イタルダ インフォメーション

ITARDA INFORMATION
交通事故分析レポート

No.105lSpecia Serious crossing collision of slow-moving
featurefour-wheeled vehicles

with two-wheeled vehicles~ Four-wheeled vehicles must exercise caution
when making right turn at non-signalized intersections~
Others0.1％

Accident detail:
Fatal and serious injury accidents
Type of accident: Crossing collision
Primary party: Four-wheeled vehicles

BicyclesFour-wheeled vehicles

1,954

1,895

31.7％

Danger perception speedof primary party: 20km/h or less

30.7％

MopedsMotorcycles

1,288

1,023

20.9％

16.6％

Two-wheeled vehicles(total)

2,311
37.5％

By type of secondary parties in the danger perception low-speed
range of the primary party of four-wheeled vehicles (Year 2013)

1 Introduction・
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2 Occurrence condition of serious accidents in the danger perception low-speed range
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・P3
of the primary party by type of accident vehicle to vehicle; crossing collision・
3 Characteristics of crossing collision between primary party of four-wheeled vehicles
・・・ P4
in the danger perception low-speed range and the secondary party of two-wheeled vehicles・
4 Case examples of accidents・
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5 Conclusion ・
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l
Specia Serious crossing collision of slow-moving four-wheeled vehicles with two-wheeled vehicles
feature~ Four-wheeled vehicles must exercise caution when making right turn at non-signalized intersections~

1 Introduction
Year 2013 recorded a reduction in the number of fatal accidents in Japan for thirteenth year in a row, at
4278 cases. Though the reduction in fatal accidents is apparent, but what about the current situation ofserious accidents?
Fig.1 shows the number of serious accidents (here it refers to accidents resulting in fatal and serious
injuries) by the danger perception speed (*1) of the primary parties (*2) indicating that serious accidents
are caused more often at the danger perception speed of 20km/h or less.
Let us now see what kind of serious accidents are caused in reality. Fig.2 shows the composition ratio of
the type of serious accidents by the danger perception speed (DPS) of the primary party. Apparently,“pedestrian-vehicle” accidents account for a constant 21-25% of the total accidents regardless of thechange in the DPS. Whereas in the low-speed range where the DPS is 20km/h or less, “vehicle-vehicle:
crossing collisions” are the most, accounting for 32% of the total.
Therefore, in this issue of ITARDA Information we shall analyze the “vehicle-vehicle crossing collision”
type of serious accidents that has occurred at the danger perception speed of 20km/h or less of the
primary party (hereinafter referred to as “Low DPS of primary party”*1: It refers to the speed at which any danger is perceived with respect to pedestrians or vehicles etc. To be more specific, it refers to the speed immediately before
taking actions such as pressing the brake or steering the handle to avoid the accident. All motor vehicles starting from mopeds fall under this category.
*2: Primary party refers to the one bearing maximum culpability among the parties directly involved in a traffic accident. Whereas, in case the mistake lies equallywith the concerned parties, it refers to the party that has sustained lesser injuries. The party opposite to the primary party is referred to as the secondary party.

Number of serious accidents

12,000

Accident detail:
Fatal and serious injury
accidents
n= 46,639 (Year 2013)

10,0008,000

Including 4,892 accidents(involving bicycles andpedestrians that are
unknown or not coveredin this survey

6,000
4,000
2,000

Others120km/h

120km/hor more〜100〜 100km/h
90〜 90km/h80〜 80km/h
70〜 70km/h
60〜 60km/h
50〜 50km/h
40〜 40km/h
30〜 30km/h
20〜 20km/h
1010km/h or less0

Fig.1 Number of serious accidents by the DPS of the primary party (Year 2013)
100%
90%
80%

