Traffic signsWorldwide

Learn traffic rules with clear explanations and visual examples in our illustrated book, designed to make studying simple and engaging.


401. Vehicle inspection

A vehicle inspection is an official check to determine whether a vehicle is safe, roadworthy and compliant with applicable technical and environmental requirements. Depending on the country and type of vehicle, inspections may check the brakes, tyres, steering, suspension, lights, emissions, identification and other safety-related components. Inspection rules and intervals vary between countries: some vehicles require regular periodic inspections, while others may also need an inspection after major modifications, an accident, importation or a change of ownership.

Vehicle inspection
Roller brake test at a vehicle inspection station.
Wikimedia.org • Roman Zázvorka • CC BY-SA
What is a vehicle inspection?

A vehicle inspection is an official examination of a vehicle to check whether it meets applicable safety, technical and environmental requirements.

What is checked during a vehicle inspection?

The inspection may include the brakes, tyres, steering, suspension, lights, vehicle identification and emissions. The exact inspection points depend on the country, vehicle type and type of inspection.

How often does a vehicle need to be inspected?

The inspection interval depends on the country and type of vehicle. Some countries require annual inspections, while others use longer intervals based on the vehicle's age, use or condition.

What happens if a vehicle fails the inspection?

A vehicle that does not meet the required standards may need to be repaired and presented for another inspection. Serious defects may restrict or prohibit the vehicle from being used until they are repaired.

Do all countries have the same vehicle inspection rules?

No. Vehicle inspection systems differ between countries, including which vehicles must be inspected, how often inspections are required and which technical standards are checked.

Do electric vehicles need a vehicle inspection?

In countries with periodic vehicle inspections, electric vehicles are generally also subject to inspection. Some inspection points differ because electric vehicles do not have a conventional combustion engine or exhaust-emission system.

402. Key

A key is a device used to unlock a vehicle and authorise its operation. Traditional vehicle keys use a mechanical blade, while modern vehicles commonly use electronic transponders, remote-control key fobs or keyless systems that communicate electronically with the vehicle.

Many modern keys work together with an immobiliser that prevents the engine or propulsion system from being activated unless an authorised key is detected. Replacement or duplicate keys may therefore need to be electronically programmed to the vehicle.

Key
Car keys of a Porsche, Ferrari and BMW.
Wikimedia.org • chen chin • CC BY
What does a modern car key do?

A modern car key can unlock and lock the vehicle and authorise the engine or electric propulsion system to start. It may use a mechanical blade, electronic transponder, remote-control functions or a keyless system.

What is a transponder key?

A transponder key contains an electronic identification device that communicates with the vehicle's immobiliser. If the correct code is not recognised, the vehicle normally prevents the engine or propulsion system from being started.

What should you do if you lose a vehicle key?

Use a spare key if available and arrange a replacement through an appropriate dealer, locksmith or vehicle specialist. Modern replacement keys often need to be programmed to the vehicle's electronic security system.

403. Dashboard

The dashboard is the area in front of the driver that displays important information about the vehicle and provides access to controls and warning indicators. It commonly includes the speedometer, fuel or battery level, warning lights, indicators and information about the engine, brakes and safety systems. Modern vehicles may use a digital instrument display instead of traditional gauges. Drivers should understand the main dashboard symbols and respond appropriately when a warning light appears.

What is a car dashboard?

The dashboard is the panel in front of the driver that displays vehicle information and contains controls, gauges and warning indicators.

What information is shown on the dashboard?

A dashboard may show the speed, fuel or battery level, engine information, warning lights, turn indicators and safety-system status. The exact display depends on the vehicle.

What do dashboard warning light colours mean?

Colours generally indicate the importance or function of a dashboard light. Red often indicates a serious warning, yellow or amber usually indicates caution, and green or blue commonly indicates that a system is active. Symbols and meanings can differ between vehicles, so consult the vehicle manual.

What should I do if a dashboard warning light comes on?

Identify the warning and follow the instructions in the vehicle manual. A red warning light may require you to stop safely as soon as possible, while other warnings may indicate that the vehicle should be checked or repaired.

What is the instrument cluster?

The instrument cluster is the part of the dashboard directly in front of the driver that contains the main gauges, displays and warning lights.

Can a dashboard be completely digital?

Yes. Many modern vehicles use a digital dashboard or digital instrument cluster that displays vehicle information on one or more electronic screens instead of traditional analogue gauges.

404. Windscreen wiper

A windscreen wiper is a device that removes rain, snow, dirt and other moisture from a vehicle’s windscreen to maintain a clear view of the road. Most vehicles use electrically powered wipers with replaceable rubber blades and several operating speeds, often together with a windscreen washer system. Drivers should replace worn or damaged wiper blades when they leave streaks, skip across the glass or no longer clean the windscreen effectively.

