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Assessment of Indoor Gamma Radiation and Related Annual Effective Dose in Zanjan, IRAN
F Saghatchi, A Eslami, M Salouti,
Volume 2, Issue 2 (9-2009)
Abstract

Backgrounds and Objectives: Due to importance of ionizing radiation on human health, many studies have been performed to measure the background gamma radiation all around the world as well as some cities in lran. According to this fact that everybody spends almost 80% of his time in indoor areas, this study was carried out to measure the amount of background gamma radiation in indoor areas in Zanjan city located in northwest of Iran to determine the annual effective dose of the city residents.
Materials and Methods: To determine the dose rate of background gamma radiation in indoors, 30 dwelling (in the main geographical directions and in the downtown areas) were selected. All of them were one floor and iron roofed. A Geiger-Muller detector (RDS-110) calibrated by Cs-137 was used in each livings room of each dwellings that performed in one meter far from the earth. In 30 minute 30 values was recorded. The mean value was considered as indoor gamma dose rate in each dwelling.
Results: The mean value of dose rate in Zanajn indoor areas due to gamma background radiation was determined 146±25 nGy/h. According to the results and findings in our previous study about gamma background radiation in outdoor areas in Zanjan, the annual effective dose was determined and 0.87 mSv for Zanjan city residents.
Conclusion: The annual effective dose of Zanjan city residents due to the gamma background radiation is 0.87 mSv that in comparison with UNSCEAR-2000 report is higher than the mean value for the world (0.48 mSv).


Comparison of Numerical Simulation of NOx with Modeling of IAQX in Indoor Environments
M Shafiepourmotlagh, M Kalhor, F Khalil Arya,
Volume 4, Issue 2 (9-2011)
Abstract

Background and Objectives: This study presents an evaluation between IAQX 1.0f and Fluent 6.3.26 in modeling of NOx dispersion in an indoor residential environment. Modeling predictions are compared with sampling results.
Materials and Methods: Aresidential building with about 84 m2 area is modeled. In IAQX 1.0f the building is divided into five zones. Emission factors and absorption rate of sinks is estimated with US.EPA suggested factors. On the other hand, In the Fluent 6.3.26 model, the building was divided into 1777 cells, and the openings are defined by the boundary conditions of the inflow. In this model, pollution sources were simulated by boundary conditions of the mass inflow.
Results:Compared to IAQX 1.0f, Fluent 6.3.26 showed higher estimation of the concentrations in the zones of 1, 2 and 3. In comparison with the measurements, both models had underestimated results.
Conclusion: The results of Fluent 6.3.26 were closer to the sampling results in the zones.

 

 


Relationship between the Particulate Matter Concentrations in the Indoor and Ambient Air of the Tehran Children Hospital in 2007
Soheila Rezaei, Kazem Naddafi, Hossain Jabbari, Masoud Yonesian, Arsalan Jamshidi, Abdolmohamad Sadat, Alireza Raygan Shirazinejad,
Volume 6, Issue 1 (5-2013)
Abstract

Background and Objectives: In recent years exposure to fine airborne particles has been identified as an important factor affecting human health. Epidemiological studies have showed that the aerosol laden air can be an agent for microorganisms’ dispersion. Ignoring internal sources, ambient air quality significantly affects indoor air quality. Since people spend most of their times in the indoor spaces and little data are available on the general understanding of the indoor air quality, therefore, the aim of this study is to determine the particulate matter concentrations in indoor and ambient air of Tehran Children Medical Center Hospital.
Materials and Method: PM10/PM2.5 samples were collected in the indoor environment of the Tehran Children Medical Center Hospital and its adjacent outdoor environment by a portable GRIMM dust monitor model 1.108 from November 26 to March 10, 2007. The places of sampling for indoor and ambient air were in the patient room and the roof of the hospital respectively.
Results: The results showed that indoor PM10 level was higher than WHO standards in 80% cases in patient room, whereas, for indoor PM2.5 level, this value was 42 and 64% more than the EPA standards and WHO standards respectively. The relationship between outdoor and indoor particulate matters was examined by linear regression analysis. The indoor particulate matter levels were correlated with the corresponding ambient air ones.
Conclusion: Our analysis revealed that infiltration of ambient air could substantially increased indoor pollutants and thereby influences the indoor air quality.


