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Proposed Rule

Commercial Vehicle Width Exclusive Devices

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Information about this document as published in the Federal Register.

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Federal Highway Administration (FHWA), DOT.


Withdrawal of proposed rulemaking and closing of public docket.


This document withdraws a proposed rulemaking to amend the Federal Highway Administration (FHWA) regulations to increase by one-inch the distance that width exclusive devices could extend beyond the sides of commercial motor vehicles. The intent of the one-inch increase was to harmonize the United States' width exclusion limits for certain devices with those of Canada and Mexico, as recommended in a draft report of the Land Transportation Standards Subcommittee, created as a result of the North American Free Trade Agreement (NAFTA). The FHWA is unable to determine at this time that there is a need for an increase in the existing width exclusion applicable to safety and energy conservation devices. In addition, there is no evidence that the lack of harmonization is adversely affecting NAFTA implementation or that harmonization in this area is otherwise necessary. Therefore, the FHWA is withdrawing the proposed rulemaking and closing the public docket.

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Mr. Phillip Forjan, Office of Freight Management and Operations (202) 366-6817, or Mr. Raymond Cuprill, Office of the Chief Counsel (202) 366-1377, Federal Highway Administration, 400 Seventh Street, SW., Washington, DC 20590. Office hours are from 7:45 a.m. to 4:15 p.m., e.t., Monday through Friday, except Federal holidays.

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In October 1999, the Land Transportation Standards Subcommittee (LTSS), created by the NAFTA Working Group 2, issued a draft discussion paper. The draft paper, “Highway Safety Performance Criteria in Support of Vehicle Weight and Dimension Regulations” (a copy of which is included in this docket), contained candidate vehicle performance criteria and recommended threshold values. The primary objective of Working Group 2 was to seek areas within the broad range of vehicle weights and dimensions that could be harmonized among the participating countries (Mexico, Canada, and the United States).

The working group's draft discussion paper included the definition of “overall width” and proposed a standard for use by the three countries. This definition described width exclusive devices or appurtenances at the sides of a truck, tractor, semitrailer, or trailer whose function is related to the safe operation of the vehicle. Such devices may extend no more than 10 centimeters beyond the side of the vehicle. (Using accepted conversion factors, 10 centimeters equates to 3.937 inches.) Start Printed Page 62427

In a final rule published March 29, 2002 (67 FR 15102), the FHWA said it was preparing to issue a notice of proposed rulemaking (NPRM) to consider an extension from three inches (the current U.S. exclusion standard) to four inches in the distance that non-property carrying devices could protrude from the sides of commercial motor vehicles. The NPRM was eventually published under FHWA Docket No. 2001-10370 on July 29, 2002 (67 FR 48994).

Because of concerns raised by several respondents to this NPRM, in particular the absence of research on the effects of such an increase, the FHWA determined it appropriate to issue a supplemental notice of proposed rulemaking (SNPRM). On March 12, 2004, the FHWA published an SNPRM requesting further public comment on the proposal under Docket No. FHWA-2003-16164 (65 FR 11997). By issuing the SNPRM, the FHWA sought to obtain information that would document the experience of others in undertaking similar changes to vehicle width exclusion standards or monitoring and evaluating vehicle crashes caused by contact with width exclusive devices. Our goal was to ascertain whether there might be any known operating or safety repercussions that could result from the one-inch increase.

The FHWA received 3 comments in response to the SNPRM. None of these provided any more definitive information to make the required determination that the proposed expansion of the width exclusion is needed to promote commercial motor vehicle safety and efficiency. We received comments from an individual, the Truck Manufacturers Association (TMA), and the Advocates for Highway and Automobile Safety (AHAS).

Discussion of Comments

The individual commented that a Federal rule requiring all States to allow an extra inch on each side of commercial motor vehicles (CMVs) for non-cargo carrying devices on the National Network (NN) and reasonable access routes would be more efficient than each State issuing its own overwidth permits. Nevertheless, she opposed such a rule because issuing a special permit would be different than allowing a whole class of “humongous” vehicles. It appears that her objection was not so much directed at an extra inch for safety or energy conserving devices, but at the overall size of trucks, which is beyond the scope of this rulemaking action.

The TMA stated that the FHWA would be unable to find answers concerning possible effects of allowing the additional inch for excluded devices. It noted that this situation was not surprising, given the “obscure and essentially unresearchable nature of the underlying question—namely, will one inch of additional width of a vehicle, all things else being equal, cause more crashes?” It noted that the proposed change would not increase the width dimensions of the vehicle per se, but only the attached, excludable non-cargo carrying devices. The TMA stated that the change in “encroachments” of these devices would be “extremely small,” would make “researching the crash cause and effect relationship” very difficult, and would “not [be] readily identifiable in crash data bases.” The TMA concluded that, “given the de minimus nature” of the change, and the benefits to NAFTA harmonization efforts, it would support the one-inch increase proposed in the NPRM and SNPRM.

Repeating its earlier objections to the NPRM, the AHAS again opposed the proposal for the one-inch change in the exclusion provisions. Referring to the FHWA's request for information in the SNPRM, it concluded that “the FHWA has acknowledged [in the SNPRM] the need to make a specific safety finding on the safety consequences of allowing an additional inch of width on each side of a commercial motor vehicle.” The AHAS also challenged the FHWA's reliance upon sources claiming no knowledge about the “precise safety effects of vehicle width increases” as an “application of agency expertise.” The AHAS indicated that such reliance would not allow the FHWA to “draw well-crafted and strongly supported conclusions from the facts entered into the record.”

It further noted that the references cited in the SNPRM are no substitute for making “specific safety findings about the consequences of change in policy,” and demanded that the agency employ “empirical” research, rather than rely upon sources that can offer no insight into the safety consequences of the suggested change. The AHAS reminded the FHWA that the requirement for such empirical research grows out of a “statutory obligation to measure the safety impact of such changes” that cannot be satisfied merely by “expressions of ignorance or a priori argument.”

The AHAS further stated that adding an extra inch in the width of excluded devices is not a de minimus change in the current limitation. It also noted that there are many highways on the NN with less than 12-foot wide lanes where the one-inch increase could have safety implications.


The FHWA is unable to determine at this time that there is a need for an increase in the existing width exclusion applicable to safety and energy conservation devices. The administrative record of this rulemaking action has failed to identify any specific devices that would need the proposed expansion of the width exclusion in order to promote commercial motor vehicle safety and efficiency. In addition, there is no evidence that the lack of harmonization is adversely affecting NAFTA implementation or that harmonization in this area is otherwise necessary. Therefore, the FHWA is withdrawing this rulemaking and closing the docket.

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Authority: 23 U.S.C. 127 and 315; 49 U.S.C. 31111 through 31115; 49 CFR 1.48(b)(19) and (c)(19).

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Issued on: October 20, 2004.

Mary E. Peters,

Federal Highway Administrator.

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[FR Doc. 04-23966 Filed 10-25-04; 8:45 am]