xt75x63b2v97 https://exploreuk.uky.edu/dips/xt75x63b2v97/data/mets.xml President's Highway Safety Conference (1949: Washington, D.C.) President's Highway Safety Conference (1949: Washington, D.C.) 1949 v, 70 p.: ill. 24 cm. UK holds archival copy for ASERL Collaborative Federal Depository Program libraries. Call Number: FW 2.18:En 3/1949/prelim. books English Washington: U.S. G.P.O. This digital resource may be freely searched and displayed in accordance with U. S. copyright laws. Works Progress Administration Transportation Publications Traffic safety -- United States Safety education Preliminary Revised Report of Committee on Engineering: The President's Highway Safety Conference, Held in Washington, D.C., June 1, 2, and 3, 1949: Other Conference Committee Reports: Accident Records, Motor Vehicle Administration, Education, Enforcement, Laws and Ordinances, Public Information, Organized Public Support, and the Action Program, 1949 text Preliminary Revised Report of Committee on Engineering: The President's Highway Safety Conference, Held in Washington, D.C., June 1, 2, and 3, 1949: Other Conference Committee Reports: Accident Records, Motor Vehicle Administration, Education, Enforcement, Laws and Ordinances, Public Information, Organized Public Support, and the Action Program, 1949 1949 1949 2021 true xt75x63b2v97 section xt75x63b2v97 .. z . f
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iiPREDELIMINARY REVISED
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REPORT OF ‘COMMITTEE ON
ENGINEERING
The President’s HIGHWAY
SAFETY CONFERENCE.
Held in.
WASHINGTON.D.C.
JUNE 1, 2, and 3, 1949
OTHER CONFERENCE COMMITTEE REPORTS
ACCIDENT RECORDS . MOTOR V EEEEEE ADMINISTRATION
EDUCATION - ENFORCEMENT o LAws AND ORDINANCES
PUBLIC INFORMATION - ORGANIZED PUBLIC SUPPORT
and the ACTION PROGRAM
P eeeee ted by the COMMITTEE ON GO EEEEE NCE REPORTS
1455-53)
Q'SLTITOT DISCARD l
' N
Conference Organization
General Chairman:
MAJ. GEN. PHILIP B. FLEMING
Administrator, F edera] Works Agency
Wrashington, D. C.
Vice Chairmen:
WILLIAM PRESTON LANE, JR.
Governor of Maryland
Chairman, The Covernors’ Conference
GEORGE W. WELSH
Mayor, Grand Rapids, Mich.
President, United States Conference of Mayors
Executive Director:
RUDOLPH F. KING
Massachusetts Registrar of Motor Vehicles
Boston, Mass.
COORDINATING COMMITTEE
Chairman:
THOMAS H. MACDONALD
Commissioner, Public Roads Administration
.‘ j * Washington, D. C.
MAJ. GEN. EDW;ARD H BROOKS Director, Personnel and Administra-
tion, General Staff, U. S. Army.
C. W. BROWN, President, American Association of State Highway
Officials.
J. A. A. BURNQUIST, President, National Association of Attorneys
General-
J USTUS F. CRAEMER, President, National Association of Railroad and
Utilities Commissioners.
M. C. CONNORS, President, American Association of Motor Vehicle
Administrators.
NED H. DEARBORN, President, National Safety Council.
CLYDE A. ERWIN, President, National Council of Chief State School
Oflicers.
WALLACE J. F ALVEY, Chairman, Advisory Group, Accident Preven-
tion Department, Association of Casualty and Surety Companies.
COL. HOMER GARRISON, JR, President, International Association of
Chiefs of Police.
JOSEPH F. HAMMOND, President, National Association of County
Officials.
Dr. R. H. HUTCHESON, President, Association of State and Territorial
Health Officers.
HAROLD P. JACKSON, Chairman, National Committee for Tralfic Safety.
PYKE JOHNSON, President, Automotive Safety Foundation.
C. R. MCCOTTER, President, National Association of Automotive In-
surance Companies, Indianapolis, Ind.
DELESSEPS S. MORRISON, President, American Municipal Association
(Mayor of New Orleans).
CHARLES A. PETERS, Chairman, Federal Interdepartmental Safety
Council.
ROBERT J. SCHMUNK, President, American Automobile Association.
