The Experts below are selected from a list of 30 Experts worldwide ranked by ideXlab platform
Yoshinobu Sato - One of the best experts on this subject based on the ideXlab platform.
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Safety Achieved by the Safe Failure Fraction (SFF) in IEC 61508
IEEE Transactions on Reliability, 2008Co-Authors: I. Yoshimura, Yoshinobu SatoAbstract:The present paper examines the effect of Safe Failure Fraction (SFF) constraints on hazardous-event rates, and discusses the validity of the SFF constraints in IEC 61508. First, the Safe states are categorized into three types of states, and overall systems involving Safety-related systems are classified into six types of systems based on the Safe-state categorization, and the completeness of trips. Next, state-transition models for the systems where the effect of SFF is the greatest are presented, and the hazardous-event rates are analysed for the systems. Then, it is found that, when the effect of the SFF constraints is positive, it is negligible; and when it is negative, it is not negligible for Safety. Thus, we recommend that the application of the SFF constraints to the standard should be put on hold.
I. Yoshimura - One of the best experts on this subject based on the ideXlab platform.
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Safety Achieved by the Safe Failure Fraction (SFF) in IEC 61508
IEEE Transactions on Reliability, 2008Co-Authors: I. Yoshimura, Yoshinobu SatoAbstract:The present paper examines the effect of Safe Failure Fraction (SFF) constraints on hazardous-event rates, and discusses the validity of the SFF constraints in IEC 61508. First, the Safe states are categorized into three types of states, and overall systems involving Safety-related systems are classified into six types of systems based on the Safe-state categorization, and the completeness of trips. Next, state-transition models for the systems where the effect of SFF is the greatest are presented, and the hazardous-event rates are analysed for the systems. Then, it is found that, when the effect of the SFF constraints is positive, it is negligible; and when it is negative, it is not negligible for Safety. Thus, we recommend that the application of the SFF constraints to the standard should be put on hold.
Valentina Luongo - One of the best experts on this subject based on the ideXlab platform.
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Safety analysis in oil gas industry in compliance with standards iec61508 and iec61511 methods and applications
Instrumentation and Measurement Technology Conference, 2013Co-Authors: Marcantonio Catelani, Lorenzo Ciani, Valentina LuongoAbstract:The aim of Functional Safety (FS) is freedom from unacceptable risk of physical injury or damage to health of people directly or indirectly (through damage to property or to environment). The Functional Safety is the part of overall Safety of a system, called Safety Instrumented System that depends on the system operating correctly in response to its inputs, including the Safe management of likely operator errors, hardware Failures and environmental changes. The basic principles of Functional Safety were developed in the military field, nuclear and aerospace industry, and then taken up by rail transportation, process and Oil&Gas industries that have required a development of sector specific standards. According to the Standard IEC61508, the paper presents a case study concerning the evaluation of both the Safe Failure Fraction (SFF) and the Probability of Failure on demand (PFD) for a complex Safety Instrumented System in Oil & Gas application. After a preliminary presentation of the criteria for the SIL (Safety Integrity Level) verification, the work focuses the attention on the method to achieve the PFD. In particular, an approach based on Failure Modes, Effects and Diagnostic Analysis (FMEDA) and Reliability Block Diagram (RBD) is proposed and then a comparison with the approach described in the Standard. The paper aims to clarify how to demonstrate compliance to IEC61508 in OIL& GAS application, with a particular attention to steam turbine, and proposes a simplified technique for reliability analysis of complex Safety Instrumented System, taking into account that the methods should still be possible to comprehend by design engineers.
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the fmeda approach to improve the Safety assessment according to the iec61508
Microelectronics Reliability, 2010Co-Authors: Marcantonio Catelani, Lorenzo Ciani, Valentina LuongoAbstract:According to the Standard IEC61508, the paper presents a case study concerning the evaluation of both the Safe Failure Fraction (SFF) and the probability of Failure on demand (PFD) for a complex system. After a preliminary presentation of the criteria for the Safety integrity level (SIL) verification, the work focuses the attention on the method to achieve the PFD. In particular, an approach based on Failure modes, effects and diagnostic analysis (FMEDA) is proposed and then a comparison with the approach described in the Standard. The paper aims to clarify both the knowledge and the application of the IEC61508 and proposes a technique to satisfy the hardware Safety integrity requirements.
