پیمان دادکانی

Today, gas industries mainly include extraction, processing, transmission and consumption. After extraction, natural gas is directed to the gas treatment unit by the collection network. Gas pressure drop is done in gas pressure reduction stations, so pressure reduction station, feeding network and gas distribution network play an important role as process units of gas supply companies. The use of risk assessment techniques in this area to identify high risk cases will allow optimal control of the system. The analysis of major accidents in these stations shows that a large part of the damage and damages of the accidents and the possibility of their occurrence are not only preventable but also predictable, of course, if measures such as identifying the root causes and final consequences and controlling them are carried out in time. Analysis and risk studies are one of the most necessary steps to increase the level of safety in these stations. The complexity and expansion of chemical and process industries lead to high safety risks and disasters in the world. Some of these tragic events are Fizin, Mexico City, Bhopal (India), Piper Alpha (UK), liquid fuel explosion (North Sea) or Chernobyl (Russia). Transportation of hazardous materials is a major source of hazards that threaten many industries as well as the public. These networks of hazardous material transmission lines are distributed among many industries and their customers, including the general population. Although the transportation of hazardous materials by pipelines seems safe, it still involves safety issues. Although the frequency of pipeline accidents is low, their high potential for consequences can affect the low frequency. Accident databases show that pipelines carrying hazardous materials are just as dangerous as refinery facilities. Pipeline industry It has experienced at least 8 major explosions and more than 55 deaths in 2014 alone. Pipelines are placed in areas that are not normally controlled. In addition, pipelines passing through high-risk areas such as congested areas make the situation even more dangerous. Therefore, high potential consequences, lack of control and passing through high-risk areas have made pipelines a serious source of destructive risks. Risk management should be measured according to the organization's policy and risk evaluation approved by the senior management and carried out through the method approved by the organization. According to the process safety management system, it is suggested to identify and evaluate process risks in the stages of installation, pre-commissioning, commissioning and operation, and in case of making any changes in the process, technology and equipment, document the changes in order to prevent the risks. Prepared from the changes. Some of the risks caused by changes are very small and have no harmful effects, so some others leave harmful effects and irreparable damages, for which it is necessary to take the necessary measures. By comparing the scenarios of accidents in different countries without considering their development status, it shows the existence of some common factors between the accidents that took place. The analysis of these incidents has factors such as human error, too much trust in equipment, design problems in operational units and lack of safety, health and environment units. The most important factor in system safety and risk management is the identification and reduction of risk potentials. In order to successfully control and control the risks, you must have a proper understanding of the risks and how to deal with them and how to identify them. In recent years, the lack of safety has become one of the most important issues and problems in the design and operation of operational units. First, due to the complexity of most processes in modern operating units, there are fundamental changes in control strategies and numerous improvements in process capabilities, all of which lead to an increase in operational problems, and second, due to the accidents that we witness every year around the world and cause loss of life, problems Environmental and loss are produced. It is possible to improve the safety of operational units in the stages of design and operation, if the necessary attention is paid to the analysis and identification of process risks. Risk of injury is the risk that occurs to specific individuals or groups exposed to it in any system or process. Accident analysis points to various factors, including human errors, over-reliance on machine safety, plant design problems, lack of preparation to face and deal with critical situations, and non-compliance with HSE rules.The method used in this research is evaluation-analytical. In the current research, in order to compile the theoretical literature, the background of the research and to identify some research criteria, reliable books and researches conducted inside and outside the country, such as reliable domestic and foreign magazines and articles related to the research topic, were used. Some of the domestic publications used can be referred to as articles indexed in Elsevier scientific database, domestic research journals, and Sulica scientific database. By using the fuzzy-Delphi approach, by preparing a questionnaire and interviewing experts, these factors were screened and reduced to the main factors, and at the end, another questionnaire was prepared for pairwise comparisons of the identified factors, whose values were analyzed using the HAZOP method, and the influencing factors. and were identified as effective. HAZOP is a qualitative, systematic, creative and group method that is very easy to learn and is an effective way to identify hazards and system performance problems by determining their effects. The implementation of HAZOP is as follows:1. Knowledge and general understanding of the system2. Dividing the system into functional nodes3. Identify deviations in each node using the keyword4. Determine the main keywords: pressure, temperature, flow, etc5. Use of secondary keywords: not, more than, less than, as well as etc6. Estimating