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SIL certification is a third-party assessment, verification, and certification process that evaluates and confirms the Safety Integrity Level (SIL) or Performance Level (PL) of safety devices, based on standards such as IEC 61508, IEC 61511, IEC 61513, IEC 13849-1, IEC 62061, and IEC 61800-5-2. Functional safety certification primarily involves assessments such as Document Management (FSM) for the development process of safety devices, calculations and evaluations of hardware reliability, software evaluation, environmental testing, and EMC electromagnetic compatibility testing. The Committee for European Electrical Standardization (abbreviated as CENELEC) is one of the three major standardization organizations in Europe; CENELEC is responsible for European standardization in the field of electrical engineering. CENELEC, together with ETSI for telecommunications standardization and CEN (for standardization in all other technical fields), forms the European standardization system. SIL certification is divided into 4 levels in total: SIL1, SIL2, SIL3, and SIL4, covering both the product and system levels. Among them, the requirements for SIL4 are the highest. SIL certification is primarily based on standard 1.IEC 61508: Functional Safety of Electrical/Electronic/Programmable Electronic Safety-Related Systems. The IEC61508 standard specifies the basic safety requirements in terms of both normal system operation and fault detection capabilities. These requirements cover general safety management systems, specific product design, and process design that meets safety requirements, with the goal of avoiding both systematic design flaws and random hardware failures. The main objectives of the IEC61508 standard are: • To provide a systematic approach for ensuring safety throughout the lifecycle of all components in safety-related systems, including both software and hardware; • To offer methods for determining the safety functional requirements of such systems; • To establish basic standards that can be applied directly in all industrial fields. At the same time, it can also guide standards in other fields to ensure consistency in their drafting (such as basic concepts, technical terms, requirements for specified safety functions, etc.); • Encourage operators and maintenance departments to use computer-based technologies; • Establish a standard architecture and system with unified and coherent concepts. 2. IEC61511: Functional safety requirements for safety instrumented systems in the process industry. IEC61511 is a functional safety standard specifically designed for safety instrumented systems in the process industry. It is a sector-specific standard issued by the International Electrotechnical Commission following the basic functional safety standard IEC61508. The equivalent standard in China for IEC61511 is GB/T 21109. In the process industry, instrument safety systems are used to carry out instrument safety functions, and the IEC61511 standard addresses the issue of what levels of safety integrity and performance instruments should achieve. For verifying the safety functions of safety-related devices, the SIL level is a globally recognized method for defining safety integrity. For the process control industry, the main relevant international standards are IEC 61508 (the basis for designing and operating safety instrumented systems). IEC 61511 focuses on systems used in process control applications; device designers follow IEC 61511 standards while carrying out their designs in accordance with IEC 61508 standards. 3. ISO13849-1: Mechanical safety – Safety-related parts of control systems – Part 1: General principles for design. The new version of the ISO13849-1 standard is set to come into effect at the end of 2011, marking a new milestone in the field of mechanical functional safety. Building on the previous requirement for system determinism, additional assessments of system failure probabilities have been introduced, thereby enabling a comprehensive safety evaluation from components to the entire system. At the same time, this standard also provides designers with more quantifiable methods for design implementation, such as parameters like system safety level (PLr), mean time to failure without danger (MTTFd), system diagnostic coverage (DC), and common cause failure prevention (CCF), thereby effectively addressing the issue that the original EN954-1 standard could not enable quantitative assessment of system safety. The new version of the ISO13849-1 standard offers more effective safety assessment solutions for some new control methods. It can enhance the safety level of mechanical equipment with increasingly complex control systems, ensuring production safety and efficiency. By integrating new technologies and design expertise, it helps businesses improve their overall efficiency, productivity, and flexibility, ensures continuous production, reduces downtime, and lowers costs associated with development, operation, and maintenance. Implementing this standard as soon as possible will enable machinery manufacturers to gain a competitive edge in the fierce market competition. 