(Akio Takahashi)

イタルダインフォメーションに関するお問い合せ先

渉外事業課

TEL 03-5577-3973

FAX 03-5577-3980

公益財団法人 交通事故総合分析センター●ウェブサイト http://www.itarda.or.jp/ ●Eメール koho@itarda.or.jp●フェイスブック http:facebook.com/itarda.or〒101-0064 東京都千代田区猿楽町2-7-8 住友水道橋ビル8階
TEL 03-5577-3977(代表) FAX 03-5577-3980

ITARDA INFORMATION no.114

つくば 交通事故調査事務所

67％

60%

2014
2,325 accidents

50%

40%

30%

20%

19％
7％

10%

3％

3％

P

he
Ot

res ians
l
o
c
s
r
y
ot e
st
M cycl Bic ede

r

0

s

11

70%

le

27

住 友 水 道 橋 ビル８ 階

The first thing I remember learning in the skills training at driving school was: “When exiting the vehicle, you must
check to see whether or not there are any vehicles approaching from behind before opening your door.” Now that
I once again recall this matter from back when I first began learning how to drive, I would like to go back to basics
and tie this in with promoting safer driving.
Incidentally, driving schools in the Netherlands teach students to open doors by twisting their body to use thehand on the opposite side of their body away from the door to open it. By instilling this habit in them, it makes it
so that drivers can naturally check to see if there are any bicycles or the like behind them.

~ Stopped vehicles can pose a danger ~ic

Postscript

Dooring accidents by parked
or stopped vehiclesvehBicyclists / motorcyclists should also make efforts to ensure that they do not end up as victims.
・ They should refrain from passing between vehicles stuck in traffic to the extent possible, while also
reducing their speed appropriately.
・ When passing beside four-wheeled vehicles, they should leave enough space between them.
・ They should pay attention to what the people inside of four-wheeled vehicles are doing while thevehicle is parked or stopped.

lSpeciafeatureMotorcycles and bicycles
No.114tend to overwhelmingly
be at risk of encountering
a dooring accident!
公益財団法人 交通事故総合分析センター〒101 0064 東 京 都 千 代 田 区 猿 楽 町 ２ ７ ８

Based on the analysis results of the human factors, to start with it will be necessary to get drivers of four-wheeledvehicles to soundly check for safety.
・ When opening doors, drivers should get in the habit of opening them after first checking to make sure it is safe
to do so around them.
・ In order to expand their range of visibility, drivers should proactively make use of their rear-view mirror andside-view mirrors.
・ When opening doors, they should start by opening them a little, then opening them slowly, rather than throwing
them open all at once.
・ When drivers have passengers riding with them, they should encourage their passengers to pay attention byconfirming their surroundings in advance, while getting on and off.
・ They should be attentive to pedestrians and baby strollers and the like passing beside their vehicle,
even in parking lots.

交通事故分析レポート No.114

4W■To decrease accidents

ITARDA INFORMATION

Rate for the no. of accidents

・ Bicycles account for the majority of the counterparts to dooring accidents at two-thirds of the total, followed
next by motorcycles at 20%.
・ When it comes to collisions with four-wheeled vehicles, most of these were collisions from the rear. As for thecollision rates with the left and right doors, with bicycles the rate was equivalent for both sides while formotorcycles the rate for the left door was four-times greater than that for the right door.
・ The collision speed for motorcycles is 30km/h or slower in most cases, of which more than half of the cases
were between 10km/h and 20km/h.
・ In most cases the degree of personal injury amounted to slight injuries, with the points of injury concentrated
mainly in arms and legs. However, cases where people were injured in the neck and higher accounted for
one-fourth of the total.
・ The trip purposes for four-wheeled vehicles mainly consisted of work in most cases, whereas for bicycles /motorcycles this often included commuting to work, shopping, and visiting / picking up.
・ For men driving four-wheeled vehicles, the accident rate increases as they get older, whereas for men on
bicycles / motorcycles it peaks in their 30s and then declines thereafter as they get older. For women driving
four-wheeled vehicles this peaks in their 40s, then gradually decreases before and after this, while for womenon bicycles / motorcycles this increases slightly from their 20s through their 40s, before starting to decline
again after this.
・ Human factors for four-wheeled vehicles are mostly due to failure to confirm safety factors. With bicycles /motorcycles there are no human factors in more than half of the cases, followed by failure to observe
surrounding traffic movement, failure to confirm safety factors, and failure of prediction.

