure for such long time is necessary in order to obtain relatively a good number of tracks and to be counting statistically. The calibration factor used for conversion of track density (track/mm 2 .day) to radonconcentrations in (Bq/m 3 ) is 0.12423track.mm -2 per Bq.day.m -3 . The background has been calculated by calculating and subtracting from the track density of each track detector which was exposure to a period of measurement. The radiological risk associated with indoor radon exposure and relevant regulation has been evaluated. Regulations vary greatly between countries. The United States of America (USA) use a reference level of 148Bq/m 3 for dwellings and 400Bq/m 3 for workplaces (USEPA, 2004) . The European Union (EU) accepts the recommended action level, the radiation level above which preventive action must be taken, included in the International Commission on Radiological Protection (ICRP, 1965)  of between 500 and 1500Bq/m 3 given by Kavasi et al., 2006 , and ICRP, 2009  has identified the limit of radon concentration for the population to be (200-300 Bq/m 3 ) (ICRP, 2009) . In the United Kingdom (UK) the Health and Safety Executive (HSE) given by Kendall et al., 2005  has adopted a radon action level of 400Bq/m3 for workplaces. Also the limit is populated to be (148Bq/m 3 ) in Environmental Protection Agency (EPA) (EPA, 2003) . In Hangary the action level for workplaces is 1000Bq/m 3 (Kendall et al., 2005) . While Israel uses a reference level between 40 and 200Bq/m 3 (Akerblom, 1999) . There are no specific regulations in Iraq for indoor radon levels in either dwellings or workplaces. Department of Chemistry Building consists of several unites including laboratories preliminary studies and laboratories graduate addition to the private rooms of the masters. Among 68 suspended detectors, 6 have been lost. The results of the measurements at 1m and 1.75m for the department of chemistry are as follows:
Variations in radon concentration have generally been observed in connection with seasons. Radonconcentrations in groundwater of the same well vary between wet and dry seasons (Figure 3). Generally, radonconcentrations were slightly high in the dry season and low in the wet season. The low radonconcentrations would be expected in the wet season due to the effects of dilution in a large volume of water as a result of recharge from nearby river or infiltration from rain water. However, wells B9, B17, D4, and D8 showed the opposite results (i.e. high radonconcentrations in the wet season and low in the dry season). This was probably due to infiltration of rain water containing high dissolved radon as a result of the dissolution of soil gas during movement through the unsaturated zone.
Researchers have realized that radon-contaminated air inside buildings is a principal way of human exposure to certain healthy-risks. A model is developed to estimate radonconcentrations which consider various parameters: in indoor air radon (radon-222) concentration, air permeability of ground, air pressure difference between outdoor and indoor at ground level, ventilation of building ground and number of air changes per hour due to ventilation. The radon-222 transport into building might dominated by diffusion, pressure driven flow or/and a mixture of both depending on the actual values of the various parameters. So, in several and regular periods of time: January, April, July and October, radon-222 concentrations have been measured in ten rooms of five elementary schools and in five rooms of one high school at Qena city (Upper Egypt). This has been carried out using alpha scintillation counters. We have noticed that in three rooms the value has exceeded 200 Bq·m −3 at the basement and only one room at the first floor, and all values have changed with respect to time and localization: They have decreased from July to January and from basement to first floor. For example, radon-222 concentrations obtained by exposing track detectors varied in the range from 20 Bq·m −3
U, 232 Th, 40 K and 222 Rn) in different types of water samples at Al-Hurrah City in Najaf province/Iraq using NaI (Tl) and RAD-7 detector. Materials and Methods: Samples have been collected from three major sources of water, City Water (Drinking Water), River Water and Underground Water. The daily consumption of these three sources by humans in construction materials determines the standards used to measure the Radiological Contamination in these sources such as Annual Effective Dose, Radium Equivalent, Absorbed Dose rate, External Hazard Indexes, Internal Hazard Indexes and Activity Concentration Index Due to Gamma Ray of long-live Radioisotopes. Results: The results show that the average of Radioactivity Concentration for Radium-232 were 1.84±0.39Bq/L, 2.31±0.43Bq/Land 7.15±1.88Bq/L, for Thorium-232 were 1.31±0.33Bq/L, 0.98±0.13Bq/Land 2.19±0.44Bq/L, for Potasium-40 were 9.07±1.32Bq/L, 22.29±2.93Bq/Land 40.89±8.93Bq/L and for Radon-222 were 35.5±0.00 mBq/L, 355.50±30.33 mBq/L and 712.00±97.20 mBq/L. Based on Gamma Radionuclides measurement, the mean annual effective doses of city water and river water are lower than the reference level of the effective dose recommended by the ICRP, while the mean annual effective doses of underground water were higher than the reference level of the effective dose recommended by the ICRP. Conclusion: Finally, the researcher found that all the radiological parameters such as Ra eq ,
