Course 11: LOPA (Layer of Protection Analysis) – The
Semi-Quantitative Approach to Risk Assessment (2-day)
Courses |
Calendar |
Instructors |
Course Registration |
Private Training |
Coaching
Recommended prerequisites: Attendees should have strong technical
skills and prior training in qualitative hazard evaluation
techniques; prior completion of
Course 8: Process Hazards Analysis Leadership or
equivalent is highly recommended.
Learn from the
co-originator of LOPA who is also the primary author
of the LOPA textbook (2001) and Guidelines for
Independent Protection Layers and Initiating Events
(2012).
Are proposed or existing combinations of safeguards
enough to prevent an accident or mitigate the consequences?
Do you perceive that doing a fully quantitative risk
assessment (QRA) would be over-working the problem? Then
LOPA (Layer of Protection Analysis) is the new tool you need
to learn.
LOPA combines both qualitative and quantitative elements
of hazard evaluation and risk assessment to analyze and
judge the adequacy of existing or proposed safeguards
against process deviations and accident scenarios. It uses
an order of magnitude approach to quantify the likelihood of
causes, likelihood of failure of independent protection
layers (IPLs), and estimate the consequences for chosen
accident scenarios. These approximations are used to
estimate the risk of a scenario.
A key to the success of LOPA is its rules for judging if
protection layers are truly independent. Because of these
rules, LOPA helps the analysts make consistent judgments of
if the risk of scenarios are “as low as reasonably practical
(ALARP)”. This “How To” course is taught by one of the
principal authors of the AIChE/CCPS book, Layer of
Protection Analysis (2001). The course covers all
aspects of how to apply this very useful technique.
Workshops are used as the primary mode of teaching each
aspect of LOPA. You will perform several complete LOPA
before leaving class.
What You Will Learn:
- When and how to use LOPA.
- How to identify which scenarios from a HAZOP or
other qualitative analysis could benefit from LOPA
- How to systematically create risk scenarios for new
processes or for existing processes under change
- How to establish risk acceptance (risk tolerance)
criteria for use within your company (this is also
called development of ALARP criteria) and how to depict
this in a Risk Matrix or in a formula
- How to calculate "as-is" risk for a
cause-consequence pair:
- How to estimate the frequency of the initiating event
- How to determine the consequence for the scenario
(unmitigated)
- Understand what is meant by “independence” and
“uniqueness” with respect to the safeguard layers (IPLs)
- How to calculate the value of each IPL
- How to determine the risk of a LOPA scenario and how
to determine how much further risk reduction (if any) is
necessary
- How to use LOPA to determine the Safety Integrity
Level (SIL) necessary for an instrument IPL (to comply
with the requirements of IEC 61508/61511 for safety
instrumented systems)
- How to document LOPA
- How other companies worldwide use LOPA to:
- Decide which PHA/HAZOP recommendations to reject and
which to accept
- Focus limited resources within mechanical integrity
departments and
operations on what is critical to manage risk to ALARP
- Avoid wasting resources on the added cost and
unproductive sophistication
that often occurs when they instead quantify risk using QRA methods such as
fault tree and event
tree analysis
- Perform specialized risk modeling for facility siting
questions
Take Home:
- Comprehensive course notebook containing
- Examples of risk acceptance and judgment protocols
- Industry examples and solutions to all LOPA workshops
- Certificate of Completion
- 1.4 CEUs & 1.4 COCs
Typical Course Candidates
This course is designed for experienced PHA/HAZOP leaders
and builds on risk judgment skills learned while doing
qualitative risk reviews. However, others who do
qualitative, semi-quantitative, and fully quantitative risk
assessments will benefit from learning this quicker, simpler
method for estimating risk. Only individuals with a strong
technical background (such as engineers and scientists)
should attend. Others who may benefit from this course
include:
- Managers – Operations, Safety
- Project Managers
- Engineers – Process, Safety, and Mechanical
- PSM Coordinators and Managers
Course Outline
Day 1 (8:00 a.m. to 5:00 p.m.)
