Mich. Comp. Laws § 339.6011

Sec. 1011. A registered building official, plan reviewer, or inspector shall renew his or her registration by September 17 of every third year. Reregistration or renewal of an initial registration or provisional registration shall be based on a determination by the appropriate advisory board of all of the following: (a) The applicant's familiarity with any changes to the codes that the applicant seeks to be registered to enforce. (b) The applicant's familiarity with other pertinent laws. (c) Evidence satisfactory to the appropriate board that the applicant has attended local in-service training and education programs on an ongoing basis.