This sign gives a clear instruction. You should prepare to negotiate a left-hand turn.

If any vehicle displaying a warning symbol is involved in an incident, the consequences could be serious. The emergency services need to be aware of how a dangerous or hazardous material will behave in different situations; for example, when it's wet.

If you attempt to move a casualty who has a spinal injury, it could cause further damage. Make sure an ambulance has been called for and talk to the casualty to keep them calm.

When passing horses, allow plenty of space, slow down and stop if you need to. Animals are easily frightened by sudden or loud noises and can quickly become uncontrollable, so don't sound your horn or rev the engine.

You must make sure that you adjust the seat so that you're able to reach all the controls and see in all the mirrors before you start to drive any vehicle. You should also be able to lean out of the window and check your offside blind spots.

Keeping the markings clear ensures that drivers and riders passing and children crossing have a clear, unrestricted view of each other.

If you overfill the engine with oil, you could cause the engine to build up too much pressure when it's running. This could cause damage to oil seals and gaskets.

Spilt diesel creates a serious risk to other road users, especially motorcyclists. Take care when refuelling and make sure that all filler caps and tank hatches are properly closed and secure.

Red diesel is subject to less excise duty than standard diesel, so it's considerably cheaper. It may only be used for authorised purposes. Any driver whose vehicle is found to be using this fuel illegally faces penalties.

Horse riders often keep to the outside of the roundabout even if they're turning right. Give them room in case they have to cross lanes of traffic.

Always allow plenty of time for your journey, in case of unforeseen problems such as punctures, breakdowns, road closures or diversions. You'll feel less stressed and less inclined to take risks if you're not under time pressure.

Horses and their riders will move more slowly than other road users. They might not have time to cut across heavy traffic to take up a position in the offside lane when they're turning right; it could also be hazardous for them to do so. Therefore, a horse and rider may approach a roundabout in the left-hand lane, even though they're turning right.

Air-brake systems are fitted with a warning device that operates if the air pressure in the tanks drops below a safe level. There may be a warning buzzer and/or pressure gauges. You must be aware of the function of all gauges on your vehicle, and check them as you drive.

Maintenance of the fifth wheel should be carried out regularly, ideally monthly or every 10 000 km.

A heavy vehicle will lose speed when climbing a steep hill. Changing to a lower gear will help you to maintain an appropriate speed.

Codes are shown on the wall of the tyre. These refer to the maximum load and speed capability of the tyre.

Traffic queues on the motorway are fairly common, often due to the volume of traffic at peak times or to incidents. If you see a queue of stationary traffic ahead, switch on your hazard warning lights for a short while to warn those behind you of a hazard ahead.

As the top deck is longer than the cab and trailer, it will take up more room as the vehicle turns; you must make sure that you've allowed for the wider swing of the deck. Even if your cab is well clear, the overhanging deck could hit obstructions such as telegraph poles or traffic signs as you go round a corner.

The reverse warning bleeper is fitted to your vehicle to warn others near the vehicle that it's reversing. However, it's no substitute for good all-round observation. Get someone to guide you if you can't see clearly where you're reversing.

The longer top deck needs a wider turning circle than the cab below it. To avoid hitting lampposts, telegraph poles, etc, you must allow for this overhang when turning.

Look out for cyclists who don't have lights on. Also be aware that pedestrians - especially those in dark clothing - may be difficult to see.

Engaging the diff-lock means that the driven wheels are locked together. This reduces the likelihood of wheel spin. Remember to switch off the diff-lock as soon as you're on firm ground again, otherwise you could damage the transmission.

Children can be unpredictable, and when they're in groups they may fool around and push each other into the road. You should drive with extreme caution when you're near them. You need to be ready to stop suddenly.

Every year, many people are seriously injured by falling from vehicles. Using suitable steps will lessen the chance of falling. Be aware of the dangers when loading or unloading vehicles.

A SORN allows you to keep a vehicle off the road and untaxed. The SORN remains valid until the vehicle is taxed, sold or scrapped. If you buy a vehicle that has a SORN, the SORN will finish as soon as you buy it. You'll need to make a new SORN if you want to keep the vehicle off the road and untaxed.

You should check your oil level regularly and pay attention to any oil warning devices. A damaged engine can be very expensive to mend. It could also cause sudden and unexpected loss of control, putting you and others in danger. If your engine seizes, you should make every effort to stop in a safe place.

Any medical condition that could affect your ability to drive a lorry or a bus safely may prevent you from holding a licence. These conditions include serious visual impairment, heart disease and some mental disorders. For more information about medical standards, you should contact the Drivers Medical Branch, DVLA, Swansea.

If you have to drive through a flood, do so with caution. Once out of the flood, you need to test your brakes to make sure they're working properly. To do this, check what's behind you, then drive in a low gear with the brakes gently applied.

To achieve maximum stability, the load should be placed to keep the centre of gravity as low as possible. To do this, heavy items should be placed close to the centre line and spread over the full length of the vehicle. Lighter items should be placed along the sides.

Short-wheelbase vehicles will bounce more noticeably than some long-wheelbase vehicles when empty. This can affect braking efficiency and all-round control.

Projection marker boards must be fitted if the load on your vehicle overhangs by more than 2 metres (6 feet 6 inches). This will help other road users who may not notice the projecting load.

Goods vehicles exceeding 2500 kg laden weight must always have their parking lights switched on when they're parked on the road at night. This includes parking in lay-bys: other drivers entering the lay-by must be able to see the vehicle.

When an analogue tachograph is installed and calibrated, an installation plaque is fixed near the tachograph. This shows the date of the most recent tachograph calibration. Under EU rules, this must take place every six years.

