Parkways and park roads :: :: University of Virginia Library

LECTURE 3: SAFETY

The National Highway Safety Act of 1966 laid down eighteen
standards authored by AASHO to improve highway safety through design.
Most deal with roadside design for which we landscape architects
have special responsibility.

The fact that about a third of the traffic deaths involve
collisions with some fixed objects within thirty feet of the pavement
prompted the Insurance Institute for Highway Safety to initiate
a study in 1973 through the law firm of Arnold and Porter of
Washington, D. C. The result of that study, The Law and Roadside
Hazards, by Fitzpatrick, Sohn, Silfen and Wood, is the basis for
much of the following discussion.

Eighteen recommendations of AASHTO contained in the Yellow Book:

1.

Any feature found during plan review which is likely to cause
accidents will be eliminated from the plan; safety characteristics
will be deliberately designed into the plan.

2.

Removal of roadside hazards will be paramount in safety programs
of every state.

3.

Field investigations will be made to evaluate existing and new
designs of safety features for their effectiveness and cost.

4.

Embankment and cut slopes 6:1 or flatter will be provided for
improved vehicle recovery.

5.

Full width shoulders will be carried across all structures,
flush with adjoining lane, and so marked to discourage through traffic.

6.

Clear recovery areas will be provided at least 30 feet wide in
rural areas and programs undertaken to eliminate trees, drainage
structures, massive sign supports, utility poles; otherwise
adequate guardrails will be provided.

7.

Gore areas (exits from a freeway) will be kept clear of fixed
objects except that exit signs (permissible) will be mounted
on breakaway posts.

8.

Roadside will be reviewed continually to minimize signs and
resist additions.

9.

Necessary signs will be moved back from pavement at least
30 feet.

10.

Overhead signs will be used for increased visibility to all
traffic for lane assignments.

11.

Greater use will be made of existing overhead structures for
mounting signboards.

12.

Breakaway lighting standards and sign supports are recommended;
concrete bases will be flush with the ground surface.

13.

Consistent policy for guardrail is needed nationwide; designers
must regard guardrails as protection to the driver rather than
protection to the roadway; guardrails approaching structures
should be attached to the structure; approach ends will be flared
and secured to the ground; mounting posts in medians will be
6'3" apart; bolts will be fastened with washers to prevent their
pulling through the rail.

14.

Median 60-80 feet wide is desirable; barriers will be considered
for medians 30 feet wide or narrower.

15.

Two-span bridges are recommended over divided highways to
eliminate piers adjacent to outside shoulders.

16.

Median barriers will be used between twin bridges crossing
divided highways; median will be bridged on separations up
to 20 or 30 feet.

17.

Truck climbing lanes will be provided on long grades; escape
areas on long downgrades.

18.

Lighting will be provided at critical locations and intersections;
higher mounting heights will be used to reduce number
of standards required, to place them farther from the roadway
and to reduce glare.

The "Yellow Book" has become so widely accepted that it is
generally regarded as a standard by the States, by FHWA, and by
the courts. Surely this effort held a greater promise of achieving
nationwide uniformity than a Federally imposed standard because it
is authored by the State Highway Officials themselves and made a
part of FHWA's accepted standards.

* * * * *

A quick review of the statistics will show the need for greater
commitment by all of us to the problems of highway safety:

National Safety Council - 1972 - reported that of 56,600
fatalities, 19,000 involved roadside hazards or overturning.

FHWA - 1968-1971 - reported that 51.8% of the fatalities on
Interstates were single car runoffs; most involved fixed objects.

Pennsylvania DOT - 1972 - reported that 682 of 2085 fatalities
were related to fixed objects.

The GAO, in reviewing FHWA's 1970 report, determined the following
cost-effectiveness data:

1.

4.78 lives could be saved and 86.96 injuries avoided for each
$1 million spent on highway safety improvement work.

2.

0.77 life could be saved and 19.33 injuries avoided for each
$1 million spent on regular construction on the Interstates.

3.

1.1 lives could be saved and 38.85 injuries avoided for each
$1 million spent on safety improvement work on primary,
secondary and urban roads.

GAO's conclusion: Highway safety improvement work is about five
times greater than regular construction work in lives saved, and
three times greater in injuries avoided.

These figures indicate that the need is to improve existing
roadways rather than to spend safety finds on new construction—
but the sad fact is, according to GAO, that during the seven years
following the 1966 Act, the States had spent only 2.1% of the Federal
apportionment on safety projects.

* * * * *

In light of the statistics, let's look at the procedures under
which the States obtain Federal-Aid and the sequence of their projects
for new construction:

The State Highway Departments are required to submit a program
for FHWA approval to qualify for 50% (primary, secondary, urban
roads) or 90% (Interstate) financial aid. Following program approval,
the States proceed to:

1.

conduct public hearings on proposed location and submit a
report of the hearings including effects on air, noise, and
water quality fo FHWA for approval. (location; draft of EIS)

2.

prepare preliminary engineering programs and projects, (design)

3.

conduct public hearings on preliminary design and submit a
report to FHWA for approval. (EIS)

4.

prepare right-of-way programs and projects. (acquisition)

5.

prepare construction programs and projects and submit to
FHWA for approval (PS & E)

6.

construction according to plans and specs (inspected by FHWA)

7.

final inspection (acceptance for compliance by FHWA)

8.

maintenance (and public use)

Once PS & E approval has been granted, the Federal Government
has a contractural obligation for payment (50% to 90%). Upon completion
the State has sole responsibility for maintenance and can
initiate requests for safety improvement work in the future.