EARL O- SHREVE,‘ President, Chamber of Commerce of the United
States.
COMMITTEE ON CONFERENCE REPORTS
Consists of members of Coordinating Committee, Chairmen of
Conference Committees, Regional Oflicers, and Representatives of
each State.
III
CONTENTS
General aspects ____________________________________________________
Accident factors _______________________________________________
Responsibility of the highway administrator _______________________
Responsibility of the engineer ___________________________________
The engineering attack _________________________________________
Opportunity to improve engineering contributions to safety ________
Value of research ______________________________________________
Effect of legal and regulatory provisions __________________________
Assuring continuity of high-grade highway-transportation engineering-
The highway ______________________________________________________
Long-range planning means safer highways _______________________
Relation of highway design and accidents _________________________
Importance of highway design ___________________________________
Salient provisions of the design policies ___________________________
Interstate highway standards ___________________________________
Safety benefits from improved highway design _____________________
Safety design on low—volume highways ___________________________
Need for street improvements within communities _________________
Application of safe-design principles in actual construction programs__
Good maintenance necessary for safety __________________________
The operation _____________________________________________________
Need for factual data __________________________________________
Engineering analysis of traflic accidents __________________________
Speed ________________________________________________________
Speed zoning __________________________________________________
Effect of restrictions on vehicle sizes and weights __________________
Influence of traffic and roadway conditions on safe vehicle operation-
Traflic-control devices and techniques _________________ v ___________
Highway—railroad grade-crossing protection _______________________
Pedestrian control _____________________________________________
One-way streets _______________________________________________
Segregation of vehicle types by lanes and roadways ________________
Modern street and highway lighting ______________________________
Channelization ________________________________________________
Intersection control ____________________________________________
Through—street systems _________________________________________
Unbalanced-lane flow __________________________________________
Relation of parking provisions to safety __________________________
Protection of the roadside ______________________________________
T ransit-vehicle stops ___________________________________________
Truck-loading zones and terminals _______________________________
The vehicle _______________________________________________________
General safety policy ___________________________________________
Dependability of the modern automobile _________________________
Résumé of principal safety developments _________________________
Criticisms of vehicle design _____________________________________
Motor-vehicle inspection ________________________________________
Maintenance of vehicles ________________________________________
Recommended action program ______________________________________
Committee on Engineering __________________________________________
V
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Report of Committee on
Engineering
GENERAL ASPECTS
Since the President’s Highway Safety Conference of 1946, the urban
and over-all traffic-fatality rates have declined. The rural rate has
risen, however. And the over—all trend reversed in the early months
of 1949—the fatality rate was higher during the first quarter of the
year than in the same period of 1948. This reversal and the alarming
annual accident toll as well constitute a pressing challenge to the
engineering profession.
Engineers have been striving for many years to provide vehicles,
roads, and operational control that will enable private motorists,
commercial—vehicle operators, passengers in public conveyances, and
pedestrians to reach their destinations conveniently and safely.
Highway, automotive, and operations engineers alike have given
special attention to two considerations—human behavior and physical
conditions of the highway and the vehicle. Their joint efforts are
paying significant dividends in the saving of lives and the prevention
of 1njuries and property damage.
A far more intensive use of motor transport 1S certain 1n the future.
To accommodate the mounting traflic volumes by superimposing ade-
quate and safe transportation arteries on the existing street patterns
Will continue to be exceptionally diflicult and costly in metropolitan
areas. Yet it is likely that the creation of these arteries, plus greater
use of public transit, will be necessary if cities are to be maintained
as economically sound units.
Accident Factors
Causes of street and highway accidents lie in human behavior and
in external conditions. The latter are particularly susceptible to
engineering attack. To the extent that changes in external conditions
can make human errors and m1s3 udgments less likely and less hazard-
ous, this approach will have success.
Drivers who have more than their share of accidents are rare,
for accident-prone individuals are comparatively few. It is among
the great bulk of drivers Who ordinarily use reasonable care that
nearly all accidents occur. They happen more or less at random
among the driving population, involve every conceivable kind of person
' 1
with every degree of driving skill, and take place in every imaginable
way. To this majority of reasonably careful drivers, engineering im-
provements offer great promise of accident reduction.
