نشریه علوم و فنون ایمنی ایران
سال دوم شماره 3 (پاییز 1394)

Due to the development of oil and gas resources, this industry is one of hazardous industries. Therefore, prevention is based approach, by identifying and assessing risks have been well received in many ways. The aim of this study was to Risk Assessment of Hazard using of Preliminary Hazard Analysis Technique in The Shiraz refinery. In the cross-sectional study was used Preliminary Hazard Analysis Technique for identification of risks. Then, risk status of hazards was assessed. Finally, control and correction measures were adopted and implemented. The results of this study showed 21 risk zones was identified in operating units in the refinery, that among these risks, 52.38% was in unbearable risk area(11 risks), 14.29% was in medium risk area(3 risks),19.04% was in unbearable risk area(4 risks), 14.29% was in safe risk area(3 risks). The results of this study showed that the major component identified risks; including unbearable and medium, was due to a defect in the design of systems and lack of adequate instructions and training for employees necessary. PHA method or combination of methods to assess the risks of disturbance is not concurrent, and the possibility of errors due to lack of choice in the evaluation of the operational phase, there is.

Patient safety is one of the most important components of the health care quality. One of the factors affecting patient safety is the patient safety climate. Present study aimed to assess patient safety culture among nurses in a hospital in Qom province base on demographic characteristics. This is a cross sectional and descriptive-analytical study which was carried out on 106 nurses in 2014. Researcher developed demographic questionnaire along with patient safety culture were used as tools for gathering data. The data were analyzed by SPSS V20 using t-test, ANOVA and Pearson correlation. Participant had 35.15 and 10.33 as mean and SD of years of old, respectively. Findings revealed that the average of safety climate of patient in the studied statistical population is about 70.15±7.23. In addition, there is no significant difference between education levels and also between groups of work shifts (p<0.05). On the other hand, other demographic factors were not deferent (P>0.05). Despite the fact that studied hospital had acceptable level of patient safety culture, it is critical to pay attention to continuous improvement in the scope of staffs and patients safety to achieve main goals of organization. It should be considered that culture improvement and reaching to transcendental levels is a time-consuming process.

Importance of drilling as upper stream and strategic industry in oil industry and economics of Iran and also necessary of applying ergonomics and occupational health sciences to design equipment and manner of doing activities at drilling rigs in order to work conditions improvements and make safer places were basis of conducting present study at a drilling rig of north oil company of Iran, 2013. This cross-sectional study has been done on 26 different jobs including 136 tasks. Nordic musculoskeletal disorder questionnaire and Quick Exposure Check used to assess ergonomics issues among workers. Moreover, illumination and noise have been evaluated as environmental factors. %95.36 of participants has been in pain in at least one out of nine parts of musculoskeletal system. Back pain was the most common problem among workers; this was in line with QEC results which depicted back's posture was the worst one. Furthermore Illustration was acceptable. In addition, %72 of stations had a noise level more than 80 db. The research results show that High force needed and standing works, manual handling, and unergonomic postures are main risk factors. Base on the results, conducting technical and engineering correction actions to improve ergonomic condition of equipment at drilling rig and make better state of present situation is essential to improve safety level at the workplace as long as process safety.

Natural gas is currently the most important source of energy and income for our country. Increasing the length of gas pipeline and gas pressure drop, required to create gas stations with special and critical facilities and its main is reliability. The aim of this study was to evaluate the reliability of the turbines cooling system as one of the sensitive part of these facilities. This cross-sectional study was done in 2012 on oil cooling system in a pressure boosting station. Data was gathered from the documents, Observation and interview. Fault tree analysis used to identify stop function causes of cooling system and qualitative and quantitative safety analysis and reliability calculation. The final event of electromotor failure with probability of 0.07, oil tank leaks and detection failure with probability of 0.03 and failure in each connection with probability of 0.01 are likely to occur. Likely event that lead to system failure is the failure of the oil tank. Oil tank Leakage, oil tank crack, and failure in connections with the sequence probabilities of 0.03, 0.01, 0.002 are the most likely reasons to stop function of cooling system. System Reliability was equal to 0.9953. Due to the sensitivity of the studied system and the obtained results, it is necessary to improve the system reliability. Therefore special attention to the oil tank maintenance, regular review of connections, pumps and sensors maintenance, are important measures.

The Layer of Protection Analysis (LOPA) is a semi-quantitative risk assessment method which builds upon process hazard analysis techniques like HAZOP. It applies Safety Integrity Level (SIL) approach towards process hazards which determine the total amount of risk reduction level required according to corporate risk acceptable level. LOPA also estimates the required Safety Integrity Level (SIL) for the Safety Instrumented Function (SIF) without more time-consuming techniques such as Fault Tree Analysis (FTA). Besides its ability to be self-documented, it is a powerful analytical tool for assessing the adequacy of process protection layers. Therefore, risk reduction efforts focus towards impact events with the highest risks and provide a rational basis to allocate risk reduction resources efficiently. This paper briefly describes the LOPA methodology, and applies it into a drum in a Methanol production process as a case study. At the end the required Independent Protection Layers (IPL) of the drum is suggested.

Failure Mode and Effects Analysis (FMEA) is a method to systematically identify the failures of systems, subsystems and their components in the different operational processes. The study aimed to identify the failures modes and assess their potential effects on other systems, subsystems and other system components in the electronic unit of combined cycle power plants by FMEA. Based on our design in the first step, a team of experts was formed to identify the potential failures as well as determining their Occurrences (O), severities (S), and capabilities of failure detection (Detectability) (D) leading to their interaction as Risk Priority Number (RPN) in electronics unit. Then, administrative or engineering control measures or Personal Protective Equipment (PPE) were proposed to diminish the high risk failures to lower ones. Obtained data were analyzed with Excel software based on related procedures and guidelines finally. Results showed numbers of potential risks identified in this unit were 37 cases of which 68% were unacceptable level and 32% of those were at acceptable levels. Among these risks, the highest risk of electrocution when replacing coal generators and electrocution caused accidentally energized wires went to an abandoned area of unit with RPN equals to 300. Considering electrocution to the high risk score units, Engineering and management control measures to reduce the risk of accidents caused by Electrocution should has been considered in order to achieve optimum results and reducing the risk to acceptable levels.