The book describes systematic methods and techniques for selecting safety integrity levels for safety instrumented systems (SIS). Numerous methods that are used in industry are presented, with an emphasis on layer of protection analysis, which is rapidly becoming the most common. The reason for its popularity stems from its ease of use while providing accurate results. This technique emphasizes accounting for existing layers of protection. By doing so, the SIS is not over-designed and over-priced. This technique ensures that the maximum return on risk reduction investments is achieved. This reference demonstrates the application of quantitative risk analysis techniques and tools to the problem of safety integrity level selection. The authors bring the topic down to earth, explaining the material in a non-threatening and approachable way. They distill essential theory into a format that the average control systems engineer can quickly apply. This is not a generic theoretical dissertation, nor a comprehensive treatment of the topic of quantitative risk analysis.
It is a focused process for applying specifically to the problem of selecting safety integrity levels for safety instrumented systems.