Management Systems
What is a Pre-Startup Safety Review (PSSR)?
Vinit Pandey · Published 4 August 2026
In short: A Pre-Startup Safety Review (PSSR) is a documented check confirming that construction and equipment match design intent, safety procedures are in place, and hazard analysis recommendations have been addressed before a new or modified facility is started up.
Key takeaways
- PSSR is the final gate before hazardous materials are introduced to a new or modified facility
- It confirms construction matches approved design, including any field changes via MOC
- PSSR verifies hazard analysis recommendations are actually closed out, not just documented as planned
- PSSR applies to significant modifications of existing units, not only brand-new facilities
PSSR is typically the final gate in a project or modification lifecycle, performed after construction is complete and before hazardous materials are introduced, confirming the facility is actually ready for safe operation rather than merely mechanically complete.
A PSSR checklist generally confirms that construction matches the approved design (including any field changes captured through management of change), that operating and emergency procedures are available and current, and that operators have received required training.
Critically, PSSR verifies that recommendations from the project's hazard analysis studies — HAZOP, LOPA, SIL verification — have actually been closed out and implemented as designed, not just documented as planned actions.
PSSR applies not only to brand-new facilities but to any significant modification to an existing operating unit, since the same risk — starting up before safety-critical items are genuinely in place — applies equally to a modified process line as to a new one.