U.S. Department of Transportation
    Federal Highway Administration
    1200 New Jersey Avenue, SE
    Washington, DC 20590
    202-366-4000
Federal Highway Administration Research and Technology
      Coordinating, Developing, and Delivering Highway Transportation Innovations
| FACT SHEET | 
| This fact sheet is an archived publication and may contain dated technical, contact, and link information | 
|  | 
| Publication Number: FHWA-HRT-21-078 Date: July 2021 | 
| Publication Number: FHWA-HRT-21-078 Date: July 2021 | 
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