Candidates have four hours to complete an examination.
The examinations are developed and revised by the Board of Directors in consultation with a professional examination service. Examination questions are written by a panel of certified occupational health nurses, are edited by experts in testing and evaluation, and are approved by the Board. The examination content is based on the results of research designed to identify the tasks and knowledge required to practice in the specialty of occupational health nursing. This method has resulted in a valid and highly reliable examination. Several organizations and educational institutions have developed courses and materials to assist individuals in becoming certified.