Hamedan University of Medical Sciences
Journal of Occupational Hygiene Engineering
2383-3378
3
2
2016
9
1
Risk assessment of liquefied petroleum gas (LPG) storage tanks in the process industries using the Bowtie technique
1
11
FA
Mostafa
Mirzaei aliabadi
School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran
Iraj
Mohammad Fam
School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran
Omid
Kalatpour
School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran
Yousef
Babayi mesdaraghi
School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran
Introduction: LPG storage tanks contain of large volumes of flammable and pressurized gases. Release of these fluids can lead to disastrous accidents such BLEVE, fiery explosion. Therefore, identifying the causes, consequences, probabilities and scenarios of accidents using Bowtie technique, that is combination of Fault Tree Analyses (FTA) and Event Tree Analyses (ETA), is imperative and the purpose of this study.
Methods: The hazards of the mentioned in Tehran Refinery LPG tanks were identified by Fault Tree Analyses and the consequences of the top event were predicted by Event Tree Analyses. Then probabilities of the events were calculated and the accident route, from causes phase to consequences phase, was drawn by Bowtie diagram.
Results: In total, 21 events and 11 minimal cut sets with their occurrence probabilities and importance measure were determined at the left side of the Bowtie diagram. Also 9 consequences and scenarios of the top event were determined at the right side of the diagram. The occurrence probability of the top event (LPG release of spherical tanks) was calculated 3.45×10-2.
Conclusion: All factors involved in the occurrence of accidents and their consequences are showed in the Bowtie diagram. According to the obtained data, failure of cathodic protection systems and instrumentation, and overflow of tanks are included as important defects of the LPG tanks. Due to the high probability of the consequences, preventing systems such as cooling systems and Fire stop systems are required for installing in the studied unit to reduce the consequences of accidents.
Hamedan University of Medical Sciences
Journal of Occupational Hygiene Engineering
2383-3378
3
2
2016
9
1
Identification of factors affecting safety culture in Iranian thermal power plants
12
20
FA
Rahim
Goodarzi
Shazand energy generation company
Shirazeh
Arghami
Zanjan University of Medical Sciences
Mostafa
Pouyakian
Shahid Beheshti University of Medical Sciences
Introduction: safety culture is a term which is used repeatedly in the assessment of safety status of companies. The aim of present study was to investigate the parameters and factors influencing organizational safety culture in the Iranian thermal power plants industry.
Method: Triangulation approach was used for data generation in this grounded theory study. Nineteen participants from a variety of work groups at three thermal power plants of Iran (Shazand, Shahid rajaei Ghazvin and ramin Ahwaz) took part in focus group interviews, individual interviews, field observations, and focus group discussions. Thematic analysis was conducted to emerge and identify the contributing factors.
Results: The thematic analysis identified 9 sets of parameters in achieving the safety culture as follows: (1) training, briefing and competency (2) vision, leadership and commitment (3) lows, rules and work procedures (4) safety and crisis management (5) individual agents (6) Management style and organizational communication (7) participation and commitment of personnel, supervisors and middle managements. (8) Non organizational agents (9) to make available of foundations and source managements
Conclusion: The results indicated that an improvement in each parameter is necessary to achieve top safety culture. Moreover, proportionate to the conditions of each company in the periods set, should be taken for the betterment actions of safety status and accomplishing pre-determined targets.
Hamedan University of Medical Sciences
Journal of Occupational Hygiene Engineering
2383-3378
3
2
2016
9
1
Evaluation of organic solvents effects on physiological parameters of exposed people in industry
21
26
FA
Sara
Karimi Zeverdegani
School of Health, Isfahan University of Medical Sciences, Isfahan
Samira
Barakat
School of Health, Isfahan University of Medical Sciences, Isfahan
Maryam
Yazdi
School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
Introduction: One of the most common chemical exposures is organic solvents in the workplace and some of them are toxic to human health. The purpose of this study was to determine the organic solvents effect on physiological parameters of exposed people in industry.
Methods: This study was descriptive - analytical and in terms of time cross-sectional that the 50 workers were employed in the home appliance industry. The data were collected in three stages: 1) through observation and interview 2) reviewing periodic examinations of workers 3) measure the concentration of BTEX. Descriptive and analytical statistics analysis was performed with SPSS software version 20.
