(1) If an employer is a corporation or a partnership, the department is not required to serve the employer personally. In such a case, if no officer or partner of a violating employer is present, the department may issue a notice of infraction to any supervisor or managerial employee.

(2) If the department serves a notice of infraction on a supervisory or managerial employee, and not on an officer, or partner of the employer, the department will mail by certified mail a copy of the notice of infraction to the employer or registered agent of the company. The department will mail a second copy by ordinary mail.