Parallelogram windscreen-wiper mechanism on a Porsche 904.
Wikimedia.org • Lothar Spurzem • CC BY-SA
What is a windscreen wiper?

A windscreen wiper is a device that moves across the windscreen to remove rain, snow, dirt and moisture so the driver can maintain a clear view of the road.

Why are windscreen wipers important?

Windscreen wipers help maintain clear visibility in bad weather and when the windscreen becomes dirty. Poor visibility can make it harder to detect traffic, pedestrians, signs and hazards.

When should windscreen wiper blades be replaced?

Wiper blades should be replaced when they are worn, cracked, damaged or no longer clean the windscreen effectively. Common signs include streaking, skipping, squeaking or areas of the windscreen remaining wet.

What is the windscreen washer system?

The windscreen washer system sprays cleaning fluid onto the windscreen so the wipers can remove dirt and improve visibility.

Can you drive with broken windscreen wipers?

Driving with defective windscreen wipers can be unsafe and may be illegal where functioning wipers are required. The driver must be able to maintain adequate visibility through the windscreen.

Do cars have a rear window wiper?

Many vehicles have a rear window wiper, especially hatchbacks, estate cars and SUVs. Whether one is fitted or legally required depends on the vehicle design and applicable regulations.

405. Doors

Doors provide access to the vehicle and help protect occupants while the vehicle is moving. They must open and close correctly, remain securely closed during driving and have functioning hinges, catches and locking mechanisms. Damaged or loose doors can create a serious safety risk, especially if they can open unexpectedly or cannot be closed properly.

Open car door from a Honda Civic Type R.
Wikimedia.org • Guyon • CC BY
Why are vehicle doors important for safety?

Vehicle doors help protect occupants and keep them safely inside the vehicle. They should close securely and must not open unexpectedly while driving.

What parts of a vehicle door should work correctly?

The door, hinges, catches, locking mechanism and surrounding structure should be secure and in good condition so the door can open and close properly.

Can you drive with a door that does not close properly?

A door that cannot remain securely closed can be dangerous and may make the vehicle unroadworthy. It should be repaired before the vehicle is used.

Are sliding doors checked differently from normal doors?

The basic requirement is the same: the door must open and close correctly and remain securely closed. The exact inspection method can depend on the type of door and vehicle.

Can damaged door hinges be dangerous?

Yes. Damaged, loose or badly worn hinges can prevent a door from closing correctly or allow it to move unexpectedly.

406. Glovebox

A glovebox, also called a glove compartment, is a storage compartment built into the dashboard in front of the passenger seat. It is commonly used to keep vehicle documents, the owner’s manual and other small items within easy reach. The glovebox should be kept closed while driving so that it does not obstruct passengers or allow loose objects to fall into the vehicle. Avoid storing valuables or items that can be damaged by the high temperatures that may develop inside a parked car.

An open glovebox with owner's manual and documents.
Wikimedia.org • Q4RadioGuy • CC BY
What is a glovebox?

A glovebox is a storage compartment in the dashboard, usually located in front of the passenger seat. It is also called a glove compartment.

Why is it called a glovebox?

The name comes from the early use of the compartment for storing driving gloves. Today it is commonly used for vehicle documents and other small items.

What can you keep in a glovebox?

A glovebox is commonly used for vehicle documents, the owner’s manual and small useful items. What should be kept in the vehicle depends on local legal requirements and personal preference.

Should the glovebox be closed while driving?

Yes. Keeping the glovebox properly closed while driving prevents it from obstructing the passenger area and helps stop loose objects from falling out.

Should valuables be kept in the glovebox?

It is generally better not to leave valuable or sensitive items in an unattended vehicle, as a glovebox does not provide strong protection against theft.

Can a glovebox become hot?

Yes. The interior of a parked vehicle can become very hot, and the glovebox can also heat up. Avoid storing heat-sensitive or potentially dangerous items there.

407. Visibility

Visibility is the ability of a driver to see the road, other road users and potential hazards clearly, while also making the vehicle visible to others. Visibility can be reduced by darkness, fog, rain, snow, dirty or misted windows, glare and objects that obstruct the driver’s view. Drivers should keep windows, mirrors and lights clean, remove anything that blocks their field of vision and use the appropriate vehicle lights when visibility is reduced.

Visibility
Experimental long-exposure photograph of moving car traffic.
Wikimedia.org • Rick Doble • CC BY-SA
What does visibility mean when driving?

Visibility describes how clearly a driver can see the road, traffic and hazards and how easily other road users can see the vehicle.

What can reduce visibility while driving?

