Spatiotemporal Distribution of PM10 and PM2.5 within and Around The City of Arak, Iran: Effect of Natural Sources

In the present study, the concentrations of PM10 and PM2.5 were measured within and around the city of Arak from March 2016 through March 2017. The measurements were done every 12 days by means of TSI DustTrak sampler containing specific heads for PM10 and PM2.5. The sampling points included eight stations within the city as well as two stations around the city. The average (±SD) values of 108.56 ±55.56 and 42.58 ±15.88µg/m3 were obtained for daily concentrations of PM10 and PM2.5, respectively. PM10 showed the maximum concentrations during summer (144.47µg/m3) followed by spring (109.44 µg/m3), autumn (100.92µg/m3), and winter (77.12µg/m3). On the other hand, the highest values of PM2.5 was observed during winter (44.13 µg/m3) followed by autumn (42.74µg/m3), summer (37.58µg/m3) and spring (33.77 µg/m3). The correlation between PM10 and PM2.5 was highest in winter (R2=0.9288) followed by spring (R2=0.6728), summer (R2=0.6713), and autumn (R2=0.5592). It was concluded that more than 57 and 19% of the PM2.5 and PM10 samples exceeded the Iranian national ambient air quality standards, respectively

A Comparative Study of Photo-Degradation of Atrazine in Aquatic Environments Using UV and UV/Fe (III)-TiO2 Processes

A vast variety of pesticides are used for agricultural pests in Iran. The release of these persistent organic pollutants into water supplies leaves adverse effects on both the environment and public health. This study aimed to compare the photo-degradation of atrazine in the aquatic environment using UV and UV/Fe (III)-TiO2 processes. The effects of parameters including pH, the initial concentration of atrazine, and reaction time on the removal of atrazine in the aqueous phase using ultraviolet radiation (1020 μW/cm2) and UV/Fe (III)-TiO2 were investigated. Residual concentrations were determined using HPLC. Finally, the data were analyzed using SPSS software (version 16) and the graph was made by MATLAB software. The results demonstrated that the atrazine removal rate in both processes was significantly increased in acidic and alkaline conditions. By increasing initial atrazine concentrations, the removal rate was increased in both processes as well. Data showed that at the lower initial concentration of atrazine (0.1 and 1mg/l) the removal rate in UV/ Fe (III) - TiO2 process was more than the UV process. However, at higher concentration, both processes were almost the same and the maximum removal efficiency (99.2% at UV and 99.11% at UV /Fe (III) - TiO2) occurred at pH=11, initial Atrazine concentration of 10mg/L and the reaction time 30 min In conclusion, UV and Fe+3-TiO2/UV process was an appropriate method to reduce atrazine in contaminated water resources

Semi-Quantitative Dermal Exposure Assessment of Lead with DREAM Model in a Lead Mine in Iran

Occupational exposure to toxic substances occurs in a variety of ways. The DREAM model is suggested for assessing skin exposure using preset values. The purpose of this study is to investigate the exposure of lead in workers at a mine lead using the DREAM model. This research was done in several steps. First, collect information about people and the work environment. Then design the model in Excel2016 by the authors. This research was descriptive-analytic research and included 46 miners. The DREAM model has a total of 33 variables included. In the DREAM model, exposure assessment was performed for 9 body parts at task level 2. The DREAM model was completed for 5 jobs. Jobs were in the lab, tunnel-74, tunnel-34, entrance to the tunnel and flotation workshop. The results were calculated for each of the 9 parts of the site for propagation, transfer, deposition, and potential and actual exposures, and eventually total exposures. The DREAM model, in comparison with similar methods, estimates the skin exposure level in a semi-quantitative fashion. This method has been used to estimate skin exposure in a variety of industries. This method was used to assess the skin exposure of workers in a mine, which resulted in training workers and providing personal protective equipment appropriate to the environment

Empirical Study of Knowledge, Attitude and Practice towards to Radiation Health Hazards of Cell Phone: a Case Study on Medical Science Students

