Journal of Health and Safety at Work

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Introduction: This study was conducted to assess noise pollution in one of thepetrochemical complex andtakepractical measures to reduce it. Thecompanyis located in site 4 of Mahshahr Special Economic Zone.

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Method and Materials: In the first phase of the research, environmental noise was measured to determine the noise levelsin the different sections of the plant and also identify the main sound sources.Then,using the basic acoustic knowledge, aformulahasbeenproposedasan indexof noise control priority to select one section of the plant as the first priority forcontrolling noise. The main soundsource of the selected section wasknownby referring to noise maps and contours and finally its acoustic properties were analyzed.

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Results: The results showed that safety caution and danger areasof the plant under study were 16.7%, 74.5% and 8.8% respectively and a major part of the danger zone (about 54%) was related to unit Air. Noise level in 24 percent of the caution zone ranged from80 to 85 dBA and alsoitwas above 90 dBA in 33.4% of danger areas.

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Conclusion: Compressionsectionwhich was located in unit Air was knownas first priority based on Noise Control Priority Index.Dryer machineswere the main sound source in this section.

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Introduction: Noise is one of the most common health hazards at the workplaces that can cause not only somatic problems, but also adversely affect mental health. The aim of this study was to investigate and evaluate occupational noise exposure and noise annoyance in one of the petrochemical companies.

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Material and Method: The study population included 47 people working in Administrative and Manufacturing parts of the petrochemical company. First, dosimetry of production workers and noise frequency analysis of Administrative employees were performed. Then, self-report questionnaire for the assessment of noise annoyance at workplace was completed by the subjects. The questionnaire consisted of three parts: scoring of the noise intensity in the workplace, scoring of the noise annoyance in the workplace and determining the feelings and emotions (e.g. fatigue, sleepiness, and concentration problems) that experienced by subjects during the working day.

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Result: The results of noise dosimetry measurements showed that mean eight hour equivalent continuous A-weighted sound pressure level was 86.13 dBA. According to the frequency analysis of office rooms, mean noise level and Preferred Noise-Criteria (PNC) was 69.4 dBA and 62 dB, respectively. The findings of our analysis revealed that 17.9% of administrative staff and 63.2% of manufacturing workers assigned “very high” score to the noise intensity in the workplace. The annoyance score was obtained “very annoyed” by 10% of employees of office section and 42% of manufacturing workers. For noise-related complaints and sensations defined by subjects, 49% of administrative staff and 60% of manufacturing workers marked the “sometimes” and “more” item of the questionary.

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Conclusion: Based on the obtained results of investigating the noise level (objective exposure) as well as the noise annoyance (subjective exposure) at the studied company, it is necessary to adopt the management –technical noise reduction measures at manufacturing sectors as the personal noise exposure and environmental noise exposure and also noise personal exposure of administrative staff can be decreased.

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Introduction: Safety signs provide information,related to hazards or dangers in the industry,in form of instructions. These signs are effective as long as they are designed in accordance with principles of ergonomics and design cognitive features. The purpose of this present research was to study the relationship between cognitive features of signs and ability to guess, and to develop the relevant regression model.

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Materials and methods: This descriptive cross-sectional study was carried out on 100 employees in a petrochemical industry complex. A three part questionnaire was used to collect required data while first part of the questionnaire dealt with demographic information, second part included cognitive features of signs designand the third part proceeded on testing the ability to guess. Then, a regression model was developed to determine the relationship between cognitive features, and the ability to guess.

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Results: Mean and standard deviation obtained for the ability to guess the total study signs were 63.73 and 4.36, respectively. The feature of “familiarity” obtained the lowest possible score (49.15). The “semantic closeness” (β=0/390) and “meaningfulness” (β=0/369) had the highest correlation with the ability to guess safety signs.

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Conclusion: According to results of this study, use of principles of ergonomic design of signs and training are necessary to promote the ability to guess the safety signs to the minimum available standards. Therefore, it is possible to balance cognitive features especially “familiarity”, with the lowest score, and “meaningfulness” and “semantic closeness”, with the highest influential relationship with the ability to guess of signs. The developed regression model for this industry can be used to predict the ability to guess of safety signs in future studies

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Introduction: Work-related accidents may cause damage to people, environment and lead to waste of time and money. Health, Safety and Environment Management System has been developed in order to reduce accidents. This study aimed to investigate the effect of implementation of this system on reduction of the accidents and its consequences and also on the safety performance indices in Kermanshah Petrochemical Company.

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Material and Method: In this study, records of accidents were collected by OSHA incident report form 301 over 4 years. Following, the mean annual accidents and its consequences and safety performance indices were calculated and reported. Then, using statistical analysis, the impacts of two years implementation of this system on the accidents and its consequences and safety performance indices were evaluated.

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Result: The results showed that the implementation of HSE system was significantly correlated with Frequency Severity Indicator, Accident Severity Rate, lost days, minor accidents and total incidents (P-value <0.05). Moreover, the values of these variables have been reduced after implementation of this system. However, the system did not influence the Accident Frequency Rate and disabling accidents (P-value> 0.05).

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Conclusion: The implementation of Health, Safety and the Environment Management System caused a reduction in accidents and its consequences and most of the safety performance indices in the entire process cycle of Kermanshah Petrochemical Company. Overall, safety condition has been improved considerably.

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Introduction: Nowadays, human error is one of the main causes of incidents in the industry. One of the vital characteristics of modern industries is that the precise control of key parts of the process is performed by operators from central control rooms, so an error by the control room staff can be disastrous. The present study is aimed at identifying and evaluating human errors in the control room of the petrochemical industry.  
Material and Methods: This is a descriptive-analytic case study that was conducted in a control room of the petrochemical industry. In this research, firstly by using hierarchical task analysis (HTA), the tasks in the control room were identified and analyzed. Then, using the extended CREAM method, possible human errors were identified, their cognitive category was determined, and their probabilities were calculated using a new approach based on BN.
Results: The results of the study showed that the most prevalent control modes for the Boardman and the senior board man were strategic and scrambled modes with error probabilities of 0.136 and 0.171, respectively.
Conclusion: According to the results obtained in the modeling section, BN can be proposed as an approach with high processing accuracy and also high accuracy in modeling human errors and problems with high input parameters affecting the output parameter.

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Introduction: Hazard Identification, risk assessment and management have an important role in reducing potential risks in industrial settings. This research was done with the aim of identifying the hazard and evaluating HSE risks and providing a HSE management program for the Urea Unit of Shiraz Petrochemical Complex.
Method: Firstly, hazard identification and qualitative risk assessment was done using FMEA technique and risky units were identified. Then, main events were identified and analysed as inputs of the Bow-Tie method. By identifying the strength, weakness, opportunity and threat factors, ranking and weighting them using the ANP method and Super Decisions software, a SWOT matrix was prepared and HSE management strategies were extracted.
Findings: The results showed that chemical leakage, falling from height and slipping were the most important incidents, and defect of control equipment, lack of attention to instructions, non-compliance with safety principles and human error were causes of these events. Also, ranking of weaknesses, strengths, opportunities and threats were 0.58, 0.2, 0.16 and 0.05, respectively.
Conclusion: Organizational opportunities with a weight of 0.124 were 4.8% higher than threats with a weight of 0.076. This shows that the company had a good situation in terms of achieving its goals.

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Introduction: Styrene (C₆H₅CH=CH₂) is known as one of the volatile organic substances produced or used in petrochemical industries. Exposure to this chemical compound can thus lead to respiratory diseases. Therefore, this study aimed to evaluate occupational exposure to styrene vapor and to determine the risks of its health consequences in petrochemical industry workers through a quantitative method.
Material and Methods: In this descriptive cross-sectional study, a total number of 150 samples from 50 employees were studied using the National Institute for Occupational Safety and Health (NIOSH) 1501 method. The samples were then analyzed by the Varian CP-3800 chromatograph. Upon determining exposure to styrene vapor, the risk assessment of the health consequences of styrene in the workers in the given industry was evaluated via the relationships established by the United States Environmental Protection Agency (US/EPA).
Results: According to the results, the polybutadiene latex unit (PBL) was observed with the highest average exposure (0.44 mg.(kg-day)-1). Therefore, the top predictors of carcinogenic and non-carcinogenic risks were valued 0.44 and 0.71, respectively, for the PBL unit. Given the lowest average exposure (0.0012 mg.(kg-day)-1) in the drying unit, the prediction revealed the most moderate carcinogenic (0.1 ×10-5) and non-carcinogenic risks (2×10-3) for the same employees.
Conclusion: Overall, the health risk was higher than the permissible limit in the petrochemical industry studied, especially in the PBL unit. Therefore, it is recommended to make use of artificial ventilation, notably the local type, in addition to the natural ones.