Systematic Processof Road Safety Countermeasures0Systematic Processof Road Safety Countermeasures
1.Process of traffic safety countermeasures
2.Collection of basic data
3.Analysis of accident factors
・Planning of countermeasures
4.Implementation of countermeasures
5.Evaluation of countermeasures

1Systematic Processof Road Safety Countermeasures
1.Process of traffic safety countermeasures
2.Collection of basic data
3.Analysis of accident factors
・Planning of countermeasures
4.Implementation of countermeasures
5.Evaluation of countermeasures21. Process of traffic safety countermeasures
Flow of planning and evaluation countermeasures shown in the Manual31. Process of traffic safety countermeasures
Traffic Safety Measures and Evaluation Manual• Systematically organizing the procedures and points to keep in mind for the planning and evaluation of traffic
safety countermeasures.
• Organizing the data necessary for planning countermeasures, examination, collection method of data, and points
to keep in mind for examination.

Procedure of traffic safety countermeasures shown in the manual
Part.1 Traffic Safety Measures andEvaluation Manual

Part.2 Guideline for Improving Road Safety
at Hazardous Spots

Chapter.1 Introduction

Chapter.1

Chapter.2 Procedure of countermeasures Chapter.2

Summary of this example
Usage of this example

Chapter.3 Drafting of countermeasures

Document.1 List of the accident factor

Chapter.4 List of countermeasures

Document.2 List of countermeasures

Chapter.5 Accumulation to accident
countermeasures database

Document.3 Example of countermeasures“Traffic Safety Measures and Evaluation
Manual”
and“Guideline for Improving Road Safety at
Hazardous Spots”

4Systematic Processof Road Safety Countermeasures
1.Process of traffic safety countermeasures
2.Collection of basic data
3.Analysis of accident factors・Planning of countermeasures
4.Implementation of countermeasures
5.Evaluation of countermeasures52. Collection of basic data

Collection and management of accident data

Local Police Station
Local Police Headquarters
investigation

call

daily fatalities reportmonthly accidents report

National Police Agency

ITARDA※1

every 3 months

quick estimation report

Accident

Daily fatalities report (ITARDA web)Monthly traffic accidents statistics (NPA web)※1 Abbreviation of “Institute for Traffic Accident Research and Data Analysis “62. Collection of basic data

Contents of accident data to collect Each accident data include minimum 67 items
 Environment;
number of the people involved, date, time, weather, road surface,road environments, type of accident, etc…

 Road User information; (include passenger information)user type, driving qualification and experience, head light,
vehicle speed, traveling direction, damage part, drink driving,pedestrian’s reflector, violation, behavior, mobile phone use,navigation use, gender, age, nationality, occupation, residence,
injury level, seatbelt/CRS/helmet use, air bags, injury condition,
main injury body part, vehicle part inflicting injury, etc…

 Additional in expressway accident
road segment, structure, curve radius, cross slope, accident type,
number of involved vehicle, traffic hindrance, travel distance, etc…
7

2. Collection of basic data

Institute for Traffic Accident Research and Data Analysis (ITARDA) Non-profit foundation established in 1992
 Achievement of safe traffic society
 Activities 1.Collect and manage the traffic accident-related data
2.Independent In-depth investigation
3.Comprehensive and scientific research and analysis human factors, trafficenvironment, vehicles
4.Disseminate knowledge about traffic accidents, and ideas about traffic safety

License registration(NPA) 81mil

Traffic accident data
(NPA)

Vehicle registration(MLIT) 82mil
Traffic census(MLIT)
governmental
accident-related data

Multi-angular
Data Analysis

Safety equipment(JAMA)
Integrated
Database

Permanent disability(Automobile Insurance)

Trauma registration(JAST)

82. Collection of basic data
Integrated Traffic Accident Database

Contain All accidents on arterial road except Property Damage Onlyaccident
 Data about accident and driver/pedestrian same as Traffic
Accident Statistical Data
 Detailed spot where the accident occurs
 Traffic volume of each type of vehicle
 Road side situation
 Detailed situation about road, traffic safety facilities and so on

