(1) The Board must have an official seal which is kept in the custody of the Secretary.
(2) The affixing of the official seal of the Board must be witnessed and signed by the Chairperson, or in his or her absence, the Deputy Chairperson.
(3) All documents which are executed by the Board and all decisions of the Board shall be signed by the Chairperson or in his or absence the Deputy Chairperson or any other member authorized in writing by the Chairperson to act on behalf of the Chairperson.