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Showing 8 results for Indoor Radon
Dr. K. Kant, Rashmi, R.g. Sonkawade, G.s. Sharma, R.p. Chauhan, S.k. Chakarvarti,
Volume 7, Issue 2 (9-2009)
Abstract
Background: Radon and thoron are invisible, odorless, heavy and radioactive gases which are ubiquitously present in dwellings and in the environment. In the present work, seasonal variation of indoor radon, thoron and their progeny concentrations has been studied in the dwellings of industrially polluted cities in District Faridabad, Haryana and District Mathura in Uttar Pradesh. Materials and Methods: LR -115, Type- II (Kodak Pathe, France), peelable, plastic track detectors commonly known as solid state nuclear track detectors (SSNTDs) were used to measure the radon thoron concentration over long integrated times. The measurements were carried out in the mixed field of radon and thoron and the detectors were exposed for about 90 days. Results: The average value of radon and thoron concentration in the dwellings varied from 23.5 Bq/m3 to 65.2 Bq/m3 and 9.8 Bq/m3 to 18.7 Bq/m3 respectively in different seasons. The average annual exposure and annual effective dose in living rooms due to radon and thoron progeny was estimated to be 0.195 WLM (working level month) and 0.74 mSv respectively. The average life time fatality risk of lung cancer from the chronic radon and thoron progeny exposure was estimated to be 5.8 ´ 10-3 (0.58%). Conclusion: The seasonal variations of measured radon levels in the environment of LPG bottling plant, radon-thoron levels and inhalation dose due to radon and thoron and their progeny in dwellings indicate that the levels were higher in winter (October to January) than in summer (April to July). Iran. J. Radiat. Res., 2009 7 (2): 79-84
K. Hadad, M.r. Hakimdavoud, M. Hashemi-Tilehnoee,
Volume 9, Issue 3 (12-2011)
Abstract
Background: While in the open air the amount of
radon gas is very small and does not pose a health
risk, in confined spaces, radon can accumulate to
relatively high levels and become a health hazard.
Exposure to high levels of radon has been associated
with an increased risk of lung cancer, depending on
the time length of exposure. Radon level in dwelling
of Shiraz with 1,200,000 populations has been
sampled and analyzed in this study. Our study could
be considered the largest radon study in Iran both
time and area wise. Materials and Methods: In this
study, radon (222Rn) concentration in residential
dwellings in Shiraz-Iran was sampled and measured
during two consecutive six month periods in 2009-
2010. We used Solid State Nuclear Track Detectors
(SSNTD), CR-39 polycarbonate films. The survey
parameters of radon concentrations were floor types,
construction materials and dwelling’s age. Results:
Annual average indoor radon concentration for the
survey period was 94±52 Bq/m3. The calculated
mean annual effective doses in basements and
different floors were less than the lowest limit
recommended action level of 3 mSv by ICRP.
Conclusion: High radon concentrations are measured
in basements and old dwellings however, due to
rapidly changing housing structures and ventilation
practices with no intervention, lower levels of radon
concentration has been expected in Shiraz. Iran. J.
Radiat. Res., 2011 9(3): 175-182
Dr. M. Rafique, N. Manzoo, S. Rahman, S.u. Rahman, M.u. Rajput, Matiullah,
Volume 10, Issue 1 (6-2012)
Abstract
Background: Several epidemiological studies
conducted on underground miner’s show that
exposure to elevated levels of radioactive radon gas
is expected to increase the risk of lung cancer.
Relative risk of lung cancer is almost linear with
radon exposure. Elevated concentrations of radon are
not only reported within mines but also for closed
indoor environment of general public houses.
Measurements of radon play a serious role in
scrutinizing public health and safety in homes.
Materials and Methods: Indoor radon measurements
were taken over a period of year, using CR-39
detectors. Measured indoor radon concentrations,
was converted in to excess relative risk (ERR) factors
by using the risk model reported in the Biological
Effects of Ionizing Radiation (BEIR VI) report. ERR was
calculated for age groups of 35 and 55 years. A
careful selection of occupancy factor based on
interviews with house occupants has been made.
