Jurisdictional Questions. In any arbitration proceeding where a question concerning the arbitrator's jurisdiction over the grievance is raised, the arbitrator shall make a separate decision on the question of his jurisdiction. In his decision the arbitrator shall first rule upon the jurisdictional issues and, if he determines that he has no jurisdiction, he shall make no decision or recommendation concerning the merits of the grievance. Nothing contained herein shall prohibit the arbitrator from taking all evidence of the jurisdictional issues and the merits of the grievance in a single hearing.
