Why can I use engineering judgment to determine if a Horizontal Alignment warning sign is needed?
Using engineering judgment to determine if a Horizontal Alignment warning sign is needed has come up short in terms of safety performance. 28% of all highway fatalities occur on horizontal curves. A relationship between curve differential speed (speed on tangent minus recommended curve speed) and safety performance has been established and is the basis for the optional, recommended and mandatory application of Horizontal Alignment warning signs in Table 2C-5.
