2021 AIChE Spring Meeting & 17th GCPS Short Courses

Location: Virtual TBD

Price: $500

Instructor: Arthur (Art) M. Dowell, III, P.E. & William Bridges 

Book: No Book 

Cancellation Policy: No refund after (11:59 PM Eastern Standard Time) April 15, 2021 

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 Layer of Protection Analysis (LOPA) 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. 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 will also bring you up-to-date on changes from the newly released Guidelines for Initiating Events and Independent Protection Layers, CCPS/AIChE (Mr. Bridges, the instructor, was the primary author of this textbook).

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 and How to systematically create risk scenarios
• How to establish risk acceptance (risk tolerance) criteria for use within your company (this is also called development of ALARP criteria)
• How to calculate “as-is” risk for a cause-consequence pair: Estimate the frequency of the initiating event and estimate consequence
• What is meant by “independence” and “uniqueness” with respect to IPLs
• 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)
• 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 quantifying risk using QRA methods • 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 and 0.8 CEUs or 8 PDHs

Typical Course Candidates

This course is designed for experienced PHA/HAZOP leaders. Other individuals with a strong technical background (such as engineers and scientists) may attend:

• Managers of Operations, Safety; Project Managers; Engineers – Process, Safety, and Mechanical; PSM Coordinators and Managers

Course Outline

1-Day (9:00 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? When is LOPA used?

Developing LOPA Scenarios

• Selecting candidate scenarios from brainstorming hazard evaluations
• Scenarios from design questions and from incidents

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
• 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 (PFOD); How to develop an IPL look-up table
• Workshop 1: Deciding which safeguards are valid IPLs and estimating the PFOD 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
• Workshop 1: Calculating the risk of a LOPA scenario (part of a continuing example)

Judging the Risk

• Examples of risk tolerance criteria from the industry
• Development and implementation of a company risk tolerance criteria
• Workshop 1: Judging the risk of a LOPA scenario (cont. example)

Special Applications of LOPA

• Using LOPA for facility siting questions; Selecting the SIL for an interlock