* * * * *

In 1973 an amendment to the Federal-Aid Act of 1916 permitted
the Secretary of Transportation to issue a "Certification Acceptance"
to the States on the condition that the State would perform its
responsibilities in accordance with the laws and standards "at
least equivalent" to those in Title 23. Because progress was so
slow in the initiation of program requests by the States for safety
improvements, Congress appropriated separate money (from Federal-Aid
funds) for abatement of high-accident locations and removal of roadside
obstacles:

1974 - $50 million for high-accident-abatement on Federal-Aid Roads
1975-1976 - $75 million for high-accident-abatement on Federal-Aid Roads
1974 - $25 million for removal of roadside hazards on Federal-Aid Roads
1975-1976 - $75 million for removal of roadside hazards on Federal-Aid Roads
1974 - $50 million for both programs on all roads outside F-A System
1975-1976 -$100 million for both programs on all roads outside F-A System

The Secretary of Transportation, in an effort to implement the
1966 Act, issued eighteen standards for compliance, 3½ of which are
under the FHWA to enforce; the remainder are under the National
Highway Safety Bureau.

Standard 9 - requires each State to have a program for identifying
accident locations and for maintaining surveillance of those
locations.

I.

The program shall have as a minimum:
- A procedure for identification of accident locations:
  - to identify experience and losses
  - to produce an inventory of
    - high accident locations
    - locations where accidents are increasing sharply
    - design and operating features associated with high
      accident frequencies
  - to take appropriate measures for reducing accidents
  - to evaluate effectiveness of safety improvements
- A systematically organized program
  - to maintain continuing surveillance for potentially
    high accident locations
  - to develop methods for their correction

II.

The program shall be periodically evaluated by the State;
an evaluation summary will be provided to the NHSB.

Standard 12 - requires that each State shall have a program of
highway design, construction, and maintenance to improve highway
safety.

I.

The program shall have as a minimum:
- Design standards relating to safety features for all new
  construction or reconstruction
- Safe traffic environment for pedestrians and motorists in
  subdivisions and residential areas.
- Roadway lighting provided on priority basis for:
  - urbanized areas
  - junctions of major highways in rural areas
  - locations of high night-to-day accidents
  - tunnels and long underpasses
- Standards for pavement design and skid resistance
- Program for resurfacing to improve skid resistance
- Control of traffic at construction sites and detours
- Inventory of railroad crossings and program for elimination
  of hazards
- Roadway maintenance is consistent with design standards
- Hazards within ROW are identified and corrected
- Design and construction features for accident pr vention
  and survivability for at least:
  - roadside clear of obstacles
  - 2. breakaway supports for control devices and lighting
  - protective devices wherever fixed objects can not be
    removed
  - bridge railings and parapets designed to retain vehicles
    and minimize danger to traffic below
  - guardrails to protect people from out-of-control vehicles
    at playgrounds, schools, commercial areas
- post crash program which includes at least:
  - signs directing motorists to hospitals
  - personnel trained in summoning aid, protection at
    accident sites, removing debris
  - access and egress for emergency vehicles on freeways

II.

The program shall be periodically evaluated by the State for
effectiveness in reduction of accidents; an evaluation summary
will be provided to NHSB.

Standards 13 and 14 - relate to traffic engineering and pedestrian
control; the other standards are administered by the NHSB:

1. Vehicle inspection
2. Vehicle registration
3. Motorcycle safety
4. Driver education
5. Driver licensing
6. Codes and laws
7. Traffic courts

8. Alcohol and safety
10. Traffic records
11. Medical emergency
15. Police services
16. Debris and clean-up
17. School buses
18. Investigation and reports

Subsequent instructional memoranda were issued by the Federal
Highway Administrator which specified that high speed design highways
would be those where design speed is 50 MPH or more with ADT of 750
or more. Those design standards contained in the "Yellow Book" are
accepted by the FHWA as supplements. (A separate list of AASHO
standards and specifications will be furnished to you during the
course for future reference.)

From time to time, FHWA issues additional standards which result
from observation of conditions or programs of research and testing:

culverts and bridges over streams, for instance, are to be designed
for 50-year frequency or the greatest flood of record with run-off
based on expected development on the watershed over the next 20 years;
inlets and pavement drainage are to be spaced so that nor more than
½ of a through traffic lane is flooded during a 10-year frequency
storm, except that a 50-year frequency is used at depressed sections.

Experiments have been conducted for the use of crash cushions
to absorb the impact of vehicles upon fixed objects. Three devices
are currently acceptable and testing of other devices is continuing.
Test criteria used by FHWA follows:

Vehicle weight range	2000-4500 pounds
Vehicle speed	60 MPH
Impact Angle	0°-25° measured from roadway
Average permissible deceleration	12 g's maximum, preventing impact with object

Minimum dimensions for a crash cushion are 6′x 8′ at 30 MPH,
6′x 17′ at 50 MPH, 6′x 28′ at 70 MPH, and 6′x 35′ at 80 MPH; the
preferred length and width of crash cushions are twice that size!

Summary:

Apart from the Laws regarding pendent jurisdiction, negligence,
sovereign immunity, liability, etc. which are too complex for me to
understand, are the responsibilities laid down by the ASLA and the
design standards laid down by FHWA as minimum measures of the designer's
performance. We must accept the duty to design in the expectation
that accidents will occur and that the recovery zone adjacent
to the highway must be safe for vehicles leaving the paved sections.

Designers have been brought to court (will be in the future) for
injuries suffered by motorists simply because our work effects the
public health and safety. The accident rate on our highways can be
improved by the judgment and competence of the designer. Our judgments
may be rejected for sound reasons, but we are obligated,
nonetheless, to present the safest design within the state of the
art and to raise our own level of competence constantly.

University of Virginia Library

LECTURE 3: SAFETY

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