Results: According to the results obtained spirometry parameters in the exposed group (FEV1=89.62±10.53) is lower than the non-exposed (FEV1=97.32±8.92) while the average liver enzymes in exposed workers (SGOT= 29.56±9.49 and SGPT=38.67±17.5) was higher than non-exposed (SGOT= 17.5±6.38 and SGPT=21.11±8).
Conclusion: Long-term exposure to BTEX leads to a reduction in respiratory capacity, and increase liver enzymes. So, with proper engineering and management controls and periodic examination of such problems can be prevented in workers.
Hamedan University of Medical Sciences
Journal of Occupational Hygiene Engineering
2383-3378
3
2
2016
9
1
Assessing the explosive dust concentration and explosion risk in Shahroud high-risk industries
27
32
FA
Zahra
Moradpour
Shahroud University of Medical Sciences
Sajjad
Farhadi
Hamadan University of Medical Sciences
Sadaf
Alimohammadi
Shahroud University of Medical Sciences
Maryam
Shirian
Shahroud University of Medical Sciences
Ghasem
Hesam
Shahroud University of Medical Sciences
Introduction: Flammable dust particles when dispersed in air under certain conditions there is a risk of explosion. The aim of this study is determine the concentration of explosive dust, and the explosion risk assessment, in some a high risk industries of shahroud.
Methods: To determine the level of dust in factories investigated, sampling and determine the concentration based on the method NIOSH 0500 was done. Then to evaluate the igniter risk, risk assessment using Failure Mode Effects Analysis (FMEA) was conducted. The main sources of possible secondary explosion were determined by observation and interviews with managers and supervisors.
Results: Results of the survey the concentration of explosive dust in industries showed the most explosive dust generation, was related to the PVC industry with a concentration of 43 ± 74 mg per cubic meter. FMEA risk assessments results also showed that the cargo handling equipment, drying, cutting and drilling equipment, motors and switchgear lightning’s, are the most risky equipment in creating sparks and ignition. Also the study showed, silos with their high storage capacity can be the most likely sources of secondary explosions.
Conclusion: This study showed that concentration of explosive dust to a minimum explosive concentration is very low. But given the vast resources and great sources of ignition powder storage products that exist, pay attention to dust explosions in some of these industries is very important.
Hamedan University of Medical Sciences
Journal of Occupational Hygiene Engineering
2383-3378
3
2
2016
9
1
Ergonomics intervention to reduce musculoskeletal disorders: case study in cement company production
33
40
FA
Abbas
Moradi
Rashid
Haidari
Majid
Motamedzade
Javad
Faradmal
Mohammad
Babamiri
Introduction:Musculoskeletal Disorders (MSDs) are one of the most important factors occupational injuries and disabilities in workplaces. The aim of the persent study was ergonomics intervention to reducemusculoskeletal disorders.
Methods: This interventional study was conduct on 126 preservation and maintenance workers in cement company by classfication sampling. The Nordic Musculoskeletal Disorders Questionnaire, QEC and Ergonomics Checkpoint methods were used to collected data before and after the interventions. The interventional program include practical and easy to implment solutions for improvement safety,health and work conditions, workers trainig, selective and corrective exer Data were analyzed by Mcnemar test using SPSS_22 software.
Result: Data analysis showed significant differences(P_value<0.001) between prevalnce of disorders during one week before interventions. for lower back,back and were 62.70%, 60.32% and after intervention were reduce to 46.03% and 43.65%.
Conclusion: Acoording to QEC method, 83 maintenance workers ( 65.87%) were at high risk and prevalence of lower back and knee was high that applying of simple and inexpensive solutions, participatory solutions of Ergonomics Checkpoint andselective corrective exerciselead to musculoskeletal disorders reduction.
Hamedan University of Medical Sciences
Journal of Occupational Hygiene Engineering
2383-3378
3
2
2016
9
1
Developed a needle trap device with PDMS sorbent for microextraction of toluene and methyl ethyl ketone from aquatic samples using dynamic headspace
41
46
FA
Sara
Karimi Zeverdegani
Department of Occupational Health Engineering, School of Public Health, Isfahan University of Medical Sciences, Isfahan, Iran
Abdulrahman
Bahrami
Department of Occupational health Engineering , School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran
Masoud
Rismanchian
Department of Occupational Health Engineering, School of Public Health, Isfahan University of Medical Sciences, Isfahan, Iran
Farshid
Ghorbani Shahna
Department of Occupational health Engineering , School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran
Introduction:
Due to the widespread use of toxic chemicals in most workplaces that can lead to toxic effects on human, various chemical extraction technique have been defined for analysis these toxic substances in air, water and biological samples. The purpose of this research is extraction of toluene and methyl ethyl ketone from aquatic samples with needle trap device and one commercial sorbent.