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evaluation of the Safe Failure Fraction for an electromechanical complex system remarks about the standard iec61508
Instrumentation and Measurement Technology Conference, 2010Co-Authors: Marcantonio Catelani, Lorenzo Ciani, Valentina Luongo, R SinguaroliAbstract:The paper discusses a case study concerning the evaluation of the Safe Failure Fraction (SFF) for a complex system. Being such evaluation made according to IEC61508 standard, the paper focused on some related ambiguities. The paper is structured in two phases. First, a reliability prediction of each component of the system is implemented and then a Failure Mode and Effect, Diagnostic Analysis (FMEDA) is applied, we selected FMEDA for more information about Failure condition of each component (modules or systems) under examination. Using this method it is possible to study SFF of different complex systems in compliance with qualitative requirements described in the standard. The main purposes of this paper are to facilitate the application of the standard and to clarify some of related ambiguities and to propose ways to satisfy the requirements related to how hardware architecture may be configured also referred to the architectural constraints.
Marcantonio Catelani - One of the best experts on this subject based on the ideXlab platform.
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Safety analysis in oil gas industry in compliance with standards iec61508 and iec61511 methods and applications
Instrumentation and Measurement Technology Conference, 2013Co-Authors: Marcantonio Catelani, Lorenzo Ciani, Valentina LuongoAbstract:The aim of Functional Safety (FS) is freedom from unacceptable risk of physical injury or damage to health of people directly or indirectly (through damage to property or to environment). The Functional Safety is the part of overall Safety of a system, called Safety Instrumented System that depends on the system operating correctly in response to its inputs, including the Safe management of likely operator errors, hardware Failures and environmental changes. The basic principles of Functional Safety were developed in the military field, nuclear and aerospace industry, and then taken up by rail transportation, process and Oil&Gas industries that have required a development of sector specific standards. According to the Standard IEC61508, the paper presents a case study concerning the evaluation of both the Safe Failure Fraction (SFF) and the Probability of Failure on demand (PFD) for a complex Safety Instrumented System in Oil & Gas application. After a preliminary presentation of the criteria for the SIL (Safety Integrity Level) verification, the work focuses the attention on the method to achieve the PFD. In particular, an approach based on Failure Modes, Effects and Diagnostic Analysis (FMEDA) and Reliability Block Diagram (RBD) is proposed and then a comparison with the approach described in the Standard. The paper aims to clarify how to demonstrate compliance to IEC61508 in OIL& GAS application, with a particular attention to steam turbine, and proposes a simplified technique for reliability analysis of complex Safety Instrumented System, taking into account that the methods should still be possible to comprehend by design engineers.
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the fmeda approach to improve the Safety assessment according to the iec61508
Microelectronics Reliability, 2010Co-Authors: Marcantonio Catelani, Lorenzo Ciani, Valentina LuongoAbstract:According to the Standard IEC61508, the paper presents a case study concerning the evaluation of both the Safe Failure Fraction (SFF) and the probability of Failure on demand (PFD) for a complex system. After a preliminary presentation of the criteria for the Safety integrity level (SIL) verification, the work focuses the attention on the method to achieve the PFD. In particular, an approach based on Failure modes, effects and diagnostic analysis (FMEDA) is proposed and then a comparison with the approach described in the Standard. The paper aims to clarify both the knowledge and the application of the IEC61508 and proposes a technique to satisfy the hardware Safety integrity requirements.
