Specifications include, but are not limited to: Maintenance hereunder refers to all maintenance necessary to keep the highway lighting systems in normal working order, the types and locations of which are designated in Exhibit “A” hereto attached and made a part hereof. Maintenance of the system is to begin on the low side of the transformer; transformer to be serviced by others. Each highway lighting system was constructed or modified in essential accordance with plans approved by the Department of Transportation. The Kansas Department of Transportation shall repair or replace all damaged sign trusses. Any additions to the highway lighting systems listed in Exhibit “A” during the period of this contract shall be incorporated into this contract. The District Engineer or his representative shall notify the Contractor in writing when additional systems are to be maintained. All work and materials shall conform to the requirements of the Plan Specifications, the regulations of the "National Board of Fire Underwriters," and the requirements of the National Electric Safety Code.