CER issues a Safety Advisory about inconsistencies in pipe dent evaluation and assessment

June 19, 2025

The CER has identified two distinct issues related to the evaluation and assessment of pipe dents. These issues could compromise pipeline operations' safety and harm the environment. The CER works to ensure that all energy infrastructure under our watch is safe and secure and that the environment is protected.

Firstly, a method used for assessing dent fatigue life in American Petroleum Institute (API) Recommended Practice (RP)1183 has been found to have inconsistencies in its screening methods and may potentially underestimate the severity of dents. Secondly, there are inconsistencies in the assessment of dents between the construction and operational phases of pipelines within the Canadian Standards Association (CSA) Z662 Oil and gas pipeline systems (Z662) standard, with less stringent rules applied during construction.

The CER expects companies to:

  • Review and reassess pipeline dents previously considered not to pose a threat to pipeline integrity based on the conservative estimates in Table 6 of API RP 1183 (First Edition), using alternative industry–recognized screening or assessment methodologies.
  • Review and update companies’ dent evaluation procedures for dents identified during manufacturing and construction, aligning them with the more rigorous criteria of Clause 10 in CSA Z662. This review should ensure that operational considerations, including the potential impact of pipeline operation on dent acceptability, are incorporated.
  • Implement a robust system for tracking and recording dent acceptance decisions made during manufacturing and construction. This system should enable location identification of these dents once the pipeline is in operation, facilitating accurate reassessment and monitoring if required.

While there have been no reported incidents related to these issues, this proactive measure Safety Advisory serves to advise regulated companies to re–evaluate past assessments and adopt updated criteria for future evaluations to address discrepancies in dent assessment criteria, ensuring alignment with industry best practices.

Safety Advisories are issued to inform the oil and gas industry of an identified safety or environmental concern, with the goal of preventing incidents. They highlight CER requirements while also conveying the CER’s expectation on how regulated companies must act to mitigate potential impacts on people or the environment.

The CER will continue to follow up with regulated companies to ensure they comply with all our requirements.

For more information, please see the Safety Advisory. (Safety Advisory SA 2025-01 – Evaluation of Dents in Pipe)

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