Visibility can be reduced by darkness, fog, rain, snow, glare, dirty or misted windows and objects that obstruct the driver’s view.

How can you improve visibility while driving?

Keep the windscreen, windows, mirrors and lights clean, remove condensation or ice before driving and use the appropriate lights when conditions require them.

Can objects inside a vehicle obstruct visibility?

Yes. Objects placed on the dashboard, windscreen or elsewhere around the driver can block part of the field of vision and make it harder to detect road users or hazards.

What should you do when visibility is poor?

Reduce your speed, increase your following distance and use the appropriate lights. Make sure you can see far enough ahead to react safely to traffic and obstacles.

Why are mirrors important for visibility?

Mirrors extend the driver’s view to the rear and sides of the vehicle. They should be clean and correctly adjusted, although drivers must still check blind spots where necessary.

408. Snow

Snow can make roads slippery, reduce visibility and greatly increase stopping distances. Drivers should reduce speed, increase their following distance and accelerate, steer and brake smoothly to avoid losing control. Snow or ice should be removed from the windows, mirrors and lights before driving, and suitable tyres or other winter equipment may be required depending on the country and road conditions.

Snow
Car driving along Northeast Entrance Road between tall snowbanks in Yellowstone National Park. (United States)
Wikimedia.org • Jim Peaco • CC0
How does snow affect driving?

Snow can reduce tyre grip, visibility and vehicle control and increase the distance needed to slow down or stop.

How should you drive on snow?

Drive more slowly, increase your following distance and use smooth acceleration, steering and braking. Sudden movements can cause the tyres to lose grip.

Should snow be removed from a vehicle before driving?

Yes. Remove snow and ice that obstruct the windscreen, windows, mirrors and lights. Snow should also be removed where it could fall from the vehicle and create a hazard for other road users.

Are winter tyres required when it snows?

This depends on the country. Some countries require winter tyres during certain periods or winter conditions, while others only recommend them.

When are snow chains used?

Snow chains can provide additional grip on roads covered with snow or ice. Rules for their use vary between countries, and some roads may require them when indicated by a traffic sign.

Should you use fog lights during snowfall?

Fog-light rules vary by country. They are generally intended for conditions where snow, fog or other weather significantly reduces visibility, so drivers should follow the applicable local rules.

409. Ice

Ice can make a road extremely slippery and significantly reduce tyre grip, steering control and braking performance. Ice may be difficult to see, especially when it forms a thin transparent layer known as black ice. Drivers should reduce speed, increase their following distance and accelerate, steer and brake smoothly. Extra caution is needed on bridges, shaded roads and other places where ice may remain even when surrounding roads appear clear.

Ice
Bridge-icing warning sign beside an icy road. (United States)
Wikimedia.org • Petelewisr • CC0
Why is ice dangerous when driving?

Ice can cause a major loss of tyre grip, making it harder to steer, brake or accelerate without skidding.

What is black ice?

Black ice is a thin, transparent layer of ice that can be difficult to distinguish from the road surface. It is particularly dangerous because drivers may not notice it until the vehicle begins to lose grip.

How should you drive on an icy road?

Reduce speed, increase your following distance and use smooth steering, acceleration and braking. Avoid sudden movements that could cause the tyres to lose grip.

Where is ice most likely to form on a road?

Ice can form anywhere temperatures are sufficiently low, but drivers should be particularly careful on bridges, shaded sections, exposed roads and areas where water collects.

What should you do if the vehicle starts to skid on ice?

Remain calm, avoid sudden braking or steering and make smooth corrections while reducing the forces that caused the loss of grip. The correct response can depend on the vehicle and its safety systems.

Do winter tyres improve grip on ice?

Winter tyres can provide better grip in cold and winter conditions than summer tyres, although no tyre can eliminate the risk of skidding on ice. Requirements for winter tyres vary between countries.

410. Rain

Rain can reduce visibility, tyre grip and vehicle control while increasing stopping distances. Water on the road can also cause aquaplaning, where the tyres lose contact with the road surface. Drivers should reduce speed, increase their following distance, avoid sudden steering or braking and use the appropriate lights when visibility is reduced. Extra care is needed during heavy rain and when water collects in wheel tracks or on poorly drained roads.

Rain
Driving on a wet road during heavy rain.
Wikimedia.org • Oregon Department of Transportation • CC BY
How does rain affect driving?

Rain can reduce visibility and tyre grip, increase stopping distances and make it more difficult to control the vehicle safely.

What is aquaplaning?

Aquaplaning occurs when a layer of water builds up between the tyres and the road, causing the tyres to lose contact with the road surface and reducing steering and braking control.

How should you drive in heavy rain?

