Transmission substation structure component design / construction and corrosion risk factors, details on inspection findings / evaluations and mitigating actions, recommended actions for future integrity assessments, and recommended structure design and surveillance practices to optimize lessons learned.
There are an estimated 900,000 electric utility steel transmission and distribution structures in North America alone. The majority of these structures were installed between 1950 and 1990. These structures are now an average of about 45 years of age. The age of these structures dictates an inspection and assessment procedure to determine the level of corrosion affecting the above-grade atmospherically exposed portions of this important segment of our infrastructure.
Prior to the publication of this standard, no industry practice existed to help electric utilities determine a prioritized listing of structures to be inspected or that described an inspection and assessment procedure to evaluate above-grade atmospheric corrosion problems.