Abstract Background: Treatment of waste air containing volatile organic compounds (VOCs) using cheap and environmentally friendly methods is one of active fields in air pollution control. Objective: The aim of this study was to treat air containing triethylamine (TEA) vapor using biotrickling filter inoculated with microbial species decomposing TEA. Methods: This experimental study was conducted in the School of Health affiliated to Qazvin University of Medical Sciences in 2014. Biotreatment was performed with biotrickling filter inoculated with microbial species decomposing TEA for two months. The biotrickling filter was set up with air containing TEA as the sole source of carbon, at Empty Bed Residence Times (EBRT) of 36 sec, and inlet concentration of 84 ppm. Data were analyzed using descriptive statistics. Findings: Treatment of TEA contaminated air was made after an adaptation period of 11 days. Despite an increase in mass loading to 111 g/m 3 /h, TEA was eliminated with 109 g/m 3 /h capacity and 94-100% removal efficiency by zero order kinetics.Elimination capacity and removal efficiency were close to each other and confirmed109 g/m3/h as loading region with critical elimination capacity. Conclusion: With regards to the results, it is possible to treat air containing TEA vapor in biotrickling filter.
Methods: This cross-sectional study was conducted in the winter of 2010 in Qazvin. Measurements were performed by the sound level meter 1353H (TES, Taiwan). The main streets and intersections on the city maps were considered as measuring stations. The levels of equivalent noise, statistical noise, and traffic noise were measured based on the ISO 1999 method approved by the Environmental Protection Organization. Data were analyzed by one sided, two sided, paired t-test. Findings: Of total measuring stations, 63% were found to have equivalent noise level higher than the standard recommended for residential-commercial areas and 24% within the standard levels. Conclusion: In all cities under study, the equivalent noise level was higher than that recommended for residential-commercial areas. The daily equivalent of noise index did not change at different times, indicating a uniform sound level from traffic and acoustic fields.
Background & objective: Safety training is believed to be one of the pioneering safety measures to improve the safety culture in organizations.The aim of this study was to determine the impact of training and technical interventions on providing a work environment with proper safety culture and understanding the risk of dangerous situations at height among construction workers.Methods: In this interventional study, 394 workers of different job groups in construction companies including impact driver operators, masonry workers, ironworkers and concrete vibrating operators were entered.Data were collected using "demographic", "safety culture" and "the risk of dangerous situations at height" questionnaires.Questionnaires were completed and collected in three stages: before the intervention, two months after the first intervention and two months after the second intervention (eight months after the first intervention).The data were analyzed using Bonferron's modulation tests (follow-up tests in variance analysis) and binary logistic regression test in SPSS version 23 software. Results:The findings of the present study revealed the significant impact of safety training on all components of the safety culture and also the empowerment of workers in understanding of risk of dangerous situations at height.The findings of this study, also revealed the significant improvements in safety culture, indicating the role of training along with technical intervensions as crucial factors in improving workers safety in organizations.Conclusion: Industries can prevent occupational accidents and their consequences by adopting proper safety and hygiene measures and engineering design through a coherent training program and achieve a sustainable industrial and development prosperity.In this regard, the findings of the present study showed that conducting training courses by involving workers and encouraging group discussion and expressing the importance of safety in the workplace as well as technical measures can positively influence workers' safety behaviors and promote safety culture.Exchange of views and sharing experiences, well-designed training programs, and devoting enough time can also be effective in promoting safe behaviors.
Background: Obviously, decreasing the work-related musculoskeletal disorders is well achieved through the application of ergonomic design principles however, there are occasions in which the existence of some barriers (technical and economical) can preclude ergonomic improvement and therefore, some organizations rely on correct task performance methods. Objective: The aim of this study was to assess the effect of educational intervention on worker’s knowledge increase, attitude change, and ergonomic habits promotion. Methods: In this interventional study, workers were randomly assigned to one of the two study groups: a case group receiving the ergonomic training (n=75), and a control group (n=75). Ergonomic training program composed of five sessions of 30–45 minutes duration containing issues such as ergonomic science, human body mechanic, upright and awkward postures, pros and cons of upright posture maintenance, and solutions for removal of obstacles, stretch exercise for prevention of musculoskeletal disorders, and workstation adjustment. Data were gathered before and 3 months after intervention by selfreporting questionnaire and checklist. Reliability was assessed by testretest method and the internal consistency evaluated by Cronbach's Alpha. Statistical analysis was performed using χ test, McNemar test, independent t-test, and paired t-test. Findings: Worker’s knowledge significantly increased from 7.97±2.91 to 14.07±1.98 and the attitude change from 14.29±6.5 to 21.63±4.7 three months after educational intervention (p> 0.05). No significant change was observed in control group. Regarding the ergonomic risk factors, our findings were indicative of significant change in general body and feet posture, trunk, neck, and wrist and hands postures while other ergonomic risk factors remained unchanged Conclusion: Results from this study emphasize on necessity of integrated educational-managerial and engineering approach to promote the workplace ergonomic condition as well as considering the substantial role of psychosocial factors such as knowledge and attitude and focusing on personal skills for improving ergonomic habits to achieve a higher level of health promotion among human power.