Reduce speed, increase your following distance and use smooth steering, acceleration and braking. Use the appropriate lights and be prepared for reduced visibility and standing water.

Why should you increase the following distance in rain?

Wet roads can increase the distance needed to stop. A larger following distance gives you more time and space to react safely.

What should you do if the vehicle starts aquaplaning?

Remain calm, ease off the accelerator and avoid sudden braking or steering. Make smooth corrections until the tyres regain contact with the road.

Should you use headlights in rain?

Lighting requirements vary between countries. Drivers should use the lights required by local traffic rules whenever rain or other conditions reduce visibility.

411. Freezing rain

Freezing rain occurs when supercooled raindrops freeze on contact with cold roads, vehicles and other surfaces, creating a thin layer of ice. This can make roads extremely slippery even when they appear wet rather than frozen. Drivers should reduce speed, increase their following distance and avoid sudden acceleration, steering or braking. Bridges, shaded sections and untreated roads can become particularly hazardous, and conditions may change quickly as freezing rain continues.

Freezing rain
Freezing rain and snow at night along Kinross Circle. (Fairfax County, Virginia, United States)
Wikimedia.org • Famartin • CC BY-SA
What is freezing rain?

Freezing rain is rain that freezes when it reaches a sufficiently cold surface, forming a layer of ice on roads, vehicles and other objects.

Why is freezing rain dangerous for drivers?

Freezing rain can create very slippery and difficult-to-see ice, greatly reducing tyre grip and making steering and braking more difficult.

Is freezing rain the same as snow?

No. Snow falls as frozen crystals, while freezing rain falls as liquid droplets that freeze when they reach a cold surface.

Can freezing rain cause black ice?

Yes. Freezing rain can create a thin, transparent layer of ice that is difficult to distinguish from a wet road and is often described as black ice.

How should you drive in freezing rain?

Reduce speed, increase your following distance and use smooth acceleration, steering and braking. Avoid unnecessary driving if conditions become extremely slippery.

Where is freezing rain most dangerous?

Extra caution is needed on bridges, exposed roads, shaded areas and untreated surfaces, where ice may form quickly or remain longer.

412. Fog

Fog can greatly reduce visibility and make it difficult to judge speed, distance and the position of other road users. Drivers should reduce speed, increase their following distance and use the appropriate lights without dazzling others. Avoid relying only on the vehicle ahead as a guide, and be prepared for sudden changes in visibility. When fog is very dense, stopping in a safe place may be the best option.

Country road disappearing into dense fog.
Wikimedia.org • Sylwia Pietruszka • CC0
Why is fog dangerous when driving?

Fog can greatly reduce visibility and make it harder to judge speed, distance and the movement of other road users.

How should you drive in fog?

Reduce speed, increase your following distance and use the appropriate lights. Drive so that you can stop safely within the distance you can clearly see.

Should you use high-beam headlights in fog?

Usually not. High beams can reflect from the water droplets in fog and make visibility worse. Use the lighting permitted and recommended under local traffic rules.

When should fog lights be used?

Fog lights are intended for conditions where fog or similar weather significantly reduces visibility. The exact rules for front and rear fog lights vary between countries.

Should you follow the lights of the vehicle ahead in fog?

No. You should maintain your own safe speed and following distance. Following another vehicle too closely can be dangerous because visibility and stopping distance remain limited.

What should you do if fog becomes extremely dense?

If visibility becomes too poor to continue safely, slow down and consider stopping at a safe place away from moving traffic until conditions improve.

413. Hail

Hail can reduce visibility, make the road slippery and create sudden hazardous driving conditions. Hailstones may accumulate on the road and reduce tyre grip in a similar way to ice or loose material, while larger hailstones can also damage windscreens and vehicle bodywork. Drivers should reduce speed, increase their following distance, avoid sudden steering or braking and, when conditions become severe, consider stopping at a safe place until the hailstorm passes.

Hail
Hailstorm in San Jose. (California, United States)
Wikimedia.org • quinn norton • CC BY
Why is hail dangerous when driving?

Hail can reduce visibility and tyre grip, make the road slippery and distract drivers because of the sudden noise and impact of hailstones.

How should you drive during a hailstorm?

Reduce speed, increase your following distance and use smooth steering and braking. If the hail becomes severe or visibility is very poor, consider stopping at a safe place away from moving traffic.

Can hail make a road slippery?

Yes. Hailstones can collect on the road and create a slippery surface with reduced tyre grip, particularly when mixed with rain or melting ice.

Can hail damage a vehicle?

Yes. Large hailstones can damage windscreens, windows, mirrors and vehicle bodywork. Severe hail can also reduce visibility if glass becomes cracked or damaged.

Should you use headlights during hail?

