Section 2(99) of the Act defines “Revisional Authority” as an authority appointed or authorized under this Act for revision of decision or orders referred to in section 108. Section 108 of the Act authorizes such “revisional authority” to call for and examine any order passed by his subordinates and in case he considers the order of the lower authority to be erroneous in so far as it is prejudicial to revenue and is illegal or improper or has not taken into account certain material facts, whether available at the time of issuance of the said order or not or in consequence of an observation by the Comptroller and Auditor General of India, he may, if necessary, he can revise the order after giving opportunity of being heard to the noticee.