4. IEC62061: Mechanical safety – Functional safety of electrical, electronic and programmable electronic control systems associated with safety. Both the IEC/EN 62061 and EN ISO 13849-1:2008 standards cover electrical control systems related to safety. By adopting these two standards, the same level of safety performance and safety integrity can be achieved. The methods employed in each standard vary, but they are all suitable for their respective audiences. EN ISO 13849-1:2008 specifies a limiting case in Table 1 of its explanatory section. When complex programmable technologies are used, the highest PL performance level should be defined as PLd. To enable the use of complex security functions that can be implemented by previously non-traditional system architectures, the IEC/EN 62061 standard provides corresponding methods. To provide a more direct and simpler path for implementing more conventional safety functions using a traditional system architecture, the EN ISO 13849-1:2008 standard also offers corresponding methods. The key difference between these two standards is that they are applicable to different technical fields. The IEC/EN 62061 standard is limited to the field of electrical systems. The EN ISO 13849-1:2008 standard applies to hydraulic, mechanical, and electrical systems. The main defined parameters are PFH, MTTF, DC, SFF, etc. 5.IEC61326-3-2: Electrical equipment for measurement, control and laboratory use – Requirements for electromagnetic compatibility (EMC): Safety-related systems and those used to perform safety-related functions (functional safety). The IEC 61326-3-1 and IEC 61326-3-2 standards have been published, specifying additional requirements for the immunity levels of safety-related equipment, including extreme conditions that may occur anywhere with an extremely low probability. The test simulation equipment replicates the severe electromagnetic phenomena that occur under operating conditions, such as transient pulses, which simulate the transient states in digital circuits or digital signal transmission. To increase the confidence in the electromagnetic immunity of the Safety Integrity Level (SIL), more pulses are applied during electromagnetic phenomenon resistance tests compared to the basic standards, or the test duration is extended and the test level is raised. For example, for devices used in SIL3, the level of the electrostatic rapid transient test is 4 kV, and the test duration should be 5 times the time specified in the basic standards. 6. ISO26262: Functional Safety for the Design of Road Vehicle Systems. The purpose of establishing the ISO 26262 standard is to provide a better understanding of safety-related functions and to explain them as clearly as possible. ISO 26262 is derived from IEC 61508, the basic standard for functional safety of electronic, electrical, and programmable devices. It is specifically aimed at certain electrical components, electronic devices, and programmable electronic devices used in the automotive industry, and serves as an international standard to enhance the functional safety of automotive electronics and electrical products. As soon as this standard was introduced, it received significant attention from major automobile manufacturers and auto parts suppliers, who actively promoted its implementation in product development. Based on the IEC 61508 standard, the ISO 26262 standard defines the safety of use for electrical and electronic systems. One of the major challenges in automobile design is how to predict potential hazards and risks in advance, and to employ appropriate methods to reduce these risks. To facilitate this process, ISO requires that a “hazard and risk analysis” be conducted at the beginning of development work. The automotive industry relies on high-performance electronic components for the safety control of vehicles. The ISO 26262 functional safety standard, established and recognized by leading automobile manufacturers around the world, sets requirements for the design of electronic components as well as software and hardware used in vehicles. With the introduction and implementation of ISO 26262, it will be possible in the future to reduce the risks associated with vehicles as well as the severity of damages in the event of accidents, thereby enhancing the international competitiveness and adaptability of China’s vehicle industry. 7. IEC61800-5-2: Standard for electric drives with variable speed. Part 5-2: Functional safety requirements. IEC61800-5-2 defines the safety functions of safety-driven systems, including a range of stopping functions (Stop), namely: • Safe Torque Off (STO) ； • Safety Stop 1/SS1 (Safety Stop 1)/ Safety Stop 2/SS2 (Safety Stop 2) • Safety Operation Halt. IEC61800-5-2 also defines certain monitoring functions, including acceleration safety limits ； Walking distance safety limit ； Safety limits for movement direction ； Speed safety limit ； Moment/Force Safety Limits ； Position safety restrictions ； Motor temperature safety limits. The IEC61800-5-2 standard specifies functional safety requirements for systems such as safety encoders, safety decoders, AC servo systems, servo drives, and servo motors. For example, motor controllers that meet the requirements of functional safety technology will support safety functions such as Safe Torque Off (STO) and Safe Stop 1 (SS1), in order to prevent accidental startup; the product design must comply with the requirements specified in the EN 61800-5-2 standard. The IEC61800-5-2 standard has been translated into a national standard, with the standard number GB/T 12668.5.2. The corresponding standardization committee in China is the Sub-Technical Committee on Semiconductor Power Converters for Speed Control Electrical Drives (TC60/SC1) under the National Technical Committee for Power Electronics Standardization. 8. EN50156 – Measurement and control digital data communication – Part 3: Functional safety requirements for industrial networks. This standard defines the following main aspects: 1. The basic principles for implementing the requirements related to secure data communication as specified in IEC 61508, including provisions regarding potential errors in data transmission, countermeasures, and aspects affecting data integrity. 