The department upon written notice of at least five days to the permittee, may require the permittee to submit to an examination if the department has good cause to believe that a permittee is incompetent or otherwise not qualified to retain an operator permit. Upon the conclusion of the examination, the department shall take action as may be appropriate and may suspend or revoke the permit of that person or may issue a permit subject to restriction. Refusal or neglect of the permittee to submit to this examination shall be grounds for suspension or revocation of the permit.
Haw. Code R. § 13-251-18