5.5％
6.7％

16.5％

14.1％
Train

24.5％
20.0％

4.4％
6.5％

70%

5.7％
5.1％
3.1％

11.1％
3.5％

7.1％

60%

26.9％

50%
40%

31.8％

12.4％
26.8％
14.2％

8.3％
6.5％

30%
2.8％

20%
10%

24.0％

24.9％

20.6％

23.5％

40km/hor more

Total

Vehicle-alone
Vehicle-vehicle: Others
Vehicle-vehicle:
making right turn
Vehicle-vehicle:
making left turn
Vehicle to vehicle:
passing each other
Vehicle-vehicle:
passing or overtaking
Vehicle-vehicle:
crossing collision
Vehicle-vehicle:
rear-end collision
Vehicle-vehicle:
head-on collision

Accident detail:
Fatal and serious injury
accidentsn = 46,639 (Year 2013)
20km/h or less:n = 19,406
20-40km/h：
n = 13,040
40km/h or more：
n = 9,301
Others：n = 4,892

Pedestrian-vehicle

0%20km/h or less 20〜40km/h

Fig.2 Type of serious accidents by DPS of primary party (Year 2013)
ITARDA INFORMATION no.105

ITARDA INFORMATION no.105

2 Occurrence condition of "vehicle to vehicle crossing collision"
type of serious accidents in the Low DPS of the primary party
Let us first look into the characteristics of such serious accidents by the type of road users (primary andsecondary parties) and by the place of occurrence.
■By parties (primary and secondary)Fig.3 shows the relation in terms of the primary and secondary parties involved in the accident. Whereas
small and medium sized vehicles mainly constitute the primary parties, two-wheeled vehicles form the
majority of the secondary parties, with the ratio of motorcycle and mopeds at 28% and the bicycles at 24%.
■By place of occurrence
Fig.4 shows the situation by the place of occurrence such as signalized or non-signalized intersections (byroad widths), near intersections, ordinary roads and so on. Evidently, 70% of the crossing collisions at low
DPS of primary parties with the secondary party of motorcycles and bicycles have occurred at
non-signalized intersections. Furthermore, more than half of such collisions took place at smaller
intersections with road width 5.5m or less for the primary party of four-wheeled vehicles. Ordinary roads
account for around 20% of the accidents.
In the next section, let us focus on the crossing collision between the primary party of four-wheeled vehicles(hereinafter referred to as “4W primary party”) in Low DPS and the secondary party of two- wheeled vehicles(hereinafter referred to as “2W secondary party”) and find out why accidents take a serious result, who all are
involved and what sort of accidents occur and further analyze their causes.

100%

24.4％

1,400

15.5％

1,200

1,000

10.7％
90%

Others(railroad crossing etc.)

80%

39.9％

Near intersection

60%
66.1
％

50%
70.2
％

70.6
％

40%

800

30%

600
400

7.2％
200

35.4％
37.2％

28.3
％

13.0％

40.3％

Wide
(13m or more)
Medium(5.5m or more)
Narrow(less than 5.5m)

Signalizedintersection

20%

Moped

Motorcycle

Other types of motor vehicle

Medium and small sized
goods vehicle

0HGLXPDQGVPDOOVL]HGWUXFNLL and large sized vehicle(goods and passenger)

BicycleMoped
Motorcycle
Other typesof motor vehicle
Medium and small
VL]HGWUXFN
Medium and small
sized passenger vehicle
LL and large sized vehicle(goods and passenger)

Ordinary road

70%

11.8％

0

16.5％

17.5％

Road width for primary parties
Non-signalized intersection

12.6％

Secondary party

Fatal and serious accidents (Year 2013)

1,600

Accident detail:
Fatal and serious
accident
Type of accident:
Crossing collision
DPS of primary party:
20km/h or lessn= 6,160 (Year 2013)

10%
0%
Accident detail = Fatal and serious accidents
Type of accident = Crossing collision

All types

DPS of primary party
NPK

All DPS ranges

Primary party Primary party
= 4W
= 4W
Secondary
Secondary
party=2W party= bicycles

