39. Where an applicant for certificate of competency is reported by the examiners or the Board of examiners to have passed the examination prescribed for the certificate and given satisfactory evidence of his sobriety, ability and general good conduct on board inland ship, the Director-General or such officer as he may appoint in this behalf shall grant the applicant the certificate of competency applied for: Provided that before granting a certificate of competency, the Director-General or, as the case may be, the officer may, if he finds report of the examiners or the Board of examiners in respect of any applicant to be defective or has reason to believe that the report has been unduly made require a further examination or a re-examination of the applicant.