ITARDA INFORMATION■Characteristics of the analysis results

交通事故分析レポート

4 Conclusion

イタルダ インフォメーション

Rate for the no. of accidents from being dooredby a four-wheeled vehicle by type of party (2014)

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l
SpeciafeatureDooring accidents by parked or stopped vehicles~ Stopped vehicles can pose a danger ~ITARDA INFORMATION no.114

1 Introduction

3 Analysis of the characteristics of dooring accidents

The presumption with cars is that they are driven as vehicles for conveying people around, and as a result
various different traffic accidents occur. But when the question is posed regarding whether stopped cars aresafe, this cannot necessarily be said to be the case. In some cases stopped cars can also cause traffic
accidents. Have you ever had the experience when you are trying to slip past beside a stopped car and adoor suddenly opens and startles you, or actually hits you?
“While a car was stuck in traffic, a door suddenly opened and someone got out of the passenger seat.” “Ithought the taxi had stopped, but then suddenly the door flew open so that the passengers could get in.”
“When I tried to go passed a car parked along a shopping street while evading it, the driver’s side door
suddenly flew open.” These include some cases that occurred in places other than roads, such as thefollowing: “As I was walking between cars in the parking lot of a supermarket a door suddenly flew open.”
As these indicate, even when cars are not driving around they can potentially pose a danger while stopped
depending on the time and circumstances, such as from doors suddenly opening. Motorcycles and bicycles,
which have many opportunities to pass by on the left side of cars while they are stuck in traffic or otherwise
stopped, must pay particular attention. What is more, in many cases young children and the like are unable toadequately predict this sort of danger, and so even greater caution is required for them. These same points
hold true for those driving and riding in four-wheeled vehicles. Motorists and passengers must constantly beaware of the fact that carelessly opening doors can lead to accidents.
Therefore, in this issue we will clarify the actual accident conditions and causes for accidents caused by
opening the doors of four-wheeled vehicles by focusing on the problem from the standpoint of both theperpetrators and the victims. In addition, we will also consider countermeasures* to prevent such accidents
from occurring.

■Counterparties to dooring accidents
What sorts of counterparties tend to encounter
dooring accidents?
Fig. 3 shows the rate for the number of accidents bytype of party from dooring accidents by four-wheeledvehicles in 2014. The total number of accidents is
2,325, of which the rate accounted for by bicycles is
the highest at 67%, followed next by motorcycles at
19%, with the two of these accounting for nearly
90% in actuality.
Vehicles like bicycles and motorcycles are highly
maneuverable which, when coupled with the factthat they have many opportunities to pass rightbeside four-wheeled vehicles that are stopped intraffic and the like, is believed to produce theseresults. Moreover, the fact that there are few
four-wheeled vehicles is because sufficient space
between parked or stopped vehicles is secured for
passing through, and so these are often limited tojust property damage. So conceivably these are notbeing counted in the number of accidents.
In light of this, for our purposes here we would liketo define the counterparties to dooring accidents
primarily as bicycles and motorcycles in moving
forward with our analysis.

* Countermeasures generally include two aspects: hard and soft aspects, and this paper will deal with soft aspects from the standpoint of what drivers can deal within their immediate surroundings.

2 Cases of accidents while parked or stopped
The following two cases are accidents that actually happened. This shows that dooring accidents occur not
only on roadways, but also in parking lots. Fortunately, these cases did not result in the deaths of Mrs. B or
Mr. D, but they were just one misstep away from danger that could have resulted in severe accidents. With
the case on the left, if an oncoming car had been coming, Mrs. B may not have been so lucky. With the caseon the right, if the site of the impact had been worse, it could have resulted in a serious situation.

AC

4W vehicles

Other

3％

3％

Pedestrians

7％

Motorcycles

19％

2014
2,325
accidents
Bicycles67％

Fig. 3. Rate for the no. of accidents
from being doored by a four-wheeled vehicle
by type of party (2014)■Counterparties to dooring accidents
When it comes to dooring accidents, which direction do bicycles and motorcycles approach four-wheeledvehicles from and with which door—right or left—do they have a higher rate of collisions?
Fig. 4 shows the number of accidents by the direction of movement of the bicycle or motorcycle and the pointof collision with the four-wheeled vehicle in 2014. First off, for the direction of movement, the majority of thecollisions occur from behind the four-wheeled vehicle. Next, looking at the collision rates for bicycles andmotorcycles against the right / left doors reveals that bicycles have collision rates that are roughly equivalent
between the right and left doors. In contrast with this, motorcycles have a collision rate with left doors that isfour-times greater than that for right doors. When motorcycles pass by on the left side of four-wheeledvehicles that are waiting at traffic signals or stuck in traffic, they are forced to ride close to the left side offour-wheeled vehicles without being able to ride on the sidewalk to avoid roadways the way that bicycles can.
As a result, this is believed to be why they have a higher rate of collisions with left door.
1200
BicyclesMotorbike
Speed: 30km/h

DBicycleSpeed: 10km/h

Fig. 1. Example of a dooring accident (on a roadway)

Fig. 2. Example of a dooring accident (parking lot)In the early afternoon of a weekday, Mrs. A (40s, female,passenger car) parked her car on the left side of the roadto go to a post office on the right side. When exiting thevehicle, she was in a rush and so she failed to check her
surroundings to see if it was safe before opening her door
without thinking. Doing so caused a collision with Mrs. B(60s, female, motorbike) who was driving at a speed ofapproximately 30km/h from behind her and to the right.
Mrs. B’s vehicle was overturned and she was thrown into
the oncoming lane (she was seriously injured, and took
50 days to make a full recovery).