Primary andsecondary parties=all road users

n = 2,145

12,512

1,875

46,639

Primary party

Fig. 3 Relation between parties in crossing collisions
at the low DPS of primary parties (Year 2013)

Fig.4 Place of occurrence of crossing collisions
in the low DPS of primary parties (Year 2013)
ITARDA INFORMATION no.105lSpecia Serious crossing collision of slow-moving four-wheeled vehicles with two-wheeled vehicles
feature~ Four-wheeled vehicles must exercise caution when making right turn at non-signalized intersections~

3 Characteristics of crossing collision between 4W primary party
in low DPS and 2W secondary party■DPS of two-wheeled vehicle users
6XUSULVLQJO\VHULRXVDFFLGHQWVRFFXUGHVSLWHWKHORZ'36RINPKRUOHVVRIWKHSULPDU\SDUW\/HWXV
find out the reason.
$ERXWRIWKHFURVVLQJFROOLVLRQVRFFXUUHGDWWKH'36RINPKRURYHURIWKHVHFRQGDU\SDUW\which is more as compared to that of the primary party (see Fig.5). Further, the higher the DPS of thesecondary party, the higher the ratio of serious accidents becomes (see the line graph of Fig.5). In otherwords, if DPS of the secondary party is high, the accident becomes serious in nature despite the low
DPS of the primary party.

Ratio ofserious accidents

11.7％
6.2％

0.5％

0.2％

〜
70
80km/h

80km/hor more〜50
60km/h〜4050km/h〜3040km/h〜2030km/h〜1020km/h2％〜
6070km/h3.6％

Ratio of serious accidents

21.5％
16.2％

0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0

1XPEHURIVHULRXVDFFLGHQWV
Number of casualty accidents)

38.1％

10km/hor less

Number of serious accidents

900
800
700
600
500
400
300
200
100
0

Type of accident: Crossing collision'36RISULPDU\SDUW\NPKRUOHVV
Primary party: 4W
Secondary party: 2W
Number of serious accidents = 2,131(excluding 14 cases where the DPSof secondary party is unknown)
Number of casualty accidents = 16,811(excluding 38 cases where the DPSof secondary party is unknown)

DPS of secondary party (two-wheeled vehicles)
Fig.5 DPS of secondary party and the ratio of serious accidents (Year 2013)■Attribute of road users
Is there any peculiarity in the attributes (age and gender) of the 4W primary party and the 2W secondary party?
Categorizing the characteristics of the primary party on the basis of their attributes shows that men of
20-69 years and women in their 40s are more often involved in serious accidents in the form of crossing
collision with the 2W secondary party (see bar graph of Fig.6). Also, women in their 40s are more
frequently (1.27 times the average) involved in crossing collisions with two-wheeled vehicles in Low DPS(see line graph of Fig.6).
Relatively, no major characteristic is visible in the attributes (age and gender) of the secondary party
involved in crossing collision in the low DPS of the primary party (see line graph of Fig.7). However, thenumber of serious accidents involving men of age group 20-49 years is more (see bar graph of Fig.7).

200

0.25 Ave.＝
0.23
0.2

150

0.15

high

0

80 years or older
70-79 years
60-69 years
50-59 years
40-49 years
30-39 years
20-29 years
16-19 years

Primary party
occupant: men

Primary party
occupant: women

250
200
150
100
50
0

80 years or older
70-79 years
60-69 years
50-59 years
40-49 years
30-39 years
20-29 years
16-19 years

0

100

300

80 years or older
70-79 years
60-69 years
50-59 years
40-49 years
30-39 years
20-29 years
16-19 years

50

Relatively
0.1
low
0.05

350

Secondary party
occupant: men

Secondary party
occupant: women

Relatively
0.8 high
0.7 Ave.＝
0.66
0.6
0.5 Relatively
0.4
low
0.3
0.2
0.1
0

Ratio of relative number

0.3

250

Number of serious accidents

300

Ratio of relative number

0.35 Relatively

80 years or older
70-79 years
60-69 years
50-59 years
40-49 years
30-39 years
20-29 years
16-19 years

