Aging offshore infrastructure—particularly in mature basins such as the North Sea and Gulf of Mexico—faces escalating integrity management challenges as assets operate well beyond their original design lives. While Risk-Based Inspection (RBI) has become the industry standard for prioritizing inspection efforts, a critical gap persists: conventional RBI implementations often lack a formal, auditable mechanism to leverage high-confidence data from advanced non-destructive testing (NDT) methods to dynamically optimize inspection intervals. This paper addresses that gap by proposing a structured governance framework that systematically integrates quantitative evidence from advanced NDT—such as phased array ultrasonic testing (PAUT), robotic corrosion mapping, and drone-based metrology—into the RBI reassessment process. The methodology comprises three core steps: (1) updating the Probability of Failure (PoF) by incorporating measured degradation rates and revising inspection effectiveness factors to reflect the superior Probability of Detection (POD) of advanced NDT; (2) quantifying epistemic and aleatory uncertainties through probabilistic methods such as Monte Carlo simulation to establish confidence bounds on the revised PoF; and (3) subjecting the technical findings to formal review by a cross-functional governance panel against predefined risk acceptance criteria. The framework’s efficacy is demonstrated through two real-world case studies: one involving external corrosion under insulation on a topside pressure vessel, and another addressing a fatigue crack indication in a subsea pipeline girth weld. In both cases, high-fidelity NDT data enabled defensible inspection interval adjustments—extending the interval by two years in the first case and transitioning to a targeted monitoring strategy in the second—while ensuring PoF remained within corporate and regulatory risk thresholds. The study delivers a transparent, repeatable, and regulatorily defensible methodology that empowers operators of aging assets to replace rigid, calendar-driven inspection schedules with evidence-based, risk-informed decisions, thereby enhancing safety assurance, operational efficiency, and compliance.
Keywords: Advanced Non-Destructive Testing (NDT), Aging Offshore Assets, Inspection Interval Optimization, Probability of Detection (POD), risk-based inspection (RBI)
