Upgrading from Just HAZOP to HAZOP/LOPA

Many companies have begun upgrading the process hazard analysis (PHA) aspects of PSM from HAZOP to a combination of HAZOP/LOPA. This has resulted in improved hazard analysis and risk evaluation, but has also come with some challenges. This paper will discuss the authors’ experiences and observations in upgrading the analysis. Aspects will include:

• What is needed to upgrade from HAZOP to HAZOP/LOPA.
  • More than just the decision to “upgrade”.
  • Training of facilitators.
  • More detailed PSI – information about safeguards/protection layers.
  • Training of facility management in what to expect – i.e., what was “good enough” before may no longer be “good enough.”
• Benefits of upgrading
  • More thorough analysis of system safeguards
  • More detailed examination of consequence scenarios
  • Improved understanding of processes
  • Increased worker/workplace awareness
  • More critical evaluation of “soft” safeguards
• Challenges of upgrading
  • Increased resources to conduct better analyses
  • Determining which scenarios to conduct LOPA
  • True understanding of LOPA requirements (independent, verifiable, auditable)
  • Realization of inadequacy of some existing safeguards
  • Preparing management for the results – i.e., what was “good enough” before may no longer be “good enough.”