Part 5 of 8 in General Legislation & Driver Requirements

Your car's blind spot and setting your mirrors

Blind spot in a car: even with well-adjusted mirrors you do not see everything. Check mirrors and blind spot before every sideways move.

Written by Reviewed by Dirk van Zuijlen

Updated Reviewed on 3 min read

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On this page Your car's blind spot and setting your mirrors
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Every car has a blind spot: an area next to and diagonally behind you that you do not see in your mirrors. Here you read where a car’s blind spot is, how to set your mirrors and how to check the blind spot before you move sideways.

What is the blind spot of a car?

You see area 2 in the left door mirror. Areas 1 and 3 fall outside that mirror view: that is the blind spot.
You see area 2 in the left door mirror. Areas 1 and 3 fall outside that mirror view: that is the blind spot.

The blind spot is the area around your car that you cannot see: not directly through the windows and not in your mirrors. A cyclist, scooter, motorcycle or car can be there without you seeing it.

How big the blind spot is depends on your car, how you sit and how your mirrors are set. A lorry or a car with a trailer has a much bigger blind spot. Read more about the blind spot of a lorry.

Where is the blind spot on a car?

A car’s blind spot is mainly to your left and right, diagonally behind the car. Traffic there is just outside your door mirror and not yet in the corner of your eye. The pillars between the windows can also hide a cyclist or pedestrian.

The blind spot is most dangerous when you move sideways: pulling away, turning, merging and changing lanes. That applies on the motorway and in a residential street.

How to check your blind spot

Green is what you see in your mirrors. Red is the blind spot: you cannot see the red car on the left in your mirror. So take a quick look over your shoulder.
Green is what you see in your mirrors. Red is the blind spot: you cannot see the red car on the left in your mirror. So take a quick look over your shoulder.
  • Look in your mirrors regularly, so you know what is behind you.
  • Just before you move sideways, take a quick look over your shoulder into the blind spot.
  • Signal in good time. It is a sign for others, not permission to go.
  • In doubt? Wait and look again.

An empty mirror does not mean that nobody is next to you. A blind spot warning light or camera helps, but does not replace looking. See blind spot detection.

How to set your car mirrors to reduce the blind spot

This is how the left door mirror should be set: the horizon runs through the middle and you just see a small part of your own car.
This is how the left door mirror should be set: the horizon runs through the middle and you just see a small part of your own car.

Set your mirrors before you drive off. This is how:

  1. First sit properly, in your normal driving position.
  2. Interior mirror: you see the whole rear window.
  3. Door mirrors up or down: the horizon, where the ground and the sky meet, runs through the middle of the mirror. You see roughly half sky and half road.
  4. Door mirrors sideways: angle the mirror so that you just see a small part of the side of your car. The rest of the mirror shows the road next to and behind you.

Clean dirty or snowy mirrors. Is a mirror broken so that you cannot see well? Have it fixed first. An extra blind spot mirror is not required on a normal car. It helps, but even with such a mirror you still look over your shoulder.

Blind spot with a caravan or trailer

A wide caravan or trailer can block the view in your mirrors. Then use extended door mirrors, so you can look past the caravan to the rear. Only seeing the side of the caravan is not enough.

This caravan is wider than the car. With extended door mirrors you can look past the caravan to the rear.
This caravan is wider than the car. With extended door mirrors you can look past the caravan to the rear.

Practise like the exam

Example questions like in the CBR exam

Real questions from the Theorio app. You can expect similar questions in your CBR exam.

Question 1 of 6

Which part is called the blind spot?

Tap the answer you think is right.

Answer options

Answers and explanations for the example questions

  1. Question 1: Which part is called the blind spot?

    Correct answer: Part 3

    The blind spot is the area not visible in your mirrors. Part 3 cannot be seen in your mirrors. ⚠️

  2. Question 2: Which part can you see well in your side mirror?

    Correct answer: Part 2

    In the side mirrors, part 2 is clearly visible, as it allows you to see the traffic next to and diagonally behind you.

  3. Question 3: Which part can you see in your rearview mirror?

    Correct answer: Part 1

    In the rearview mirror, part 1 is visible, allowing you to observe the traffic directly behind you. This can sometimes be blocked by luggage or people in the back seat.

  4. Question 4: Can you completely eliminate the blind spot with well-adjusted mirrors?

    Correct answer: No

    Your mirrors are very important. If they are positioned correctly, you can see a lot. But you never see everything. There is always a piece next to the car that you cannot see. A bicycle or another car could be driving there. That piece is called the blind spot. That’s why just looking in the mirror is not enough. You should always look over your shoulder. Turn your head well. Then you will see the traffic in the blind spot.

  5. Question 5: Is the blind spot of a truck larger than that of a passenger car?

    Correct answer: Yes

    The answer is: Yes. Here is the explanation: A truck is very large and tall. The driver sits far above the road. He cannot see well what is happening right next to his wheel. He also cannot see what is behind the vehicle. That area where he sees nothing is called the blind spot. Because the vehicle is so large, that area is also very large. Much larger than with a regular car. So be very careful next to a truck!

  6. Question 6: Which part can you see best?

    Correct answer: Part 2

    Through the side mirrors, you can see part 2 the best. Part 1 is visible in the rearview mirror, but if someone is sitting in the back, that view can be blocked. Part 3 is located in the blind spot.

FAQ

Frequently asked questions

Short answers to questions that often come up on this subject.

When do you need extra wide wing mirrors?

When your caravan or trailer is wider than your car. In your normal wing mirrors you then only see its side, not the traffic behind it.

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