9

2. Collection of basic data
Integrated Traffic Accident Database102. Collection of basic data
Integrated Traffic Accident Database112. Collection of basic data
Arterial Roads: Accidents are concentrated at specific locations.
Implementation of focused road traffic environment countermeasures forhazardous spots (black spots)

Hazardous spots

LegendLess than 100 (cases/100 million vehicle-km)
Less then 200 (cases/100 million vehicle-km)
Less than 300 (cases/100 million vehicle-km)
300 or more (cases/100 million vehicle-km)

122. Collection of basic data
Collision diagram13

2. Collection of basic data
Collection of detailed information such as the road environment by field works
Example) Viewpoint of the field worka) Sight distance・ Is the prospect of the intersection secured enough?
・ Is the pedestrian crossing(pedestrian, bicycle) at the position that it is easy to look at from a driver?

b) Road surface
・ Is there not the point affecting the runs of the car such as a wheel track or an irregularity?
・ Does the drainage of the sidewalk function enough?

c) Road marking・Traffic sign・ Are the indication contents easy to understand a mark and the road surface indication?
In addition, is the setting place appropriate?
・ Do you not confuse a driver for there being too much number of the setting of the road sign?

d) Traffic behavior•Is there a big gap between the speed limit and actual speeds?

•Are vehicle lanes blocked by automobiles turning right and turning left?

•Is there road congestion ahead?

•At intersections, is there interference between automobiles or between automobiles, bicycles and pedestrians?

14Systematic Processof Road Safety Countermeasures
1.Process of traffic safety countermeasures
2.Collection of basic data
3.Analysis of accident factors
・Planning of countermeasures
4.Implementation of countermeasures
5.Evaluation of countermeasures15

3. Analysis of accident factors・Planning of countermeasures
Guideline for Improving Road Safety at Hazardous Spots

Past countermeasures studies at hazardous spot
Guideline for Road Safety Countermeasures(Guideline for Improving Road Safety at Hazardous Spots)
Road situation

Type of accident

Accident factor

Countermeasures

Effective countermeasures based on the Guideline
Road Safety Engineering and Management, JSPP 21, Jun. 25, 201516

3. Analysis of accident causes・Planning of countermeasures
Guideline for Improving Road Safety at Hazardous Spots
Step1 : Selection of roadstructure type to be studied.

Intersection – signal installed

Step3-2 : Identification of
the caused factors andselection corresponding
Measure CodeStep3-1 : Selection of Accident
Occurrence Process based onCollision Diagram

Rear-end collision

Inadequate awareness of confirming safety

2-7

67

8

Acute angle
intersection

Obtuse angle
intersection

check points

3

Feature of Intersection
Long straight section
before intersection
Large corner
cut radius
Small corner
cut radiusenvironment

2

Crest

occurrence process

1

Steep long
downhill section

Accident

Road traffic

Sharp curve before
an intersection

Accident Typealignment

Right turn collision

Step2 : Selection of the repetitive accident type– multi-lane road * 2-lanes or less45

4-7

Failure to stop

6-14

Isn’t there an obstructionthat blocked the driver’s vision?

Inadequate confirmation
Delayed confirmation

1-1

3-1

Isn’t there an object
that made drivers inattentive?

Inadequate awareness of confirming safety
Inadequate confirmation

2-7
1-1

4-7
3-1

Not seen
Misjudgment

Judged a rightturn possible
Impossible going
Impossible right turnstraight ahead

Road Safety Engineering and Management, JSPP 21, Jun. 25, 201517

3. Analysis of accident causes・Planning of countermeasures
Guideline for Improving Road Safety at Hazardous Spots
Step4-1 : Select the code designatedStep4-2 : Select measures from the list
corresponded code

Measurecode1-1

1
2

ObjectiveMeasures

Provide information of anintersection ahead
Improve road structures toprovide necessary visibility

Install a warning sign e.g.
indicating an intersection
Alignment improvement

Refer to measure samples on the listed
page

Important Notice for selecting
and implementing measures

Improve the alignment just before
the intersection

page136

Study in cases where it is possible toimplement large scale improvement
Control a traffic light so thatvehicles can stop safely137

