N.C. Gen. Stat. § 150B-18: Scope and effect.

This Article applies to an agency's exercise of its authority to adopt a rule. A rule is not valid unless it is adopted in substantial compliance with this Article. An agency shall not seek to implement or enforce against any person a policy, guideline, or other interpretive statement that meets the definition of a rule contained in G.S. 150B-2(8a) if the policy, guideline, or other interpretive statement has not been adopted as a rule in accordance with this Article. (1991, c. 418, s. 1; 2011-398, s. 1; 2012-187, s. 2.)