Use the lights required by local traffic rules when hail or other weather reduces visibility. Lighting requirements vary between countries.

Is it safer to stop during severe hail?

If visibility or road conditions become too dangerous, it may be safer to stop at a suitable place away from moving traffic and continue when conditions improve.

414. Sunlight

Sunlight can reduce visibility when the sun is low in the sky or when bright light reflects from wet roads, snow, buildings or other vehicles. Sun glare can make traffic lights, signs, pedestrians and other road users difficult to see. Drivers should reduce speed when necessary, keep the windscreen clean, use the sun visor or suitable sunglasses and leave extra space to react to hazards that may be temporarily hidden by glare.

Sunlight
Sunrise over a street in Cabo San Lucas. (Baja California Sur, Mexico)
Wikimedia.org • Frank Contreras Cardenas • CC BY-SA
Why can sunlight be dangerous when driving?

Bright or low sunlight can cause glare and temporarily reduce visibility, making traffic lights, signs, pedestrians and other road users more difficult to see.

When is sun glare most likely to cause problems?

Glare is often strongest when the sun is low in the sky, particularly around sunrise and sunset, and when sunlight reflects from wet roads, snow, glass or other bright surfaces.

What should you do when sunlight makes it difficult to see?

Reduce speed and increase your following distance so you have more time to react. Use the sun visor where helpful and avoid continuing at a speed that is too high for the available visibility.

Can a dirty windscreen make sun glare worse?

Yes. Dirt, grease, dust and streaks on the glass can scatter bright sunlight and make glare much worse. Keep the windscreen clean inside and outside.

Can sunglasses help while driving in bright sunlight?

Suitable sunglasses can reduce glare and improve visual comfort in bright conditions. They should not be so dark that they significantly reduce visibility, especially when entering tunnels or shaded areas.

Does a sun visor improve visibility?

Yes. A correctly positioned sun visor can block direct sunlight without unnecessarily obstructing the driver’s view of the road.

415. Sunglasses

Sunglasses can reduce glare and improve visual comfort when driving in bright sunlight, especially when the sun is low or reflects from wet roads, snow or other surfaces. Drivers should choose lenses that allow traffic lights, signs and other road users to remain clearly visible. Very dark lenses can reduce visibility in tunnels, at night or in changing light conditions, so sunglasses should be removed when they make it harder to see the road safely.

Sunglasses
Canadian musician Daniel Wesley wearing sunglasses.
Wikimedia.org • Vancouver 125 • CC BY
Can sunglasses help when driving?

Yes. Sunglasses can reduce glare and improve visual comfort in bright sunlight, making it easier to see the road and surrounding traffic.

When are sunglasses most useful while driving?

They are particularly useful when the sun is low in the sky or when bright light reflects from wet roads, snow, glass or other surfaces.

Are very dark sunglasses suitable for driving?

Very dark lenses can reduce the amount of light reaching the eyes and may make it difficult to see in tunnels, shade, poor weather or at night. Sunglasses should not interfere with safe visibility.

Can you wear sunglasses at night?

Sunglasses generally reduce available light and can therefore make it harder to see at night. They should not be worn when they significantly reduce visibility.

Are polarised sunglasses useful for driving?

Polarised lenses can reduce reflections from roads and other flat surfaces, but they may make some digital displays or screens harder to read. Drivers should make sure all essential instruments remain clearly visible.

Should sunglasses be removed when entering a tunnel?

If the lenses make the darker environment difficult to see, remove the sunglasses when it is safe to do so. Drivers should always maintain adequate visibility as lighting conditions change.

416. Salt

Salt is commonly used for deicing and anti-icing roads in winter. It lowers the freezing point of water, helping to prevent ice from forming or to melt existing snow and ice. Road authorities may spread dry salt, wet salt or brine before or during freezing conditions. Salt improves road safety, but drivers should still reduce speed and adapt to slippery conditions because treated roads can remain hazardous, especially during heavy snowfall, freezing rain or very low temperatures.

Salt
Workers spreading road salt from a salt truck. (Milwaukee, Wisconsin, United States)
Wikimedia.org • Michael Pereckas • CC BY
Why is salt used on roads in winter?

Salt helps lower the freezing point of water, making it harder for ice to form and helping existing snow or ice melt.

What is the difference between deicing and anti-icing?

Anti-icing means treating the road before ice forms, while deicing means applying salt or another treatment after snow or ice is already present.

What is road brine?

Brine is a solution of salt and water that can be sprayed onto roads before freezing conditions occur. It helps the salt begin working quickly and can reduce ice formation.

Does salt make an icy road completely safe?

No. Salt can improve grip by reducing snow and ice, but treated roads can still be slippery. Drivers should continue to reduce speed and increase their following distance.

