Hazard Identification and Quantitative Risk Management

 

The goal of this lecture series is understanding of the modern concepts of Risk and Hazard in Safety Technology. Many international standards, government regulatory groups, corporate management and clients insist on documented safety analysis throughout the life of the process plant. The goal of this lecture series is understanding of the relationships of process safety technology, particularly focused on Qualitative and Quantitative Risk Assessment

 

This lecture series presents the attendee with techniques and underlying basis needed to conduct hazard analysis and risk management projects

 

1st Day – Risk Based Decision Making in Engineering Practice & Design

Overview of the QRA methodology. Specific topics include qualitative vs. quantitative techniques for risk-based decisions, the role of “competent person”, structure of safety standards (with emphasis on documentation and conformity assessment issues), common risk analysis factors in various safety standards, risk communication, hazard screening techniques, individual risk vs. societal risk, risk contours F-N curves  risk acceptance criteria  Short class workshops will be used to illustrate how to use the fundamental ideas background and skills necessary to understand risk and reliability terminology.

 

Featured tools for QRA studies are Fault trees and event trees to model the system-level failures of interest.

 

2nd Day QRA as a part of Safety Management Systems

Interface of QRA in the Process Safety Management system. Particular emphasis on the techniques of HAZOP (HAZard and OPerability studies with qualitative risk ranking) and LOPA (Layer of Protection Analysis) are featured.

LOPA is used to evaluate scenario risk and compare it with risk tolerance criteria to decide if existing safeguards are adequate, and if additional safeguards are needed. Without risk tolerance criteria, there is a tendency to keep adding safeguards in the belief more safeguards are better. Eventually safeguards will be added that are unnecessary and may add complexity that can result in new unidentified hazard scenarios. LOPA helps focus limited resources on the most critical safeguards. Barrier Analysis and Bow Tie analysis are similar techniques that will be briefly examined.

3rd Day QRA

This lecture focuses on calculating basic system reliability characteristics. Specifically, the use component failure and human error data to estimate overall reliability and availability characteristics for systems. Concepts include system reliability, availability, expected number of failures, mean time to failure, mean time to repair, redundancy and dependability. Several workshops will be conducted for hands on training.

 

4th  Day - Consequence Analysis Requirements in QRA

The theory and practical applications of consequence assessment methods are the focus of this lecture, featuring participation in several workshops to gain experience in practical application of consequence analysis methods, such as

·        Source term modeling (release rate, pool formation and evaporation, and aerosol formation methods)

·        Atmospheric dispersion modeling (meteorological concepts, passive and dense vapor cloud dispersion methods)

·        Fire modeling (pool fire, jet fire, boiling liquid expanding vapor explosion [BLEVE] fireball, and flash fire methods)

·        Explosion modeling (vessel rupture, vapor cloud explosion, and confined explosion methods)

·        Correlations for evaluating personnel injury and facility/equipment damage resulting from toxic exposure, fires, and explosions

·        Software available for performing consequence analyses

 

5th Day – QRA in Safety Instrumented Systems

 

The recent development of Safety Instrumented System (SIS) standards in both the US and Europe have sparked a revolution in process control safety thinking.  ISA 84 and IEC 61511 are the fundamental standards for Assessing SIS. This lecture is intended to present an overview of the design, operation and proof testing of Safety Instrumented Systems. Determining Target Safety Integrity Levels through LOPA techniques, QRA and Risk graph methods are highlighted. The many new concepts of Safety Integrity Levels (SIL), Functional Safety, Safety Instrumented Function, Risk Reduction Factor, Proven-in-Use and Control Separation will be defined. Short class participation workshops will be used to reinforce the ideas presented. Fault Tree Analysis is a major tool for QRA. Use of failure rate databases, Quantification of Fault Trees, cut set concepts, case study analysis for risk comparison,, Pitfalls of Fault Tree Analysis Event Tree Models are also an important tool for QRA, particularly in combination with layers of Protection analysis