Process Safety Information (PSI)

Definition:
Process Safety Information (PSI) refers to the collection of technical data and documentation required to understand the hazards of a process. While PSI is not a term defined in IEC 61511, it is a formally defined requirement under OSHA’s Process Safety Management (PSM) standard (29 CFR 1910.119.(d)).

In practice, PSI provides the inputs needed to perform hazard & risk analysis (H&RA) one of the earliest steps in the functional safety lifecycle.  Without this accurate documentation of PSI, downstream functional safety work is inherently unreliable.

Key Points:

  • PSI is a regulatory term under OSHA PSM, not an IEC 61511 term.
  • PSI documents the process hazards, process design, and equipment design.
  • PSI is an input into the hazard and risk analysis (H&RA).  It is not a functional safety deliverable.
  • Consists of P&IDs, process chemistry and hazards, design limits, relief system design, equipment specifications.
  • What is not PSI: Safety Requirements Specifications (SRS), SIL calculations, SIL verification reports, or other IEC 61511 lifecycle documents.

Example:
Before performing a HAZOP on a reactor system, the team reviews P&IDs, relief system design, chemical properties, operating limits, and equipment specifications.  This is construed as PSI.   

See Also: PSM, H&RA, OSHA

Cited Source:

Glossary Category

Glossary Catalog