Blind spots and how to deal with them

Driver with head out of window seeing passing cyclist in their blind-spot.

Published 9 April 2021
Last updated 12 April 2021

What are blind spots and how do they affect your driving? In this blog, we look at how to check your blind spots when you're moving off and when you're on the move.

Think about this: you’re driving along on the motorway, keeping a good separation distance from the vehicles ahead of you, when you decide to speed up and overtake the lorry in front. You follow your usual procedure and check your mirrors before you signal to move out. As you start to make your manoeuvre, you hear a loud engine roar from a car travelling at speed in the lane to your right. You hastily return to the lane you were in and maintain your position until you feel confident enough to try again.

At this point, you might be saying to yourself, ‘Why did that happen?’ You followed the rules and yet you only managed to stop yourself from making a potentially dangerous decision at the last moment. The answer is that the other vehicle was in your blind spot.

What are blind spots?

A blind spot is an area that cannot be seen either when you’re looking ahead or when you’re checking your mirrors. The main blind spots are

  • the area between what you see as you look forward and what you see in your exterior mirror
  • the area obscured by the bodywork of your vehicle when you look in your mirrors. Vehicles of different shapes have different blind spots – for example, those caused by window pillars and head restraints.

Checking blind spots

Blind spots are just as likely to affect drivers who want to move off from a stationary position as drivers who are actually moving. In both cases, it’s essential for your safety, and that of other road users, to make some additional checks before you decide to take any action.

Moving off 

  • Check in your mirrors for activity behind you, then look around over your right shoulder before you move off. In some cases, it may help to wind down the window so you can get a better view.
  • Some vehicles have ‘assistive technology’ such as reverse-assist alarms. These devices might help reduce blind spots, but they will not remove them entirely. Always use your mirrors and glance over your shoulder before you commit to any decisions. 

On the move

  • Blind spots on the move are on either side of your vehicle. Do not look around to check for them – you’ll take your focus away from the road in front of you, with potentially dangerous consequences.
  • Regular and sensible use of your mirrors will keep you up to date with what’s happening behind. But you’ll still need to check your blind spots to gather as much information as possible before you make certain manoeuvres. You should take a quick sideways glance
  1. before you change lanes
  2. before you join a motorway or dual carriageway from a slip road
  3. when traffic is merging from the left or the right.
  • You should also recognise where other drivers’ blind spots will be and avoid remaining in them longer than necessary.

So there you have it: blind spots are only dangerous if you’re blind to their consequences … (Sorry!)

For more information about blind spots, mirrors and hazards, visit the Safe Driving for Life shop and pick up a copy of The Official DVSA Guide to Driving – the essential skills.

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