Indoor Radon Survey in Dwellings of Nine Different

Indoor Radon Survey in Dwellings of Nine Different Cities of the Eastern and the Western Provinces of Saudi Arabia • • Client: Duration: • Total Budget: SR. 74900/- SABIC-KFUPM 1 -10 -2000 to 31 -6 -2003 Investigators M. I. Al-Jarrallah F. Abu-Jarad Fazal-ur-Rehman A. Al-Shukri B. K. Gadoo

Indoor Radon Survey in Dwellings of Nine Different Cities of the Eastern and the Western Provinces of Saudi Arabia • • Abstract Radon Risk Facilities used in the project Distribution of Radiometers Results Estimation of Annual Lung Cancers Anomalous Radon Concentration! Summary

ﺳﻠﺴﻠﺔ ﺍﻟﺘﺤﻠﻞ ﺍﻹﺷﻌﺎﻋﻲ ﻟﻠﻴﻮﺭﺍﻧﻴﻮﻡ Decay Series of Uranium-238 238 U 234 Th 234 Pa 234 U 230 Th Alpha Decay (4 He) Beta Decay (e) 228 Ra 222 Rn 218 Po 214 Pb 214 Bi 214 Po 218 Pb 210 Bi 210 Po 206 Pb

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.

Radiation Risk from Radon Progeny • 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/m 3. • 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/m 3

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 70 C 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 (Alpha. GAURD) was used to confirm the anomalous radon concentration found in Qatif City

The Passive Radon Radiometer Sponge 6 cm Indoor Air with Radon Plastic Cup 7 cm CR-39 NTD 4. 8 cm

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. %)

Results

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 99 89 71 48 49 71 101

Variation of radon concentration in 98 schools distributed in the different cities City Madina Dammam Abqaiq Khafji Qatif Khobar Ave. Radon Conc. (Bq m-3) 32 15 16 19 18 24 Highest (Bq m-3) 22 44 32 50 70 Lowest (Bq m-3) 10 9 9 1 8 11 11 3 48 24 No. of Schools 1

Estimated cases of annual lung cancer in each surveyed city due to radon City Population Ave. Rn Conc. (Bq m-3) Estimation of Annual Lung Cancers Al-Ahsa 724, 226 8 8 Abqaiq 51, 219 14 1 Hafr Al-Batin 222, 416 21 7 Qatif 161, 087 22 5 Madina 804, 634 25 29 Taif 685, 989 26 26 Dammam 766, 225 29 32 Khobar 221, 530 30 10 Khafji 80, 779 39 5 Total 3, 718, 104 22 119

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 165 154 173 145

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. • 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. In Qatif City one house showed a radon concentration of 535 Bq m-3.

Thank you