Engineers can meet the requirements for direct supervision for implementation of traffic control for state force maintenance projects through training of maintenance staff and District operating procedures. District operating procedures can vary from training maintenance staff in the proper selection of standards and placement of devices in accordance with the standard, to developing modified standard or new project specific traffic control plans SSD by the responsible engineer. Any markings to modify a standard or sketch used for a traffic control layout must be done under the direct supervision of the responsible engineer and must be SSD.