U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
The International Roughness Index (IRI) is one of the most widely used measures of pavement smoothness or ride quality. Pavements with an IRI rating of less than 170 are considered to have an acceptable ride quality, while those with an IRI of less than 95 can be considered to have a good or very good ride quality.
Data Source for Figure 7-1 and Figure 7-2: US Department of Transportation, Federal Highway Administration, Office of Highway Policy Information, Highway Performance Monitoring System
|<< Prev||Contents||Next >>|