CCST Safety Standards & Regulatory Compliance in Control Systems 2 — Questions and Answers
Question 1: Which IEC standard specifically addresses functional safety of electrical/electronic/programmable electronic safety-related systems?
- IEC 61511
- IEC 61508 (Correct answer)
- IEC 62443
- IEC 60079
Correct answer: IEC 61508
IEC 61508 is the foundational standard for functional safety of E/E/PE safety-related systems, covering the entire safety lifecycle.
Question 2: What does SIL stand for in the context of functional safety standards?
- Safety Integrity Level (Correct answer)
- System Instrumentation Limit
- Safety Interlock Logic
- Sequential Interrupt Latch
Correct answer: Safety Integrity Level
SIL (Safety Integrity Level) is a measure of the risk reduction provided by a safety function, ranging from SIL 1 (lowest) to SIL 4 (highest).
Question 3: Under OSHA's Process Safety Management (PSM) standard 29 CFR 1910.119, which chemical threshold triggers PSM requirements for flammable liquids?
- 1,000 pounds
- 5,000 pounds
- 10,000 pounds (Correct answer)
- 25,000 pounds
Correct answer: 10,000 pounds
PSM requires 10,000 pounds as the threshold quantity for flammable liquids at or above their normal boiling point.
Question 4: Which layer of protection concept is used in LOPA (Layer of Protection Analysis) to quantify risk reduction?
- Risk Reduction Factor (RRF) (Correct answer)
- Process Hazard Analysis (PHA)
- Safety Instrumented Function (SIF)
- Probability of Failure on Demand (PFD)
Correct answer: Risk Reduction Factor (RRF)
RRF (Risk Reduction Factor) quantifies how much each independent protection layer reduces risk frequency in a LOPA study.
Question 5: In ISA-84 / IEC 61511, what is the term for the complete set of hardware and software that implements one or more safety instrumented functions?
- Safety Control System (SCS)
- Safety Instrumented System (SIS) (Correct answer)
- Emergency Shutdown Device (ESD)
- Process Control Network (PCN)
Correct answer: Safety Instrumented System (SIS)
A Safety Instrumented System (SIS) is the complete system—including sensors, logic solvers, and final elements—that performs one or more SIFs.
Question 6: What is the primary purpose of a Pre-Startup Safety Review (PSSR) under OSHA PSM regulations?
- Confirm that new equipment meets design specifications before introducing hazardous materials (Correct answer)
- Conduct annual revalidation of existing process hazard analyses
- Train operators on new safety procedures
- Verify insurance coverage for new installations
Correct answer: Confirm that new equipment meets design specifications before introducing hazardous materials
A PSSR ensures that construction and equipment are in accordance with design specs and safety, health, and environmental requirements before startup.
Question 7: Which NFPA standard governs the installation of fire and gas detection systems in industrial occupancies?
- NFPA 70
- NFPA 72 (Correct answer)
- NFPA 13
- NFPA 101
Correct answer: NFPA 72
NFPA 72 (National Fire Alarm and Signaling Code) covers the installation, testing, and maintenance of fire alarm and gas detection systems.
CCST Safety Standards & Regulatory Compliance in Control Systems 2
Which IEC standard specifically addresses functional safety of electrical/electronic/programmable electronic safety-related systems?