Does road salt work in every temperature?

No. The effectiveness of salt decreases as temperatures become very low. Road authorities may use different treatments or methods depending on the weather and road conditions.

Can road salt damage a vehicle?

Repeated exposure to road salt can contribute to corrosion of metal parts, particularly underneath the vehicle. Washing accumulated salt from the vehicle can help reduce this effect.

417. Air conditioning

Air conditioning helps control the temperature and humidity inside a vehicle and can improve comfort and visibility. In hot weather it cools the passenger compartment, while in damp conditions it can help remove moisture from the air and clear mist from the windows more quickly. Drivers should use the system in a way that keeps the interior comfortable without creating large temperature differences, and the system should be maintained so that it continues to work effectively.

Air conditioning button in a car.
Wikimedia.org • Mattes • CC0
What does air conditioning do in a car?

Air conditioning cools and dehumidifies the air inside the vehicle, helping improve comfort and reduce moisture on the windows.

Can air conditioning help demist the windscreen?

Yes. Because air conditioning removes moisture from the air, it can help clear condensation from the windscreen and windows more quickly.

Should air conditioning be used in winter?

Yes. Air conditioning can still be useful in winter because it reduces humidity inside the vehicle and can help demist the windows.

Does air conditioning increase fuel or energy consumption?

Yes. Operating the air-conditioning system requires energy and can increase fuel or electricity consumption, although the effect depends on the vehicle, system and conditions.

Should a car's air conditioning be maintained?

Yes. Regular use and maintenance can help keep the system effective. A poorly functioning system may cool less efficiently or fail to remove moisture properly.

Can you drive without air conditioning?

Yes, in many vehicles and countries air conditioning itself is not required. However, the driver must still maintain adequate visibility and safe conditions inside the vehicle.

418. Hydroplaning

Hydroplaning, also called aquaplaning, occurs when a layer of water builds up between a vehicle’s tyres and the road surface, causing the tyres to lose contact with the road. Steering, braking and acceleration can then become much less effective. The risk increases with speed, standing water and worn tyres. Drivers should reduce speed in heavy rain, avoid sudden steering or braking and make sure their tyres are in good condition with sufficient tread depth.

Hydroplaning
A vehicle hydroplaning due to flash-flooding. (Wagga Wagga, Australia)
Wikimedia.org • Bidgee • CC BY-SA
What is hydroplaning?

Hydroplaning occurs when water separates the tyres from the road surface, reducing or temporarily removing normal tyre grip.

What causes hydroplaning?

The risk increases with higher speed, standing water, worn tyres and insufficient tyre tread. Tyre pressure and road conditions can also affect the risk.

How can you reduce the risk of hydroplaning?

Reduce speed in heavy rain, avoid driving through deep standing water where possible and keep your tyres properly maintained with sufficient tread depth.

What should you do if your vehicle starts hydroplaning?

Remain calm, ease off the accelerator and avoid sudden braking or steering. Keep the steering movements smooth and controlled until the tyres regain contact with the road.

Can worn tyres increase the risk of hydroplaning?

Yes. Tyre grooves help move water away from the contact area. Worn tyres can remove less water, increasing the risk of losing grip on a wet road.

At what speed does hydroplaning occur?

There is no single speed at which hydroplaning always begins. The risk depends on speed, water depth, tyre condition, tyre pressure and the road surface.

419. Loose chippings

Loose chippings are small stones or gravel lying on the road surface, often after roadworks or surface treatment. They can reduce tyre grip, increase braking distance and be thrown into the air by passing vehicles, potentially damaging windscreens or other vehicles. Drivers should reduce speed, increase their following distance and avoid sudden acceleration, braking or steering. Extra space should also be kept from other vehicles where loose stones may be projected from their tyres.

Warning for loose chippings on the road. (Haute-Savoie, France)
Wikimedia.org • Marc Mongenet • CC BY-SA
What are loose chippings?

Loose chippings are small stones or pieces of gravel lying loose on the road surface, often after resurfacing or road maintenance.

Why are loose chippings dangerous?

Loose stones can reduce tyre grip and vehicle control and may be thrown into the air by tyres, potentially damaging windscreens or other vehicles.

How should you drive on loose chippings?

Reduce speed, increase your following distance and avoid sudden acceleration, braking or steering. Keep additional space from other vehicles where stones may be thrown up by their tyres.

Can loose chippings increase stopping distance?

Yes. Loose material between the tyres and road can reduce available grip, making braking and steering less effective.

Why are loose chippings common after roadworks?

Some road-surfacing methods use a layer of small stone aggregate. Until the material settles or excess stones are removed, loose chippings may remain on the surface.