On a weekday morning, Mr. C (50s, male, light cargovehicle) went to a supermarket to go grocery shopping
and parked his vehicle in the parking lot. As he was
exiting the vehicle, he opened the driver’s side door
without checking to see if it was safe behind him and to
the right. As a result, the door hit Mr. D (80s, male,bicycle), who had been traveling in a straight line fromthat direction at a speed of about 10km/h, on his left side,and Mr. D was knocked over to the right from the force(slight injuries from bruising to his head).

ITARDA INFORMATION no.114

1000

No. of accidents

B

16％

800

Motorcycles

4-times
4％

600

50％

400

40％

Equivalent
34％

36％

200
0

Left
door

Right
door

Other

Collisions from infront of the 4W vehicle

Left
door

Right
door

Other

Collisions frombehind the 4W vehicle

Left
door

Right
door

Other

Collisions fromanother direction

Direction of movement of bicycles and motorcycles and the point of collision with 4W vehicles

Fig. 4. No. of accidents by the direction of movement of bicycles andmotorcycles and the point of collision with four-wheeled vehicles (2014)
ITARDA INFORMATION no.114

lSpeciafeatureDooring accidents by parked or stopped vehicles~ Stopped vehicles can pose a danger ~ITARDA INFORMATION no.114

1 Introduction

3 Analysis of the characteristics of dooring accidents

The presumption with cars is that they are driven as vehicles for conveying people around, and as a result
various different traffic accidents occur. But when the question is posed regarding whether stopped cars aresafe, this cannot necessarily be said to be the case. In some cases stopped cars can also cause traffic
accidents. Have you ever had the experience when you are trying to slip past beside a stopped car and adoor suddenly opens and startles you, or actually hits you?
“While a car was stuck in traffic, a door suddenly opened and someone got out of the passenger seat.” “Ithought the taxi had stopped, but then suddenly the door flew open so that the passengers could get in.”
“When I tried to go passed a car parked along a shopping street while evading it, the driver’s side door
suddenly flew open.” These include some cases that occurred in places other than roads, such as thefollowing: “As I was walking between cars in the parking lot of a supermarket a door suddenly flew open.”
As these indicate, even when cars are not driving around they can potentially pose a danger while stopped
depending on the time and circumstances, such as from doors suddenly opening. Motorcycles and bicycles,
which have many opportunities to pass by on the left side of cars while they are stuck in traffic or otherwise
stopped, must pay particular attention. What is more, in many cases young children and the like are unable toadequately predict this sort of danger, and so even greater caution is required for them. These same points
hold true for those driving and riding in four-wheeled vehicles. Motorists and passengers must constantly beaware of the fact that carelessly opening doors can lead to accidents.
Therefore, in this issue we will clarify the actual accident conditions and causes for accidents caused by
opening the doors of four-wheeled vehicles by focusing on the problem from the standpoint of both theperpetrators and the victims. In addition, we will also consider countermeasures* to prevent such accidents
from occurring.

■Counterparties to dooring accidents
What sorts of counterparties tend to encounter
dooring accidents?
Fig. 3 shows the rate for the number of accidents bytype of party from dooring accidents by four-wheeledvehicles in 2014. The total number of accidents is
2,325, of which the rate accounted for by bicycles is
the highest at 67%, followed next by motorcycles at
19%, with the two of these accounting for nearly
90% in actuality.
Vehicles like bicycles and motorcycles are highly
maneuverable which, when coupled with the factthat they have many opportunities to pass rightbeside four-wheeled vehicles that are stopped intraffic and the like, is believed to produce theseresults. Moreover, the fact that there are few
four-wheeled vehicles is because sufficient space
between parked or stopped vehicles is secured for
passing through, and so these are often limited tojust property damage. So conceivably these are notbeing counted in the number of accidents.
In light of this, for our purposes here we would liketo define the counterparties to dooring accidents
primarily as bicycles and motorcycles in moving
forward with our analysis.

* Countermeasures generally include two aspects: hard and soft aspects, and this paper will deal with soft aspects from the standpoint of what drivers can deal within their immediate surroundings.

2 Cases of accidents while parked or stopped
The following two cases are accidents that actually happened. This shows that dooring accidents occur not
only on roadways, but also in parking lots. Fortunately, these cases did not result in the deaths of Mrs. B or
Mr. D, but they were just one misstep away from danger that could have resulted in severe accidents. With
the case on the left, if an oncoming car had been coming, Mrs. B may not have been so lucky. With the caseon the right, if the site of the impact had been worse, it could have resulted in a serious situation.