Methods:
In this research, needle trap device was used to extraction of toluene and methyl ethyl ketone in aquatic samples, so needles(size 20) were packed with PDMS and extraction was done with dynamic headspace needle trap device. Gas chromatography with - flame ionization detector was used to analysis and optimized extraction of two substances were obtained.
Results:
Results show that the optimum temperature and time extraction was similar for toluene and methyl ethyl ketone (30 ° C, 30 min), but the reproducibility of results and calibration curve that obtained for toluene was better than methyl ethyl ketone.
Conclusion:
Needle trap technique is inexpensive, sensitive and portable also this method has good recovery to extract small amounts of toluene and methyl ethyketon from aquatic samples with polydimethylsiloxane.
Hamedan University of Medical Sciences
Journal of Occupational Hygiene Engineering
2383-3378
3
2
2016
9
1
Systematic analysis of a decade of occupational health research in Iran
47
55
FA
Aram
Tirgar
Seyed Ehsan
Samaei
Introduction:
In view of the increasing attention to the health of the workforce and the other hand the increase in scientific outputs in format of scientific and research papers, the aim of this study was to monitor the status of technical articles of Iranian journals in the field of health workforce.
Methods:
This retrospective cross-sectional study was conducted for a period of ten years (2005-2015) in the specialized field occupational health journals. The data based on content analysis method with researcher-made checklist and using by census articles were collected.
Results:
the extracted data, from 927 article from 5 specialized journals in period of ten years, was represent the growing trend in publication of Persian and English articles. Most research had been done respectively in physical and mental health scope. According to the type of harmful factors, Ergonomic factors with 24.27 percent, has been allocated to itself the largest portion of articles and research. Only 11.54 percent of reviewed articles was interventional studies. Also, cohort studies was not found among articles.
Conclusion:
The findings of this study which is the Scientometrics type, represent the imbalance in health workforce researches. So that hazardous agents such as ergonomic factors is strong emphasis and some health aspects such as public health is neglected. According to current situation, setting national priorities in order to balance the distribution of health force researches is necessary.
Hamedan University of Medical Sciences
Journal of Occupational Hygiene Engineering
2383-3378
3
2
2016
9
1
Ergonomic evaluation of pressurized irrigation equipment factotry operators using an easy posture assessment
56
63
FA
Sajjad
Deyhim
Hamadan University of Medical Sciences
Morteza
Babaei
Hamadan University of Medical Sciences
Majid
Motamedzade
Hamadan University of Medical Sciences
introduction: One of the most common causes of occupational injuries in industrialized and developing countries is musculoskeletal disorders Determining the risk factors of musculoskeletal disorders can be helpful choosing the right method for interventions and detailed studies. This study aimed to evaluate the ergonomic risk factors in operators of pressurized irrigation equipment factory.
Materials and Methods: This cross-sectional study was conducted in a pressurized irrigation equipment manufacturing company. In this study, a new method based on observation was used to evaluate the ergonomic aspects of operator's activity. In order to assign tasks and sub-tasks, direct observation and video recording equipment were used. Ergonomic assessment was carried out on all sub-tasks identified. then, the criticality of the task determined.
Results: Among the tasks identified 53 very critical posture 61 critical and 82 low critical posture was determined. Ergonomic point in the ball valve production line was 0.6 and 0.68 respectively for tow operator. For drop valve and automatic valve production line's ergonomic point was 0.52 and 0.67 respectively.
Conclusion: According to the results, posture analysis method used in this study is easy and accurate. The advantage of this method is 14 ergonomic domaines that covered whole body and time fragment of each task. Findings of previous studies showed good correlation between results from this method and OCRA method.
In this study, The most critical posture was related to operator's wrist, so it is recommended that control measures on wrist posture correction should be considered.