Number of serious accidents

350(Vertical axis 1: Number of serious accidents)
Number of accidents involving 4W primary party under below conditions (Total n=2,145)
7\SHRIDFFLGHQW&URVVLQJFROOLVLRQ'36RISULPDU\SDUW\NPKRUOHVV6HFRQGDU\SDUW\:(Vertical axis 1: Number of serious accidents)
Number of accidents involving 2W secondary party under below conditions (Total n=2,145)
Type of accident: Crossing FROOLVLRQ'36RISULPDU\SDUW\NPKRUOHVV3ULPDU\SDUW\:(Vertical axis 2: Relative composition ratio)
Under above conditions, ratio achieved by dividing the “number of accidents by age and genderof primary party” by the “number of crossing collision type of serious accidents by age andgender of 4W primary party” acts as the pointer for indicating the extent of the relative numberof accidents with the 2W secondary party in the Low DPS of the primary party.

(Vertical axis 2: Relative composition ratio)
Under above conditions, ratio achieved by dividing the “number of accidents by age and genderof secondary party” by the “number of crossing collision type of serious accidents by age andgender of 2W secondary party” acts as the pointer for indicating the extent of the relative numberof accidents with the 4W primary party in the Low DPS.

Fig.6 Number of accidents by attributesof primary party (Year 2013)

Fig.7 Number of accidents by attributesof secondary party (Year 2013)

ITARDA INFORMATION no.105

ITARDA INFORMATION no.105■Moving direction and type of movement of primary and secondary parties in traffic accident
Next, let us look into the relation between the moving direction of 4W primary parties and 2W secondary
parties as well as the number of serious accidents, majority of which occur at “non-signalizedintersections” and “Ordinary roads.”
In the case of ordinary roads, the ratio of slow-moving four-wheeled vehicles making a right turn(including those making right turn from outer roads) colliding with two-wheeled vehicles moving ahead
from the right side, is high (see Fig.8, cases 1A,1B). Whereas at the non-signalized intersections,straight-moving two-wheeled vehicles colliding with four-wheeled vehicles on their right or left side when
the latter is also moving straight on, is high (see Fig.8, cases 2B, 2C). Same as in cases 1A and 1B ofordinary roads, two-wheeled vehicles coming from the right side colliding with the four-wheeled vehicles
when the latter is making right turn, is most common (see Fig.8, case 2A).
Type of accident = Crossing collision Accident detail = Fatal and serious accident Primary party = 4W
'36RISULPDU\SDUW\NPK6HFRQGDU\SDUW\ : 0RWRUF\FOHV PRSHGV

Accident
summaryRoad
Ordinary roads (incl. near intersections)configuration
Case
1A
1B
1C
Major caseSecond mostThird mostcommon casecommon caseMovingdirectionand type of
movementof primaryandsecondarypartiesPrimary party: Making
right turn from outer road
Secondary party:
Going straight(on the right side ofprimary party)

Primary party:
Making right turn
Secondary party:
Crossing the road(on the right side ofprimary party)

Non-signalized intersections

Primary party:
Making right turn
Secondary party:
Going straight on(slipping past theright side of primary party) Others

2A
Major case

2B
Second mostcommon case

2C
Third mostcommon casePrimary party:
Making right turn
Secondary party:
Going straight(on the right side ofprimary party)

Primary party:
Going straight on
Secondary party:
Going straight(on the left side ofprimary party)

Primary party:
Going straight on
Secondary party:
Going straight(on the right side ofprimary party)

