2013 New York Consolidated Laws
VAT - Vehicle & Traffic
Title 7 - RULES OF THE ROAD
Article 28 - (1160 - 1166) TURNING AND STARTING AND SIGNALS ON STOPPING AND TURNING
1164 - Signals by hand and arm or signal lamps.

 
    § 1164. Signals  by hand and arm or signal lamps. (a) Any stop or turn
  signal when required herein shall be given either by means of  the  hand
  and  arm  or by signal lamps, except as otherwise provided in subsection
  (b).
    (b) Any motor vehicle in use on a highway shall be equipped with,  and
  required  signal  shall be given by, signal lamps when the distance from
  the center of the top of the steering post to the left outside limit  of
  the body, cab, or load of such motor vehicle exceeds twenty-four inches,
  or  when the distance from the center of the top of the steering post to
  the rear limit of the body or load thereof exceeds  fourteen  feet.  The
  latter  measurement  shall  apply  to  any  single  vehicle, also to any
  combination of vehicles. On a combination of vehicles, the  rear  signal
  lamps  shall  be at the rear of the last vehicle in the combination. The
  provisions of this subdivision shall not apply to a vehicle, alone or in
  combination with other vehicles or implements, if such vehicle  is  used
  solely  for  agricultural  purposes,  and  is  not designed and intended
  primarily for use on the highway, or to fire  vehicles,  or  to  special
  purpose  commercial  motor  vehicles  registered  under  schedule  F  of
  subdivision seven of section four hundred one of this chapter.