2. General requirements for various technical implementations. 3. Independent descriptions of the functional safety requirements for different communication protocol families. 4. Definition of several secure communication layers, which serve as part of the communication service protocols in the IEC61784-1 and IEC61158 standard series. 9. EN50126 – Railway applications: Specifications and guidelines for reliability, availability, maintainability, and safety (RAMS). This standard defines the RAMS aspects of systems, namely reliability, availability, maintainability, and safety, and specifies the management and requirements related to RAMS at various stages throughout the system’s safety lifecycle. As an important criterion for measuring the quality of system services, RAMS is achieved through design concepts and technical methods at every stage of the system’s safety lifecycle. 10. EN50128 – Railway applications: Software for railway control and protection systems. This standard establishes safety integrity levels (SIL) for the software used in railway control and protection systems. It sets corresponding standards based on various safety requirements, and defines procedures and specifications for the entire software development, evaluation, and testing process. These include guidelines regarding software requirements, test specifications, software architecture, software design and development, software verification and testing, software and hardware integration, software validation and assessment, quality assurance, lifecycle management, and documentation. 11. EN50129 – Railway applications: Safety-related electronic systems. For safety management, the concept of a safety life cycle introduced by IEC61508 is applied; that is, for the safety-related components of such systems, design is carried out following these steps, and comprehensive safety assessments and verifications are required. The aim is to further reduce human errors related to safety, thereby decreasing the risk of system failures. During the implementation of the SIL assessment, FSchina will, in accordance with the principle of independence between evaluation and auditing, have internationally recognized functional safety software and hardware design engineers at its center carry out the product assessment process ； The assessment results are reviewed by experts from IEC TC 65A, the committee of the International Electrotechnical Commission based at the center, to ultimately produce a report on the product safety integrity level as recognized by CNAS, thereby ensuring the independence and objectivity of this assessment process. It specifically includes the following three stages: The evaluation services for functional safety products mainly comprise three stages: 1. Project initiation stage; 2. Concept approval stage. 2.1. Review of the safety plan; 2.2. Review of the verification and validation plan; 2.3. Evaluation of the fault avoidance measures to be adopted; 2.4. Evaluation of the documentation system to be used; 2.5. Explanations related to functionality and safety; 2.6. Inspection of the fault detection and control measures to be implemented; 2.7. Execution and review of the system FMEA; 2.8. Development of a test plan for the main approval stage; 2.9. Issuance of a concept approval report. 3. Main approval stage: 3.1. Evaluation of the fault avoidance measures already applied throughout the product’s life cycle; 3.2. Evaluation of the product documentation during the development phase; 3.3. Subsystem FMEA; 3.4. Testing of safety-related functions as well as analysis of software and hardware functionalities; 3.5. Testing of software and hardware fault detection techniques; 3.6. Software verification testing checks (main activities in the left branch of the V model, carried out based on requirements provided by the user); 3.7. Inspection of configuration tools (carried out based on requirements provided by the user); 3.8. Inspection of environmental testing, mechanical testing, and EMC testing (these tests can be carried out by the manufacturer or by someone commissioned by the manufacturer); 3.9. Electrical safety testing; 3.10. Calculation of safety-related parameters (SIL, PL, SC, SFF, PFD, PFH, MTTF) or reevaluation of the safety-related reliability parameters provided by the user; 3.11. Inspection and review of user documentation; 3.12. Issuance of an approval report along with a certificate. Through these activities, the Functional Safety Center can issue product testing/experiment reports to enterprises, as well as certificates corresponding to the SIL levels (1/2/3/4) defined by relevant functional safety standards, thereby proving that the enterprise’s products meet the required SIL levels for functional safety. Some typical products that can provide certification consulting services are as follows: - Safety controllers, including ESD, safety PLCs, safety buses, F&G, etc ； (Meets standards: IEC61508, IEC61511, IEC61513, IEC61784-3) – Safety transmitter ； (Meets standards: IEC61508, etc.) – Safety valves, actuators, or integrated actuation units ； (Meets standards: IEC61508, etc.) – Safety grids, safety curtains, safety switches, etc ； (Meets standards: IEC61508, IEC62061, ISO13849) ； - Safety relay ； (Meets standards: IEC61508, IEC62061, ISO13849, etc.) ； - Safety electronic/electrical products for automobiles ； (Meets standards: IEC61508, ISO26262, etc.) ； - Other electronic/electrical/programmable electronic products with safety requirements.