AC

4W vehicles

Other

3％

3％

Pedestrians

7％

Motorcycles

19％

2014
2,325
accidents
Bicycles67％

Fig. 3. Rate for the no. of accidents
from being doored by a four-wheeled vehicle
by type of party (2014)■Direction of movement and point of collision
When it comes to dooring accidents, which direction do bicycles and motorcycles approach four-wheeledvehicles from and with which door—right or left—do they have a higher rate of collisions?
Fig. 4 shows the number of accidents by the direction of movement of the bicycle or motorcycle and the pointof collision with the four-wheeled vehicle in 2014. First off, for the direction of movement, the majority of thecollisions occur from behind the four-wheeled vehicle. Next, looking at the collision rates for bicycles andmotorcycles against the right / left doors reveals that bicycles have collision rates that are roughly equivalent
between the right and left doors. In contrast with this, motorcycles have a collision rate with left doors that isfour-times greater than that for right doors. When motorcycles pass by on the left side of four-wheeledvehicles that are waiting at traffic signals or stuck in traffic, they are forced to ride close to the left side offour-wheeled vehicles without being able to ride on the sidewalk to avoid roadways the way that bicycles can.
As a result, this is believed to be why they have a higher rate of collisions with left door.
1200
Motorcycles

Motorbike
Speed: 30km/h

DBicycleSpeed: 10km/h

Fig. 1. Example of a dooring accident (on a roadway)

Fig. 2. Example of a dooring accident (parking lot)In the early afternoon of a weekday, Mrs. A (40s, female,passenger car) parked her car on the left side of the roadto go to a post office on the right side. When exiting thevehicle, she was in a rush and so she failed to check her
surroundings to see if it was safe before opening her door
without thinking. Doing so caused a collision with Mrs. B(60s, female, motorbike) who was driving at a speed ofapproximately 30km/h from behind her and to the right.
Mrs. B’s vehicle was overturned and she was thrown into
the oncoming lane (she was seriously injured, and took
50 days to make a full recovery).

On a weekday morning, Mr. C (50s, male, light cargovehicle) went to a supermarket to go grocery shopping
and parked his vehicle in the parking lot. As he was
exiting the vehicle, he opened the driver’s side door
without checking to see if it was safe behind him and to
the right. As a result, the door hit Mr. D (80s, male,bicycle), who had been traveling in a straight line fromthat direction at a speed of about 10km/h, on his left side,and Mr. D was knocked over to the right from the force(slight injuries from bruising to his head).

ITARDA INFORMATION no.114

1000

No. of accidents

B

16％

800

Bicycles

4-times
4％

600

50％

400

40％

Equivalent
34％

36％

200
0

Left
door

Right
door

Other

Collisions from infront of the 4W vehicle

Left
door

Right
door

Other

Collisions frombehind the 4W vehicle

Left
door

Right
door

Other

Collisions fromanother direction

Direction of movement of bicycles and motorcycles and the point of collision with 4W vehicles

Fig. 4. No. of accidents by the direction of movement of bicycles andmotorcycles and the point of collision with four-wheeled vehicles (2014)
ITARDA INFORMATION no.114

Dooring accidents by parked or stopped vehicles~ Stopped vehicles can pose a danger ~ITARDA INFORMATION no.114

100％

98％

4W vehicles

80％

Motorcycles

96％

60％

62％

Motorcycles
Bicycles

38％

40％

30％

24％

25％
20％

8％

10％

11％
6％

5％

5％

Chest Stomach Back

Hips

53％
0％

40％

25％

18％

20％

All
Head
injuries

Face

Neck

Arms

Legs

Major points of personal injury

SuﬀoNo-cation / injury
drowning, etc.

Noncounterparty

Fig. 7. Rate for the no. of accidents by major point of personal injury (2014)
0％

While
stopped

〜10

〜20

〜30

〜40

〜50

Over 50 Unable toascertain

Danger perception speed (km/h)
Fig. 5. Rate for the no. of accidents by danger perception speed (2014)■Degree of personal injury and major points of personal injury
To what degree are people injured by dooring accidents?
Fig. 6 shows the rate for the number of accidents by degree of personal injury in 2014. Fortunately, mostdooring accidents only resulted in slight injuries, but some cases of severe injuries were also seen. There
were no such accidents in 2014 that resulted in fatalities, but over the past ten years between about zero andfour such accidents have occurred each year.
Fig. 7 shows the rate for the number of accidents by major points of personal injury in 2014. It reveals thatmost of the injuries were slight injuries in degree, and were concentrated mainly among rider’s arms and legs.
Furthermore, the rate of injuries to areas above the neck came to one-fourth of the total, meaning they are by
no means rare. Bicyclists in particular differ from motorcyclists in that they are not obligated to wear helmets,
which is believed to be why they had a higher rate of injury to the head and face compared with motorcyclists.
(With dooring accidents, in general there are believed to be injuries from collisions with the door itself, as wellas injuries from collisions with the road surface and other objects thereafter, but here no distinction has been
made between these.)
Rate for the no. of accidents

50％

Rate for the no. of accidents

Rate for the no. of accidents■Collision (danger perception) speed (four-wheeled vehicles and motorcycles)
For dooring accidents, at what sorts of speeds are motorcycles traveling when they collide?
Fig. 5 shows the rate for the number of accidents by danger perception speed in 2014.
(Since figures on bicycle speed cannot be obtained from the accident data, this is only listed for four-wheeledvehicles and motorcycles.)To start with, the doors of four-wheeled vehicles are essentially only opened and closed when the vehicle isstopped. For motorcycles, the highest rate of collisions occur at 10km/h – 20km/h, which account for morethan half of the total, and the majority of the collisions occur at 30km/h or slower. This is believed to bebecause motorcyclists ride by decreasing their speed to a certain extent in cases like when they are passing
by beside stopped vehicles.

