Revision of Thirteen Controlling Criteria for Design; Notice and Request for Comment
The geometric design standards for projects on the National Highway System (NHS) are incorporated by reference in FHWA regulations. These design standards are comprehensive in nature, covering a multitude of design characteristics, while allowing flexibility in application. Exceptions may be approved on a project basis for designs that do not conform to the minimum or limiting criteria set forth in the standards, policies, and standard specifications. The FHWA is updating its policy regarding controlling criteria for design. The current policy identifies 13 controlling criteria for design and requires formal design exceptions when any of the 13 controlling criteria are not met. The FHWA intends to further streamline the controlling criteria, and the application of these criteria, based on the results of recent research that evaluated the safety and operational effects of the 13 controlling criteria. The FHWA also intends to clarify when design exceptions are required and the documentation that is expected to support such requests. This notice solicits comments on the proposed revisions to the 13 controlling criteria for the design of projects on the NHS that require a design exception when adopted design criteria are not met, in accordance with FHWA regulations.