Process Safety and Consequence Analysis Flashcards

What factors determine the consequence of failure for pressurized equipment containing flammable fluids?

Answer: Fluid type, inventory, release rate, detection/isolation systems, and surrounding targets

Consequence analysis for flammable fluids considers the type of fluid (flash point, boiling point), available inventory, hole size and release rate, effectiveness of detection and isolation systems, and proximity of personnel and critical equipment.

What is the difference between a Level 1 and Level 3 RBI assessment?

Answer: Level 1 is qualitative/screening; Level 3 is fully quantitative with detailed analysis

Level 1 RBI uses qualitative or semi-quantitative screening methods for initial prioritization, while Level 3 uses fully quantitative probabilistic analysis with detailed consequence modeling and probability calculations.

How are environmental consequences evaluated in an RBI assessment?

Answer: By assessing potential soil, water, and air contamination from released fluids

Environmental consequence evaluation considers the toxicity and volume of potentially released fluids, their mobility in soil and groundwater, proximity to water bodies and sensitive ecosystems, and regulatory cleanup requirements.

What is a safeguard in the context of RBI consequence analysis?

Answer: Any system or procedure that reduces the probability or consequence of a failure event

Safeguards include detection systems, isolation valves, relief devices, containment structures, emergency response procedures, and other measures that either prevent failures or mitigate their consequences.

What is the significance of Maximum Allowable Working Pressure (MAWP) in RBI?

Answer: It defines the maximum pressure a vessel can safely operate at, based on its current condition

MAWP is the maximum pressure a pressure vessel is designed to withstand at a designated temperature based on current wall thickness, serving as a key parameter in both fitness-for-service and remaining life calculations.

How does equipment complexity affect RBI assessment?

Answer: Complex equipment with multiple damage mechanisms requires more detailed analysis and targeted inspection plans

Equipment with multiple process streams, varying conditions, and several potential damage mechanisms requires more comprehensive RBI analysis with targeted inspection plans addressing each damage mechanism at its most susceptible locations.