Can loose chippings damage a vehicle?

Yes. Stones thrown up by tyres can cause chips or cracks in windscreens, headlights and vehicle paintwork.

420. Blind spot

A blind spot is an area around a vehicle that the driver cannot see directly or through the mirrors. Blind spots vary with the size and design of the vehicle and can be particularly large around trucks, buses and other high-sided vehicles. Drivers should adjust their mirrors correctly and check beside the vehicle before changing lanes, turning or moving away. Cyclists, pedestrians and motorcyclists should also avoid remaining beside large vehicles where the driver may not be able to see them.

Blind spots and mirrors inside a truck.
Wikimedia.org • Piero • CC BY-SA
What is a blind spot?

A blind spot is an area around a vehicle that cannot be seen directly by the driver or adequately through the mirrors.

Do all vehicles have blind spots?

Yes. The size and position of blind spots depend on the vehicle design, mirrors and driver position. Large vehicles generally have larger blind spots than passenger cars.

How should you check a blind spot?

Adjust the mirrors correctly and, where necessary, make a brief direct check beside the vehicle before changing lanes, turning or moving away. The exact technique depends on the vehicle.

Why are truck blind spots dangerous?

Trucks can have large areas around the front, sides and rear that are difficult or impossible for the driver to see. Cyclists and pedestrians can therefore disappear from view even when they are close to the vehicle.

Can mirrors eliminate every blind spot?

No. Correctly adjusted mirrors can greatly improve visibility, but some areas may still remain difficult to see. Drivers should use all available mirrors and direct observation where appropriate.

Where should cyclists avoid riding near a truck?

Cyclists should avoid remaining directly beside, immediately in front of or close behind a large vehicle, particularly near intersections where the vehicle may turn.

421. Distraction

Distraction is anything that takes a driver’s attention away from safely controlling the vehicle and observing the road. Common distractions include mobile phones, navigation systems, passengers, eating, adjusting controls or looking away from traffic. Distraction can be visual, manual or mental and may significantly increase reaction time. Drivers should keep their attention on the road, prepare navigation and other settings before moving and avoid activities that interfere with safe driving.

Distraction
Distracted driving kills, keep your eyes and mind on the road.
Wikimedia.org • Melissa Wenger • CC0
What is distracted driving?

Distracted driving occurs when a driver's visual, manual or mental attention is diverted from driving and the surrounding traffic.

What are common driving distractions?

Common distractions include mobile phones, navigation systems, passengers, eating, adjusting vehicle controls and looking away from the road.

Why is using a phone while driving dangerous?

Using a phone can combine visual, manual and mental distraction, reducing the driver's ability to notice hazards and react quickly.

Can hands-free phone use still be distracting?

Yes. Even when the driver's hands remain on the wheel, a conversation can create mental distraction and reduce attention to traffic.

Can a navigation system distract a driver?

Yes. Entering destinations or repeatedly looking at a screen can divert attention from the road. Set the route before driving whenever possible and use voice guidance where helpful.

How can you reduce distractions while driving?

Prepare navigation and vehicle settings before moving, secure loose objects, keep your phone away from unnecessary use and focus continuously on the road and traffic.

422. Emotions

Emotions can influence attention, judgement and driving behaviour. Anger, stress, fear, sadness or excitement may cause a driver to become distracted, impatient or more likely to take risks. Strong emotions can also affect concentration and reaction time. Drivers should recognise when their emotional state is interfering with safe driving and, if necessary, slow down, take a break or stop in a safe place until they feel able to continue calmly and attentively.

Emotions
Driver showing frustration while stuck in traffic congestion.
Wikimedia.org • Raysonho • CC0
Can emotions affect driving?

Yes. Strong emotions can affect attention, judgement, reaction time and decision-making, which can make safe driving more difficult.

Why is anger dangerous when driving?

Anger can lead to impatience, aggressive manoeuvres, speeding or reduced attention. Drivers should avoid reacting emotionally to other road users.

Can stress affect concentration while driving?

Yes. Stress can make it harder to focus on traffic and process information calmly, especially in complex or busy situations.

What should you do if you are too emotional to drive safely?

If your emotional state is affecting concentration or judgement, stop or delay the journey when possible and continue only when you feel able to drive safely.

Can excitement also be a distraction?

Yes. Positive emotions such as excitement can still reduce concentration or encourage impulsive behaviour if they take attention away from driving.

How can you stay calm while driving?

Allow enough travel time, avoid reacting to aggressive drivers, keep a safe distance and take a break when stress or frustration becomes difficult to manage.

