40. The fact that any work or thing has been executed or done with the consent of the Port Authority and in accordance with any reasonable conditions or restrictions prescribed by the Port Authority or in accordance with plans approved or deemed to be approved by the Port Authority or to their satisfaction or in accordance with any directions or award of an arbitrator or in accordance with any plans approved by the Secretary of State and any conditions or restrictions imposed by him shall not relieve the undertaker from any liability under the provisions of this Part of this Schedule save where any such liability arises by reason of any conditions or restrictions imposed by the Port Authority.