Obviously engineering control methods cannot make roads and
vehicles foolproof, nor proof against reckless or criminal acts, nor
totally immune from accidents. Emphasis should, therefore, be on
engineering that will increase safety for the mass of good, bad, and
indifferent drivers who have no especial proneness to accidents nor
criminally reckless tendencies.
Accidents may occur under any set of conditions. But if vehicles,
roads, and control procedures and devices are designed to fit conditions
of use and known patterns of human behavior, physical conditions
will be provided under which, it is not too much to expect, accident
frequency and severity will be greatly reduced. In furthering desir-
able physical conditions, traffic—control devices such as those prescribed
in the Manual 011 Uniform Traflic Control Devices are of great value
and reasonably adequate. Where their use is warranted from an
engineering standpoint, they are recommended. It must be remem-
bered, however, that when misused, they cause irritation, delay, con-
gestion, and accidents. This equipment, furthermore, is of little benefit
without public understanding and support or without enforcement of
attendant regulations.
Responsibility 0 f the Highway Administrator
An appraisal of the existing organizational structure and its func-
tions should be made by the highway administrator to determine
whether the necessary sustained program of engineering analysis of
. traffic accidents is being efficiently and effectively conducted. The
appraisal-should reveal whether the highway department (State 01‘
local) is so organized that:
1. Every serious accident is analyzed to see whether any road feature
or deficiency contributed to it.
2. The results of the analysis are applied to the correction of the
condition.
3. The results are also considered in relation to design standards and
practices, maintenance practices, and traffic regulation and control.
Engineering analysis of all serious accidents requires an adequate
unit in the department charged with this function, and the closest
possible liaison between this unit and the units responsible for design,
maintenance, and operations.
Generally better coordination and cooperation between highway and
enforcement departments also are needed. The highway administra-
tor can advantageously help to perfect a closer liaison. Periodic .
conferences, for example, have proved of inestimable benefit to both
agencies for the discussion of mutual problems. Properly instructed,
2
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the police can do many things—such as enforcement against over-
weight and oversize—to conserve highway investment and insure
effective safe highway use.
The collection and analysis of accident records plays a fundamental
role in the success of several phases of safety effort. The highway ad-
ministrator has an obligation to cooperate with enforcement officials
and others in seeing that a qualified agency performs this function.
Since in many States the initial investigation and reports are made by
the police, it is highly desirable that the special needs of the engineer as
to precise accident location and other roadway and traffic details be
recognized by the police and the agency responsible for collection and
analysis of accident records.
Responsibility of the Engineer
The responsibility of the engineer for efficient and safe highway
transportation is far greater than has generally been realized, even
by many engineers. Indeed no profession can do more for highway
safety—and few can do as much.
The engineer’s responsibility is to provide roads and vehicles safe
for reasonable use. The motor-vehicle driver is entitled to a factor
of safety that will give him substantial protection against hazards over
which he has no control—hazards such as the acts of other drivers
and of pedestrians, physical features of the highway and vehicle that
limit visibility or otherwise endanger the traveler, inadequate signing,
and uncontrolled or unrelieved congestion.
A typical problem in safe highway design concerns vehicle speeds.
Important basic design data are the speeds at which reasonable
drivers will operate under good driving conditions. It has been
found for instance, that when the only limitations on speed are
the capability of the machine and the desire of the driver, the great
majority of drivers want to make “good time” but only about 15
percent exceed a reasonable and safe maximum speed. Under these
conditions speeds range from 25 to 80 miles per hour, but only 15
percent exceed 55 miles per hour and only 13 percent go slower than
35. The average speed is 454 The application of data of this type
to road design is one engineering approach to safety.
A major possibility for traffic-accident reduction through safety
engineering lies in making highway use safer during the hours of
darkness. Though less than a third of the travel is at night, about
65 percent of the traffic fatalities and 48 percent of all traffic acci-
dents occur after dark. More adequate street and highway lighting at
properly selected locations, and better vehicle lighting, would pay
large dividends in the saving of lives and reduction of property
damage.
837403—49—2
Fortunately engineering leaders are now giving greatly increased
emphasis to their inescapable responsibility for safe and efficient
highway transportation.