the probability and consequences of deviations7. Determining the risk level of risks using the risk matrix8. Define controls to reduce risksTo perform the HAZOP method, a team of specialists who have sufficient knowledge of the conditions and risks of the gas station must first be formed. The first step is to fully understand the system and process of the gas station, what equipment the station includes, with what features and functions. In the next step, this system is divided into nodes based on the function of each equipment. These nodes include scrubber filter, separator filter, dry filter, regulator and safety valve. After identifying the deviations in each of the nodes, the risks of each node are determined using the main keywords and secondary keywords. Using the severity of incidents in Table No. 1, the probability of incidents in Table No. 2 of the risk matrix is determined according to Table No. 3. Finally, based on the level of risk and risks of deviations in each of the nodes, controls have been recommended.Out of 12 identified risks, 9 risks were in the acceptable risk group and 3 risks were in the undesirable risk group. This result indicates the favorable situation for the existing protections of Bampur gas station. The risk number of 8 for 2 deviations of separator filter and dry filter nodes is due to the structure of these two nodes, which has a filter valve in addition to the flange. Despite the favorable conditions of the station, due to the harmful consequences of deviations, all safety requirements must be met, therefore, safety recommendations including periodic inspection, personnel training, and timely replacement of gaskets and fasteners have been emphasized. From similar researches, we can refer to the research of Donjo and his colleagues in 2010. This article is entitled to collect the literature related to the HAZOP method. In this research, Donjo collected the literature related to the HAZOP method from books, guidelines, standards, large magazines and conferences with the purpose of classification and conducted research over the years to use this method. In the industries discussed, the method and results of the current research are somewhat in line with the reviewed article. In another research in the field, Alfredo improved the conventional HAZOP analysis through the fuzzy multi-attribute HAZOP technique. The results of the research indicate the identification of critical risks in the subsystem, which showed the sensitivity analysis of the reliability and strength of the final rating. The results of this analysis support preventive maintenance by identifying critical monitored points when scaling up biological biogas upgrading processes, which the results of Donjo's research partially overlap with the results obtained in the present study.

Extensive construction projects such as dam construction, road construction, water transfer, land leveling, and railways are active in the country, and in all these projects, manpower and equipment play an important and decisive role. The purpose of this research is to identify the ergonomic hazards of the office environment and the activity of machinery in the workshop of section 6B of the Chabahar-Zahedan railway project. In order to collect information, questionnaires were compiled and distributed among workshop experts who were a group of senior managers and middle managers of the workshop. After completing the questionnaire, the obtained data were analyzed using the FMEA technique, and three indicators of probability, severity and probability of risk detection and finally the rank of each risk were determined. The results of the risk assessment of the office environment, including the technical office, HSE, human resources and the warehouse, show 17 ergonomic risks in the office environment, the highest risk is related to the warehouse unit with a risk rating of 196 and the risk of moving equipment. Examining the risks of machinery activity shows 18 risks related to excavators, dumpers, rollers, graders and loaders. The highest risk rating is related to the excavator with a risk rating of 192 with the risk of rock fall from the trench. All identified risks are placed in the group of risks with a low risk rating.The trend of accidents in industrial environments has also increased due to the increase in industrial activities, the development of technology and the increase in the use of machines. In traditional systems, investigating the causes of accidents after the occurrence of accidents, irreparable damage is determined, in other words, system or process defects are determined after the accident. Today, due to the existence of different methods of hazard identification and risk assessment, it is possible to determine critical and accident-prone points before an accident occurs and take necessary measures to prevent accidents and control measures. To identify and prioritize risks, the method of risk identification and risk assessment, which is a structured method, can be used. Risk assessment is a logical method that measures the quantitative and qualitative assessment of risks and the investigation of the potential consequences of possible incidents on people, materials, equipment and the environment. In fact, in this way, the effectiveness of the existing control methods is identified and valuable data is provided for making decisions in the field of reducing risks and hazards, improving control systems and planning for them. The information obtained from the risk assessment has three basic uses, which include prioritizing the degree of importance of risks in order to allocate risks for limited financial, technical and human resources in eliminating defects and improving conditions, determining points that need optimization in terms of occupational safety and health, and Their risk should be reduced to the minimum tolerable level, and finally, the content of classic trainings should be determined while working in the field of occupational health and safety. Among the different methods for risk assessment, there is a useful risk assessment method that, in addition to being