Where to conduct the SIL assessment for chemical plants’ safety instrumented systems
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Where is the SIL assessment for chemical plants’ safety instrumented systems carried out, and how is the level determined?
This is a systematic project; a few short sentences cannot solve your problem. Implementing it is somewhat similar to a quality management system: selecting qualified personnel (team leaders who have received professional training, have experience in evaluations, and have worked in related fields for over 5 years) – forming a team – gathering information – analyzing and discussing – drafting documents – approving implementation – verifying effectiveness – conducting regular reviews. What I said isn’t professional enough and lacks detail:$
Generally, it is classified through HAZOP analysis and LOPA analysis, and then verified via SIL assessment. So, based solely on the SIL classification, it involves conducting a HAZOP analysis in the first two steps, and then using the results of that HAZOP analysis to perform a LOPA quantitative analysis in order to determine the SIL level for each circuit.
Please have a design institute or a professional safety company (such as Qingdao Safety Engineering Institute, etc.) handle it.
This post was last edited by Sunk Bamboo_PCQT on 2019-1-24 00:02. I recommend a book titled \"Applications of Safety Instrumented Systems in the Process Industry\" – it’s worth purchasing and reading, as it remains relevant over time. I have already read this. \"Engineering Design and Application of Safety Instrumented Systems (2nd Edition)\” – I haven’t bought this book yet; I think the translator is the author of the previous book, which is good.
This post was last edited by Yunmu on 2019-3-26 at 12:36. If the project is in the design phase, an SIL classification is required. The SIL classification is determined based on the company’s risk matrix, through LOPA analysis of protection layers. If it is an operational device, SIL classification and verification must be carried out. Before carrying out LOPA on a certain interlock SIF circuit, a Hazard and Operability Analysis HAZOP is often conducted as a basis to identify risks. It is generally carried out by professional security consulting firms, which then issue a report.
This post was last edited by Wang Tianze on 2019-3-19 at 17:26. The SIL classification is determined in accordance with the guidelines for establishing the required safety integrity level specified in IEC61511-3 (as well as GB/T21109-3), using the Layer of Protection Analysis (LOPA) method. The LOPA method allows determining the appropriate level of risk reduction that SIF must provide in order to keep the risk within acceptable limits. Independent Protection Layers (IPLs) eliminate the subjectivity of qualitative methods, while LOPA provides specific requirements for evaluating and identifying these independent protection layers.
Safety integrity level verification aims to determine the safety integrity level of an organization’s existing safety instrumented functions by conducting computational analyses of the failure probability requirements for various components within those safety function circuits, in order to confirm whether they meet the minimum SIL level required for the desired safety function integrity level. (Safety integrity level verification employs the Markov model analysis method)
The SIL classification methods include the matrix method, risk map method, and LOPA method
The common approach is to first conduct a HAZOP, then select scenarios for LOPA analysis in order to determine the SIL level for the SIFs. Then design the circuit, purchase instrument components that meet the SIL level, and calculate the PFD to determine whether the requirements are satisfied.
First, conduct a HAZOP analysis and a LOPA protection layer analysis; then determine the SIL level to decide whether a SIS system is needed; finally, carry out SIL verification. If higher requirements exist, a dual prevention mechanism and PSM process safety management are necessary. Professional consultation hotline: 147-0046-8192