Acts not to be invalid-dated by informality, vacancy etc

No act done or proceeding taken under this Act by the Board shall be invalid merely on the ground that -- (a) there is any vacancy or defect in the constitution of the Board; or (b) there is any defect or irregularity in the appointment of a person, who is acting as a member thereof; or (c) there is any defect or irregularity in such act or proceeding, not affecting the substance.