Turnaround Planning

The time period between successive inspections of an equipment item, determined by the RBI risk ranking, the remaining life, and applicable code requirements. API 510/570 set maximum intervals but allow extension based on RBI assessments. The inspection interval must not exceed half the remaining life (for general thinning) and should be set at less than half the P-F interval for condition monitoring tasks.

The comprehensive plan that defines what to inspect, how to inspect, when to inspect, and what to look for on each equipment item. An inspection strategy integrates the RBI risk ranking, the identified damage mechanisms, the appropriate NDE techniques, the CML locations, the inspection interval, and the acceptance criteria into a coherent plan that can be executed in the field.

The postponement of a planned inspection, maintenance activity, or corrective action beyond its originally scheduled date. Deferrals require formal justification (typically an engineering assessment demonstrating that the deferred activity does not compromise safety or integrity), approval by authorized personnel, interim monitoring or compensating measures, and a firm rescheduled date. Deferrals are governed decisions tracked in the deferral register.

A methodology that uses risk assessment to prioritize and plan inspection activities for pressurized and other equipment. RBI combines Probability of Failure (driven by damage mechanisms and equipment condition) with Consequence of Failure (driven by process hazards and safety impact) to rank equipment by risk and allocate inspection resources where they will have the greatest impact on risk reduction.