Section 147. Deputy health officer

The health officer by the authority and
  under the direction of the commissioner of public safety may  appoint  a
  deputy,  to  hold office during his pleasure. He may, when authorized by
  the commissioner and subject to the approval of the  board  of  estimate
  and  apportionment, appoint such other assistants and employ such health
  and sanitary experts as may be required to carry into effect the powers,
  decisions, orders and directions vested in said commissioner and  health
  officer  by  this chapter and otherwise by law. The compensation of such
  deputy, assistants and experts  shall  be  fixed  by  the  commissioner,
  subject to the approval of the board of estimate and apportionment.