The board shall conduct hearings, with dispatch, for the purpose of hearing evidence relevant to the subject of the dispute, and shall, as soon as practicable, report its findings and recommendations in writing to the chief executive officer of the county, city, town, fire district, or other governmental unit involved, and to any organization of firemen involved. The report shall be concurred in by at least three members of the board. The recommendation shall be advisory only and shall not be binding upon the county, city, town, fire district, or other governmental unit, or upon the members of the fire department involved.