The effect of mobile phone radiation on human reproduction system is still a matter of debate. In this study, 18 male rabbits were randomly divided into two experimental groups and one control group. Experimental groups received simulated microwaves with the frequency of 950 MHz and the output power of 3 and 6 watts for 2 weeks, 2 h a day. After a week of rest, the microscopic slides from the quada of the excised epididymis were prepared. Then, the diameter of epididymis, the height of epithelium and the number of apoptotic cells in epithelium in study groups were determined. The data were compared using spss software and one-way anova test. The epithelial height and diameter of the epididymis in 3 watt and 6 watt groups had a significant decrease compared to the control group (P < 0.001), while the testosterone level only in 6 watt group was significantly decreased compared to control group. The rate of apoptosis in the epithelial cells of the epididymis had a significant increase only in 6 watt group compared to the control group (P < 0.001). This study showed that the microwaves with the frequency of 950 MHz can have negative impacts on morphometric and apoptotic changes of rabbit epididymis.
Background: Low level physical activity is a risk factor for several chronic diseases and evidences suggest that the level of physical activity is decreasing. Reversing this trend depends on a behavior change by most people. However, the associations between various psychosocial determinants and physical activity are not well understood. Objective: The aim of this study was to predict the stages of change in physical activity behavior of QUMS students by Pender’s model. Method: This cross-sectional survey was carried out at Qazvin University of Medical Science in 2008. A total sample of 222 students completed a self-report questionnaire consisting of an exercise measure, constructs of health promotion model, and assessing the stages of exercise behavior change. A test-retest method was applied to determine the reliability while the Cronbach‘s Alpha used to confirm internal consistency. Face & content validity were confirmed in this study. Also, ANOVA and Path analysis were performed to determine the associations between these constructs and stage of physical activity behavior change. Findings: More than half of students were in inactive stage and exercised for 41.62 minutes a week on average. Exercise self-efficacy, perceived barriers, and perceived benefits were found to be significant predictors of the stage of exercise behavior change among medical students. Only Selfefficacy and stages of change (P<0.001) could directly predict the significant variance of physical activity while other constructs from Pander’s model indirectly influenced the physical activity behavior through mediating stages of change construct. Perceived benefits (P<0.001) directly and perceived barriers inversely (P<0.001) were predictor of stage of exercise behavior. Perceived health status could indirectly influence the stage of change via perceived benefit. Conclusion: Our results indicated that the change in stage of readiness for exercise is probably dependent on the student’s perceptions of exercise self-efficacy, benefits and barriers as well as the perceived health status to engage in physical activity. Furthermore, the results of this study made moderate support for the health promotion model constructs to predict physical activity and exercise stage of change.
iAbstract Background: Surgical smoke contains hazardous chemicals and biological agents. The use of standard surgical masks alone does not provide adequate protection against surgical smokes. Hence, the application of a local exhaust ventilation system to evacuate surgical smokes is recommended. Objective: To design, construct, and evaluate a portable local exhaust ventilation system to control electrosurgery smokes. Methods: This was an experimental study carried out at Qazvin University of Medical Sciences, in 2010. A new local exhaust ventilation system containing a high efficiency air cleaner system, was designed, constructed, and evaluated in a simulated surgery process. Findings: When the distance between the system hood and the pollution sources was 5 cm and the air flow 22 cubic feet per minute, the total surgical smoke was attracted to the system hood at a velocity of 80 feet per minute. In a period of 60 minutes, the cleaning efficiency for particulate agents as well as the gasses and vapors emission was 99.77% indicating that the application of ventilation system prevented the entry of contaminants emission into the operating room. Conclusion: Based on results obtained through simulated surgery process, it was concluded that the ventilation system designed in this study completely blocked the emission of surgical smoke to air of operating room and personnel exposure.
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