SIL Risk Assessment & Hazard Analysis 2

Question 1

In a Hazard and Operability Study (HAZOP), what does the guideword 'MORE' signify?

Accepted Answer

Quantitative increase of a parameter above its intended value

Answer

The HAZOP guideword 'MORE' indicates a quantitative increase in a process parameter such as flow, temperature, or pressure beyond its design value.

Question 2

Which risk reduction technique involves eliminating the hazard entirely rather than controlling it?

Accepted Answer

Inherently safe design

Answer

Inherently safe design (ISD) eliminates hazards at the source rather than adding protective barriers, representing the highest level in the safety hierarchy.

Question 3

What does a Fault Tree Analysis (FTA) 'OR gate' indicate?

Accepted Answer

Any single input event is sufficient to cause the output event

Answer

An OR gate in FTA means that any one of the input events alone is sufficient to cause the output (top or intermediate) event.

Question 4

In IEC 61511, the term 'Process Demand' refers to:

Accepted Answer

The rate at which the process requires the SIF to take action

Answer

Process demand rate is the frequency at which a hazardous condition arises that requires the safety instrumented function to respond.

Question 5

Which layer of the Layers of Protection Analysis (LOPA) is NOT considered an Independent Protection Layer (IPL)?

Accepted Answer

Basic Process Control System (BPCS)

Answer

The BPCS is generally not credited as an IPL when it is also the initiating cause of the hazard scenario being analyzed.

(SIL) Safety Integrity Level Certified Practice Test

(SIL) Safety Integrity Level Certified Practice Test

SIL Risk Assessment & Hazard Analysis 2