The certificate shall be produced and shown on request of the conductor or person in charge of the train on which the retired railroad employee is riding. The presentation shall entitle the retired employee to whom the certificate is issued to pass and repass without payment of fare during offpeak times in regular coach service on the corporation's railroads operating passenger service in this State, within the borders of this State; but no certificate shall be valid for passage on interstate trains which do not provide intrastate service, or on extra fare or special purpose trains.
N.J.S. § 27:25-5.3