The cell phone has become an essential part of life, however, in developing countries, knowledge and awareness of users about its adverse health effects have not enough increased. This study aimed to develop a questionnaire to investigate knowledge, attitude and practice regarding health hazards of the cell phone among college students. In this cross-sectional study, 230 graduate students of University of medical sciences located in Hamadan (western province of Iran) were participated, randomly. A developed self-administered questionnaire was completed by each participant to assess knowledge, attitude and practice regarding health hazards of the cell phone. The data was analyzed using SPSS 21. The results showed that the content validity ratio and the content validity index of the developed questionnaire were 0.915, 0.79, respectively. Cronbach (alpha), as a criterion of the reliability of the developed questionnaire, was also equal to 0.85. The scores of knowledge, attitudes and practice among the students were 7.95±2.5, 74.78±8.8, and 28.91±9.0, respectively. Relative to the maximum achievable scores, the acquired scores of attitudes was more acceptable than the others. Moreover, the acquired scores of the knowledge were more than the practice. The scientific controversy about health risks of the cell phones aggravated the public concerns about not well-known effects and consequently, it supported and motivated good attitude among student users. Moreover, it seems that the lack of proper knowledge about cell phone health hazards and protection principles can influence adequate practices. As low as reasonably achievable (ALARA) principle should be adopted for uses of the cell phone, while a major effort is done for monitoring of its new potential health impacts

Prediction of Highway Noise Pollution Level by Model FHWA -TNM (Case Study: Vakilabad Highway in Mashhad-Iran)

This study aimed to model the noise pollution level in 9th and 11th districts of Mashhad municipality (Vakilabad highway) by using Traffic Noise Model (TNM 2.5). To this end, the equivalent sound level measurement of the 25 high-traffic stations selected along the Vakilabad highway in Mashhad was carried out by the TES-1358 sound level meter, for 6 months and each month for 1 working day in the year’s 2017. Traffic volume data was also measured to level the day by the wood line method and then the total data was introduced to model the traffic noise volume in the area. The assessment of the traffic noise of the study area in the model showed that the average equivalent sound level calculated by the model for the stations measured at Vakilabad highway is 6.51 dB less than the recorded values by the sound meter in the real environment by the average of 78 dB. In addition, the results of this study indicated that the TNM could provide a reasonable prediction of traffic volume and its distribution on the Vakilabad highway in Mashhad, due to providing a similar ranking of areas with low or high noise pollution and also displaying acceptable values of Leq calculated as compared to recorded sound values in the real environment

Body Measurements (Anthropometry): A Case Study of Male Students in Qom University of Technology

The existence of ergonomic training tools and devices improves the educational quality and convenience of students. Non-ergonomic training tools also cause musculoskeletal disorders in students and as a result, they will be less efficient. The purpose of this study was to examine the suitability of the seats available with the body dimensions of the male undergraduate and master’s students of Qom University of Technology. In this research, 60 male undergraduate and master’s male students of Qom University of Technology were selected randomly and 18 physical dimensions of them were measured by an anthropometric calliper with an accuracy of 0.1, 0.05 meter, and also seven important parts of the seat affecting on the body's posture were measured by the meter. Also, feeling or not feeling pain in the 8 parts of the bodies of these students and their feelings about the cause of the pain were asked by questionnaires and for data analysis, was used the SPSS version 22. The height of the seating area was almost appropriate. The length and width of the seat area and the width of backing was smaller than the optimal sizes. The height of the chair elbow was shorter than the optimal amount. The length of chair elbow was suitable, and the backing height from the seat area was not suitable. Only the height of the seat area and the length of chair elbow are somewhat appropriate and the rest of the seat parts are not proportionate to the students’ physical sizes. There was a significant difference between the parameters of undergraduate students and the master's students

A Comprehensive Review on Risk Factors Affecting the Crash Severity

As a matter of growing machinery life, traffic crashes are considered an inevitable source of injuries and costs around the world. Regarding to increasing traffic accident outcomes, controlling the current status is necessary. In this way, identifying risk factors affecting the crash severity is an essential step toward initiating a convincing solution. The core objective of this study was to categorize the risk factors affecting the severity of crashes. Data needed for this study were gathered through searching Web of Science, Google Scholar, and Science Direct databases using the keywords included fatal and crash, injuries and crash, fatal and traffic accident, and injuries and traffic accident. Based on 83 selected studies for review, factors affecting the crash severity divided into five factors and forty-seven sub-factors. The most prevalent sub-factors were age, sex, safety belts, alcohol and drug use, speed, weather conditions, lighting conditions, time of the day and week, vehicle kind, road condition, collision type and crash location. Many risk factors affect crash severity and determination of the most important ones can be a prelude in reducing the effects. Therefore, the conclusion of this review can assist to traffic safety experts, police and contribute to distinguishing and monitoring the risk factors affecting crash severity transportation agencies

