Section 28-408.6.6. Supervision

The master plumber shall conduct his or her
  business to provide direct and continuing supervision in accordance with
  the provisions of this code.
     Exception: The provisions of this section 28-408.6.6 shall not  apply
  to minor alterations or ordinary repairs, as defined in this code, or to
  the  installation  or  alteration  of  gas  service piping and gas meter
  piping, including meters, valves, regulators or related equipment,  when
  such  work  is  to  be  performed,  serviced  and  maintained by utility
  corporations subject to the jurisdiction of the New  York  state  public
  service commission.