Dry Weather Driving Distances
Wet Weather Driving Distances
Increasing speed to join dual carriageways
Decreasing speed to join dual carriageways
Waiting in traffic
Help articles and highway code sections…
If you need to change lane, first use your mirrors and if necessary take a quick sideways glance to make sure you will not force another road user to change course or speed. When it is safe to do so, signal to indicate your intentions to other road users and when clear, move over.
You should follow the signs and road markings and get into the lane as directed. In congested road conditions do not change lanes unnecessarily. Merging in turn is recommended but only if safe and appropriate when vehicles are travelling at a very low speed, e.g. when approaching road works or a road traffic incident. It is not recommended at high speed.
A dual carriageway is a road which has a central reservation to separate the carriageways.
On a two-lane dual carriageway you should stay in the left-hand lane. Use the right-hand lane for overtaking or turning right. After overtaking, move back to the left-hand lane when it is safe to do so.
On a three-lane dual carriageway, you may use the middle lane or the right-hand lane to overtake but return to the middle and then the left-hand lane when it is safe.
Climbing and crawler lanes. These are provided on some hills. Use this lane if you are driving a slow-moving vehicle or if there are vehicles behind you wishing to overtake. Be aware of the signs and road markings which indicate the lane is about to end.
Cycle lanes. These are shown by road markings and signs. You MUST NOTdrive or park in a cycle lane marked by a solid white line during its times of operation. Do not drive or park in a cycle lane marked by a broken white line unless it is unavoidable. You MUST NOT park in any cycle lane whilst waiting restrictions apply.
Bus lanes. These are shown by road markings and signs that indicate which (if any) other vehicles are permitted to use the bus lane. Unless otherwise indicated, you should not drive in a bus lane during its period of operation. You may enter a bus lane to stop, to load or unload where this is not prohibited.
High-occupancy vehicle lanes and other designated vehicle lanes. Lanes may be restricted for use by particular types of vehicle; these restrictions may apply some or all of the time. The operating times and vehicle types will be indicated on the accompanying traffic signs. You MUST NOT drive in such lanes during their times of operation unless signs indicate that your vehicle is permitted (see ‘Traffic signs’).
Vehicles permitted to use designated lanes may or may not include cycles, buses, taxis, licensed private hire vehicles, motorcycles, heavy goods vehicles (HGVs) and high-occupancy vehicles (HOVs).
Where HOV lanes are in operation, they MUST ONLY be used by
- vehicles containing at least the minimum number of people indicated on the traffic signs
- any other vehicles, such as buses and motorcycles, as indicated on signs prior to the start of the lane, irrespective of the number of occupants.
One-way streets. Traffic MUST travel in the direction indicated by signs. Buses and/or cycles may have a contraflow lane. Choose the correct lane for your exit as soon as you can. Do not change lanes suddenly. Unless road signs or markings indicate otherwise, you should use
- the left-hand lane when going left
- the right-hand lane when going right
- the most appropriate lane when going straight ahead. Remember – traffic could be passing on both sides.
Wet weather. In wet weather, stopping distances will be at least double those required for stopping on dry roads (see ‘Typical stopping distances’). This is because your tyres have less grip on the road. In wet weather
- you should keep well back from the vehicle in front. This will increase your ability to see and plan ahead
- if the steering becomes unresponsive, it probably means that water is preventing the tyres from gripping the road. Ease off the accelerator and slow down gradually
- the rain and spray from vehicles may make it difficult to see and be seen
- be aware of the dangers of spilt diesel that will make the surface very slippery (see Annex 6: Vehicle maintenance, safety and security)
- take extra care around pedestrians, cyclists, motorcyclists and horse riders.
In winter check the local weather forecast for warnings of icy or snowy weather. DO NOT drive in these conditions unless your journey is essential. If it is, take great care and allow more time for your journey. Take an emergency kit of de-icer and ice scraper, torch, warm clothing and boots, first aid kit, jump leads and a shovel, together with a warm drink and emergency food in case you get stuck or your vehicle breaks down.
Before you set off
- you MUST be able to see, so clear all snow and ice from all your windows
- you MUST ensure that lights are clean and number plates are clearly visible and legible
- make sure the mirrors are clear and the windows are demisted thoroughly
- remove all snow that might fall off into the path of other road users
- check your planned route is clear of delays and that no further snowfalls or severe weather are predicted.
When driving in icy or snowy weather
- drive with care, even if the roads have been treated
- keep well back from the road user in front as stopping distances can be ten times greater than on dry roads
- take care when overtaking vehicles spreading salt or other de-icer, particularly if you are riding a motorcycle or cycle
- watch out for snowploughs which may throw out snow on either side. Do not overtake them unless the lane you intend to use has been cleared
- be prepared for the road conditions to change over relatively short distances
- listen to travel bulletins and take note of variable message signs that may provide information about weather, road and traffic conditions ahead.
Drive extremely carefully when the roads are icy. Avoid sudden actions as these could cause loss of control. You should
- drive at a slow speed in as high a gear as possible; accelerate and brake very gently
- drive particularly slowly on bends where loss of control is more likely. Brake progressively on the straight before you reach a bend. Having slowed down, steer smoothly round the bend, avoiding sudden actions
- check your grip on the road surface when there is snow or ice by choosing a safe place to brake gently. If the steering feels unresponsive this may indicate ice and your vehicle losing its grip on the road. When travelling on ice, tyres make virtually no noise.
