The board of adjustment shall adopt rules in accordance with the provisions of the ordinance adopted by the municipal governing body. Meetings of the board of adjustment shall be held at the call of the chairman and at such other times as the board of adjustment may determine. The chairman, or in his absence the acting chairman, may administer oaths and compel the attendance of witnesses. The board of adjustment shall be subject to the open meeting laws of the state and all meetings, deliberations and voting of the board shall be open to the public. The board of adjustment shall keep minutes of its proceedings, showing the vote of each member upon each question, or, if absent or failing to vote, indicating such fact, and shall keep records of all official actions, all of which shall be immediately filed in the office of the board of adjustment and shall be public record.