Results: Using this local occupancy factor, average
excess lung cancer risk for the age group of 35 and
54 y peoples was found to 0.51±0.03 and
0.42±0.03. Similarly average values of ERR for local
occupancy factor with ages 35 and 55 years was
found as 0.59±0.03 and 0.45±0.03. Conclusion: The
overall average excess lung cancer risk for the
studied area was 0.46±0.03. The study suggested
that United State Environmental Protection Agency
(US EPA) occupancy factor gave a higher excess lung
cancer risk as compared with the local occupancy
factor used for studied areas. The ERR due to indoor
radon is within the standard limits and does not pose
any serious threat to the occupants of the houses
under investigation. Iran. J. Radiat. Res., 2012 10(1):
19‐29
Dr. H. Al Zabadi, K. Mallah, G. Saffarini,
Volume 13, Issue 3 (7-2015)
Abstract
Background: Many public health agencies rank residential radon exposure as the second leading cause of lung cancer after cigarette smoking. It has been shown that the risk coefficient for lung cancer is higher for children than that for adults. Therefore, indoor radon measurements were carried out in the elementary schools of Tulkarem province, West Bank, Palestine. Materials and Methods: Two hundred and thirty solid state nuclear track detectors (SSNTDs) type CR-39 were distributed in the classrooms of 20 elementary schools in Tulkarem province area. About thirty of them were used for quality assurance purposes. The CR-39 detectors were exposed in the schools for three months during the school summer holiday from May 2012 to August 2012 and then collected and etched in Sodium Hydroxide (NaOH) 6.25 N solution at 75 °C for 6 h. The tracks were counted manually at the digital microscope. Results: The indoor radon levels were generally low, ranging from 3.48 to 210.51 Bq/m3 (Becquerel per cubic meter), with a mean radon concentration (mean±SE standard error) of 40.42± 2.49 Bq/m3. The average annual radon effective dose was assessed to be (mean±SE) 0.17 ± 0.01 mSv/y (milliSievert per year) while the excess lifetime lung cancer risk was approximately 0.09%. The results obtained indicate that the indoor radon concentration was significantly affected by the floor level of the classroom (negatively correlated) and the school building age (positively correlated). Conclusion: The radon concentration and the resulting dose in the schools were within the reference levels of the International Commission on Radiological Protection (ICRP). Better ventilation is recommended to decrease the risk to the minimum.
M. Fahiminia, R. Fouladi Fard, R. Ardani, A. Mohammadbeigi, Dr. K. Naddafi, M.s. Hassanvand,
Volume 14, Issue 4 (10-2016)
Abstract
Background: Inhalation of radon and its short-lived decay products is one of the most significant sources of exposure to natural radiation. Radon is the second cause of lung cancer in the populations. The present study was carried out under the projects of national radon, with the aim of determining the concentration of indoor in the city of Qom located in the central semi-arid region of Iran. Materials and Methods: Radon measurements were carried out in 123 dwellings using passive sampling with CR-39 detectors for 90 days. The map of radon concentration distribution was prepared using Arc GIS software and the statistical analysis was performed with SPSS version 20. Results: Indoor radon concentrations in Qom dwellings ranged from 15–259 Bq m-3. The arithmetic mean of indoor radon concentrations on basement, ground floors, first floors and second and upper floors were 123.43, 87.94, 63.72 and 40.69 Bq m-3, respectively. Conclusion: A correlation was found between the distances from fault zones and measured indoor radon concentration. In most of cases, radon values were lower in well- ventilated dwellings in comparison with poorly-ventilated ones. Moreover, high radon concentration levels were observed in basements. The results indicated that in 30 places (24.3% of cases), the radon concentrations were higher than the reference levels recommended by the World Health Organization (100 Bq m-3).
