Layers of Protection Analysis (LOPA) for Process Safety Management (PSM)

Details :

LOPA is used to comply with the IEC 61511 / ISA 84 standards. IEC 61511 / ISA 84 requires the allocation of safety functions to protection layers, the determination of required Safety Instrumented Functions (SIFs) and the determination of their Safety Integrity Levels (SIL). LOPA is one method used for this purpose. The required SIL of a SIF is derived by taking into account the required risk reduction to be provided by that function. IEC 61511 / ISA 84 notes that this is best accomplished as part of a process hazards and risk analysis (i.e. a PHA) to benefit from possible synergies and the information developed.

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 the more the safer. This can be a false assumption. 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.

This course describes each step in performing LOPA and provides experience in its use. A detailed manual is provided for use as a reference after you have completed the course. Also provided are Microsoft Excel and PHA Works® templates for conducting LOPA studies.

Learn how to perform a LOPA study to evaluate the effectiveness of process safeguards.

Process safety personnel, PHA analysts, control systems engineers, project engineers and others who need to apply or understand LOPA.

Course Contents

  • Process Safety Concepts
  • Overview of LOPA
  • Use of LOPA
  • Documentation and example application
  • Selection of hazard scenarios
  • Definition of scenario consequences
  • Identification of initiating events
  • Consideration of enablers
  • Identify IPL's
  • Estimation of scenario risk
  • Failure data
  • Making risk decisions
  • Remaining Steps
  • Understanding protection layers
  • IPL documentation
  • Implementation
  • Conducting PHA to facilitate LOPA
  • Other uses of LOPA


  • All lectures are in colorful presentation
  • All lectures are interspersed with interactive discussion
  • All lectures include group discussion, case history and exercises
  • Actual major incidents as well as industry experience are reviewed
  • Participants receive a multicolor course manual
  • Pictures of real incidents and case history are shown
  • Videos on the subject are shown

daily 09:00 – 14:00