|
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
|