simple, should be appropriate to the nature of activities, processes, culture, and other characteristics of the organization in question. Among the existing risk assessment methods, there is the method of analysis of failure modes and their effects (FMEA).The present research is an evaluation-analytical method; And it is survey type. To collect and compile information, the method of library studies and compiling a questionnaire was used. Questionnaires were distributed and completed among 20 senior personnel of the workshop, including the workshop manager, deputy workshop manager, machinery manager, HSE manager and other unit managers located in the Chabahar-Zahedan railway workshop complex, workshop 6B. The accuracy and reliability of the questionnaire developed in this research was confirmed by the experts of the workshop, and the reliability of the questionnaire with the analysis done in SPSS software and the use of Cronbach's alpha coefficient to measure the reliability was about 0.85. It has been stated that the evidence of optimal and reliable conditions was compiled with a questionnaire. After completing the questionnaire and data analysis, the data was analyzed using the FMEA technique, and three indicators of probability, severity, and probability of risk detection were determined, and finally, the rank of each risk was determined. Then, the ergonomic risks of office personnel and the risks related to the operation of machines were compared. Analyze the identified hazards by considering the risk factors of occurrence (O), severity (S) and detection (D). The main purpose of FMEA is to allow analysts to identify the failure modes of a system, design, process, product or Prioritize services to allocate limited resources to high-risk cases.The prioritization of failure modes in FMEA is determined through the risk priority number (RPN), which is the coefficient of risk factors D, S, and O for each risk, where O stands for the probability of occurrence, S is the severity of the risk, and D is the probability of detecting the risk. and RPN represents the risk priority number. The three risk factors are presented in Tables 1. As mentioned, the RPN number is obtained from the product of the three components of risk probability, risk intensity and risk detection capability according to formula number 1. According to the obtained risk number formula, they are divided into three levels of low risk, risks 1-300, medium risks including risks 301-600, and high risks with RPN 601-1000. The overall flowchart of the study is shown in Figure 2. The steps of the research are:1. Distribution of questionnaires among experts2. Forming a working group of data analysis experts3. Using FMEA technique for risk assessment4. Comparison of ergonomic risks and machines The purpose of this research was to identify the risks in the two fields of ergonomics and machines activity using the FMEA method. The obtained results indicate that 17 identified ergonomic risks have a higher probability of risk and 18 risks related to the activity of machines have a higher risk intensity. The highest risk rating in the two evaluation cases belongs to the risk of moving equipment and tools of ergonomic activity in the warehouse with a risk number of 196 and the lowest risk rating also belongs to ergonomic activities and the potential risk of inappropriate lighting with a risk number of 60. A total of 35 identified risks are in the group of risks with a low risk rating, which is evidenced by the low number of workshop accidents. At the end, suggestions on control measures for ergonomic risks and machinery activity are presented in Table 4.

Risks in various industries including oil, gas, petrochemical and power plants can have irreparable consequences. Power plants are always exposed to many risks due to the use of flammable materials as fuel and various activities, therefore identifying risks is necessary to prevent accidents. The purpose of this research is to investigate the most important potential risks in the activities of Bampur Gas Power Plant. In this research, by using the FMEA method, the risk assessment of site visit activities, loading and repairs, cutting and working with millstones has been done. After that, hierarchical analysis of criteria and options was done using Waspas software, and finally, the obtained options were prioritized. The obtained results indicated the identification of 16 risk cases, and the hierarchical analysis of the options with the Waspas software showed that the highest preference was given to the option of working with a grinding stone and then visiting the site with a weight of 0.411 and 0.388, and the lowest weight was given to the activity Repairs amount to 0.340.The failure of a system or the occurrence of accidents due to the use of complex systems in today's society can cause disturbances at different levels and even be considered as a threat to society and the environment. That's why everyone is looking for a secure system with low risk probability. This is where the term risk appears to indicate the probability of occurrence and its severity. It is the risk outcome that determines what damage will be caused to the system by the occurrence of each hazard and what environmental consequences it will have afterwards. Based on the definition, risk is defined as the degree of probability and severity of the occurrence of the risk and its consequences. The World Standard Organization's definition of risk includes the possibility of an accident and its consequences. According to the report of the International Organization (ILO), 2 million occupational accidents leading to death and 266 million non-fatal accidents occur every year, the economic consequences of which are equal to 4% of the gross national product. Risk assessment and management is one of the important pillars of HSE management. Organizations must constantly evaluate risks related to HSE. In order to identify specific risks, assess and control risks to an acceptable level, activities must be evaluated. The use of risk assessment as a systematic and organized method to identify risks