The 13 Controlling Criteria
As discussed in Chapter 1, FHWA has identified 13 design criteria as having substantial importance for the safe and efficient operation of highways. A formal design exception is required if these controlling criteria are not met on the NHS:
Stopping Sight Distance
Lateral Offset to Obstruction
Exceptions to non-controlling criteria should also be identified, justified, and documented, taking into consideration the effect of any deviation from design criteria on safety. The project files should include this information.