CAS Automation Specialist Safety & Standards Flashcards
6 cards from real CAS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 CAS Automation Specialist Safety & Standards flashcards as text
What is the definition of Probability of Failure on Demand (PFD) in a safety system?
Answer: The average probability that a safety function fails to respond when a demand occurs
PFD is the average probability that a safety instrumented function will fail to perform its intended function when called upon.
Which safety architecture uses redundancy where all channels must agree before a protective action is taken?
Answer: 2oo2 (2-out-of-2)
2oo2 (2-out-of-2) requires both channels to vote for a shutdown, reducing spurious trips but lowering fault tolerance.
In NFPA 70E, arc flash boundaries are established to protect workers from which specific hazard?
Answer: Thermal energy from an electrical arc
NFPA 70E arc flash boundaries define safe working distances based on incident energy (cal/cm²) from an electrical arc event.
What does the term 'proof test interval' mean in the context of safety instrumented systems?
Answer: The periodic interval at which a safety function is tested to detect dangerous undetected failures
The proof test interval is the time period between full functional tests of a SIS to reveal and correct hidden dangerous failures.
Which standard specifically addresses cybersecurity for industrial automation and control systems (IACS)?
Answer: ISA/IEC 62443
ISA/IEC 62443 provides a comprehensive framework for cybersecurity in industrial automation and control systems.
In a risk matrix used during PHA, which two dimensions are typically evaluated?
Answer: Probability of occurrence and severity of consequence
Risk matrices plot the likelihood (probability) of a hazardous event against the severity (consequence) of its outcome.