Alertness is about staying switched on behind the wheel: looking properly, knowing what is around you, and not letting phones, passengers or tiredness pull your attention away. In the theory test it covers mirrors, blind spots, signals, distractions and fatigue. On the road, it is the difference between seeing a cyclist in time and not seeing them at all.
Last reviewed: September 2026. Checked against the Highway Code and GOV.UK.
What this topic covers in the theory test
Alertness questions test whether you know how and when to observe, and what gets in the way of good observation. Expect questions on:
- using your mirrors before signalling, changing speed or changing direction
- blind spots, and when you need to look round rather than rely on mirrors
- what to do before moving off, turning or reversing
- mobile phones, sat navs and other in-car technology
- distractions such as loud music, eating or arguing
- driving when tired, and how to plan breaks on a long journey
- being dazzled by the sun or by headlights
- reading other road users’ signals, and why flashing headlights aren’t an instruction
Many of these rules also turn up in the video clip questions and in the hazard perception test, because spotting a hazard early depends on being alert in the first place.
Mirrors and the Mirrors-Signal-Manoeuvre routine
Rule 161 tells you to use your mirrors frequently so that you always know what is behind and to each side of you. You should check them in good time before you signal or change direction or speed. The Highway Code sums this up as “Mirrors – Signal – Manoeuvre”, usually shortened to MSM.
In practice, MSM means:
- Mirrors: check what is behind and alongside you, including cyclists and motorcyclists.
- Signal: if a signal would help someone, give it clearly and in good time.
- Manoeuvre: make the move only when it is safe, at a suitable speed and in the right position.
The same thinking applies when changing lanes. Rule 133 says to check your mirrors, take a sideways glance if necessary to check the blind spot, signal if it will help, then move over only when it is safe.
A common exam trap is thinking MSM is only for turning. It also applies before you slow down, stop, overtake or move off. If your speed or position is about to change, someone behind you needs to know.
Blind spots and looking round
Mirrors don’t show everything. The areas you can’t see in your mirrors are your blind spots, and a car, cyclist or motorcyclist can sit in one for several seconds.
Before moving off, Rule 159 says to use all mirrors to check the road is clear, look round to check the blind spots, signal if necessary, and take a final look round before you go. When turning right, Rule 180 tells you to check your mirrors and blind spot again before you turn, and to watch out for cyclists, motorcyclists and pedestrians.
Motorcyclists and cyclists are easy to miss. Rule 211 warns that they can be hard to see at junctions and may be coming towards you faster than you think. When you pull out, take a proper look in each direction and don’t let a quick glance become a habit.
Reversing needs extra observation. Under rule 202 you should use all your mirrors, check the blind spot behind you, and reverse slowly while looking mainly through the rear window and checking all around.
Concentration and distractions
Rule 148 states simply that safe driving needs concentration. It lists distractions to avoid, including loud music, trying to read maps, tuning a radio, arguing with passengers or other road users, eating and drinking, and smoking.
It also sets out legal rules on smoking. In England and Wales you must not smoke, or let anyone else smoke, in an enclosed private vehicle that is carrying someone under 18. Scotland has a similar law that applies to anyone aged 18 or over in a private vehicle with an under-18 present.
Sat navs and other screens are covered by rule 150. You must be in proper control of your vehicle at all times, and you shouldn’t let a map or screen distract you. If you need to change a route or setting, find a safe place to stop first. Driver assistance systems, such as lane departure warnings or motorway assist, are there to help, not to let you switch off. You remain responsible for the car.
Mobile phones: the law
Rule 149 is one of the most tested rules in this topic, and the law is stricter than many people realise. You must not use a hand-held mobile phone, or any similar device that can send or receive data, for any purpose while driving. That includes:
- making or receiving calls or texts
- checking the time, notifications or social media
- using the camera, music or a map on a hand-held phone
- picking the phone up to dial a number and then putting it in a cradle to talk
- using it while stationary in traffic, for example at red lights
The rule also applies to someone supervising a learner driver. There are narrow exceptions: you may call 999 or 112 in a genuine emergency when it is unsafe or impractical to stop, and you may make a contactless payment at a payment terminal while the vehicle is stationary.
