مجله مهندسی بهداشت حرفه ای
سال دوم شماره 1 (بهار 1394)

Mercury is a toxic and bio-accumulative pollutant that has adverse effects on environmental and human health. There have been a number of attempts to regulate mercury emissions to the atmosphere. Silver nanoparticles are a number of materials that have highly potential to absorb mercury and formation of mercury amalgam. The aim of this study is removal of mercury vapors in the dental clinic using a n a ir cleaning system based on silver nanoparticles. In this study, silver nanoparticles coated on the bed of foam and chemical and structural properties were determined using a number of methods such as UV-VIS-NIR spectroscopy and Scanning Electron Microscope (SEM) connected the X-ray Emission Spectroscopy Energy (EDS). The a ir cleaning system efficiency to remove of the mercury vapor in simulated conditions in the laboratory and real conditions in the dental clinic were measured by Cold Vapor Atomic Absorption Spectroscopy (CVAAS). The images of SEM, showed that average size of silver nanoparticles in colloidal solution was ∼ 30 nm and distribution of silver nanoparticles coated on foam was good. EDS spectrum confirmed the presence of silver nanoparticles coated on foam. The significantly difference observed between the concentration of mercury vapor in the off state (9.43 ± 0.342 μg.m-3) and on state (0.51 ± 0.031μg.m-3) of the a ir cleaning system. The mercury vapor removal efficiency of the a ir cleaning system was calculated 95%. The air cleaning system based on foam coated by silver nanoparticles, undertaken to provide the advantages such as use facilitating, highly efficient operational capacity and cost effective, have highly sufficiency to remove mercury vapor from dental clinics.

Currently, work-related musculoskeletal disorders are one of the highest concerns of Occupational health. The purpose of this study was to evaluate the risk of musculoskeletal disorders by assessment of repetitive task (ART) and implementation of ergonomic intervention programs in a manufacturing company. In this study, 60 workers were randomly selected from production line. The data was collected by using the demographic questionnaire and ART technique. Intervention has been done on 39 cases. Data was analyzed by using SPSS. Initial evaluation showed that in cases, (21.7%) were at low level of risk, (48/3%) at average level of risk, and (30%) were at high risk. After intervention, the reassessment showed that the frequency of the low-risk levels before the intervention (30.70%) to (53.85%) increase. in the average risk level (64.10%) changed to (43.59 %) and high risk (5.2%) changed to (2.56).A significant difference was observed in the intervention(Pvalue< 0.05), by Paired t-test. The initial evaluation of eergonomic risks are not at acceptable level in the most activities and most people were at moderate level of risk. Since, many workers in the assembling industry suffer from musculoskeletal disorders. With Engineering and management low cost control measures could reduce level of risk.

Background­ and Burnout is one of the causes of reduced job performance and productivity, this syndrome in jobs who deal directly with people are more than other professions may be viewed. This study was conducted to investigate the relationship between demographic variables, efficiency, and staff burnout in a hospital. In this descriptive-analytical study all 100 employees of the hospital were evaluated. People by demographic information, Maslach Burnout questionnaire (MBI) and productivity questionnaire were studied. Data analysis was performed using descriptive and inferential statistics. Findings showed there was a significant correlation between the frequency of emotional exhaustion and reduced personal performance scale (the scale of burnout) with productivity. Burnout in emotional exhaustion scale for 41 to 50 years and reduction of operation scale for 20 to 30 years old had the highest score. Metamorphosis and efficiency in terms of significant differences between the study found, and those with a bachelor's degree and those with postgraduate highest grade metamorphic and more than had the highest productivity. Respondents with less than 8 hours daily working hours are significantly higher productivity. Metamorphosis in nurses has higher scale scores. Productivity in anesthesia was significantly higher than other occupational groups. According to different levels of burnout and its damaging effects on the health of employees, lower productivity and quality of patient care, while more research on the causes of light, especially in institutional factors. It is suggested to adopt the methods of adjusting and preventive action to reduce this phenomenon.

Noise is a widespread physical agent and although is a most risk factors in workplaces that workers of health to exposed. Thus, different actions is done for reduce exposure to it in work places, which one of them is use of hearing protection devices. The use of hearing protection devices with approach risk perception of noise induced hearing loss in several manufacturing industry This study was Cross-sectional study and done in five industrial unit with a sound pressure level more of 85 dB-A with the participation of 340 workers. To collect data, individual risk perception and self-investigator questionnaires were used. After collecting data, statistical analysis including Cronbach's alpha and regression were used to analyze the data. Range use of hearing protection devices during shifts work by workers, respectively equal to: 50.4% sometimes, 31.58% never and 18.2% at all times. Also, results indicate significant differences between individual differences and hearing protection devices. Results of this study showed that individual risk perception as an important factor, can do a significant role in predicting the behavior of personals in the use of hearing protection devices, which should be considered in any design and implementation of hearing protection program.

Musculoskeletal pain is an important subject in the world and it is a one of the greatest problem of occupational health in developing countries. Also, the musculoskeletal pain is common in offices due to prolonged awkward postures. On the other hand, this disorder can reduce the employee's job satisfaction and productivity of organization. The aim of this study is to determine the prevalence of musculoskeletal disorders and job satisfaction in a gas company. In this cross sectional study, all administrative staffs of a gas company (142 Persons) were participated. Data was collected based on Nordic musculoskeletal questionnaire and the Minnesota Job Satisfaction Questionnaire. Statistical Analysis of collected data was performed using SPSS 13 by using chi-square test. The highest complaints of musculoskeletal pains during the past year were respectively, 52 percent for neck, 35.2 percent for low back, 33.8 percent for upper back. 40.4 percent of employees have expressed a high level of job satisfaction. However, statistical tests showed respectively a significant relation between teaching about proper posture and job satisfaction (pvalue= 0.023), and also shoulder pain and job satisfaction (pvalue=0.02). Regarding to high incidence of musculoskeletal disorders and expressed 50.4 percent average job satisfaction by employees, it seems intervention to ergonomically improve workstations is necessary.

Biological adsorbents under undesirable conditions have not suitable performance. Based on this problem, the using of the molecular imprinted polymers (MIPs) have been proposed. This study was conducted to adsorption of trace triazinic pesticides with synthesis and optimization of molecular imprinted polymers as a novel solid phase extraction (MISPE). In this study, atrazine and ametrin polymer and blank were synthesized by central composite design method and optimized based on the amount of functional monomer, template, cross linker, initiator, solvents and polymerization temperature. Then the appropriate cartridge was selected and SPE procedure based on the concentration, sample volume, flow rate and sample pH were optimized with response surface methodology. Concentration factor and as well as reusability of the cartridges were examined finally. Based on the obtained results, for ametryn and atrazine, optimized temperature was calculated equals to 40.86 °c, 6.41 and 5.03 ml for solvent, 27.070 and 21.32 for crosslinker, 2.03 and 2.27 mmol of initiator, 5.41 and 4.73 mmol for monomer and 1.204 and 0.811 for template respectively. Based on the optimization results of the molecular imprinted solid phase extraction, it was revealed that there are recovery rate over 90 percent for the drinking water and urine as spike. The results showed that central composite design can be used as a general tool for polymer synthesis and optimization of molecular imprinted solid phase extraction. Polymers according to theirs high-performance and selectivity also can assume an important role in monitoring the work environment.

Human errors play a significant role in accident. One of the important operations in mines which were susceptible to human error, is blasting operations. The aim of this study is identification and assessment of human errors in blasting operations in iron ore mine. Current Study is a qualitative research study in order to identify and assessment human error in a mine blasting operations. With direct observation of activities and documents, sub tasks were selected and analyzed by hierarchical analysis Job (HTA). The results were presented in the form of HTA charts. Types of possible human errors were detected and by using the SHERPA technique were surveyed. Appropriate prevention solutions were then proposed for reducing the risk of errors. The results showed, from total of 42 identified errors, predicted the unacceptable risks are 0.11, adverse risks are 0.42, acceptable risks with revision are 0.4 and accepted without revision are 0.04. Moreover, percentage types of human errors were included practical errors (0.55) and recovery errors (0.14), checking error (0.21), selection errors (0.6) and communication errors (0.016). The highest percentage of errors is practical and the lowest percentage of errors is of communication error. To reduce the occurrence of any identified error and limiting the consequences of their, appropriate control measures in the design of checklist, the use of appropriate personal protective equipment, the use of systems Tag Out- Lock Out, efficient education laws and guidelines are effective.

Background­ and Research has consistently shown that air quality; personal factors and work related factors were the most effective parameters for sick building syndrome. Several epidemiological studies have been carried out to show the prevalence of the sick building syndrome among the office workers but less attention has been paid to the relation of the sick building syndrome and the environmental parameters. In this work، the relationship between sick building symptoms and indoor environmental factors of two office buildings were studied. In this cross- sectional study، the sick building symptoms among two office building workers of Petroleum Industry Health Organization were examined. For this purpose، a validated questionnaire was used to determine the prevalence of the sick building syndromes and the relationship between personal and environmental factors. Meantime، indoor environmental factors including noise، light، humidity، air velocity، temperature and CO2 concentration were measured with appropriate calibrated instrumentations. The results revealed that there is a significant relationship between CO2 concentration as an air quality factor and some sick building symptoms including nausea، headache، nasal irritation، shortness of breath and dry throat. A significant relationship (P-Value < 0. 05) was determined between the noise exposure and headache as well as dizziness. The light intensity had a significant impact (P-Value < 0. 05) on dry skin، eye pain and malaise. Sick building symptoms among the women were higher than men. Environmental factors and indoor air quality had major impact on sick building symptoms in office buildings.