Control Valve SIL 3 Certification Compliance Standard

Offer SIL Certification, SIL Grading, and other consulting services - Shenzhen ZhongNuo Inspection Technology Co., Ltd.
The standard for SIL Safety Integrity Level certification primarily includes:
1. IEC61508—Establishes fundamental safety requirements for both conventional system operation and fault prediction capabilities. These requirements encompass general safety management systems, specific product design, and process design to meet safety requirements, aiming to prevent both systematic design failures and random hardware failures.
2. IEC61511 - A functional safety standard specifically for safety instrumented systems in the process industry, which is a domain standard introduced 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 the entire system. Additionally, this standard provides designers with more quantifiable methods for design implementation.
4. IEC62061 – Standard in the field of electrical systems.
5. IEC61326-3-2 – Specifies additional requirements for immunity levels of safety-related equipment, including low-probability end-of-site conditions.
6. ISO 26262 - Primarily focused on specific electrical devices, electronic equipment, and programmable electronic devices within the automotive industry, specifically designed for automotive applications, with the aim of enhancing the functional safety of automotive electronic and electrical products.

The SIL assessment content includes:
1. System Evaluation
-Risk analysis, refer to risk classification chart (ASIL/SIL/PL)
Review of standards and safety requirements
Concept and Design Analysis
– Verification and Confirmation
2. Software and Tool Assessment
- 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 system, semiconductor, development tools, and process testing symbols
5. Additional Services
- Risk Applicability and Risk Analysis
- Test and evaluate hardware and software for security during the development process
Conceptual Evaluation (Initial Inspection)
Functional Safety Management (FSM)
Safety, Reliability, and Availability Analysis
Qualified Assessment Compliant with Relevant Safety Standards
These services are aimed at manufacturers of parts, subassemblies, and systems for the automotive industry (including electric vehicles), 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 improved safety levels and helping to reduce residual risks to a minimum. Standards such as IEC61508 and more can be integrated into existing quality management systems in a beneficial manner. The implementation of regulations and provisions contained in the standards provides a reliable basis for decision-making, particularly regarding safety structures, testing procedures, and tools. Development outputs can be validated at an early stage, while also reducing development time and costs. Additionally, certification enhances the image and elevates the company's reputation in the competitive market.

The SIL Functional Safety Certification applies to all equipment used for implementing process control safety functions, mainly categorized into electrical components and safety systems.
1. Electrical Components: Actuators, solenoid valves, field sensors, pressure transmitters, temperature transmitters, level transmitters, level switches, programmable controllers, logic solvers, field safety actuators (pneumatic/liquid/eletrical), safety switches, safety valves, gate valves, solenoid valves, safety interlocks, etc.
2. Safety Systems: SIS (Safety Instrumented System), ESD (Emergency Stop System), Instrument Protection System (IPS), Burner Management System (BMS), F&G (Fire and Gas Protection System), HIPPS (High-Pressure Pipeline Protection System), PSD (Process Shutdown System).
3. Other: Electronic/Electrical/Programmable electronic products with safety requirements.

What is the failure rate of SIL certification?
During the SIL certification process, a concept we often mention is the failure rate of equipment, which is a core term in SIL certification. One could say that without determining the failure rate, the SIL certification is incomplete and not comprehensive. So, what exactly is the concept of failure rate?
Firstly, to understand failure rate, we need to grasp what "failure" means. According to GB/T 20438.4 and also the definition in IEC 61508, failure is "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 it is: normally, y=f(x), but after failure, it becomes y≠f(x), where f() represents the pre-set function, and y stands for our safety expectations. This also explains why "function" is the same word for both function and function in English.
This statement might be too formal and not easily understood by the general public. So, speaking in layman's terms, let's compare it to a lighting system. If the lighting system doesn't light up or doesn't light up as per 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 likelihood of this happening? That's the failure rate.
Understood what failure is, we can then categorize the types of failure. In the concept of functional safety, failures can be divided into two main categories based on their cause of generation: 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 failure rate through the analysis of product theoretical models and market sales experience data, thereby integrating it with other parts of the SIL certification to form a comprehensive system, ensuring reliable and secure execution of safety functions.
SIL certification is a third-party assessment, verification, and certification process 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 assessments of document management (FSM) 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 being the most stringent.