N.Y. Gen. Bus. Law § 599-B
Any person, firm, association or corporation desiring a certificate of approval of any traffic control device not conforming to the current manual and specifications for a uniform system of traffic-control devices shall submit to the department of transportation one or more sets of each type of device for which approval is desired or such plans, specifications, design information or data that the commissioner may require, in accordance with and together with the fee provided by the rules and regulations promulgated by the commissioner of transportation pursuant to this article. Upon a finding by the commissioner that the use of any such traffic-control device is necessary, because there are no equivalent conforming devices, and because such use is consistent with the safe regulation of traffic on highways within this state, he may issue a certificate of approval for the sale, lease or offer for sale or hire of any such device.
N.Y. Gen. Bus. Law § 599-B