Poor: IRI > 170
Fair: IRI 95 - 170
Good: IRI < 95
Pavement condition is measured by the International Roughness Index (IRI) which takes a longitudinal profile of pavement roughness based on one-way facility centerline miles. A lower IRI indicates smoother highway conditions and a higher IRI indicates rougher highway conditions.
Sources:Source: U.S. Department of Transportation, Federal Highway Administration, Highway Statistics, table HM-47, available at https://www.fhwa.dot.gov/policyinformation/statistics.cfm/.
Last Updated: October 2017 | Retrieved: December 2017