A robust MOC solution incorporates a Pre-Startup Safety Review (PSSR) process step. The PSSR is meant to assure that all punch list items are complete, procedures are updated, and training on the change is conducted prior to startup. PSSR is usually facilitated by a series of checklists that help determine that construction is in accordance with design specs and more simply that bolts are tight, safety showers functional, alarms audible, and a host of other issues all based on the scope of the change. A PSSR can be a standalone activity (i.e., Ad hoc Maintenance).
MOC regulates direct modifications to refining and chemical processes as well as changes that have indirect impact such as personnel changes. It is designed to require change review and approval in order to prevent process safety incidents. Performing MOC well delivers additional payback including fewer unplanned outages since equipment uptime will be increased and startups decreased. MOC is a core framework element for Intelligent Operations leading to Operational Excellence.