geological analysis by the British Geological Society has re- cently resulted in the publication of higher resolution maps (Miles et al., 2007) showing areas of high radon potential within the study area and revised BRE guidance for domes- tic housing (BRE, 2007). The 2007 maps indicate that in the village of Coniston, greater than 30% of the homes are above the Action Level, although the area of Coniston Cop- per Valley is identified as potentially having between 0–1% and 1–3% of homes above the Action Level. This may be because there are very few homes close to the mines that the immediate area is shown as a relatively low radon area. The Smallcleugh and Hudgill Burn mines on the other hand occur in the Nenthead area in Cumbria and this region is identified as having between 5–10% and 10–30% of existing homes with radon levels above the Action Level in the 2007 map guide (Miles et al., 2007).
The RAD-7 is a true, real-time continuous radon monitor. This means that a varied radon concentration level can be observed during a measurement period. This is very helpful, in the sense that one can investigate the fac- tors influencing the radon concentration with time. The factors may include temperature changes, wind speeds, relative humidity and may even give insight into air movements in a room . Figure 1 shows RAD-7 electron- ic continuous radon monitor.
Radon and its radioactive progenies in indoor places are recognized as the main sources of public exposure from the natural radioactive sources. The tap water used for drinking and other household uses can increase the indoor radon level. In the present research data on radonconcentrations in the water samples of Mashhad city has provided. Water samples were collected from various places and supplies of public water used in Mashhad. Then radon concentration has been measured by PRASSI system tree times for each sample in this Result shows about 75% of water samples have radon concentration gather than 10Bq/L which advised EPA as a normal level. According to measurements data, the mean radon concentration of all samples was 16.238 ± 9.322 Bq/L. The annual mean effective dose in stomach and long are 42.674 ± 24.525 and 45.305 ± 26.037 μSv/y, respectively, per person of Mashhad population which is more then 4 millions people. Results show about 75% of water samples have radon concentration gather than 10Bq/L as advised of EPA normal level. The radon and radium concentrations in drinking water samples actually used by people in Mashhad in some regions are not low enough and below the EPA proposed limits. Since a main section of radon come in to drinking and household water, and for improvement of the social health level, we suggest using the low radon level water source, or public water supplies authority reducing the radon in the drinkable water before using by people.
When an ecological approach was adopted using NRPB data on localities, the results were generally negative with (excluding the small number in the highest category) a flat distribution. This points to characteristics in the individual households as possibly being important in determining radonconcentrations. As it was recognised in this (and other) case – control study that socioeco- nomic differences occur between cases and controls and between interviewed and first choice controls (UKCCS Investigators, 2000), this area seemed to be likely to hold the possible explanation of the negative trend. Indeed this appears to be the case, when features likely to cause variability of household radon concentra- tions and census variables are analysed following the work of Wrixon et al (1988) and Gunby et al (1993). This view is supported by direct studies of case – control differences in double glazing, central heating and dwelling above ground level, which all suggest that controls with a higher ‘socioeconomic status’ (i.e. more likely to have double glazing, central heating and less likely to be a flat dweller) are more likely to be interviewed. Even when controls with low levels of radon concentration occur, the case equivalents are even lower. This could then lead to the negative trend seen across all diagnostic groups.
Seventeen thermal spas participated in this study, representing about 46% of all thermal spas existing in Portugal (Fig. 1). For each studied thermal spa, the radonconcentrations were measured in the natural mineral water from different sampling points: boreholes (BH), springs (SG), inhalator chambers (ORL´s) and swimming pools (SP) and in the indoor air of different rooms: ORL’s, swimming pools (SP), vapours areas (VA) and Vichy shower (VS). The measurements were carried out between November 2013 and September 2014. The assessment of radon concentration included measurements in two different periods (summer and winter) in the indoor air of the selected thermal spas. Regarding the assessment of radon concentration in water a single measurement was carried out directly in the water from the borehole and in the water used in the treatment rooms. Measurements of gamma radiation doses were also assessed in some of the previous locations.
sponge layer. The radon dosimeter containing CR-39 (with an area 1 x 1 and 500 at its bottom. The design of the chamber ensures that the aerosol particles and radon decay products are deposited on the sponge from outside and that only radon diffuses through it to the volume of the chamber (Al-Jarallah et al., 2008).  The radon dosimeter was used to determine the indoor radonconcentrations as shown in the figure (1). The exposure time was 90 days. At the end of the exposure time, the radon dosimeters were collected and the detectors were removed, and then treated using etching solution NaOH with 6.25N in water bath at 70±1°C for 7 h. Then, the CR-39 detectors were washed with distilled water and dried. The tracks produced were counted using optical microscope with 400x magnification as shown in figure (2).
following the sediment equilibration technique described in Corbett et al. (1998). Briefly, 1 kg sediment samples were obtained from two soil layers below the surface up to 1 m depth. Samples were only taken from this depth as shallow groundwater is the major interacting groundwater source with the surface water due to the presence of a 10 m thick layer of gel- like marine/estuarine clay that exists >1.5 m from the surface. This deeper sediment has a very low hydraulic conductivity (White et al., 2003), and acts as a confining layer between any deeper groundwater aquifers. Known volumes of radium-free tap water equilibrated with the atmosphere was added to the sediments and incubated for 21 days to allow for radon source ( 226 Ra decay) and sink ( 222 Rn decay) to reach steady state equilibrium. The radon concentration in the water was then measured on a RAD7 using procedures described above. The radonconcentrations from each sediment incubation were averaged to provide an integrative groundwater radon endmember. This technique is a widely used approach for estimating the radon endmember in groundwater discharge studies (Burnett et al., 2007; Peterson et al 2008; Schmidt et al., 2010).
The purpose of this study is to measure the concentration levels of radon-222 from seven (7) water samples collected at different sachet drinking-water companies located within Dutsin-Ma LGA using Liquid Scintillation Counter. The levels of radon-222 found to range from (11.69 to 13.04 ), and (9.23 to 11.19 ) with mean values of 12.37 and 10.18 for borehole and earth-dam sources respectively. The results found are compared with the world average maximum contaminant level (MCL) of 10 set by WHO and it was discovered that 86% of the samples are below the value and 100% of the samples are below the WHO recommended reference level of 100 . Annual effective doses due to ingestion of radon in water for three (3) categories of people were estimated from the measured radonconcentrations and their mean values were found to be (0.090, 0.181 and 0.632) in borehole water and (0.074, 0.149, and 0.520) in surface water (earth-dam) for adults, children and infants respectively. Most of the mean values of the annual effective doses were below the recommended level of 0.1
The concentrations of radon and its progeny inside a given dwelling depend on numerous factors, the most important of which are the uranium concentrations both in the soil surrounding the dwelling and in the building materials themselves, atmospheric conditions, architec- tural style (for example, whether there is a slab basement, a crawl space, etc.), porosity of the surrounding soil, building layout, and the ventilation habits of the inhabi- tants of the building. The large variability in the factors listed above contribute to potentially large variability in indoor radonconcentrations and motivate detailed, na- tion-wide indoor radon surveys such as that described here.
The present work is aiming to determine the radonconcentrations and radon exhalation rate in the phosphate rocks samples from Safaga and El- Hamrawayn areas in the Eastern Desert along the beach of Red Sea. In order to detect any harmful radiation that would affect the human and radioactivity background level this, can be used as reference information to assess any changes in the radioactive background level in order to detect any harmful radiation that would affect the human and the environment.