A dental hygienist who wishes to receive recognition by the Board as being qualified to administer nitrous oxide shall: Hold an active license to practice dental hygiene in this State; and Successfully complete a Board-approved course of instruction as outlined in Regulation .20 of this chapter that documents training of at least 6 hours consisting of at least: 4 hours of didactic classroom training; and 2 hours of clinical training. A dental hygienist shall pass a written and clinical examination administered by the Board-approved course with an overall passing grade of at least 75 percent in both the written examination portion and the clinical examination portion. The Board-approved course of instruction in administering nitrous oxide may be obtained by: A dental hygienist while an undergraduate student in a Board-approved school for dental hygiene that is accredited by the American Dental Association Committee on Dental Accreditation or its successor organization; or A dental hygienist who completes the course offered by an accredited dental hygiene program. In addition to the Requirements outlined in §§A—C of this regulation, an applicant for recognition to administer nitrous oxide shall take and pass the CDCA Nitrous Oxide Examination for Dental Hygienists.