Hands-free isn’t automatically safe. The Highway Code says hands-free equipment is also likely to distract your attention, and it is far safer not to use any phone while driving. Let calls go to voicemail and deal with them when you have parked somewhere safe.
Tiredness and planning breaks
Rule 91 explains that driving when tired greatly increases your risk of a collision. To reduce it:
- don’t begin a journey if you are tired, and get enough sleep before a long drive
- avoid long journeys between midnight and 6 am, when natural alertness is at its lowest
- plan sufficient breaks: a minimum break of at least 15 minutes after every two hours of driving is recommended
- if you feel sleepy, stop in a safe place
On a motorway, don’t stop in an emergency area or on the hard shoulder just because you are tired. Leave at the next exit or services instead. Signs of tiredness include yawning, heavy eyelids, drifting in your lane and not remembering the last few miles. Opening a window or turning up the radio doesn’t fix fatigue; a proper break does.
Glare, dazzle and signals from others
Being alert also means managing your vision. Rule 93 tells you to slow down, and if necessary stop, if you are dazzled by bright sunlight. Rule 94 says not to use tinted glasses, lenses or visors at night or in poor visibility if they restrict your vision. If an oncoming vehicle’s headlights dazzle you, rule 115 says to slow down or stop.
Other road users’ signals need reading, not blind trust. Rule 104 tells you to watch for signals given by others and only proceed when you are satisfied it is safe. Someone’s indicator might have been left on by mistake.
Flashing headlights are especially misleading. Under rule 110 they should only be used to let others know you are there. Rule 111 says never assume that flashing headlights are a signal inviting you to go. The driver might be flashing someone else, or might be warning you. Use your own judgement and look for yourself.
Common mistakes learners make
- Checking mirrors only when turning, not before slowing down or changing lanes.
- Relying on mirrors alone and skipping the blind spot check before moving off.
- Believing it is fine to use a hand-held phone while stopped at traffic lights. It isn’t.
- Thinking hands-free calls are risk-free. They are legal but still distracting.
- Treating a flash of headlights as permission to pull out.
- Pushing on through tiredness instead of stopping for a break.
- Adjusting a sat nav while moving instead of stopping first.
Quick-reference table
| Situation | What to do | Highway Code |
|---|---|---|
| Before moving off | Check all mirrors, look round for blind spots, signal if needed, final look | rule 159 |
| Before any change of speed or direction | Mirrors, Signal, Manoeuvre | rule 161 |
| Changing lanes | Mirrors, sideways glance if needed, signal, move when safe | rule 133 |
| Hand-held phone | Never while driving, including in stationary traffic (999/112 emergency exception) | rule 149 |
| Long journey | Break of at least 15 minutes after every two hours | rule 91 |
| Dazzled by the sun | Slow down, and stop if necessary | rule 93 |
| Someone flashes their headlights | Don’t assume it is an invitation; use your own judgement | rule 111 |
Practice questions
These practice questions are written by Get Driving Test Ready to help you revise. They are not official DVSA questions.
Q1. You're about to slow down to turn left into a side road. What should you do first?
A) Check your mirrors
B) Sound your horn to warn cyclists
C) Brake gently, then check your mirrors
D) Signal left, then check your mirrors
Answer: A. Check your mirrors in good time before you signal or change speed or direction. That is the Mirrors, Signal, Manoeuvre routine. (Highway Code rule 161)
Practise this on the road: Talk through Mirrors, Signal, Manoeuvre aloud with your instructor on your next few left turns, checking mirrors before signalling or slowing.
Q2. You're waiting in a queue of stationary traffic at red lights. Can you read a text on your hand-held phone?
A) Yes, because the car isn't moving
B) No, the ban on hand-held phones still applies
C) Yes, if the handbrake is on
D) Only if the engine is switched off by stop-start
Answer: B. You must not pick up or use a hand-held phone while stationary in traffic. The law applies whenever you're driving, including in queues. (Highway Code rule 149)
Practise this on the road: Before each lesson, put your phone on silent and out of reach, and agree with your supervisor that it stays there until you park.
