Atmospheric Above Grade Inspection and Assessment of Corrosion on Steel Electrical Transmission, Distribution, and Substation StructuresAvailable to Purchase

This standard provides requirements to: (1) help utilities identify structures that may be at a high risk for above-grade corrosion; (2) inspect the selected structures; (3) categorize the condition of structures based on corrosion degradation; (4) prioritize structures requiring additional inspection based on those findings; and (5) help identify next steps as required.

This NACE/IEEE joint standard is limited to the inspection and assessment of steel transmission towers, poles, distribution poles, and substation structures, including galvanized and painted mild steel structures, as well as other similar structures. Inspection of below grade and ground-line weathering steel structures is covered by NACE SP21433-2019/IEEE Std 2445-2018.¹

This standard does not address the inspection of below grade corrosion of structure components, guy anchors, or grounding and lightning systems for structures, neither does it provide procedures regarding repair and/or replacement of these structures.

This standard does not provide specific pass/fail criteria. Pass/fail criteria are often determined by structural strength considerations, which are beyond the scope of a corrosion-related standard. Users of this standard are encouraged to develop their own specific set of pass/fail criteria based upon their particular design requirements.

This standard addresses general and localized corrosion.

For the purposes of this standard, the area of inspection is composed of the visible steel portions of the structure. This standard does not include the inspection of internal corrosion of tubular structures.

The definitions of many of the corrosion-related terms used in this standard can be found in NACE/ASTM⁽¹⁾ G193.²

Definitions of key specific terms in this standard are as follows:

• Inspection: visual observation of a structure for signs of damage or corrosion.

• Assessment: the act of judging or deciding the amount, value, quality, or importance of damage and/or corrosion of structures to determine further action such as repair or replacement.

• Qualified individual: a person who meets legitimate knowledge, skill and/or other requirements through documented or otherwise proven education, knowledge and/or experience.