A recent publication, Traffic Engineering Functions and Adminis-
tration,1 prepared by a Joint Committee representing the American
Association of State Highway Officials, The American Public Works
Association, and the Institute of Traffic Engineers, is a most valuable
guide to efi'ective engineering and administrative practice in the
traffic field.
The Engineering Attack
The engineering approach to highway safety is high-lighted by long—
range planning and orderly annual programs of highway improve-
ment, maintenance, operation, and administration so that lasting
results can be achieved, beginning at the earliest possible moment.
In planning highway improvements, determination of the type of
highway to be built in any given location depends fundamentally on
traffic requirements and funds available. For thousands of miles of
roads, the immediate complete improvement is beyond the capacity
of the public purse; yet in congested regions, reasonable taxes—if
used for highway purposes—can provide multilaned, divided road-
ways, grade separations, controlled access, lighting, and all the j ustifi-
able safety features yet devised.
Because roads and streets can be made much safer through the
application of safety-engineering technology, the most feasible road-
engineering solution to the accident problem is to build into a road,
Within the limit of available funds, all the proved safety features
applicable to its type or class. And the ideal time to do this is during
the original construction stage.
This will involve due attention to available facts concerning both
prevailing and anticipated driver behavior and vehicle characteristics.
The resulting improvements needed for safety will range from treat-
ment of specific, hazardous spots on existing improved roads, to new
construction of controlled—access express highways.
But since all roads and streets cannot be made foolproof through
engineering design, the engineering solution that may be used most
extensively at present is control of traffic operations through regula—
tion of road usage. This method consists of the proper use of signs,
signals, markings, islands, and lighting. Because of the constant
increase in traffic accidents in small communities and rural sections,
there is particular merit in Wise regulation and control in these areas.
Engineering attack on automotive design also offers possibilities of
accident reduction. The great number of accidents resulting from
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winter driving hazards points up the problems of skidding and visi-
bility. These are as challenging to the automotive engineer as to the
highway engineer.
Greater safety on the highway may be attained through engineering
methods, but this will require more attention to the accident problem,
not only by engineers but by administrators and public officials as
well. There has been a general lack of appreciation of the extent to
which accidents can be reduced by application of engineering principles
and techniques.
Opportunity to Improve Engineering Contributions to Safety
It is not enough to say that greater attention must be given to en-
gineering for safety. All designs of roads and vehicles and all oper-
ational plans must be subjected to appraisal of the safety factors, both
physical and economic. But who is to do it?
Much engineering knowledge is available in this area of highway
engineering, but it has not yet had the extensive application so vitally
needed. The reason is natural enough. Legislative and highway-
administrative officials are under tremendous public pressure to pro-
duce a large mileage of highway improvements. This makes for a
continuing conflict with the engineer as he strives to employ the more
modern standards of design and work toward safer operating
conditions.
Added emphasis on the application of safety fundamentals is needed
at other places too. In education, and properly so, undergraduate
curriculums are heavily laden with the fundamentals of engineer-
ing science and allow little or no room for specialized courses in
safety. In existing courses in highway design, construction, and oper-
ation, however, there is excellent opportunity to stress the importance
and basic principles of safety.
If highway traflic safety is to attain maximum benefits from engi-
neering measures, engineers must be trained for traffic and safety work,
given experience through well-organized in—service activities, and
placed in responsible positions at key points in highway organizations
with reasonable assurance that they may find professional opportunity,
compensation commensurate with their ability and experience, and
continuity in the tenure of their positions.
Safety cannot be achieved however, as an end in itself. Rather it is
the byproduct of correct action. In the final analysis, it is the well-
organized State or local highway department, with sound engineering
and administrative methods, that will make a significant contribution
to highway safety. The department should be a balanced organiza-
tion, with adequate staff and authority to perform its official func-
tions and with every branch conscious that proper performance of its
normal duties is the best possible way to contribute to highway safety.
5
A pressing need at this time is for a greatly increased number of
well-trained, experienced traffic engineers and for a closer liaison
among design, construction, maintenance, and traffic divisions. The
training of specialists in traffic engineering requires time, but can be
expedited by the establishment at engineering colleges of graduate
fellowships in traffic and safety engineering. This, of course, will
involve increased availability of funds for this training.
Parallel with the need for more traffic engineers is the urgency for
stronger accident-record information, both in amount and quality.