and risk assessment for risk ranking is to reduce the risk to an acceptable level. Risk assessment has different methods with a range of quantitative and qualitative methods. Due to the importance of identifying and prioritizing the main risks, there are many methods to perform these tasks, and the failure mode and effect analysis method (FMEA) is one of these methods. The FMEA method is one of the main techniques used to identify and analyze relevant risks that are effective in improving safety. In this method, the indicators of a given system are basically used for qualitative analysis. Systems or subsystems of an assembly are examined to assess the effects of potential faults on other system components to identify potential faults. In addition to determining the risk levels of various processes, risk assessment enables us to make appropriate decisions to take the necessary measures to protect people. Safety, because of its general and universal value, all cultures should do their best to maintain and implement it. Risk, safety and its strategies are necessary to implement comprehensive risk and safety management among other countries and organizations. The information obtained from the risk assessment has three basic applications, including determining the points that need to be optimized in terms of occupational safety and health in order to reduce their risk to an acceptable risk, prioritizing the degree of importance of risks to allocate various limited resources, including financial, technical and human resources, it is in removing defects and improving conditions and finally determining the content of on-the-job training in the field of occupational health and safety. Among the existing methods, the method of analysis of failure modes and its effects (FMEA) is a method that has recently been widely used in order to investigate the potential of defects in various products, processes, designs and services. This method analyzes the components of the system and relates the conditions of the components to the conditions of the system and tracks the defects of the components in order to determine its effect on the system. The WASPAS method was proposed by Zavadskas in 2012. This method is one of the relatively new methods of multi-criteria estimation with very high accuracy, which is actually a combination of two methods, the weighted addition model and the weighted multiplication model (WPS3). The accuracy of the WASPAS method is higher than any of the two mentioned methods. The purpose of FMEA is to determine the causes of defects in systems and provide solutions to reduce or eliminate identified defects in order to increase process reliability.The present research is of the type of present research based on evaluation-analytical method; And it is survey type. In this research, using the FMEA method, the most important potential risks of the power plant were analyzed based on pseudo-accidents and power plant accidents. For each potential risk, risk probability, risk severity, risk discovery probability and finally risk rating were determined according to table (1). The focus of the FMEA method is prevention-based and completely subjective. This method requires predicting errors and providing a solution to prevent errors. After determining the risk rating of each activity, using WASPAS software, hierarchical analysis of criteria and options was done, and finally, the prioritization of options was determined. One of the parameters that can be considered in choosing a multi-criteria decision-making method is the accuracy of these models. Also, these researchers suggest that the combination of two models can increase the accuracy of the results of the models. The accuracy of the results of multi-indicator decision making models (WSM) (weighted summation model) and WPS (weighted production model) is relatively well known. Also, the accuracy of composite models has been analyzed by researchers. The results of researchers' studies have confirmed that the accuracy of the combined model is much higher compared to the accuracy of these models before being combined. One of these combined models is the cumulative weight production evaluation model (Wasps). This model can be highly effective in complex decision-making problems, and the results obtained from this model are highly accurate. The model process is as follows:First step: obtaining and standardizing the decision matrix;The second step: calculating the variance of the values of the initial normalized criteriaThird step: calculation of variancesFourth step: Calculate Qi and to rank the optionsThe purpose of this research was to identify and analyze potential risks in the power plant using the combination of FMEA and Waspas methods. In total, site visit activities, repairs, loading, cutting and using grinding stones; A total of 16 risks were identified, and among the 16 identified risks, noise pollution and vibration in the power plant were assigned the highest degree of risk probability with the number 7 and 5, respectively. The highest risk intensity number is number 9, which includes the activities of visiting the combustion chamber, air cutting, repairs and loading. The most important control measures proposed to reduce the risk of loading activity are periodic inspection of equipment and use of rigger. For the site visit activity, the proposed measures include rotating visits of the personnel to the site and placing a camera and an emergency way in the place of the combustion chamber. Suitable control measures for repair activities are the use of personal protective equipment and periodic inspection of the used equipment. Considering the preference of working with a grinding stone due to the possibility of breaking the grinding plate and other things, safety glasses and helmets should be used when working with it. Bahrami et al. (2017) conducted a research titled environmental risk assessment of Kermanshah Petrochemical Complex using FMEA method. that the result of the research was the expression of more fuzzy noise pollution, which is in line with some of the results of the present research.