Introduction to LOPA
- Learning objectives and goals of using the LOPA
technique
- What is LOPA? How is LOPA applied? Definitions
- Where does LOPA fit with other hazard evaluation and
risk assessment methods?
Developing LOPA Scenarios
- Selecting candidate scenarios from qualitative
(brainstorming) hazard evaluations
- Scenarios from design questions and from incidents
- Deciding on the right cause-consequence pair to
define each scenario
Estimating the Consequence of the Scenario
- Using a look-up table of consequence
- Developing a consequence look-up table for your
company
- Alternative methods for estimating consequences
- Workshop 1: Estimating the consequence of a
scenario (part of a continuing example)
Estimating the Likelihood of the Selected Initiating
Event
- Using a look-up table of initiating event categories
and frequencies that has been updated based on the
recent guideline (2012)
- How to develop an initiating event look-up table for
your company
- Addressing enabling conditions and time-dependent
initiating events
- Workshop 1: Estimating the frequency of an
initiating event of a scenario (part of a continuing
example)
Estimating the Probability of Failure of Independent
Protection Layers
- Definitions, rules, and exceptions for giving credit
for an independent protection layer (IPL)
- Using a look-up table of IPL categories and
probability of failure on demand (PFD) that has been
updated based on the recent guideline (2012)
- How to develop an IPL look-up table for your company
- Workshop 1: Deciding which safeguards are valid
IPLs and estimating the PFD of the valid IPLs (part of
a continuing example)
Calculating the Risk
- Using a standardized LOPA worksheet
- Rules for calculating risk for an individual
scenario (LOPA)
- Rules for summing risk of related scenarios (for
special applications)
- Workshop 1: Calculating the risk of a LOPA
scenario (part of a continuing example)
Day 2 (8:00 a.m. to 3:30 p.m.)
Judging the Risk
- Examples of risk tolerance criteria from the
industry
- Development and implementation of a company risk
tolerance criteria (and possible liability issues
related to documenting a risk tolerance criteria)
- Workshop 1: Judging the risk of a LOPA scenario
(part of a continuing example)
Case Studies
- Workshop 2: Performing a LOPA from beginning to
end, given a LOPA scenario
- Workshop 3: Performing several LOPA, beginning
with a set to HAZOP tables and deciding which scenarios
need LOPA
Special Applications of LOPA
- Using LOPA for facility siting questions
- Using LOPA to select the SIL for a safety interlock
- Workshop 4: Estimating the composite risk for
facility siting risk assessment
Planning your path forward with LOPA
More Information
Instructor:
Bill Bridges will be the
instructor for this course. He has taught this course many
times to hundreds of analysts. He was one of the inventors
and first implementers and trainers of LOPA. He wrote one of
the first definitive papers of the topic and he co-chaired
(with Art Dowell III of Rohm & Haas Chemical Company) the
International PSM conference (sponsored by AIChE/CCPS) that
introduced LOPA. He was a principal author of the CCPS
textbook on this topic and he developed the first course on
this topic with experts at ARCO/Lyondell (in 1996). He has
performed dozens of LOPA in real plant settings and is
considered one of the few experts on this topic. He is also
the primary author of the follow-on textbook, Guidelines for
Independent Protection layers and Initiating Events, 2012 (CCPS/AIChE). To find our
more about this course or to check into having this course
taught at your site; contact Mr. Bridges at 1.865.675.3458
or by e-mail at
wbridges@piii.com.
Schedule:
>>
See the Calendar of Publicly Offered Training.
This course can also be taught (either as-is or
customized) at your site. Please contact PII for details
about having our training provided at your site.
Pricing for Public Offerings (per student):
$795.00 USD (for 2-day version) Registration Information: >>
Click here to register for this
course. |