by law or regulation or as may  be specified by the chief or head of the office or other person in lawful authority over them. aTEHCc The circumstance that the duties of any subordinate officer or employee are specified by law shall not, in the absence of special restriction, be understood to prevent his being assigned to additional duties by proper authority, when not inconsistent with  the performance of the duties imposed by law. SECTION  296 . Acting Chief of Bureau . — The assistant chief shall serve as acting chief during the absence or disability of the chief of a Bureau. If there be more than one assistant chief of equal rank, the Department head shall designate the particular on e to supply the place in question, in the absence of special provision therefor. If there be no assistant chief, the Department head may designate any officer or employee of the Bureau or other officer in the service as such acting chief; and for the good  of the service any officer or employee of the Bureau or other officer in the service may be so assigned even though there should be an assistant chief. EHSAaD [1407-37; 1698-15.] SECTION  297 . Designation of Acting Head of Office by Governor-General . — During the temporary absence or disability of the head of any Office or branch of the service, not in or subordinate to a Bureau, the Governor-General may, in the absence of special p rovision, designate any officer or employee to fill his place. HICSTa [See 1698-15.] SECTION  298 . Performance of Duties of Subordinate Officers Temporarily Absent . — In case of the temporary absence or disability of any subordinate officer or employee in any Bureau or Office, the chief of such Bureau or Office may, in the absence of special  provision, designate any other subordinate officer or employee in his Bureau or Office temporarily to perform the duties of the person thus absent or disabled, or he may temporarily perform such duties himself. [1698-15; Comp., 696.] SECTION  299 . Filling of Vacancies . — Vacancies caused by the death, resignation, or removal of any officer or subordinate may be temporarily supplied in the same manner as in case of absence or disability. Such vacancies shall not be filled by permanent ap pointment until the expiration of any leave allowable to the predecessor, unless the Governor-General or proper head of Department is of the opinion that the exigencies of the service require that the appointment be made Copyright 2012 CD Technologies Asia, Inc. and Accesslaw, Inc. Philippine Law Encyclopedia 2011 101