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6. Method for assessing the probability of failure of a RIS
6.1 LEGO approach
The simplified analytical formulas are all based on a "LEGO" approach, which involves estimating the PFD avg of the FIS by assembling (i.e. summing) the average PFD avg of each block.
As previously explained and shown in figure 18 , a RIS generally comprises three subsystems.
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Method for assessing the probability of failure of a RIS
Bibliography
Standards and norms
- Analysis techniques for dependability – Reliability diagram block and Boolean methods - IEC 61078 -
- Functional safety of safety-related electrical/electronic/programmable electronic systems – chapters 1 to 7 - IEC 61508 -
- Sécurité fonctionnelle des systèmes instrumentés de sécurité pour le secteur de l'industrie des procédés continus - IEC 61511 -
- Analysis techniques for dependability – Reliability...
Organizations
French National Institute for Industrial Environment and Risks (INERIS) http://www.ineris.fr
Instrumentation Society of America (ISA) https://www.isa.org/http://www.isa-france.org
...
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