High-sided vehicles are most affected by windy weather, but strong gusts can also blow a car, cyclist, motorcyclist or horse rider off course. This can happen on open stretches of road exposed to strong crosswinds, or when passing bridges or gaps in hedges.
In very windy weather your vehicle may be affected by turbulence created by large vehicles. Motorcyclists are particularly affected, so keep well back from them when they are overtaking a high-sided vehicle.
Before entering fog check your mirrors then slow down. If the word ‘Fog’ is shown on a roadside signal but the road is clear, be prepared for a bank of fog or drifting patchy fog ahead. Even if it seems to be clearing, you can suddenly find yourself in thick fog.
When driving in fog you should
- use your lights as required (see Rule 226)
- keep a safe distance behind the vehicle in front. Rear lights can give a false sense of security
- be able to pull up well within the distance you can see clearly. This is particularly important on motorways and dual carriageways, as vehicles are travelling faster
- use your windscreen wipers and demisters
- beware of other drivers not using headlights
- not accelerate to get away from a vehicle which is too close behind you
- check your mirrors before you slow down. Then use your brakes so that your brake lights warn drivers behind you that you are slowing down
- stop in the correct position at a junction with limited visibility and listen for traffic. When you are sure it is safe to emerge, do so positively and do not hesitate in a position that puts you directly in the path of approaching vehicles.
You MUST NOT use front or rear fog lights unless visibility is seriously reduced (see Rule 226) as they dazzle other road users and can obscure your brake lights. You MUST switch them off when visibility improves.
Keep your vehicle well ventilated to avoid drowsiness. Be aware that the road surface may become soft or if it rains after a dry spell it may become slippery. These conditions could affect your steering and braking. If you are dazzled by bright sunlight, slow down and if necessary, stop.
A level crossing is where a road crosses a railway or tramway line. Approach and cross it with care. Never drive onto a crossing until the road is clear on the other side and do not get too close to the car in front. Never stop or park on, or near, a crossing.
Overhead electric lines. It is dangerous to touch overhead electric lines. You MUST obey the safe height warning road signs and you should not continue forward onto the railway if your vehicle touches any height barrier or bells. The clearance available is usually 5 metres (16 feet 6 inches) but may be lower.
Controlled Crossings. Most crossings have traffic light signals with a steady amber light, twin flashing red stop lights (see ‘Light signals controlling traffic’and ‘Traffic signs’) and an audible alarm for pedestrians. They may have full, half or no barriers.
- You MUST always obey the flashing red stop lights.
- You MUST stop behind the white line across the road.
- Keep going if you have already crossed the white line when the amber light comes on.
- Do not reverse onto or over a controlled crossing.
- You MUST wait if a train goes by and the red lights continue to flash. This means another train will be passing soon.
- Only cross when the lights go off and barriers open.
- Never zig-zag around half-barriers, they lower automatically because a train is approaching.
- At crossings where there are no barriers, a train is approaching when the lights show.
Rule 293: Stop when the traffic lights show
Railway telephones. If you are driving a large or slow- moving vehicle, a long, low vehicle with a risk of grounding, or herding animals, a train could arrive before you are clear of the crossing. You MUST obey any sign instructing you to use the railway telephone to obtain permission to cross. You MUST also telephone when clear of the crossing if requested to do so.
Crossings without traffic lights. Vehicles should stop and wait at the barrier or gate when it begins to close and not cross until the barrier or gate opens.
User-operated gates or barriers. Some crossings have ‘Stop’ signs and small red and green lights. You MUST NOT cross when the red light is showing, only cross if the green light is on. If crossing with a vehicle, you should
- open the gates or barriers on both sides of the crossing
- check that the green light is still on and cross quickly
- close the gates or barriers when you are clear of the crossing.
If there are no lights, follow the procedure in Rule 296. Stop, look both ways and listen before you cross. If there is a railway telephone, always use it to contact the signal operator to make sure it is safe to cross. Inform the signal operator again when you are clear of the crossing.
Open crossings. These have no gates, barriers, attendant or traffic lights but will have a ‘Give Way’ sign. You should look both ways, listen and make sure there is no train coming before you cross.
Incidents and breakdowns. If your vehicle breaks down, or if you have an incident on a crossing you should
- get everyone out of the vehicle and clear of the crossing immediately
- use a railway telephone if available to tell the signal operator. Follow the instructions you are given
- move the vehicle clear of the crossing if there is time before a train arrives. If the alarm sounds, or the amber light comes on, leave the vehicle and get clear of the crossing immediately.
When the ‘Road Works Ahead’ sign is displayed, you will need to be more watchful and look for additional signs providing more specific instructions. Observe all signs – they are there for your safety and the safety of road workers.
- You MUST NOT exceed any temporary maximum speed limit.
- Use your mirrors and get into the correct lane for your vehicle in good time and as signs direct.
- Do not switch lanes to overtake queuing traffic.
- Take extra care near cyclists and motorcyclists as they are vulnerable to skidding on grit, mud or other debris at road works.
- Where lanes are restricted due to road works, merge in turn (see Rule 134).
- Do not drive through an area marked off by traffic cones.
- Watch out for traffic entering or leaving the works area, but do not be distracted by what is going on there. Concentrate on the road ahead, not the road works.
- Bear in mind that the road ahead may be obstructed by the works or by slow moving or stationary traffic.
- Keep a safe distance – there could be queues in front.
Law RTRA sect 16