Methods of Determining Safety Integrity Level (SIL) Requirements - Pros and Cons

  • W. G. Gulland


The concept of safety integrity levels (SILs) was introduced during the development of BS EN 61508 (BSI 2002) as a measure of the quality or dependability of a system which has a safety function - a measure of the confidence with which the system can be expected to perform that function. It is also used in BS IEC 61511(BSI 2003), the process sector specific application of BS EN 61508.


Demand Rate Total Risk Residual Risk Relief Valve Risk Reduction Factor 


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© Springer-Verlag London 2004

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  • W. G. Gulland

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