Microwave emission in indoor sites in the vicinity of macro cellular base stations in Zanjan
A. Bazargani, M. Yunesian, M. R. Monazzam, A. H. Mahvi,
Volume 7, Issue 3 (5-2014)
Abstract

Background and objectives: In recent decades, progress of telecommunication industry resulted in public availability to cost-effective cellular mobile hence, boom of base stations of cellular mobile in response to vast public demands. Base stations of cellular mobile are specific source of microwave production in a certain frequency in environment. Antennas are installed on high towers to create proper coverage. General public exposure because of possible health effects resulting from radiofrequency fields has become challenging problem. The purpose of this study was to investigate microwave radiation status in actual exposure in inside buildings vicinity of macro cellular base stations in Zanjan. Materials and methods: considering location of base station antenna in city, power density of microwave around 64 base stations in indoor sites such as health care places and residential areas at different distances and different heights was measured. Measurements were performed based on IEEE Std C95.1 standard method using a portable SPECTRAN, HF– 4060 Rev. 3. Analyzing of data was conducted using SPSS Ver. 18 software and statistical tests like Kolmogorov-Smirnov, univariant variance, and multi variant linear regression. Results: It was found that the maximum level of power density was measured at a distance of 20 m from base station about 0.03787mW/m2. With increasing distance from base station, the density of wave power decreased. Minimum measured at a distance of 300 m from tower was 0.00108mW/m2. The positive variation of power density with height increase was shown. Conclusions: The maximum level of power density among total of 252 measurements, in indoor sites was7.320mW/m2. This is about 0.166 % of the Permissible Exposure Limits of the standards for public exposure. We did not consider factors such as building location and interior furniture. Therefore, we suggest such factors be included in the future studies.


Investigation of Fungal Bioaerosols and Particulate Matter in the Teaching-Medical Hospitals of Khorramabad City, Iran During 2015
A Sepahvand, H Godini, Y Omidi, M.j Tarrahi, R Rashidi, H Basiri,
Volume 9, Issue 1 (6-2016)
Abstract

Background and Objective: The presence of fungal bioaerosols in hospitals indoor environments have affected the health of patients with the defect in immunity system. Therefore, determination of the rate and species of these agents is essential. This study aimed to investigate association between fungi contamination and particulate matter (PM10, PM2.5 and PM1) concentrations in the main indoor wards and outdoor environment and to determine I/O ratio in two educational-medical hospitals of Khorramabad City.

Materials and Methods: In this description-analytical study, the concentration of fungal bioaerosols and particulate matter was measured in 10 indoor parts and 2 outdoor stations over 6 mounts. The sampling was conducted using Quick Take-30 at an airflow rate of 28.3 L/min and sampling period of 2.5 min onto Sabouraud dextrose agar medium containing chloramphenicol. The particulate matters were measured using Monitor Dust-Trak 8520. Moreover, the relative humidity and temperature were recorded using digital TES-1360.

Results: Analysis of 288 fungi samples and 864 particulate matter samples showed that the average of fungi accumulation was 59.75 CFU/m3 and the mean concentrations of PM10, PM2.5 and PM1 in the indoor environment was  27.3, 23, and 20.2 µg/m3 respectively. In addition, in ambient air the mean concentration was 135.3 CFU/m3 for fungal bioaerosols and 40.2, 35.7, and 29.8 µg/m3 for PM10, PM2.5 and PM1 respectively. At the total of fungi samples, 12.5% were negative and 87.5% were positive. Having 101.7%, Infection ward was the most contaminated ward. The operation ward in both hospitals showed the minimum fungal contamination.

Conclusions: The results of the present study showed that at all of the samplings the ratio of I/O was lower than one. It was noticed the dominancy of fungal bioaerosols and particulate matter of outdoor source on the indoor environment. In addition, a significant correlation (P < 0.001( was found between fungal bioaerosols frequency and particulate matter and as well as fungal bioaerosols frequency, relative humidity and temperature.