Others

2W

2W
4W
2W

2W

Number of
fatal andseriousaccidents

2W

4W

4W

114
26.5％

69
16.0％

51
11.9％

196
45.6％

2W

4W

4W

4W

370
24.6％

325
21.6％

321
21.3％

340

489
32.5％

1506

Fig.8 Moving direction of primary and secondary parties
at ordinary roads and intersections (Year 2013)■Main cause of accidents
Let us now analyze the main causes of such serious crossing collisions individually in 4W primary parties
and 2W secondary parties.
Human factors leading to accidents in primary parties point at the fact that, the slower the DPS, thegreater the frequency of “delay in noticing” becomes and the rate is about 90% in the low DPS of the
primary party (Fig.9). Further, the breakdown of “delay in noticing” shows that inadequacy in the safety
check of the surroundings increases with decrease in the DPS and 75% of such accidents in the low
DPS of the primary party are caused due to this reason (Fig.10). In other words, the major cause of
accidents with the other party is delay in noticing due to inadequate safety check of the surroundings by
the 4W primary party.
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%

Unknown
Operation error

89.8％

84.8％

76.5％

88.2％

Judgment error
Delayin noticing

Type of accident:
Crossing collision
20〜NPK
NPK
Total
Primary party: 4W
NPKor lessor more （n＝2,876） Secondary party: 2W（n＝593）（n＝136）（n＝2,145）
Accident detail:
Fatal and serious
DPS of primary party
accident

Fig. 9 Human factorsof primary parties (Year 2013)

100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%

22.1％
47.7％
74.7％

67.2％

Inadequate safety
check of thesurroundings
Failure to checksafety of thesurroundings
Failure to pay
attention forward(external factor)
Failure to pay
attention forward(internal factor)

Type of accident:
Crossing collision
20〜NPK
NPK
Total
Primary party: 4W
NPKor lessor more （n＝2,534） Secondary party: 2W（n＝503）（n＝104）（n＝1,927）
Accident detail:
Fatal and serious
DPS of primary party
accident

Fig. 10 Breakdown of “Delay in noticing”
of primary party (Year 2013)
ITARDA INFORMATION no.105lSpecia Serious crossing collision of slow-moving four-wheeled vehicles with two-wheeled vehicles
feature~ Four-wheeled vehicles must exercise caution when making right turn at non-signalized intersections~

In the case of secondary parties, similarly the human factor of “delay in noticing” leads to more
accidents. However the breakdown shows that “judgment error” accounts for about 42% (Fig.11)
especially in the low DPS of primary party which is four times the rate as compared to that of primary
party which is around 10 percent. Further, the breakdown of “judgment error” shows that failure toobserve the surrounding traffic movement (did not watch carefully anticipating the other party would yield
to and did not watch carefully as there was no apparent danger) accounts for the majority of the causes
at about 63% (Fig 12). This indicates that the 2W secondary party ends up falling prey to crossing
collisions because they continue riding at a high speed without sensing any danger.
In the following section, let us study the typical case example of accidents of four-wheeled vehicles
colliding with the two-wheeled vehicles coming from the right side while making a right turn at theintersection (Case 2A of Fig.8) and think of versatile preventive measures for the same.

100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%

22.1％

Unknown

17.2％
36.5％

41.9％

Operation error
Judgment error
Delayin noticing

56.5％

76.3％

80.8％
61.9％

Type of accident:
Crossing collision
Primary party: 4W
20km/h20〜
40km/hTotal
Secondary party: 2Wor lessor more （n＝2,227） Accident detail:40km/h（n＝1,639）（n＝489） （n＝99）
Fatal and serious
accident

DPS of primary party

Fig. 11 Human factors of
secondary parties (Year 2013)

ITARDA INFORMATION no.105

100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%

62.9％
42.6％

59.6％

Traffic
environment
Improperanticipation
Failure toobservesurrounding
traffic
movement

35.3％

Type of accident:
Crossing collision
Primary party: 4W
20km/h20〜
40km/hTotal
Secondary party: 2Wor lessor more （n＝812） Accident detail:40km/h（n＝687）（n＝108） （n＝17）
Fatal and serious
accident

DPS of primary party

Fig. 12 Breakdown of “Judgment error”
of secondary party (Year 2013)

