scope:

General

This standard presents acknowledged practices for the mitigation of AC and lightning effects on metallic structures and corrosion control systems. The members of NACE TG 025 agreed that criteria for AC corrosion control should not be included in this standard. However, the mitigation measures implemented for safety and system protection, as outlined in this standard, may also be used for AC corrosion control.

This standard covers some of the basic procedures for determining the level of AC influence and lightning effects to which an existing metallic structure may be subjected and outlines design, installation, maintenance, and testing procedures for CP systems on structures subject to AC influence, primarily caused by proximity of metallic structures to AC power transmission systems. However, this standard is not intended to be a design guide or a "how-to" engineering manual to perform AC interference studies or mitigation designs. Its intent is to provide knowledge and understanding.

This standard does not designate procedures for any specific situation. The provisions of this standard should be applied under the direction of competent persons, who, by reason of knowledge of the physical sciences and the principles of engineering and mathematics, acquired by professional education and related practical experience, are qualified to engage in the practice of corrosion control on metallic structures. Such persons may be registered professional engineers or persons recognized as being qualified and certified as corrosion specialists by NACE, if their professional activities include suitable experience in corrosion control on metallic structures and AC interference and mitigation.

This standard should be used in conjunction with the references contained herein.