TRB SPECIAL REPORT: REGULATION OF WEIGHTS, LENGTHS, AND WIDTHS OF COMMERCIAL MOTOR VEHICLES

Federal and state regulations govern the weight and dimensions of trucks, buses, and trailers on U.S. highways. The regulations have economic consequences--trucking accounts for four-fifths of expenditures on freight transportation in the United States, and trucking costs are influenced by truck size and weight. Size and weight limits also influence highway construction and maintenance costs and the convenience and safety of highway travel. In addition, the regulations affect international commerce, because Canada and Mexico have different limits, and because international containers often do not meet U.S. standards. In June 1998, in the Transportation Equity Act for the 21st Century, Congress directed the Secretary of Transportation to request the Transportation Research Board (TRB) to conduct a study of the regulation of weights, lengths, and widths of commercial motor vehicles operating on federal-aid highways under federal regulation, and to develop recommendations. This article reviews TRB Special Report 267, which contains the results of the TRB study. The study recommends organizational arrangements to promote reform of federal regulations for commercial motor vehicles, as well as changes to improve the efficiency of freight transportation and to reduce the public costs of truck traffic.