100％
Motorcycles

21％

80％

Bicycles

60％

95％

40％

■Trip purpose
When dooring accidents occurred, for what purpose were the four-wheeled vehicle and bicycle / motorcycle
driving around?
Fig. 8 shows the rate for the number of accidents by trip purpose in 2014. For four-wheeled vehicles,
accidents while working accounted for more than half of the accidents, though there was by no means a
shortage of accidents from visiting / picking-up and while shopping. Conversely, with bicycles / motorcycles
accidents while commuting to work, shopping, and visiting / picking-up stood out. It can be surmised that the
four-wheeled vehicles were busy and the bicycles / motorcycles were in a rush on their way to work, and so
dooring accidents conceivably become more liable to occur when both sides are pressed for time.
60％

4％
Fatality

Serious injury

No injury

Noncounterparty

41％

30％

20％

20％

15％

0％
Slight injury

4W vehicles

40％

20％
0％

Motorcycles

50％

10％

74％

Bicycles54％

Rate for the no. of accidentslSpeciafeature

18％

11％

7％

4％
3％
Work

16％

Commu- Commu- Tourism / Dining
ting
ting recreational
to work to school
travelShopping Visiting/ Going to Visiting
picking-up hospital hometown

Other

Degree of personal injury

Trip purpose

Fig. 6. Rate for the no. of accidents by degree of personal injury (2014)

Fig. 8. Rate for the no. of accidents by trip purpose (2014)

ITARDA INFORMATION no.114

ITARDA INFORMATION no.114

Dooring accidents by parked or stopped vehicles~ Stopped vehicles can pose a danger ~ITARDA INFORMATION no.114

100％

98％

4W vehicles

80％

Motorcycles

96％

60％

62％

Motorcycles
Bicycles

38％

40％

30％

24％

25％
20％

8％

10％

11％
6％

5％

5％

Chest Stomach Back

Hips

53％
0％

40％

25％

18％

20％

All
Head
injuries

Face

Neck

Arms

Legs

Major points of personal injury

SuﬀoNo-cation / injury
drowning, etc.

Noncounterparty

Fig. 7. Rate for the no. of accidents by major point of personal injury (2014)
0％

While
stopped

〜10

〜20

〜30

〜40

〜50

Over 50 Unable toascertain

Danger perception speed (km/h)
Fig. 5. Rate for the no. of accidents by danger perception speed (2014)■Degree of personal injury and major points of personal injury
To what degree are people injured by dooring accidents?
Fig. 6 shows the rate for the number of accidents by degree of personal injury in 2014. Fortunately, mostdooring accidents only resulted in slight injuries, but some cases of severe injuries were also seen. There
were no such accidents in 2014 that resulted in fatalities, but over the past ten years between about zero andfour such accidents have occurred each year.
Fig. 7 shows the rate for the number of accidents by major points of personal injury in 2014. It reveals thatmost of the injuries were slight injuries in degree, and were concentrated mainly among rider’s arms and legs.
Furthermore, the rate of injuries to areas above the neck came to one-fourth of the total, meaning they are by
no means rare. Bicyclists in particular differ from motorcyclists in that they are not obligated to wear helmets,
which is believed to be why they had a higher rate of injury to the head and face compared with motorcyclists.
(With dooring accidents, in general there are believed to be injuries from collisions with the door itself, as wellas injuries from collisions with the road surface and other objects thereafter, but here no distinction has been
made between these.)
Rate for the no. of accidents

50％

Rate for the no. of accidents

Rate for the no. of accidents■Collision (danger perception) speed (four-wheeled vehicles and motorcycles)
For dooring accidents, at what sorts of speeds are motorcycles traveling when they collide?
Fig. 5 shows the rate for the number of accidents by danger perception speed in 2014.
(Since figures on bicycle speed cannot be obtained from the accident data, this is only listed for four-wheeledvehicles and motorcycles.)To start with, the doors of four-wheeled vehicles are essentially only opened and closed when the vehicle isstopped. For motorcycles, the highest rate of collisions occur at 10km/h – 20km/h, which account for morethan half of the total, and the majority of the collisions occur at 30km/h or slower. This is believed to bebecause motorcyclists ride by decreasing their speed to a certain extent in cases like when they are passing
by beside stopped vehicles.

