NOTES: This map should not be interpreted as the official National Network and should not be used for truck size and weight enforcement purposes. “Other NHS” refers to NHS mileage that is not included on the National Network. Conventional combination trucks are tractors with one semitrailer up to 48 feet in length or with one 28-foot semitrailer and one 28-foot trailer. Conventional combination trucks can be up to 102 inches wide.
SOURCE: U.S. Department of Transportation, Federal Highway Administration, Office of Freight Management and Operations, 2015.