Q3. When is it legal to use a hand-held phone while driving?
A) When driving below 20 mph
B) To call 999 or 112 in a genuine emergency when it is unsafe or impractical to stop
C) To answer a call from your driving instructor
D) To check your route on a map app
Answer: B. The Highway Code allows a hand-held call to 999 or 112 in a genuine emergency when it is unsafe or impractical to stop. None of the other reasons is an exception. (Highway Code rule 149)
Practise this on the road: Ask your instructor where you could safely stop to make an urgent call, and practise pulling over quickly and legally.
Q4. You're planning a five-hour drive. What does the Highway Code recommend?
A) A break of at least 15 minutes after every two hours of driving
B) No breaks, so you arrive sooner
C) One 30-minute break halfway through
D) A 5-minute break every hour
Answer: A. A minimum break of at least 15 minutes after every two hours of driving is recommended. (Highway Code rule 91)
Practise this on the road: On a longer practice drive, plan a break after two hours and discuss with your supervisor where to stop safely.
Q5. You feel sleepy while driving on a motorway. Where should you stop?
A) At the next services, or leave at the next exit
B) In the left-hand lane with hazard lights on
C) In an emergency area
D) On the hard shoulder
Answer: A. If you feel sleepy you should stop somewhere safe, but not in an emergency area or on the hard shoulder of a motorway. Leave at the next exit or services. (Highway Code rule 91)
Practise this on the road: Ask your supervisor to point out service areas and exits on a dual carriageway or motorway drive, and discuss when you would use them.
Q6. An oncoming driver flashes their headlights at you while you're waiting to turn right. What should you do?
A) Turn immediately, because they are letting you go
B) Sound your horn and wait
C) Flash your headlights back and go
D) Check it is safe for yourself before deciding whether to turn
Answer: D. Never assume flashing headlights are an invitation to proceed. The driver could mean something else, so rely on your own observations. (Highway Code rule 111)
Practise this on the road: When another driver flashes their lights, say what you can see and decide for yourself whether it is safe before moving.
Q7. What are blind spots?
A) Areas of the road with no street lights
B) Areas you can't see in your mirrors
C) Parts of the windscreen not cleared by the wipers
D) Stretches of road with no road markings
Answer: B. Blind spots are the areas you are unable to see in your mirrors, which is why you need to look round before moving off. (Highway Code rule 159)
Practise this on the road: Practise checking your blind spots with a look over your shoulder before moving off from the kerb, with your instructor watching.
Q8. Low sun is dazzling you as you drive. What should you do?
A) Slow down, and stop if necessary
B) Speed up to get past the glare quickly
C) Switch on your front fog lights
D) Put your hazard lights on and continue
Answer: A. If you are dazzled by bright sunlight, slow down and if necessary stop. (Highway Code rule 93)
Practise this on the road: On a drive towards low sun, practise using your sun visor early and easing off your speed, then discuss it with your instructor.
Q9. You want to enter a new postcode into your sat nav. When should you do it?
A) At a red traffic light
B) While moving slowly in town
C) When you've stopped in a safe place
D) While on a straight, quiet road
Answer: C. Don't let screen-based information distract you while driving. If you need to change a setting, find a safe place to stop first. (Highway Code rule 150)
Practise this on the road: Set up your sat nav route before you start driving, and practise finding a safe, legal place to stop if it needs changing.
Q10. Which of these is most likely to distract you while driving?
A) Scanning well ahead
B) Arguing with a passenger
C) Using your mirrors regularly
D) Keeping both hands on the wheel
Answer: B. The Highway Code lists arguing with passengers or other road users as a distraction to avoid, because safe driving needs concentration. (Highway Code rule 148)
Practise this on the road: Agree with your supervisor to keep chat light and the radio low during busy parts of a drive, and notice how it helps.
Next steps
Go back to the theory test hub for the full list of topics and how the test works. Related topics: hazard awareness, which builds on the observation skills here, and attitude, which covers how you respond to other road users. To put your alertness to the test with video clips, read our hazard perception test guide.