423. Road rage

Road rage is aggressive, hostile or intimidating behaviour by a road user toward others in traffic. It can include excessive honking, tailgating, shouting, threatening gestures, blocking another vehicle or making deliberately aggressive manoeuvres. Anger can reduce judgement and increase risk-taking, turning a minor traffic conflict into a dangerous situation. Drivers should avoid confrontation, remain calm, keep a safe distance and never retaliate against aggressive behaviour.

Road rage
Photo illustration of a driver demonstrating road rage. (Camp Pendleton, California, United States)
Wikimedia.org • DaleHulm • CC BY-SA
What is road rage?

Road rage is aggressive, hostile or intimidating behaviour directed at other road users, often caused by anger or frustration in traffic.

What are examples of road rage?

Examples can include tailgating, excessive honking, shouting, threatening gestures, deliberately blocking another vehicle or aggressive overtaking and lane changes.

Why is road rage dangerous?

Anger can reduce judgement and encourage impulsive or risky driving, increasing the chance of collisions and escalating conflicts between road users.

What should you do if another driver becomes aggressive?

Stay calm, avoid confrontation, maintain a safe distance and do not retaliate or copy the other driver's behaviour. If necessary, move away from the situation when it is safe to do so.

Should you stop to confront an aggressive driver?

Generally, no. Confrontation can make the situation more dangerous. It is usually safer to remain in your vehicle and create distance from the aggressive road user.

How can you avoid road rage?

Allow enough travel time, accept that other road users make mistakes, avoid competing for road space and focus on reaching your destination safely rather than reacting emotionally.

424. Health

Health can affect a person’s ability to drive safely. Illness, injury, poor vision, reduced mobility, fatigue, certain medical conditions and some medicines can interfere with concentration, reaction time, judgement or vehicle control. Drivers should recognise when their physical or mental condition may make driving unsafe and should seek medical advice when necessary. In some countries, specific health conditions must be reported and may require a medical examination or restrictions on the driving licence.

Health
Older person seated behind the wheel of a car.
Wikimedia.org • Shixart1985 • CC BY
How can health affect driving?

Health problems can affect vision, concentration, reaction time, judgement, coordination and vehicle control, making safe driving more difficult.

Should you drive when you are ill?

Not if the illness makes it difficult to concentrate, react quickly or control the vehicle safely. Drivers should delay the journey or seek medical advice when necessary.

Can medication affect driving?

Yes. Some medicines can cause drowsiness, dizziness, blurred vision or slower reactions. Always follow the instructions provided with the medicine and advice from a healthcare professional.

Can poor eyesight affect driving?

Yes. Good vision is essential for recognising traffic signs, road users, hazards and changes in traffic conditions. Many countries set minimum eyesight requirements for drivers.

Can a medical condition affect a driving licence?

Yes. Depending on the country and condition, a driver may need a medical assessment, licence restriction or adapted vehicle before being permitted to drive.

Who is responsible for deciding whether someone is fit to drive?

This depends on local law. The driver usually has a responsibility to ensure they are fit to drive, while doctors or specialised assessment centres may evaluate driving fitness when required.

425. Epilepsy

Epilepsy is a neurological condition that can cause recurrent seizures, which may involve changes in awareness, movement, sensation or consciousness. Because a seizure can temporarily prevent a person from controlling a vehicle safely, epilepsy can affect driving fitness and driving-licence requirements. The rules vary between countries and usually depend on factors such as the type of seizure, how long the person has been seizure-free, treatment and medical assessment. Anyone who experiences a seizure should follow the applicable driving rules and seek medical advice before driving again.

Epilepsy
Anatomical diagram showing the principal fissures and lobes of the cerebrum.
Wikimedia.org • Henry Vandyke Carter • CC0
Can epilepsy affect your ability to drive?

Yes. A seizure can cause loss of awareness, consciousness or vehicle control, so epilepsy can affect whether a person is medically fit to drive.

Can a person with epilepsy have a driving licence?

In many countries, yes, provided specific medical and seizure-free requirements are met. The exact conditions depend on the country, licence category and individual medical situation.

What should you do after having a seizure?

Do not assume it is safe to continue driving. Seek medical advice and check the applicable driving-licence rules, because a temporary period without driving may be required.

Why is a seizure-free period required for driving?

A seizure-free period helps assess the risk of another seizure occurring while driving. The required period varies depending on the type and cause of the seizure and local regulations.

Can epilepsy medication affect driving?

Yes. Anti-seizure medicines can sometimes cause effects such as drowsiness, dizziness or reduced concentration. Changes in treatment can also affect seizure control, so medical advice should be followed.

Are driving rules stricter for professional drivers with epilepsy?

Usually, yes. Drivers of trucks, buses and vehicles used for certain professional transport generally face stricter medical fitness requirements because of the greater potential consequences of a seizure while driving.