The other provisions of the Vehicle and Traffic Law relating to motor vehicles shall not apply to special purpose construction equipment, such as described in section 401, subdivision 7, paragraph (f) of the Vehicle and Traffic Law, while engaged in work on a restricted highway, except that all such vehicles and equipment shall be kept in safe mechanical operating condition at all times and reasonable caution shall be used to protect the traveling public. However, such other provisions shall apply to those vehicles that normally operate on public highways to transport persons and/or material and are ordinarily considered commercial vehicles.
N.Y. Comp. Codes R. & Regs. Tit. 17 § 155.5