Hearings shall be conducted by a hearing officer who may be a member of the board or a person designated and empowered by the board. The hearing officer shall rule upon matters of procedure and introduction of evidence, and shall conduct the hearing in such manner, in his discretion, as will best serve the purpose of the attainment of justice. Objections may be taken to rulings of the hearing officer, with the reasons given for such objections. After the conclusion of the hearing, the hearing officer shall make, in writing, his findings as to whether the evidence sustains the charges, or any of them, relating to revocation or modification of the certificate of eligibility, and shall designate which charges he has found sustained by the evidence and shall forward such findings to the board. A copy of such report shall be served upon the certificate holder or his attorney by ordinary mail prior to submission of such report to the board, provided a request therefor is made on the record at the hearing. The report, when served, shall be accompanied by a statement in writing advising that the recipient may controvert any of the findings contained therein within the time limited in such statement. The stenographic record of the hearing shall be referred, together with the hearing officer's report, and statement controverting the findings contained therein, for due consideration and appraisal by the board.