100％
Motorcycles

21％

80％

Bicycles

60％

95％

40％

■Trip purpose
When dooring accidents occurred, for what purpose were the four-wheeled vehicle and bicycle / motorcycle
driving around?
Fig. 8 shows the rate for the number of accidents by trip purpose in 2014. For four-wheeled vehicles,
accidents while working accounted for more than half of the accidents, though there was by no means a
shortage of accidents from visiting / picking-up and while shopping. Conversely, with bicycles / motorcycles
accidents while commuting to work, shopping, and visiting / picking-up stood out. It can be surmised that the
four-wheeled vehicles were busy and the bicycles / motorcycles were in a rush on their way to work, and so
dooring accidents conceivably become more liable to occur when both sides are pressed for time.
60％

4％
Fatality

Serious injury

No injury

Noncounterparty

41％

30％

20％

20％

15％

0％
Slight injury

4W vehicles

40％

20％
0％

Motorcycles

50％

10％

74％

Bicycles54％

Rate for the no. of accidentslSpeciafeature

18％

11％

7％

4％
3％
Work

16％

Commu- Commu- Tourism / Dining
ting
ting recreational
to work to school
travelShopping Visiting/ Going to Visiting
picking-up hospital hometown

Other

Degree of personal injury

Trip purpose

Fig. 6. Rate for the no. of accidents by degree of personal injury (2014)

Fig. 8. Rate for the no. of accidents by trip purpose (2014)

ITARDA INFORMATION no.114

ITARDA INFORMATION no.114

lSpeciafeatureDooring accidents by parked or stopped vehicles~ Stopped vehicles can pose a danger ~ITARDA INFORMATION no.114■Age group and sex
With dooring accidents, who tends to be the perpetrators and the victims in said accidents?
Figs. 9 and 10 show the rates for numbers of accidents by age group for four-wheeled vehicles and bicycles /motorcycles in 2014. For four-wheeled vehicles, the older men get, the more their accident rate increases,
with men between the ages of 60 – 69 having the most accidents. With women, this peaks between the agesof 40 – 49, and tends to gradually decrease before and after this. For men, this is believed to be due tofactors like the effect of aging on transportation workers, and for women it is presumably due to factors likethe high frequency of vehicle use for purposes such as picking up children and shopping during theirchild-rearing years. The steep drop-off in the graph for men aged 70 and over is assumed to be from theretirement of transportation workers. Conversely, with bicycles / motorcycles for men the peak is between theages of 30 – 39, then the rate of accidents decreases the older they get, which represents the opposite
phenomena than that for four-wheeled vehicles. With women, there is a slight increase from their 20s throughtheir 40s, but after that this tends to shift downward. There is a sizable gap between students and youths, with
one conceivable cause for this being the different routes they take, as many of the former travel on sidewalks
and many of the latter travel on roadways.
30％

Rate for the no. of accidents

Male
Female25％■Human factors
What sorts of human factors give rise to dooring accidents?
Figs. 11 and 12 show the rate for the number of accidents by human factors for four-wheeled vehicles andbicycles / motorcycles in 2014. As for human factors with four-wheeled vehicles, the majority of these werecaused by failure to confirm safety factors in one’s surroundings. In the case examples from micro-studies,
there seemed to be numerous cases where people just opened their door unthinkingly without paying any
particular attention when doing so. Conversely, with bicycles / motorcycles, cases where there were no
human factors accounted for more than half of the total, followed by failure to observe surrounding traffic
movement (neglecting to pay close attention), failure to confirm safety factors, and failure of prediction (errors
in judgment). For bicycles / motorcycles, it is not easy to accurately recognize the actions of the people within
a four-wheeled vehicle by looking through the window glass, so it is difficult to predict whether or not the door
will open. Moreover, as far as matters that drivers of four-wheeled vehicles must observe are concerned, in
the Road Traffic Act, Chapter 4. Obligations for Drivers and Users, Section 1. Obligations for Drivers (Items
Drivers Must Comply With), Article 71 it states: “Drivers of vehicles must comply with the items listed below.”
The third of the four items listed here says: “Drivers must take the necessary steps to ensure that they do notopen their door or exit the vehicle without first confirming that it is safe to do so, and to ensure that the otherpassengers riding in the vehicle with them do not cause traffic hazards through such conduct.” Therefore,
when not only the drivers of four-wheeled vehicles themselves but also their passengers go to open theirdoors, it is important that they soundly check to confirm whether or not any approaching vehicles (people) arein the vicinity.

