Advisers to the Nation on Science, Engineering, and Medicine

The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. On the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Bruce M. Alberts is president of the National Academy of Sciences.

The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. William A. Wulf is president of the National Academy of Engineering.

The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, on its own initiative, to identify issues of medical care, research, and education. Dr. Harvey V. Fineberg is president of the Institute of Medicine.

The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both the Academies and the Institute of Medicine. Dr. Bruce M. Alberts and Dr. William A. Wulf are chair and vice chair, respectively, of the National Research Council.

The Transportation Research Board is a division of the National Research Council, which serves the National Academy of Sciences and the National Academy of Engineering. The Board’s mission is to promote innovation and progress in transportation by stimulating and conducting research, facilitating the dissemination of information, and encouraging the implementation of research results. The Board’s varied activities annually engage more than 4,000 engineers, scientists, and other transportation researchers and practitioners from the public and private sectors and academia, all of whom contribute their expertise in the public interest. The program is supported by state transportation departments, federal agencies including the component administrations of the U.S. Department of Transportation, and other organizations and individuals interested in the development of transportation. www.TRB.org

www.national-academies.org

This reportisthe result ofaprovision inthe1998Transportation Equity Act for the 21st Century (TEA-21) that instructed the Secretary of Transportation to ask the Transportation Research Board (TRB) to conduct a study of the regulations governing the weights, lengths, and widths of commercial motor vehicles operating on highways subject to federal regulation, and to recommend any revisions to the regulations deemed appropriate. These federal regulations, along with state regulations that also limit truck dimensions, have important effects on the costs of highway transportation of freight and passengers.

This study follows a series of investigations of the regulation of commercial motor vehicle size and weight conducted by the U.S. Department of Transportation (DOT) and by earlier TRB committees. The study charge in TEA-21 asked TRB to take into account the conclusions of the 1990 report Truck Weight Limits: Issues and Options (TRB Special Report 225), which was also produced by TRB at the request of Congress. In 2000, DOT published the final version of its Comprehensive Truck Size and Weight Study; the TRB committee that conducted the present study interpreted its task as complementary to the DOT study. The objective of the latter study was to develop an analytical framework that could be applied to assess a range of policy options; the study did not generate policy recommendations. In contrast, the present study provides recommendations, as Congress requested. These recommendations involve organizational arrangements designed to promote reform of the current federal regulations, as well as changes in the regulations to improve the efficiency of truck freight transportation and mitigate the costs of truck traffic to the public.

Unlike the previous TRB and DOT analyses, the present study has not produced new quantitative estimates of the impacts of changes in the regulations. The available models were fully exercised in previous studies, and it was not practical for the committee to develop new

methods. The committee based its conclusions on the evaluations in past truck size and weight studies and criticism of those studies, on other published information sources, and on the comments of interested parties solicited by the committee in accordance with its charge.

The study charge in TEA-21 was broad, encompassing in principle every aspect of a complex body of federal regulations. It was not possible for the committee to review each provision of the regulations individually. Therefore, the absence of a recommendation to change any particular regulatory provision does not represent the committee’s endorsement of the provision. Nor was the objective of the study to identify an optimum set of federal size and weight limits. Rather, the committee’s recommendations relate primarily to the process by which federal regulations are established and the relationship between the federal and state governments in regulating truck size and weight. As one example, the committee did not consider whether federal axle weight limits should be changed. Also, although the committee received comments from members of the motor coach industry that included proposals for regulatory changes, the committee did not evaluate provisions of the federal regulations as they affect passenger coaches in particular.

The study was managed by Joseph R. Morris, who drafted this report under the direction of the committee and under the supervision of Stephen R. Godwin, Director of TRB’s Studies and Information Services Division. Thomas J. Hillegas prepared background material for the committee on enforcement of truck regulations and on methods of mitigating the effects of truck traffic. Suzanne Schneider, Associate Executive Director of TRB, managed the report review process. The report was edited and prepared for publication under the supervision of Nancy Ackerman, Director of Reports and Editorial Services. Rona Briere edited the report, and Alisa Decatur prepared the manuscript for publication. Jocelyn Sands directed project support staff. Special thanks go to Frances E. Holland for assistance with meeting arrangements, communications with committee members, and report production.

This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the National Research Council’s Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making the published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence,

and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process.

Appreciation is expressed to the following individuals for their review of this report: Kenneth L. Campbell, Oak Ridge National Laboratory, Oak Ridge, Tennessee; Thomas B. Deen, Stevensville, Maryland; Edward Fain, Arkansas State Highway and Transportation Department, Little Rock; Gongkang Fu, Wayne State University, Detroit, Michigan; David A. Galt, Montana Department of Transportation, Helena; Patrick McCarthy, Georgia Institute of Technology, Atlanta; Fred P. Nix, Orangeville, Ontario, Canada; and Kenneth A. Small, University of California, Irvine. Although the reviewers provided many constructive comments and suggestions, they were not asked to endorse the findings and conclusions, nor did they see the final draft before its release.

The review of this report was overseen by Christopher A. Sims, Princeton University, and Lester A. Hoel, University of Virginia, Charlottesville. Appointed by the National Research Council, they were responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution.