Course Content 4 — Blind Spots and Driving

• What is visible from a two-wheeled vehicle and from a four-wheeled vehicle
• Examples of blind spots
• How to drive defensively
• How to communicate between vehicles

The road is a place of mixed traffic where many persons and vehicles proceed. To drive safely, acquiring skills in correct driving operations and driving according to traffic laws and regulations are a given. Further, a driver must judge the traffic conditions accurately in each instant, anticipate what hazards might be present, and take specific corresponding actions to drive more safely.

1. What Is Visible from a Two-Wheeled Vehicle and from a Four-Wheeled Vehicle

Among traffic accidents, the number of collisions between a two-wheeled vehicle and a four-wheeled vehicle is not insignificant. In order to prevent such accidents, it is important to understand how a two-wheeled vehicle appears to a driver of a four-wheeled vehicle, and how a four-wheeled vehicle appears to a driver of a two-wheeled vehicle. Drivers of four-wheeled vehicles tend to think lightly of two-wheeled vehicles, with their smaller vehicle body. Consequently, they might consider two-wheeled vehicles as things that travel at speeds similar to bicycles or could overlook them.

Further, when a two-wheeled vehicle and a four-wheeled vehicle are at the relative positions shown below, the driver of the two-wheeled vehicle might not be able to see the four-wheeled vehicle or not be able to anticipate its movement, and vice versa.

Cautions for the driver of a two-wheeled vehicle

• Do not enter the blind spots of a four-wheeled vehicle.
• Ensure a necessary distance, and in other ways travel in a position more likely to be noticed by the driver of the four-wheeled vehicle.
• Sufficiently check the traffic conditions at the rear to the right.

Cautions for the driver of a four-wheeled vehicle

• Like four-wheeled vehicles, two-wheeled vehicles cannot stop easily, either. Do not think of them as the same as bicycles.
• It is easy for a two-wheeled vehicle to enter a blind spot, and it is difficult to notice their presence. Check for safety sufficiently when changing course, etc.
• A two-wheeled vehicle might seem slower or appear farther than it actually is.

2. Examples of Blind Spots

In actual road traffic, there are many areas which are blind spots. Accident-free drivers are driving cautiously at all times, searching whether hazards are present in blind spots. On the other hand, when drivers who have caused accidents are asked for reasons:

• "I didn't think there would be a pedestrian behind the parked vehicle."
• "I didn't think there would be an oncoming vehicle in the curve."
• "I didn't think a vehicle would be coming from the right in the intersection."

...and other assumptions had been made that no other traffic would be present. Selfish judgments had been made instead of anticipating hazards in blind spots. It is important to pay attention to traffic which is not in the field of vision and traffic which is not seen at the moment and to check sufficiently whether there really is no traffic to be anticipated.

Reference — "Blind spot" Refers to an area or location that is not visible from the driver's seat.

1. Blind Spots of the Automobile Itself

Though there might be differences in the area, all automobiles have blind spots resulting from the structure of the automobile itself. To compensate for blind spots, safety standards of the Road Transport Vehicle Act mandates the installation of rearview mirrors and under mirrors. Be watchful of the surrounding conditions.

Blind Spots of an Automobile

(Approximate distances for a standard sedan:)

• Approx. 12 m ahead (front blind zone)
• Approx. 7 m to front-left diagonal
• Approx. 1 m immediately to the front
• Approx. 4 m to each side
• Approx. 4 m to the rear-left and rear-right diagonals

※ The size of a blind spot is different depending on the type of vehicles or the build of the driver.

Reference — "Under mirror" Refers to a mirror for checking for safety below or below to the left (or below to the right for vehicles with the steering wheel on the left) immediately in front of the vehicle to prevent accidents of hitting unseen traffic when starting to move or when parking.

Attention — Blind spots of pillars and side mirrors

Blind spots created by the automobile's pillars

Front pillars and rear pillars are not wide, but they create large blind spots hiding pedestrians and two-wheeled vehicles that are far away. The front pillars create blind spots hiding crossing pedestrians, and the rear pillars create blind spots hiding bicycles and two-wheeled vehicles that are to the rear diagonally. Move the head a little to check the blind spots due to pillars.

Blind spots of mirrors

Some areas are not visible in the rearview mirrors. It is important to look with own eyes when turning right or left or changing course instead of relying solely on mirrors, because it is especially easy for two-wheeled vehicles to the rear diagonally to the left or right to be in blind spots.

2. Blind Spots Created by Parked Vehicles

① Blind spots created by vehicles parked or stopped on both sides

There are always blind spots created by parked and stopped vehicles. Especially when vehicles are parked and stopped on both sides, blind spots are created on both sides and the difficulty of discovering pedestrians, etc. is higher than when vehicles are parked or stopped on one side. A driver must pay attention to both sides.

② Blind spots created by a continuous row of parked and stopped vehicles

When vehicles are parked or stopped in a continuous row, the area of a blind spot is larger than when a single vehicle is parked or stopped, and there is a row of them, increasing the hazard.

③ Blind spots in the case of identifying preschool children

Since preschool children are short, it is easy for them to be in a blind spot, even if the parked or stopped vehicle is a passenger vehicle.

3. Blind Spots at Intersections

① Blind spot to the left

Since drivers of two-wheeled vehicles travel along the left side, it is especially likely for them to delay in discovering a vehicle approaching from the left. At an intersection where visibility is poor, always come to a stop or proceed slowly and check for safety before proceeding.

② Blind spot for vehicles turning right

When turning right at an intersection, a blind spot is created behind an oncoming (or stopped) vehicle, and a two-wheeled vehicle in the blind spot might not be noticed.

③ Blind spot due to a short-cut turn

When turning right at an intersection, a short-cut turn enlarges the blind spot to the right, increasing the hazard.

Attention — Blind spot when turning left

A two-wheeled vehicle that has entered the blind spot on the left side of a four-wheeled vehicle might not be noticed.

4. Blind Spots Created by Curves

Curves with poor visibility have larger blind spots. Even on the same curve, the size of the blind spot is different depending on whether there is an obstacle present.

Attention — Blind spots of traffic mirrors Be careful. Even traffic mirrors have areas they cannot reflect.

3. How to Drive Defensively

Driving in a way that does not cause an accident is a must for a driver, but endeavoring to select the less hazardous driving behavior to try to "avoid being involved in an accident" is also important from the perspective of preventing accidents.

1. Speed That Is Ready for Hazards

A cause of many accidents is speeding. Should a hazard arise, speeding could prevent a driver from avoiding what could have been avoided. Travel at a safe speed and drive ready for hazards.

(The space to ensure safety with others changes according to speed — e.g., 30 km/h vs. 50 km/h)

2. Appropriate Road Position

To avoid causing an accident, it is important to choose a road position from which it is easier to notice vehicles and people. Further, to avoid being involved in an accident, it is important to:

• Not enter the blind spots of other vehicles
• Be easily seen by other vehicles
• Avoid a hazardous situation, should one occur

...and otherwise take an appropriate road position.

(Which road position is the best for noticing hazards?)

4. How to Communicate between Vehicles

Communication between vehicles is extremely important for the safety of traffic and driving in comfort. It is important to communicate intent as much as possible. These are not mandatory, but here are some ways communication between vehicles is being done using devices equipped on vehicles. These methods have not been designated and might mean different things according to the circumstances, so there is a need to take the surrounding conditions into account in deciphering what a vehicle that flashes its headlights, etc. is intending to do next.

① Flashing headlights at an intersection

An oncoming vehicle proceeding straight might reduce speed or come to a stop and flash its headlights at a vehicle waiting to turn right to indicate "you can go first". Just flashing the headlights could mean "I'm going first, so don't proceed".

② Turning on hazard lights

• Hazard lights might be turned on to inform following vehicles of congestion on an expressway, etc.
• When a vehicle is allowed in front of another vehicle during congestion, the vehicle allowed in might use its hazard lights to express appreciation.

③ Turn signal on a single road

When a vehicle ahead turns on its turn signal on a straight road, reduces speed, and moves to the left, it could be indicating "please overtake (or pass) me". There is a need to make sure before traveling.

④ Switching headlights

When approaching an intersection without traffic lights at night or when it is otherwise dark, a vehicle might proceed at low speed while switching its headlights between high and low beams to be noticed by other vehicles. Further, a vehicle might turn off its headlights when yielding the road to an oncoming vehicle where the road is narrow.

Let's Try — Course Content 4 — Check your understanding with right/wrong questions.

(See page 275 for answers.)

1. Drivers of two-wheeled and four-wheeled vehicles both should understand the characteristics of the other vehicle, yield to each other, and be considerate in their actions.
2. Pedestrians crossing from behind parked vehicles and two-wheeled vehicles proceeding behind four-wheeled vehicles proceeding straight when making a right turn can be considered potential hazards in traffic.
3. A two-wheeled vehicle may be overlooked by a driver of a four-wheeled vehicle or appear farther or seem slower than it actually is. Two-wheeled vehicles must pay special attention to four-wheeled vehicles turning right at an intersection.
4. Blind spots from the driver's seat are created only to the rear of the vehicle, so blind spots need attention only when reversing.

(正: right, 誤: wrong)