20％

Operating error
Failure ofprediction

15％

1％

5％

Failure to observe
surrounding traﬃcmovement
12 or under

13 ‒ 1920 ‒ 2930 ‒ 3940 ‒ 49

50 ‒ 59

60 ‒ 691％

70 or overAge group (4W vehicles)
Fig. 9. Rate for the no. of accidents by age group for four-wheeled vehicles (2014)

1％

1％

Failure ofprediction

10％

2014
2,010
accidents
Failure to conﬁrm safety factors

30％
Male

Rate for the no. of accidents

Other

1％

10％

0％

Other

96％

Female25％

Fig. 11. Rate for the no. of accidents
by human factors forthe four-wheeled vehicle (2014)

20％
15％

Failure toobservesurrounding
traﬃcmovement

25％

2014
2,010
accidents

No human factor

52％

Failure to
conﬁrmsafety factors

12％Fig. 12. Rate for the no. of accidents
by human factors forbicycle / motorcycle (2014)

10％
5％
0％

12 or under

13 ‒ 1920 ‒ 2930 ‒ 3940 ‒ 49

50 ‒ 59

60 ‒ 69

70 or overAge group (bicycles / motorcycles)
Fig. 10. Rate for the no. of accidents by age group for bicycles / motorcycles (2014)

ITARDA INFORMATION no.114

ITARDA INFORMATION no.114

lSpeciafeatureDooring accidents by parked or stopped vehicles~ Stopped vehicles can pose a danger ~ITARDA INFORMATION no.114■Age group and sex
With dooring accidents, who tends to be the perpetrators and the victims in said accidents?
Figs. 9 and 10 show the rates for numbers of accidents by age group for four-wheeled vehicles and bicycles /motorcycles in 2014. For four-wheeled vehicles, the older men get, the more their accident rate increases,
with men between the ages of 60 – 69 having the most accidents. With women, this peaks between the agesof 40 – 49, and tends to gradually decrease before and after this. For men, this is believed to be due tofactors like the effect of aging on transportation workers, and for women it is presumably due to factors likethe high frequency of vehicle use for purposes such as picking up children and shopping during theirchild-rearing years. The steep drop-off in the graph for men aged 70 and over is assumed to be from theretirement of transportation workers. Conversely, with bicycles / motorcycles for men the peak is between theages of 30 – 39, then the rate of accidents decreases the older they get, which represents the opposite
phenomena than that for four-wheeled vehicles. With women, there is a slight increase from their 20s throughtheir 40s, but after that this tends to shift downward. There is a sizable gap between students and youths, with
one conceivable cause for this being the different routes they take, as many of the former travel on sidewalks
and many of the latter travel on roadways.
30％

Rate for the no. of accidents

Male
Female25％■Human factors
What sorts of human factors give rise to dooring accidents?
Figs. 11 and 12 show the rate for the number of accidents by human factors for four-wheeled vehicles andbicycles / motorcycles in 2014. As for human factors with four-wheeled vehicles, the majority of these werecaused by failure to confirm safety factors in one’s surroundings. In the case examples from micro-studies,
there seemed to be numerous cases where people just opened their door unthinkingly without paying any
particular attention when doing so. Conversely, with bicycles / motorcycles, cases where there were no
human factors accounted for more than half of the total, followed by failure to observe surrounding traffic
movement (neglecting to pay close attention), failure to confirm safety factors, and failure of prediction (errors
in judgment). For bicycles / motorcycles, it is not easy to accurately recognize the actions of the people within
a four-wheeled vehicle by looking through the window glass, so it is difficult to predict whether or not the door
will open. Moreover, as far as matters that drivers of four-wheeled vehicles must observe are concerned, in
the Road Traffic Act, Chapter 4. Obligations for Drivers and Users, Section 1. Obligations for Drivers (Items
Drivers Must Comply With), Article 71 it states: “Drivers of vehicles must comply with the items listed below.”
The third of the four items listed here says: “Drivers must take the necessary steps to ensure that they do notopen their door or exit the vehicle without first confirming that it is safe to do so, and to ensure that the otherpassengers riding in the vehicle with them do not cause traffic hazards through such conduct.” Therefore,
when not only the drivers of four-wheeled vehicles themselves but also their passengers go to open theirdoors, it is important that they soundly check to confirm whether or not any approaching vehicles (people) arein the vicinity.

20％

Operating error
Failure ofprediction

15％

1％

5％

Failure to observe
surrounding traﬃcmovement
12 or under

13 ‒ 1920 ‒ 2930 ‒ 3940 ‒ 49

50 ‒ 59

60 ‒ 691％

70 or overAge group (4W vehicles)
Fig. 9. Rate for the no. of accidents by age group for four-wheeled vehicles (2014)

1％

1％

Failure ofprediction

10％

2014
2,010
accidents
Failure to conﬁrm safety factors

30％
Male

Rate for the no. of accidents

Other

1％

10％

0％

Other

96％

Female25％

Fig. 11. Rate for the no. of accidents
by human factors forthe four-wheeled vehicle (2014)

20％
15％

Failure toobservesurrounding
traﬃcmovement

25％

2014
2,010
accidents

No human factor

52％

Failure to
conﬁrmsafety factors

12％Fig. 12. Rate for the no. of accidents
by human factors forbicycle / motorcycle (2014)

