Offer SIL Certification and SIL Grading Consultancy Services - Shenzhen Zhongnuo Testing Technology Co., Ltd.
What two aspects does the SIL certification primarily examine?
The product itself, as well as the conformity of the hardware and software functions of the intended certified product, to the requirements of IEC61508 or more specific industry functional safety standards, such as hardware failure rates and failure modes.
Another key focus of our evaluation is the quality management system employed during the development process, the qualifications of the R&D personnel, and the overall organizational structure, ensuring that the methods used and the document system adhered to throughout the product development meet relevant standards.
Through these two aspects of evaluation, we can say that from the entire company to the R&D process and finally to the formation of specific certified products, a complete closed loop has been established, ensuring the reliable and safe realization of the product's safety functions.

What is the failure rate of SIL certification?
During the SIL certification process, a concept we often refer to is the equipment failure rate, which is a core term in SIL certification. It can be said that without the determination of the failure rate, the SIL certification is incomplete and not comprehensive. So, what exactly is the concept of the failure rate?
Firstly, to understand failure rate, we must comprehend what is meant by "failure." According to GB/T 20438.4 and also the definition in IEC 61508, "failure" refers to "the termination of the ability of a functional unit to perform a required function, or the operation of the functional unit in a non-required manner." A more intuitive way to understand this is: normally, y=f(x), but upon failure, it becomes y≠f(x), where f() represents the pre-set function, and y denotes our safety expectations. This also explains why "function" is the same word used for both functions and functions in English.
This statement might be too formal and not easily understood by the general public. So, speaking in layman's terms, it's like comparing it to a lighting system. If the lighting system doesn't illuminate or doesn't do so according to our set requirements, it's considered to be malfunctioning.
So said, you might know that a product is considered defective when it doesn't function according to our specified requirements. Then, what's the probability of this happening? That's the failure rate.
After understanding what failure is, we can start to categorize its types. In the concept of functional safety, failures can be divided into two main categories based on their generation causes: systematic failure and random hardware failure. Among them, random hardware failure is quantifiable. The calculation process of PFDavg is based on a probabilistic analysis of random hardware failure.
In the SIL certification, we aim to determine the product's failure rate by analyzing the theoretical model of the product and utilizing empirical data from its market sales, thereby combining it with other parts of the SIL certification to form a comprehensive system, ensuring the reliable and safe execution of safety functions.

The standard for SIL Safety Integrity Level certification primarily includes:
1. IEC61508—Establishes basic safety requirements for both conventional system operation and fault prediction capabilities. These requirements encompass general safety management systems, specific product design, and process design that meets safety requirements, aiming to avoid both systematic design failures and random hardware failures.
2. IEC61511 – A functional safety standard specifically for safety instrumented systems in the process industry. It is a domain standard issued by the International Electrotechnical Commission (IEC) following the foundational functional safety standard IEC61508. In China, the coordinating standard for IEC61511 is GB/T 21109.
3. ISO 13849-1 - Comprehensive safety assessment from components to systems. This standard also offers designers more quantifiable design implementation methods.
4. IEC 62061 – Standard for electrical systems.
5. IEC61326-3-2 – Specifies additional requirements for immunity levels of safety-related equipment, including low-probability end conditions that may occur at the site.
6. ISO 26262 – Primarily focused on specific electrical devices, electronic equipment, and programmable electronic devices within the automotive industry, designed for automotive applications, aiming to enhance the functional safety of automotive electronics and electrical products.

The content of SIL level assessment includes:
1. System Evaluation
-Risk analysis, classified according to risk diagram (ASIL/SIL/PL)
Review of specifications and safety requirements
Concept and Design Analysis
– Verification and Confirmation
2. Software and Tool Evaluation
– Testing of development tools and other communication protocols
Structural Analysis
3. Hardware Assessment
Probability Analysis
Failure Analysis
4. SIL Certification
Components and Systems SIL Certification
Safety Process SIL Certification
- Granting of systems, semiconductor, development tools, and process testing certifications
5. Additional Services
Risk Tolerance and Risk Analysis
Test and evaluate hardware and software for security during the development process
Conceptual Assessment (Initial Inspection)
Functional Safety Management (FSM)
- Security, reliability, and availability analysis
Qualified Assessment Meeting Relevant Safety Standards
These services are aimed at manufacturers of components, subassemblies, and systems for the automotive industry (including electric), elevators, power plants, machinery, and process sectors. They support the fulfillment of due diligence obligations and ensure the correct application of the standard, contributing to enhanced safety levels and the reduction of residual risks. Standards IEC61508 and others can be integrated into existing quality management systems in a beneficial manner. The implementation of regulations and provisions within the standards provides a reliable basis for decision-making, particularly regarding safety structures, testing procedures, and tools. Development outputs can be verified at an early stage, thereby reducing development time and costs. Additionally, certification enhances the image and boosts the company's competitive position in the market.
SIL certification is a third-party assessment, verification, and certification based on standards such as IEC 61508 (GB/T 20438), IEC 61511 (GB/T 21109), IEC 61513, IEC 13849-1, IEC 62061, and IEC 61800-5-2, which evaluate and confirm the Safety Integrity Level (SIL) or Performance Level (PL) of safety equipment. Functional safety certification primarily involves documentation management (FSM) assessments for the development process of safety equipment, hardware reliability calculations and evaluations, software assessments, environmental testing, and EMC electromagnetic compatibility testing. SIL certification is divided into four levels: SIL1, SIL2, SIL3, and SIL4, encompassing both product and system levels, with SIL4 having the highest requirements.