P1: Reliability data for components used in safety systems
What are the main reliability data for components used in Security Systems?
P2: The Safe Failure Fraction and the Architectural Constraints
We remind that there are four types of Failures: Safe failures, dangerous failures, no effect failures and no part failures
P3: Considerations on the Safe Failure Fraction in High and Low Demand
In this article we discuss some critical aspects linked to the use of the SFF. We also provide some requirements for failures to be defined as Detectable.
P4: Functional Safety - PFD calculation
A continuous probability distribution is indicated with f(x) and is usually called Probability Density Function (PDF).
P5: Functional Safety - PFD Calculation Second part
In this article we show how to calculate, in practice, the PFDavg.
P6: The average probability of dangerous failure per hour (PFH)
We will now explore the domain of Safety-related Control Systems working in High Demand. The parameter used in defined as Probability of Failure per Hour and the acronym is PFH.
P7: Functional Safety in High demand - ISO 13849-1 categories
ISO 13849-1 is intended to be used in the design and evaluation of safety-related parts of the control system (SRP/CS) and only the part of the control system that is safety-related falls under the scope of the standard.
P8: Functional Safety in High Demand: Category B, 1 and 2 of ISO 13849-1
ISO 13849-1 is one of the two standards used in machinery and, at least in Europe, it is the most used of the two, the other being IEC 62061.
P9: a comparison between RBD and Markov models for the analysis of Safety Instrumented Systems
Within this article, the main international standards involved in Functional Safety and how they apply the Reliability Engineering Theory are investigated.
PT 10: Functional safety in high demand:The Markov model of Category 2 according to ISO 13849-1
This article is part of a series of articles written on Functional Safety of Machinery.
PT 11: Functional safety in high demand: Categories 3 and 4 according to ISO 13849-1
We now continue with the introduction to Category 3. We present the key features and discuss in detail how the Diagnostic channel can be handled.
PT 12: Functional Safety in High Demand: Introduction to IEC 62061
We recently introduced one of the two standards used to design Safety Control Systems in High Demand: ISO 13849-1. We will now present indicated in the IEC 62061.
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