10％
5％
0％

12 or under

13 ‒ 1920 ‒ 2930 ‒ 3940 ‒ 49

50 ‒ 59

60 ‒ 69

70 or overAge group (bicycles / motorcycles)
Fig. 10. Rate for the no. of accidents by age group for bicycles / motorcycles (2014)

ITARDA INFORMATION no.114

ITARDA INFORMATION no.114

(Akio Takahashi)

イタルダインフォメーションに関するお問い合せ先

渉外事業課

TEL 03-5577-3973

FAX 03-5577-3980

公益財団法人 交通事故総合分析センター●ウェブサイト http://www.itarda.or.jp/ ●Eメール koho@itarda.or.jp●フェイスブック http:facebook.com/itarda.or〒101-0064 東京都千代田区猿楽町2-7-8 住友水道橋ビル8階
TEL 03-5577-3977(代表) FAX 03-5577-3980

ITARDA INFORMATION no.114

つくば 交通事故調査事務所

67％

60%

2014
2,325 accidents

50%

40%

30%

20%

19％
7％

10%

3％

3％

P

he
Ot

res ians
l
o
c
s
r
y
ot e
st
M cycl Bic ede

r

0

s

11

70%

le

27

住 友 水 道 橋 ビル８ 階

The first thing I remember learning in the skills training at driving school was: “When exiting the vehicle, you must
check to see whether or not there are any vehicles approaching from behind before opening your door.” Now that
I once again recall this matter from back when I first began learning how to drive, I would like to go back to basics
and tie this in with promoting safer driving.
Incidentally, driving schools in the Netherlands teach students to open doors by twisting their body to use thehand on the opposite side of their body away from the door to open it. By instilling this habit in them, it makes it
so that drivers can naturally check to see if there are any bicycles or the like behind them.

~ Stopped vehicles can pose a danger ~ic

Postscript

Dooring accidents by parked
or stopped vehiclesvehBicyclists / motorcyclists should also make efforts to ensure that they do not end up as victims.
・ They should refrain from passing between vehicles stuck in traffic to the extent possible, while also
reducing their speed appropriately.
・ When passing beside four-wheeled vehicles, they should leave enough space between them.
・ They should pay attention to what the people inside of four-wheeled vehicles are doing while thevehicle is parked or stopped.

lSpeciafeatureMotorcycles and bicycles
No.114tend to overwhelmingly
be at risk of encountering
a dooring accident!
公益財団法人 交通事故総合分析センター〒101 0064 東 京 都 千 代 田 区 猿 楽 町 ２ ７ ８

Based on the analysis results of the human factors, to start with it will be necessary to get drivers of four-wheeledvehicles to soundly check for safety.
・ When opening doors, drivers should get in the habit of opening them after first checking to make sure it is safe
to do so around them.
・ In order to expand their range of visibility, drivers should proactively make use of their rear-view mirror andside-view mirrors.
・ When opening doors, they should start by opening them a little, then opening them slowly, rather than throwing
them open all at once.
・ When drivers have passengers riding with them, they should encourage their passengers to pay attention byconfirming their surroundings in advance, while getting on and off.
・ They should be attentive to pedestrians and baby strollers and the like passing beside their vehicle,
even in parking lots.

交通事故分析レポート No.114

4W■To decrease accidents

ITARDA INFORMATION

Rate for the no. of accidents

・ Bicycles account for the majority of the counterparts to dooring accidents at two-thirds of the total, followed
next by motorcycles at 20%.
・ When it comes to collisions with four-wheeled vehicles, most of these were collisions from the rear. As for thecollision rates with the left and right doors, with bicycles the rate was equivalent for both sides while formotorcycles the rate for the left door was four-times greater than that for the right door.
・ The collision speed for motorcycles is 30km/h or slower in most cases, of which more than half of the cases
were between 10km/h and 20km/h.
・ In most cases the degree of personal injury amounted to slight injuries, with the points of injury concentrated
mainly in arms and legs. However, cases where people were injured in the neck and higher accounted for
one-fourth of the total.
・ The trip purposes for four-wheeled vehicles mainly consisted of work in most cases, whereas for bicycles /motorcycles this often included commuting to work, shopping, and visiting / picking up.
・ For men driving four-wheeled vehicles, the accident rate increases as they get older, whereas for men on
bicycles / motorcycles it peaks in their 30s and then declines thereafter as they get older. For women driving
four-wheeled vehicles this peaks in their 40s, then gradually decreases before and after this, while for womenon bicycles / motorcycles this increases slightly from their 20s through their 40s, before starting to decline
again after this.
・ Human factors for four-wheeled vehicles are mostly due to failure to confirm safety factors. With bicycles /motorcycles there are no human factors in more than half of the cases, followed by failure to observe
surrounding traffic movement, failure to confirm safety factors, and failure of prediction.

ITARDA INFORMATION■Characteristics of the analysis results

交通事故分析レポート

4 Conclusion

イタルダ インフォメーション

Rate for the no. of accidents from being dooredby a four-wheeled vehicle by type of party (2014)

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