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Verify your Safety Instrumented System's readiness with a Stage 3 FSA, ensuring safe operation and compliance with design specifications.

What is hiding under the radar of a plant SIS? Risk assessments define hazard consequences with assumed initiating event frequencies.

A Functional Safety Assessment (FSA) is defined by the IEC 61511 standard as an “investigation, based on evidence, to judge the...

The 2nd edition of IEC 61511 now requires – by use of the word “shall” – that a Stage 4 Functional Safety Assessment (FSA) be conducted...

Is our industry addressing the problems facing it today? We idealize infinitesimally small event rates for highly catastrophic hazards, yet are we any safer? Have we solved the world’s problems? Layers of protection analysis (LOPA) drives hazardous event rates to 10-4 per year or less, yet industry is still experiencing several disastrous events per year. If one estimates 3,000 operating units worldwide and industry experiences approximately 3 major incidents per year, the tr

by Richard E. Hanner & aeSolutions Technical Team There are many critical activities and decisions that take place prior to and during the Safety Integrity Level (SIL) Verification and other Conceptual Design phases of projects conforming to ISA84 & ISA/IEC 61511. These activities and decisions introduce either opportunities to optimize, or obstacles that impede project flow, depending when and how these decisions are managed. Implementing Safety Instrumented System (SIS) pr

Functional Safety & Bayesian Networks Functional safety engineers fol low the ISA/IEC 61511 standard & perform calculations based on random hardware failures. These result in low failure probabilities, which are then combined with similarly low failure probabilities for other safety layers, to show that the overall probability of an accident is extremely low (e.g., 1E-5/yr). Unfortunately, such numbers are based on frequentist assumptions and cannot be proven. Looking at act