Question: Fifty Casings in One Region: If an operator places all of their cased crossings in one region regard-less of specific differences in casings based on the pre-assessment data, is this always wrong?
Answer: Under certain circumstances, placing all of the cased crossings in one region may not be inherently wrong, but there would need to be engineering justification for doing so in order to demonstrate that all cased crossings meet all criteria associated with the region definition in accordance with NACE RP 0502-2002 § 3.5. The operator should evaluate the 17 guidance points for selecting regions, and document a technical justification for not establishing regions as described in the guidance (especially with respect to the specific factors that require different regions). If an engineering justification is not documented, additional regionalization must be performed in order for the assessments to be considered valid under the standard. The documented engineering justification must be available for inspection.