ITARDA INFORMATION no.105

4 Case examples■Situation of accidents
On a weekday morning, Ms. A (40 years old, driving a medium-sized vehicle) was trying to make a rightturn at a small non-signalized T-intersection with a road width of 5.4 meters. Since the road was lined byfences of about 1.6m high on either side obstructing the view of both sides of the facing road, Ms.A
paused her vehicle before the intersection and checked the traffic condition of both side roads on the
curve mirror on her front. Since no vehicle was appearing on the mirror she slowly started making a rightturn. But unable to notice Mr.B (in his twenties, riding a motorcycle) who was coming from her right side
at a speed of 50km/h, her vehicle collided with Mr.B (Fig.13).

B (two-wheeled vehicle)

4.0m

1.0m
Stop

と
ま
れ

Stone fence
1.6m highA (Four-wheeled vehicle)
Concrete fence
1.8m high
5.4m

Fig.13 Figure showing the situation of the accident site
■Deliberations to prevent accidents
How can the aforementioned accidents be prevented? Let us consider the situation from the viewpoint ofboth the four and two-wheeled vehicles.
Let us start with the four-wheeled vehicle. In the above example, despite of checking the safety in termsof an approaching vehicle on both sides of the road on the curve mirror, it met with an accident. There wetested as to how much visible the traffic movement is to a four-wheeled vehicle, on the curve mirror.
As shown in Fig.14, colored cones were placed on the positions X1, X2 and X3, and photographs weredirectly taken from the center of intersection X0 which is similar to visual observation (photo1) and fromposition A1 at a height of 1.25m assuming the viewing position of driver occupying the four-wheeled vehicle
as appearing on the curve mirror (photo2). The two photographs were then compared. Even when seen by
naked eye, as the surface area of the color cones is inversely proportional to the square of the distance,
they will appear small and much smaller on the curve mirror. This is because the curve mirror is so
designed as to reflect as much information as possible (visual field) on the opposite side in a compressedstate. In layman’s words, an object more than 30m away will appear less than one-two hundredth of its
actual size on the curve mirror. That is, a motorcycle 30m away will appear only a few centimeters in sizeon the curve mirror. So not only is it difficult for a driver to notice the motorcycle which appears muchsmaller on the 5m distant curve mirror, but also to correctly judge its approaching speed and distance.
Curve mirror

XO

X1

X2

X3

≒2m
Stop

A1
Stop signpost

2.7m

10m
20m

5.4m

30m

Fig.14 Relative distance of photos taken at the accident site
ITARDA INFORMATION no.105lSpecia Serious crossing collision of slow-moving four-wheeled vehicles with two-wheeled vehicles
feature~ Four-wheeled vehicles must exercise caution when making right turn at non-signalized intersections~Photo 1 Photos of colored cones as seen from X0 position (from left: X1, X2 and X3)

Photo 2 Photos of colored cones as appearing on the curve mirror from A1 position(from left: X1, X2 and X3)
At intersections where the visibility is poor, although it is important to check the safety of surroundings
using a curve mirror, it is dangerous to rely too much on this information alone.
As inverted image is reflected on the curve mirror, the traffic situation may appear too confusing to beunderstood correctly. Similarly it is difficult to read the size, location and approaching speed of thetwo-wheeled vehicle appearing so small on the curve mirror. It is crucial to restrict the use of curve mirror
to check the existence of any approaching vehicle and to confirm visually, before finally deciding to start
your vehicle. The ideal way of visual confirmation is to first stop your vehicle at the stop line and checkthe presence of any approaching vehicle on the intersecting road on the curve mirror. Then slowly move
forward little by little till your vehicle enters the other road while securing the visibility on your left andright sides. This will help you to make a stable judgment and warn your presence to other vehicles at an
early stage, thus preventing a possible accident. It is also advisable to switch on your turn signal lights orhead lights in order to let other vehicles know your presence soon enough.
Coming to two-wheeled vehicles, however accustomed you are with the route you are riding, it isimportant that you are conscious about the presence of intersections, especially non-signalized ones,
entry and exit points of other vehicles and make sure on a routine basis to control your speed when you
approach such areas. Since it is much easier for a two-wheeled vehicle going straight on to notice anapproaching four-wheeled vehicle (larger size), the former could keep distance in order to prevent any
accident. Near such areas where you notice potential dangers such as vehicle or human movement, it isof vital importance to adequately control your speed beforehand. It can be dangerous especially whileriding straight on priority roads that are narrow. Two-wheeled vehicle riders could also take care atplaces where curve mirrors are placed at small intersections.

