Assessment of indoor radon doses received by the students in the Azad Kashmir schools, Pakistan.
Several epidemiological studies conducted on thousands of underground miners suggest that long- term exposure to high radon concentration can increase the risk of lung cancer. Keeping in view the importance of the subject, numerous studies throughout the world have been carried out to measure indoor radon concentration and its resulting doses at occupational and non-occupational sites. The purpose of the current study was to measure indoor radon concentration and its resulting doses received by the students of Azad Kashmir government schools. For this purpose, CR-39 radon detectors were installed in 80 carefully selected schools. The detectors were placed at a height of 3-5 ft. (depending upon average height of students in particular class) from the ground. After exposure of 90 d detectors were etched for 9 h in 6 M NaOH at 70°C and the observed track densities were related to radon concentrations. The measured indoor radon concentration ranged from 22 ± 9 to 228 ± 3 Bq m(-3) with a mean value of 78 ± 5 Bq m(-3). Based on the measured indoor radon data, the annual effective doses were found to vary from 0.55 ± 0.04 to 0.71 ± 0.03 mSv y(-1). The overall mean effective dose for the studied area was found to be 0.63 ± 0.04 mSv y(-1). Reported values for radon concentrations and corresponding doses are lower than ICRP recommended limits for workplaces.
Rafique
Muhammad
M
Department of Physics, University of Azad Jammu & Kashmir Muzaffarbad, 13100 Azad Kashmir, Pakistan. rafi_722002@yahoo.com
Rahman
S U
SU
Rahman
Said
S
Matiullah
Shahzad
M Ikram
MI
Ahmed
Navid
N
Iqbal
Javid
J
Ahmed
Basharat
B
Ahmed
Tanveer
T
Akhtar
Nadeem
N
D000396:Air Pollutants, Radioactive / Q000032:analysis*; D016902:Air Pollution, Indoor / Q000032:analysis*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D010154:Pakistan; D011829:Radiation Dosage; D011834:Radiation Monitoring; D011886:Radon / Q000009:adverse effects* / Q000032:analysis*; D012574:Schools / Q000706:statistics & numerical data*; D013334:Students / Q000706:statistics & numerical data*
D000396:Air Pollutants, Radioactive; D011886:Radon