Most accident reporting has been aimed at control of the individual
driver. An equally important objective, however, should be the ex-
posure of deficiencies in highway or vehicular design, or characteristics
of traffic flow that are likely to cause accidents.
In every jurisdiction—city and State—existing accident report
forms should, therefore, be reviewed by engineering agencies respon-
sible forroads and streets, to see whether they are suitable for the ac-
complishment of this second purpose. If not, they should be revised.
Specifically, the places where rural accidents occur need to be more
exactly reported. Control sections into which most highway systems .
have been divided, and the roadside-station marker posts employed
in some States, afford good identification for spotting accident sites
more precisely.
There can be no doubt that an improved accident-report form pro-
viding more pertinent data on roadway conditions, and greater volume
of better accident reporting, would be valuable aids to the engineer
in determination of design treatments.
Intensive investigation and analysis also need to be directed to the
disclosure of faults or defects in the design, material, or construction
of the vehicles involved in accidents, or of their component parts, as
Well as to highway deficiencies, and these findings called to the atten-
tion of the persons in position to effect remedies.
To spur immediate corrective action, much could be done through
intensive educational programs and through conferences for en—
gineers. These might be arranged through cooperation among gov-
ernmental authorities in charge of road and street work and other
highway groups, vehicle manufacturers, educational institutions, and
agencies concerned with safety.
A noteworthy example of great potentialities is the program adopted
by the Institute of Transportation and Traffic Engineering estab-
lished at the University of California by the State Legislature. This
program is recommended for consideration by other States and uni-
versities. It is a practical illustration of how to provide needed
training for engineers; how to get important highway investigations,
analyses, and researches undertaken; how to arrange valuable con-
ferences and cooperative enterprises between governmental agencies
6
and other qualified organizations; and how otherwise to improve en-
gineering contributions to safety.
Value of Research
Up to this point emphasis in this report has been on action through
application of proved techniques and procedures. From the long-
range viewpoint equal emphasis is warranted on the need for basic
research in the highway and automotive fields. A pay—off in safety
comes from constant alertness to the possibilities of applying the prin-
ciples discovered in basic research to design and practice. The de-
velopment of the modern all-steel vehicle body ably demonstrates the
value of research in the automotive field. The safety afforded by
the present-day vehicle body has been provided only as a result of
continued research. The steel body is an example of secondary results
derived from research and development in one field that become pri-
mary benefits in the field of highway safety. ,
Another illustration is the lowered cost of grading in highway con-
struction that resulted from research. This lowered cost makes pos-
sible the building of roads with better line and grade and more ade—
quate sight distance, thus greatly promoting highway safety.
There are many areas of engineering for safety in which informa-
tion is nowhere near complete and in which the search for new
knowledge should be greatly intensified. Of cardinal importance, for
example, is the study of driver behavior and characteristics in relation
to engineering problems. Yet in this area of research the surface has
scarcely been scratched.
The relating of highway factors to accidents has only recently begun
to receive the attention it deserves, and indications are that future
research will prove highly productive.
Much more needs to be learned about practical capacities of roads
and streets under various conditions. The forthcoming report of
the highway capacity committee of the Highway Research Board
will fill a pressing need in the field of safety.
The need for improvement in methods of lighting the highway from
moving vehicles with safety to all, is generally acknowledged. Note-
worthy of increased attention to the need and value of research is the
setting up by the Conference of an advisory group on highway safety
research.
Agencies that can conduct researches to fill in the gaps in our
knowledge are urged to do so, for only through application of re-
search findings can many of the fundamental causes of accidents be
effectively dealt with. Interested groups should contact the Highway
Research Board. Through its Research Correlation Service for the
American Association of State Highway Officials, it is in position
to be of practical service.
E fleet of Legal and Regulatory Provisions
Legislatures and regulatory bodies have promulgated many re-
quirements concerning sizes and weights of commercial vehicles and
their design, construction, and accessory equipment. Frequently
these requirements have been impractical and compliance has, there-
fore, been difficult or impossible. In some instances, the design of
vehicles has been adversely affected and the principal intent of the
law or regulation has not been realized. The result has been, prob-
ably by inadvertence, to make these vehicles less safe for operation or
to cause some adverse design changes.