Measurement of radon concentration in indoor air of residential and public buildings in Nourabad Mammasani city and estimation of its effective dose
H Hassanvand, N Dehghan, K Naddafi, Ms Hassanvand, R Nabizadeh, S Faridi, Z Yousefi,
Volume 11, Issue 4 (3-2019)
Abstract
Background and Objective: Radon gas is one of the environmental risk factors which can increase the risk of lung cancer and it is well known as the second-leading cause of lung cancer after smoking. The aim of the present study was to investigate indoor radon gas concentration in residential and public environments of Nourabad Mammasani city and to estimate the effective dose due to radon exposure.
Materials and Methods: In this study, 52 homes and 8 public places were investigated to measure the concentration of indoor radon gas. Indoor radon concentrations were measured using passive sampling approach, alpha-track detectors (CR-39) for three months, and after that, detectors were sent to the laboratory to count the number of tracks.
Results: The results of this research showed that the average radon concentration (± SD) in the homes and public places was 42.4(±14.7) and 32.9(±20.1) Bq/m3, respectively. All radon concentration values were lower than the US Environmental Protection Agency standard and WHO guideline. The average of annual effective dose due to the radon exposure in homes was estimated to be 1.07 mSv. The evaluation of the results showed that there was a significant relationship between the room type and the number of floors with radon concentration in the residential buildings.
Conclusion: The results indicated that the indoor radon concentration as an environmental risk factor in the studied places was lower than the WHO guideline levels. Consequently, the indoor radon is not likely a major environmental risk factor in the studied environments.

Sick building syndrome symptoms among staff in Razi hospital of Chalous, Mazandaran province
Ali Ahmadi Orkomi, Melika Mirchi,
Volume 13, Issue 2 (8-2020)
Abstract
Background and Objective: Since people spend a lot of time indoors, assessment of Sick Building Syndrome (SBS)is the first step to improve working and living conditions in closed environments. This study wasconducted to evaluate the SBS symptoms among staff in Razi Hospital of Chalous, to identify the affecting environmental parameters on these symptoms and to provide solutions to reduce the symptoms of SBS.
Materials and Methods: This descriptive-analytical study was conductedrandomly among 72 out of 240 hospital’s staff. Questionnaire MM040EA was used to collect demographic data, SBS symptoms and affecting environmental factors. Statistical analysis was carried out using Pearson’s Chi-squared test and Fisher's exact test in Excel software.
Results: 60% of people showed moderate to severe SBS symptoms. Fatigue, headache, and sneezing were the most common symptoms among staff, with 85%, 75%, and 63%, respectively. Significant correlation was observed between SBS symptoms and room temperature fluctuations (p <0.001), low ambient temperature (p = 0.037), unpleasant odor (p = 0.043) and gender (p = 0.011) with significance level of α=0.05.
Conclusion: Investigating the influence of work environmental related factors on the general symptoms of SBS as well as on fatigue, headache and sneezing symptoms showed room temperature fluctuation and unpleasant odor as the most important driving factors. These symptoms were mainly due to the improper air conditioning system operation at the hospital to control the temperature. Therefore, it is expected that the prevalence of SBS among staff can be reduced significantly by improving the ventilation system performance, especially in winter.

Concentration and source identification of polycyclic aromatic hydrocarbons in office building dust of Isfahan metropolitan, Iran
Qasim Jalal Smian, Soheil Sobhanardakani, Atefeh Chamani,
Volume 16, Issue 3 (12-2023)
Abstract
Background and Objective: Nowadays, individuals spend a lot of time indoors; thus they are exposed to hazardous compounds including polycyclic aromatic hydrocarbons (PAHs) with teratogen, mutagen, and carcinogen potential. Therefore, this study was conducted to detect, and determine the content and source apportionment of PAHs in office building dust samples of Isfahan metropolis in 2023.
Materials and Methods: In this descriptive cross-sectional study, 84 indoor dust samples were collected from 28 sampling sites. After extraction of analytes, the gas chromatography/mass spectrometry (GC–MS) method was used to determine PAHs content in the samples. Molecular diagnostic ratios (MDRs) were used to determine the origin of PAH compounds. Furthermore, all statistical analyses were performed by SPSS software.
Results: The results showed that 16 priority PAHs were detected in the office building dust samples with the minimum, maximum, and mean values (µg/kg) of 4575, 16589, and 9838. Moreover, based on the results obtained, the mean contents of NAPH, FLU, PHE, FULA, PYR, BaA, CHR, BbF, BkF, BaP, DahA, BghiP, and IcdP species were higher than the maximum permissible concentration (MPC) established by Iran DOE. The results of the MDRs method indicated that although PAHs originated from both pyrogenic and petrogenic sources, the pyrogenic sources had the main role in the pollution of office building dusts with PAHs.
Conclusion: Due to risks arising from exposure to PAHs, detection, determination of contents, source identification, and especially health risk assessment of PAHs in indoor dust of other closed places such as commercial, educational, and recreational buildings as well as households is recommended.
 

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