Comparison the efficiency of Fenton and Photo–fenton processes for the removal of Reactive red 198 Dye from the aqueous solution

The textile industry produces a large amount of polluted effluents discharged into the environment. Therefore, this research was carried out to compare the efficiency of removal of Reactive red 198 (RR–198) dye by fenton and photo–fenton processes and determine the optimal conditions for maximum removal. This study was conducted on a laboratory scale. The effect of influential parameters, including pH (3–9), Fe(II) concentration (10–200mg/L), H2O2 concentration (25–150mg/L), dye concentration (50–200mg/L) and reaction time (15–90min.) on dye removal was investigated and the optimal conditions were determined according to the maximum dye removal efficiency. The results indicated that the dye removal rate increased as the pH and Fe(II) concentration decreased. The optimal conditions for RR–198 removals from the aqueous solution are pH of 3, Fe (II) concentration of 10mg/L, H2O2 concentration of 50mg/L, the initial dye concentration of 50mg/L, and the reaction time of 15min.. The maximum dye removal efficiency under optimal conditions was 98.82%. The results of this study revealed that the photo–fenton process was superior to the removal of dye compared to fenton process

Investigation of Dust Chemical Compounds Emitted by Electric Arc Furnace (EAF) with a reuse perspective

In the process of steel production by electric arc furnace (EAF), it is found that 10 to 20 kg of dust was emitted per every ton of produced steel. Concerning the pollution potential of emitted dust and its reuse ability, the present study was aimed to determine the chemical composition of the electric arc furnace dust with a reuse perspective. This study was done in a steel factory equipped with EAF. Local exhaust ventilation system is installed on the furnace and equipped with cyclone and venturi scrubber. To analysis of dust compounds were gathered in a cyclone and those left the system, the samples were taken from the cyclone hopper and exhaust fan outlet. Finally, the samples were analyzed by X-ray diffraction (XRD). According to the results, the trapped dust in the cyclone and scrubber were 226.86 and 44.81 kg/hr, respectively. The results obtained from XRD analysis also showed that about 50% of the dust was formed by Fe2O3. The quotient of other compounds such as CaO, MgO, SiO2, and Zn was more than 30%. Conclusion: the results of this study showed that EAF dust composed of a range of elements with different concentrations. Given the high weight of these compounds, reusing some of these elements can be having a positive impact on health and the economy

Fire Risk Assessment and Evaluation of the Effectiveness of Fire Protection Actions in a Combined-Cycle Power Plant

The increasing abundance of fires in industrial buildings has led to the growth of fire risk assessment and protection methods. However, few studies have been performed on the practical application of these risk assessment methods in industrial structures. This study aimed at assessing fire risk and determining the effectiveness of fire control measures to reduce fire-related injuries and fatalities to occupants at a combined-cycle power plant in the northeast of Iran. In the present study, firstly, the fire risk level of the real condition for the occupants, building and contents, and activities were measured using the Fire Risk Assessment Method for Engineering (FRAME). Then, taking into account the fire control measures, the fire risk was recalculated and compared with the acceptable risk level. The results indicated that the occupants’ fire risk level was 1.26 that was above the acceptable level. Furthermore, in the case of a fire, the expected destruction of the control room will be approximately 20%. Assuming a constant fire load modulation via building construction by non-burning materials or up to 10% burning materials, the occupants’ fire risk level will be decreased by 8% compared to the current situation. Also, in the state of designing standard emergency exit routes and using the fire alarm system, the fire risk level will be decreased by 50% and 52%, respectively, compared to the current condition. This study indicated that applying quantitative engineering methods for fire risk assessment can help to find practical solutions to minimize losses and fire-related injuries to industrial building occupants