4 Control vehicles turning right138

3

and oncoming to prevent themfrom simultaneous entering theintersection

Road Safety Engineering and Management, JSPP 21, Nov. 6, 201418

Systematic Processof Road Safety Countermeasures
1.Process of traffic safety countermeasures
2.Collection of basic data
3.Analysis of accident factors
・Planning of countermeasures
4.Implementation of countermeasures
5.Evaluation of countermeasures19

4. Implementation of countermeasures

Traffic safety projects implemented by road administratorsand public safety commissions (intersection)

Bicyclecrossing

Improving traffic signal patterns(Special light pattern for rightturns)
Pavement improvement(non-slip paving)(colored paving)

Right-turn lane

Directional line
(road marking)Roadlighting

Paving improvement(drainage paving)20

4. Implementation of countermeasures

Traffic safety projects implemented by road administratorsand public safety commissions (road section)
Urban roads

Rural mountainous roads
Road lighting
Trafficsignal

Median Strips

Trafficinformation
signRoad lighting

Warningboard
Curve sign
(Guidelight etc.)
Pedestriancrossing

Paving improvement(drainage pavement)(colored pavement)(non-slip pavement)

Roadlighting

Guardfence

Road surface indicators
Pavement improvements(non-slip paving)(bumpy paving)

Guardfence
Drainagepavement

Overtaking prohibition
Road studs21

4. Implementation of countermeasures
Efforts to prevent traffic accidents
・Measures to prevent traffic accidents at a road section

BeforeAfter“Slow down” signs on road surface

Simple median (blocks, rubber posts)

Yearly average number

・Number of accidents at the road section 追突
before and after the measures were taken
正面衝突

of accidents

9.0
8.0
平 7.0
均 6.0
件
事 5.0/故 4.0
年件 3.0
数 2.0
1.00.0（その他

Rear-end Collisions
Other）

Head-on Collisions
Before
対策前

After
対策後

**Source: Ministry of Land, Infrastructure, Transport and Tourism22

4. Implementation of countermeasures
Efforts to prevent traffic accidents
・Measures to prevent traffic accidents at an intersection

After

BeforeRoad lighting

Colored pavement

Traffic island

Pedestrian crossings
追突・Number of accidents at the intersection before and after the countermeasures were taken
Yearly average number

7.0

Daytime
昼間

7.0

6.0

Nighttime
夜間

右折時

6.0

（平 5.0
均件
事 4.0/
故 3.0
年件
2.0
数1.0

その他

5.0of accidents

左折時

Rear-end Collisions
Accidents when Turning Left

4.0）

3.0

Accidents when Turning Right

2.0

Other

1.0

0.0

0.0
BeforeAfter

BeforeAfter

対策前 対策後
対策前 対策後**Source: Ministryof Land, Infrastructure, Transportand Tourism

23

Systematic Processof Road Safety Countermeasures
1.Process of traffic safety countermeasures
2.Collection of basic data
3.Analysis of accident factors
・Planning of countermeasures
4.Implementation of countermeasures
5.Evaluation of countermeasures245. Evaluation of the countermeasures
Evaluation of the measures
1) Evaluation based on accident data•

This can directly and quantitatively clarify the effectiveness of a countermeasure.

•It takes time to accumulate accident data.

•The occurrence of traffic accidents fluctuates seasonally and from year to year.

•

It is necessary to collect at least one year of accident data (about 4 years for an appropriate
evaluation).

•It is necessary to also study accident patterns focused on countermeasure selection time in orderto evaluate the effectiveness of a countermeasure.

2) Evaluation based on traffic behavior•

This can evaluate the effectiveness of countermeasures, which cannot be clarified by trafficaccident data; reducing opportunities for mutual interference between automobiles for example.

•This can clarify whether or not countermeasure effectiveness is manifest without waiting toaccumulate traffic accident data.

3) Evaluation based on questionnaires•

This qualitatively compares change of consciousness of road users passing through the object
location after the execution of the countermeasure to evaluate the countermeasure•It can evaluate from the perspectives of road users, by improving feelings of security whilepassing through the same location after the countermeasure.

25