Functional Safety Fundamentals
The History of Functional Safety
Functional safety did not arrive in a tidy sequence of accidents, regulations, and standards. The committees, the regulators, the hardware, and the disasters were all moving at once. A narrative…
Functional Safety Fundamentals, SIL Math and Reliability
2oo3 Architecture: The Design Decision Behind Majority Voting
2oo3 voting gives a SIF a hardware fault tolerance of 1 without doubling the spurious trip rate. See how 2oo3 compares with 1oo1, 1oo2, and 2oo2 on the same numbers,…
Functional Safety Fundamentals
Who Certifies Functional Safety Equipment, and Who Accepts It
A practitioner’s map of who certifies functional safety equipment and who accepts it: the manufacturer’s own documents, the certification body and the accreditation body behind it, Global ACI at the…
Functional Safety Fundamentals
Functional Safety Assessment (FSA) vs. Audit: What’s the Difference?
A functional safety assessment and an audit get used interchangeably, but they answer different questions and sit at different points in the IEC 61511 life-cycle. One judges whether the required…
Functional Safety Fundamentals
Functional Safety Is Not the Same as Occupational Safety
Occupational safety, process safety, and functional safety are not the same discipline, and treating them as interchangeable is a common mistake at process facilities. Different training, different credentials, different daily…
Functional Safety Fundamentals, SIL Math and Reliability
SIL Verification: The Three Gates Every SIF Must Clear
SIL verification under IEC 61511 is three independent gates, all of which must pass: PFDavg, systematic capability, and architectural constraints. The gate that gets the most attention rarely fails an…
Functional Safety Fundamentals
Functional Safety for the Process Industry: 10 Core Concepts Every Engineer Should Know
Functional safety in the process industry is more than calculations—it's a life-cycle approach to reducing risk. This guide explains IEC 61511, SIS, SIL, LOPA, and how safety systems actually work…