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ITARDA INFORMATION no.105

5 Conclusion
The characteristics of crossing collision between the slow-moving primary party of four-wheeledvehicle and the secondary party of two-wheeled vehicle are as follows:・ Despite the low speed of the primary parties, many of the secondary parties are driving at a highspeed which results in serious accidents.
・ Female drivers in their forties driving four-wheeled vehicles as the primary party at Low DPS accountfor relatively more crossing collisions with the secondary party, while young men riding two-wheeledvehicles as the secondary party meet with more accidents.
・ In the case of primary parties, the human factor of “delay in noticing” due to inadequate safety checkof the surroundings is more common. In the case of secondary parties, “judgment error” is a morecommon cause as compared to that of the primary parties. Further breakdown of this cause showsthat 63% of accidents are caused due to “failure to observe surrounding traffic movement” such as “didnot watch carefully anticipating the other party would yield to and "did not watch carefully as there was
no apparent danger”.
・ On ordinary and small roads with road width 5.5m or less with non-signalized intersections, crossing
collision of four-wheeled vehicles trying to make a right turn with two-wheeled vehicles coming straightfrom the right side, is a typical case of accident that occurs more often. (Case 1A, 1B and 2A of Fig.8of Chapter 2).
Following are the points to be careful of so as to prevent such serious accidents at the danger perception
low speed range.
Four-wheeled vehicles making a right turn (or going straight on) must…
・ visually confirm safety of the surroundings without fail: At intersections with poor visibility, although it isalright to check the presence of other vehicles on the curve mirror, but one should never rely on thisinformation alone. Slowly move forward little by little while securing the visibility and always confirm
visually one last time before you proceed.
・ make cautious decision: When making a right turn or passing through a non-signalized intersection,
proceed only when you are more confident with the timing than that of your habitual driving scene. If
you still have any doubt, do no rush and wait until you are confident enough to proceed.
・ improve conspicuity: Make use of turn signal lights or head lights to let other vehicles know yourpresence or movement easily.
Two-wheeled vehicle going straight on must…
・ enhance your danger awareness on a routine basis: Always be highly cautious while riding straight ona preference road about the presence of any non-signalized intersections and road entries or exits
ahead. Always perceive potential danger in such areas. If you notice any human or vehicle movementin these areas, reduce the vehicle speed and proceed carefully.
・ improve conspicuity: Make use of the head light to let other vehicles know your presence (or speed)
easily, even during daytime.
（Takashi Takemoto）

当センターは、平成４年（１９９２年）に国家公安委員会、運輸省（当時）、建設省（当時）から設立許可を受けて、公益法人として設立されました。
その後平成２４年（２０１２年）
４月に公益財団法人に移行しました。我が国で唯一
道 路 交 通 法の定める「 交 通 事 故 調 査 分 析 センター 」の 指 定を国 家 公 安 委 員 会 から受けた 調 査 研 究 機 関であり、 交通事故の防止と被害の軽減のための 交 通 事 故の調 査 分 析を行っています。

公益財団法人 交通事故総合分析センター
お問合せ先●ウェブサイト http://www.itarda.or.jp/●Eメール koho@itarda.or.jp

つくば 交通事故調査事務所〒101-0064
東京都千代田区猿楽町2-7-8 住友水道橋ビル8階
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ITARDA INFORMATION no.105