Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter.
Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 2
3
CHAPTER ONE
INTRODUCTION
BACKGROUND AND PROBLEM STATEMENT (CMVs) in Australia, Europe, and North America. The objec-
tives of this synthesis are to document current knowledge and
Speed limiters (also described as speed governors) are devices state of practice for speed limiters in commercial vehicle
that interact with a truck engine to only permit the attainment operations and to survey truck and intercity and charter bus
of a pre-programmed maximum speed. They have been used carriers who have experience in using speed limiters regard-
in Europe and Australia for more than a decade to limit the ing perceived benefits and/or drawbacks. The synthesis also
speed of large trucks and are currently widely available in the identifies additional research needed to better understand key
United States on late model and new Class 8 trucks. Many questions with regard to the safety benefits of speed limiters.
truck fleets use speed limiters for their safety contribution as
well as to reduce fuel use and tire wear, with the speed set at a
APPROACH
level optimum for these factors.
The first step in the study was an extensive literature review to
From a safety perspective, the premise is that by slowing
identify previous studies on this topic. The results of the liter-
down large trucks the travel risks for all motorists may be
ature review were assimilated to address the core question of
lowered by reducing the number of collisions and mitigating
what might be learned from such earlier work, as well as the
the severity of those that do occur. The counter-argument is
methodology and validity of reported results. This process pro-
that safety can be compromised because speed-limited vehicles
vided a foundation for designing a survey of trucking industry
cannot accelerate to avoid traffic conflicts (e.g., in merging
professionals addressing key speed limiter issues. These tasks
situations), and the slower speed of these vehicles relative to
led to the formulation of conclusions and potential next steps.
the surrounding traffic creates speed differentials that have
been correlated with increased crash risk.
In early 2007, before the beginning of this CTBSSP proj-
ect, the American Transportation Research Institute (ATRI)
As described in the body of this report, there is controversy
independently initiated a review of speed limiters, including a
within the trucking industry as to the safety effectiveness of
review of related safety studies and a survey of motor carriers.
speed limiters. This controversy has been heightened by an
The synthesis team coordinated its efforts with ATRI and
initiative to mandate the use of speed limiters in Ontario, as
incorporated relevant information and survey results to maxi-
well as the other Canadian provinces, and the active advocacy
mize commercial truck carrier response and avoid duplicative
of a speed limiter mandate in the United States by the ATA
efforts (McDonald 2007).
and other organizations. The NHTSA is currently evaluating
responses to a Request for Comments on such a mandate.
A further source of perspective and insight in the overall
process was provided by reviews of the preliminary results
With this in mind, the CTBSSP initiated this project to
by the TRB CTBSSP Program Panel.
synthesize data, research, and analyses performed to date in
terms of both the methodologies employed to assess speed
limiters and the actual results, which may be used to guide Literature Review
policy development in North America. This synthesis can
The Study Team performed an extensive literature search to
also provide a foundation for further developments in the
identify information available on the safety impacts of speed
application of speed limiters to commercial vehicle operations.
limiters installed on commercial vehicles and/or buses, empha-
In addition to synthesizing previous studies, a convenience
sizing commercial vehicle operations in North America,
survey of trucking industry stakeholders was completed within
Europe, and Australia.
the project to gain a qualitative view of speed limiter use,
adverse consequences, and perceived effectiveness in safety,
A search process for the literature review was conducted
fuel efficiency, and tire wear.
using a variety of online databases and search engines. Major
information sources for the literature review included:
OBJECTIVES AND SCOPE
· FMCSA research publications
The project scope encompasses studies assessing the safety · ATRI and other industry research and information
effectiveness of speed limiters for commercial motor vehicles publications
