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Indoor Radon Survey in Dwellings of Nine Different Cities of the Eastern and the Western Provinces of Saudi Arabia. Client: SABIC-KFUPM Duration: 1-10-2000 to 31-6-2003 Total Budget: SR. 74900/-. Investigators M. I. Al-Jarrallah F. Abu-Jarad Fazal-ur-Rehman
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Indoor Radon Survey in Dwellings of Nine Different Cities of the Eastern and the Western Provinces of Saudi Arabia • Client: SABIC-KFUPM • Duration: 1-10-2000 to 31-6-2003 • Total Budget: SR. 74900/- Investigators M. I. Al-Jarrallah F. Abu-Jarad Fazal-ur-Rehman A. Al-Shukri B. K. Gadoo
Abstract Radon Risk Facilities used in the project Distribution of Radiometers Results Estimation of Annual Lung Cancers Anomalous Radon Concentration! Summary Indoor Radon Survey in Dwellings of Nine Different Cities of the Eastern and the Western Provinces of Saudi Arabia
سلسلة التحلل الإشعاعي لليورانيوم238UDecay Series of Uranium-238 238U 234Th 234Pa234U Alpha Decay (4He) Beta Decay (e) 230Th 228Ra 222Rn 218Po 214Pb214Bi214Po 218Pb 210Bi 210Po 206Pb
Abstract • The ICRP, an international regulatory authority in radiation protection has set an action level of 200-600 Bq m-3 for radon concentration in houses. Most countries have adopted an action level of about 200 Bq m-3. • The objective of this radon survey is to get a representative data of indoor radon in 7 cities of the Eastern Province (Khafji, Hafr Al-Batin, Abqaiq, Qatif, Al-Ahsa, Dammam and Alkhobar) • and to compare that with 2 cities in the Western Province (Madina & Al-Taif) • So far the detailed radon data is not avaiable about Saudi Arabia; therefore, this radon survey provides a base line for Saudi Arabia in the Radon World Atlas.
Even though radon was identified in the beginning of the last century, it was not until in late 1960 that a correlation between radon daughters exposure and Lung cancer among Uranium miners was established. Based on eight combined studies, the risk of developing Lung caner increased 14% for a person living 30 years in a house with a radon level of 150 Bq/m3. This risk is close to the 13% increased risk that is estimated by extrapolating results from an analysis of pooled data from 11 underground miners studied. The action level of indoor radon concentration in most countries is around 200 Bq/m3 RadiationRisk from RadonProgeny
Indoor Radon Survey in Dwellings of Nine Different Cities of the Eastern and the Western Provinces of Saudi Arabia Sources of indoor radon in a typical house
Facilities used in the project • Nuclear Track Detector based Passive Radon Radiometer calibrated at NRPB, UK, was used in this survey. • Detectors were etched chemically to obtained the visible tracks using Chemical Etching System at 70C for 9 hours. • Alpha track density representing radon concentration (Bq m-3) was measured using Optical Microscope with complete Image Analyzing System. • An active radon ionization chamber (AlphaGAURD) was used to confirm the anomalous radon concentration found in Qatif City
Sponge 6 cm Plastic Cup Indoor Air with Radon 7 cm CR-39 NTD 4.8 cm The Passive Radon Radiometer
Distribution of Radiometers in different Cities • A total of 1610 radiometers were distributed in the houses and schools of nine surveyed cities with the help of Ministry of Education and Ministry of Health • In Madina region, the radiometers were also distributed with the help of the Imarah because of low response from the two Ministries in this region • Only 847 radiometers (53 %) were collected back after placing them for one complete year in the houses.
Frequency distribution of radon concentration in dwellings of nine surveyed cities in Saudi Arabia
Average radon concentrations in the nine surveyed cities of Saudi Arabia
Histograms comparing the cities with the highest and the lowest radon concentration Lowest Highest 137 115 101 99 89 71 71 49 48
Variation of radon concentration in 98 schools distributed in the different cities
Estimated cases of annual lung cancer in each surveyed city due to radon
Anomalous Radon Concentration in a House in Qatif Ground Floor 294 286 148 163 124 302
Anomalous Radon Concentration in a House in Qatif First Floor 165 154 154 173 145
Summary • The indoor radon concentrations in surveyed cities varied from 1 to 137 Bq m-3 with an overall average of 22 Bq m-3 • The lowest average radon concentration (8 Bq m-3) was found in Al-Ahsa city. • The highest average radon concentration (39 Bq m-3) was found in Khafji City. • Most of the houses showed radon concentration below 40 Bq m-3. • In Qatif City one house showed a radon concentration of 535 Bq m-3. • A complete investigation in this house showed a high radon conc. in all the rooms (120-550 Bq m-3) due to high radon exhalation from the walls and the floors , low ventilation and possible radon leak from underground soil to the house.