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evaluation of the Safe Failure Fraction for an electromechanical complex system remarks about the standard iec61508
Instrumentation and Measurement Technology Conference, 2010Co-Authors: Marcantonio Catelani, Lorenzo Ciani, Valentina Luongo, R SinguaroliAbstract:The paper discusses a case study concerning the evaluation of the Safe Failure Fraction (SFF) for a complex system. Being such evaluation made according to IEC61508 standard, the paper focused on some related ambiguities. The paper is structured in two phases. First, a reliability prediction of each component of the system is implemented and then a Failure Mode and Effect, Diagnostic Analysis (FMEDA) is applied, we selected FMEDA for more information about Failure condition of each component (modules or systems) under examination. Using this method it is possible to study SFF of different complex systems in compliance with qualitative requirements described in the standard. The main purposes of this paper are to facilitate the application of the standard and to clarify some of related ambiguities and to propose ways to satisfy the requirements related to how hardware architecture may be configured also referred to the architectural constraints.
Lorenzo Ciani - One of the best experts on this subject based on the ideXlab platform.
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Safety analysis in oil gas industry in compliance with standards iec61508 and iec61511 methods and applications
Instrumentation and Measurement Technology Conference, 2013Co-Authors: Marcantonio Catelani, Lorenzo Ciani, Valentina LuongoAbstract:The aim of Functional Safety (FS) is freedom from unacceptable risk of physical injury or damage to health of people directly or indirectly (through damage to property or to environment). The Functional Safety is the part of overall Safety of a system, called Safety Instrumented System that depends on the system operating correctly in response to its inputs, including the Safe management of likely operator errors, hardware Failures and environmental changes. The basic principles of Functional Safety were developed in the military field, nuclear and aerospace industry, and then taken up by rail transportation, process and Oil&Gas industries that have required a development of sector specific standards. According to the Standard IEC61508, the paper presents a case study concerning the evaluation of both the Safe Failure Fraction (SFF) and the Probability of Failure on demand (PFD) for a complex Safety Instrumented System in Oil & Gas application. After a preliminary presentation of the criteria for the SIL (Safety Integrity Level) verification, the work focuses the attention on the method to achieve the PFD. In particular, an approach based on Failure Modes, Effects and Diagnostic Analysis (FMEDA) and Reliability Block Diagram (RBD) is proposed and then a comparison with the approach described in the Standard. The paper aims to clarify how to demonstrate compliance to IEC61508 in OIL& GAS application, with a particular attention to steam turbine, and proposes a simplified technique for reliability analysis of complex Safety Instrumented System, taking into account that the methods should still be possible to comprehend by design engineers.
-
the fmeda approach to improve the Safety assessment according to the iec61508
Microelectronics Reliability, 2010Co-Authors: Marcantonio Catelani, Lorenzo Ciani, Valentina LuongoAbstract:According to the Standard IEC61508, the paper presents a case study concerning the evaluation of both the Safe Failure Fraction (SFF) and the probability of Failure on demand (PFD) for a complex system. After a preliminary presentation of the criteria for the Safety integrity level (SIL) verification, the work focuses the attention on the method to achieve the PFD. In particular, an approach based on Failure modes, effects and diagnostic analysis (FMEDA) is proposed and then a comparison with the approach described in the Standard. The paper aims to clarify both the knowledge and the application of the IEC61508 and proposes a technique to satisfy the hardware Safety integrity requirements.
-
evaluation of the Safe Failure Fraction for an electromechanical complex system remarks about the standard iec61508
Instrumentation and Measurement Technology Conference, 2010Co-Authors: Marcantonio Catelani, Lorenzo Ciani, Valentina Luongo, R SinguaroliAbstract:The paper discusses a case study concerning the evaluation of the Safe Failure Fraction (SFF) for a complex system. Being such evaluation made according to IEC61508 standard, the paper focused on some related ambiguities. The paper is structured in two phases. First, a reliability prediction of each component of the system is implemented and then a Failure Mode and Effect, Diagnostic Analysis (FMEDA) is applied, we selected FMEDA for more information about Failure condition of each component (modules or systems) under examination. Using this method it is possible to study SFF of different complex systems in compliance with qualitative requirements described in the standard. The main purposes of this paper are to facilitate the application of the standard and to clarify some of related ambiguities and to propose ways to satisfy the requirements related to how hardware architecture may be configured also referred to the architectural constraints.
