Abstract
The paper presents a phased approach to the quantification of pipeline risk due to corrosion, SCC and other defect- based hazards. Public concern and pressure from regulatory bodies are accelerating the need for pipeline operators to formalize and intensify their approach to integrity management, and there is a growing acceptance of a risk-based approach to the prioritization, planning, and evaluation of integrity assessments.
Varying amounts and quality of data are required to do risk assessments depending on the methodology used and the required outcome. For pipelines not currently on a formal assessment plan, the data available tend to be sparse and qualitative in nature. This level of data quality and availability seldom lends itself to a fully quantitative risk assessment, but is adequate for qualitative and/or semi-quantitative methods, and these methods, in turn, are adequate to address the initial prioritization of integrity assessments. As assessment data become available, the operator can take advantage of risk methodologies that progressively incorporate quantitative data. The phased quantitative methodologies described in this paper incorporate quantitative assessment data that caters to the developing needs of the operators.
Most operators need a phased approach to progressively adopt the most relevant and needed assessments. These organized and relevant steps need to be introduced according to data available and maturity of the integrity management program. Each refinement to the quantification offers distinct advantages to the user. The paper explains these advantages. Corrosion is used as an example, but the approach is applicable to any time-dependent defect based hazard.