It is strongly urged that legislative or regulatory bodies obtain
competent and impartial engineering advice when undertaking the
establishment of provisions affecting the design and construction of
motor vehicles or their appurtenances. Engineering counsel would
determine whether the language of the proposed regulation would ac-
complish the purpose intended and insure against new evils.
Other statutory encumbrances, the outgrowth of legislation adopted
before the development of present patterns of motor—vehicle use, have
created difficulties in the acquisition of right—of—way for modern
facilities. Legislatures need to adopt and courts to approve provisions
for control of access to high-traflic—volume routes. Similar impedi-
ments prevent the acquisition of suflicient right—of-way width or area
at intersections. These right-of-Way inadequacies contribute to an
accident rate that is higher than average on recently improved high-
ways. Legislative action is urgently needed in many places to open
the way for fully modernized routes.
Assuring Continuity of H igh-Grade Highway-Transportation
Engineering
A major challenge to highway transportation must now be met.
Sound business principles demand that the expenditure of billions for
highways be under the direction of qualified engineers. Many of the
present highway engineering leaders are close to retirement age. As
trusted lieutenants take their places and others move up to higher
positions, there must be assured a continuing influx of intelligent young
engineering graduates. Yet a recent survey by the American As~
sociation of State Highway Officials shows a deficiency of some 9,000
engineers in State highway departments alone, and reveals a la-
mentable lack of interest among current civil—engineering students in
pursuing a highway career.
Lack of proper engineering personnel in county, city and other local
road agencies is notorious. Political interference with the continuity
of highway engineering management is another serious personnel
factor which often has devastating effects on highway safety. Ways
and means must be found and applied promptly to correct this serious
and potentially disastrous situation.
8
THE HIGHWAY
Engineers have developed certain principles in highway design, con-
struction, and maintenance that, with proper application, unquestion-
ably enhance highway safety. Research and experience are constantly
adding to, and refining, these principles. In the interest of safety
these principles should be observed to the fullest extent that available
means will permit in future design and construction of all highways,
and in maintenance and reconstruction efforts.
The highway probably cannot be expected to be entirely accident-
free, of course. Regardless of its adequacy a certain proportion of
vehicles and their drivers will always be found at fault.
The highways of the United States have been built under sustained
pressure to provide a large mileage of improvement for rapidly ex-
panding motor-vehicle usage. They are an example of excellent en—
gineering to provide the most for the least expenditure—«the conse—
quence of insuflicient funds and fixed mileage goals administratively
determined.
But this approach resulted in an extensive highway network built
to 10W standards. Additional funds are therefore needed to convert
many miles of our highways to an adequate safe design.
Considerable time will be required to reconstruct those parts of
our highway mileage that have been rendered prematurely obsolete,
and to a degree unsafe, by the rapidly increasing numbers of faster and
heavier vehicles._ And while rebuilding to modern standards is in
progress, traffic will certainly continue to increase. Practicable means
must therefore be employed to reduce the dangers of the obsolete
mileage. These means include operational controls and guides, and
modest physical alterations. Principal measures of these types are
enumerated in the following section, The Operation.
Safety in travel is obviously dependent upon intimate coordination
of the features discussed separately in this section on the highway
and in the operation section. Urgent problems in both categories need
rapid solution, particularly on highways in rural areas and on their
extensions into and through small communities. On these highways
'built to low or inadequate standards, the coordination of both lines
of approach is especially important in safety achievement.
Long-Range Planning Means Safer Highways
A great lesson of the past in American highway development is
that reads and streets built only for today’s traffic needs, and not for to-
9
morrow’s, too often become congested and accident-ridden long before
their physical life is ended. Too frequently an entirely new location
must be found in order to modernize the road. Long-range planning
of future construction and reconstruction is thus of foremost impor-
tance for safety, traffic adequacy, and permanence of investment.
Promoted in part by adequately meeting highway needs, safety
must begin in planning and planning must be based on facts. Since
a comprehensive program of highway construction will necessarily
take many years, the need for planning data will be a continuing one.
Among the major planning objectives should be the collection,
analysis, and utilization of reliable accident data as related to highway
elements. By concentrating on this phase of highway research,
knowledge regarding highway safety can be expanded more rapidly.
As new data are analyzed it can be better d