U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
Definition: Length of deceleration lane, not including taper. For tapered ramps, this would be measured from the point where the ramp lane width becomes 12 feet to the point of curvature of the initial ramp curve. For parallel ramps, this would be measured from end of taper to nose of painted gore.
See Figure 21 for additional detail.
HPMS/Tool Requirements: None
Figure 21. Illustration of Deceleration Lane Length for Tapered and Parallel Designs.