Section 24-227. Circulation devices

(a) No person shall operate or permit to
  be  operated  a circulation device in such a manner as to create a sound
  level in excess of 42 dB(A) when measured inside  a  receiving  property
  dwelling unit. The measurement shall be taken with the window or terrace
  door  open  at a point three feet from the open portion of the window or
  terrace door.
    (b) On and after the effective  date  of  this  section,  when  a  new
  circulation  device  is  installed  on  any  building lot or an existing
  device on any building lot is replaced, the cumulative  sound  from  all
  circulation  devices  on  such  building  lot owned or controlled by the
  owner or person in control of the new  device  being  installed  or  the
  existing  device being replaced shall not exceed 45 dB(A), when measured
  as specified in subdivision a of this section. For a period of two years
  after the effective date of this section,  this  subdivision  shall  not
  apply  to  the replacement of a circulation device that was installed on
  any building lot prior to the effective date of this section by a device
  of comparable capacity.
    (c) Except as otherwise provided in subdivision  b  of  this  section,
  with  respect to circulation devices installed on any building lot prior
  to the effective date of this section, the sound level limit of 42 dB(A)
  referred to in subdivision  a  of  this  section  shall  apply  to  each
  individual  device  except that if the cumulative sound from all devices
  owned or controlled by the same person on  a  building  lot  exceeds  50
  dB(A),  when measured as specified in subdivision a of this section, the
  commissioner may order the owner or person in control of such devices to
  achieve a 5 dB(A) reduction in such cumulative sound  level  within  not
  more than 12 months after the issuance of such order.