(a) A provision of a section referring to the board, the commissioner, or the fire marshal, or a provision referring to the presiding officer, is construed to apply to the board or the chairman if the matter is within the jurisdiction of the board, to the commissioner if the matter is within the jurisdiction of the commissioner, or to the fire marshal if the matter is within the jurisdiction of the fire marshal.(b) Unless otherwise provided by law, any duty imposed on the board, the chairman, the commissioner, or the fire marshal may be delegated to a duly authorized representative. In such case, the provisions of any section referring to the board, the chairman, the commissioner, or the fire marshal shall be construed to also apply to the duly authorized representative(s) of the board, the chairman, the commissioner, or the fire marshal.