S. Yassin, M. Al Sersawi, Phd., S. Abuzerr, M. Darwish,
Volume 17, Issue 4 (10-2019)
Abstract
Background: Worldwide, indoor radon exposure is considered to be the second leading cause of lung cancer, particularly among people who stay indoors for a long time as the children and the elderly. The goal of this study is to get a better understanding of indoor radon levels in the houses of the Gaza governorate. Materials and Methods: One hundred eighty passive diffusion radon dosimeters containing CR-39 solid state nuclear track detectors (SSNTD) were distributed in the rooms of the Gaza governorates houses following a cluster random sampling. Only 154 dosimeters were found in the places and collected, while the remaining 26 dosimeters were lost. The detectors were left for two months during the period from March to June of 2006. Variability between dwellings neighborhoods, floors, rooms at the same floor, ventilation status, smoking, dwelling age were assessed. Results: The indoor radon concentrations in the houses of Gaza governorate were lower than the EPA and ICRP recommended limits (150 Bq/m3), with a mean indoor radon concentration (mean±SD) of 40±14 Bq/m3 and a range from 3 to 105 Bq/m3. The house ventilation status was the key variable which affects the indoor radon level, since badly ventilated houses had higher indoor radon concentrations, particularly in the basement floors rather than the higher floors. Conclusion: Despite fulfilling the international limits, we strongly recommend conducting a wider national survey for natural radiation measurements and mapping radon-borne areas throughout the country. Moreover, well ventilation of the house indoor environment is highly recommended.
M. Haghani, Phd., K. Haddad, Phd., S.m.j. Mortazavi, R. Faghihi, A. Pirouzmand, M. Faraz,
Volume 18, Issue 1 (1-2020)
Abstract
Background: Indoor levels of 222Rn in some residential areas in Ramsar are as high as 31,000 Bq/m3, resulting in mean internal exposures up to 71 mSv/y. The main goal of this study was to develop a simple mathematical model for predicting radon concentrationfrom gamma radiation level in dwellings located in high background radiation areas (HBRAs) and a nearby normal background radiation area (NBRA) of Ramsar. Materials and Methods: The levels of gamma background radiation and indoor radon were measured in 350 dwellings located in normal and high background radiation areas (210 dwellings from HBRAs and 140 dwellings from NBRAs). Moreover, data about the most important environmental factors such as temperature and humidity as well as the inhabitants’ nutrition were collected. Results: The mathematical relationship between the gamma radiation level and indoor radon concentration in NBRAs and HBRAs is introduced in this study. The findings obtained in this study clearly indicate that in normal and high background radiation areas of Ramsar the majority of confounding factors such as the type of building materials and ventilation in different houses are almost identical. Therefore, the level of gamma radiation can be used as a strong predictive tool for radon concentration. Conclusion: As radon concentration in indoor air strongly varies with time, the simple mathematical methods developed in this study, can help health physicists and environmental scientists have an estimate of the mean radon level in these areas.
Ph.d., W.a. Alhamdi, K.m.s. Abdullah,
Volume 20, Issue 2 (4-2022)
Abstract
Background: Among the natural radioactive sources, two-thirds of radiation dose received by living tissue is caused by radon and its progeny because it can interact with biological tissue when it is inhaled or ingested. Accordingly, this study planned to measure indoor radon and evaluates its doses in addition to studying metrological parameter to understand the correlation between them. Materials and Methods: This study focused on the indoor radon concentration by two different protocols which are short term and long term. In short term, radon concentration was measured in seven dwellings in Duhok city at the beginning of both winter and summer using RAD7 detector and Airthings Corentium monitor. Then annual effective dose of radon and its decay product to the inhabitance were estimated. In long term protocol, radon concentration was measured continually for one year by fixing Corentoum detector in one building. Results: outcomes showed that the concentration of radon is higher in winter than summer; with range of 1-56 Bq m-3. The average level of indoor radon concentration in both seasons was 19 ± 6.1 Bq m-3. The radon and its progeny average annual effective dose were 0.59 ± 0.17 and 0.23 ± 0.14 mSv y-1 in winter and 0.37 and 0.15 mSv y-1 in summer respectively. Conclusion: The results of average indoor radon concentration obtained were considerably less than the action levels prescribed by ICRP. Also, the results indicated that radon concentration negatively correlated with wind speed and positively with outdoor temperature while outdoor humidity effect has almost neglected.
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