When driving large vehicles, windscreen pillars and large mirrors can easily create blind spots as you look left and right at junctions. Altering your body position slightly while looking into the new road can give you an improved view of the traffic. If in doubt, look again and reassess the situation. Don't take chances.

It's illegal to use a hand-held mobile phone while you're driving. Park in a suitable place before receiving or making a call or text.

You should always be aware of the amount of room your trailer needs when it's going around bends and corners. If you need to go onto the other side of the road, make sure there's no oncoming traffic before you move out.

Rope hooks aren't designed to withstand high forces. They're usually just welded or bolted to the underside of the platform. Many are so weak that they can easily be distorted by a ratchet buckle when a webbing strap is tightened. Secure anchorage points should be built into the main frame or chassis of the vehicle.

You must check the nearside mirror during and after overtaking a motorcyclist. Make sure that the rider is still in control and that your vehicle's draught hasn't caused them to lose their balance.

When approaching a tunnel, switch on your dipped headlights. Be aware that your eyes might need to adjust to the sudden darkness. You may need to reduce your speed.

When you're being overtaken, the other driver has to decide when it's safe to complete the manoeuvre. Don't give an unofficial signal, however well intended. There may be a hazard you're unable to see from your position.

Stopping where you see this sign is likely to cause an obstruction, which could lead to traffic delays. Obeying the sign will help keep the traffic flowing.

Don't continue to drive if you feel the onset of tiredness. Find a safe place to stop for a rest. Walking around in the fresh air during your break will help but it's no substitute for adequate rest.

During very cold weather, it's tempting to have the heating in the cab turned on full. Be aware that this may help to make you feel drowsy, especially after you've eaten a meal. Open the window slightly to let in some fresh air until it's safe for you to stop and rest.

Always have wheel nuts checked soon after their initial tightening. They should be tightened to the torque specified by the vehicle manufacturer.

If you're disqualified from driving because you were two-and-a-half times over the legal limit, you'll be classified as a high-risk offender. Before you can regain your licence, you'll have to satisfy the Driver and Vehicle Licensing Agency (DVLA) that you don't have an alcohol problem.

Unless you're on firm, level ground, there's a risk of your lorry overturning when the body is tipped. Before raising the body, check that you're well clear of overhead obstructions such as power lines.

Learning is a process of practice and experience. Try to understand this and tolerate others who are at the beginning of this process.

Continuous high speeds on the motorway can cause the tyres to become hot and to shred. If you notice this happening, you must stop on the hard shoulder as soon as it's safe to do so. It's dangerous to drive a defective vehicle.

Make sure you or someone else has called the emergency services. Check the casualties and, if you feel able to give first aid, do so. Alternatively, ask any bystanders if they can help.

You should make sure that you drain the air tanks daily to avoid moisture in the system. Most modern vehicles have an automatic draining system, which should be checked regularly.

In cold weather, diesel fuel can solidify as it starts to freeze. This is known as waxing. Waxing prevents the fuel from flowing properly and this can stop the engine from running.

Wide loads are a hazard to other road users. In addition to having an attendant with you, you must notify the police if your load is wider than 3.5 metres [11 feet 5 inches]. Side markers must also be used to show other road users the limits of your vehicle.

With a front-tyre blow-out, you won't be able to steer properly. Keep a firm hold of the steering wheel and slow gradually to a stop. Don't brake hard or steer sharply.

If you overfill the engine with oil, you could cause the engine to build up too much pressure when it's running. This could cause damage to oil seals and gaskets.

Both your load and your vehicle can be a target for thieves. Taking simple precautions, such as securing the windows and doors, can deter thieves and help ensure your own safety.

Some foods need to be transported at controlled temperatures. Drivers will need to be trained in the use of refrigeration units and correct hygiene procedures.

Leaving the filler cap off, or not properly securing it, could result in a spillage of diesel onto the road. Because diesel is slippery, this would be a major hazard, so make sure to correctly secure the filler cap after use.

Debris falling from vehicles can be very dangerous to other road users, so skips need to be covered when they're transported. Falling debris may also cause environmental damage.

High-sided vehicles are severely affected by side wind because of the large surface area of the bodywork. The risk of loss of control is increased if the vehicle is unladen.

At a traffic incident, the danger of further collisions and fire needs to be dealt with first. Then you should deal with injuries in this order: airway, breathing, compressions and bleeding. Don't remove a motorcyclist's helmet unless it's essential to do so.

On smart motorways, the hard shoulder can be used as a running lane when a speed limit is shown above it. However, a red cross above the hard shoulder means that this lane shouldn't be used, except for emergencies and breakdowns.

This sign is used to warn of overhead electrified cables and is usually accompanied by a plate indicating the safe height limit.

Look out for restrictions on long vehicles. Length restrictions are found where there isn't much room to turn (for example, in a tunnel) or where there's a risk of grounding.

If your vehicle catches fire in a tunnel, you should first try to drive it out - but only if you can do so safely.

At the scene of an incident, you should tell your passengers what has happened, while reassuring them that they're not in danger. Explain to them that the emergency services are dealing with it and they should remain on the coach.

When deciding which type of restraint to use, consider what may happen if you have to brake sharply. Tubular loads may move forward with some force if you have to brake sharply in an emergency. This could cause serious damage to the vehicle's headboard.

Make allowances for cyclists. Allow them plenty of room, and be aware that they also have to deal with hazards. They might swerve or change direction suddenly to avoid uneven road surfaces.

Brake fade occurs when the brakes overheat. Good forward planning and correct use of the gears when descending hills, together with proper use of the endurance brake (retarder), can help to prevent brake fade.

Extra care is needed when driving in heavy rain. Reduce your speed and switch on dipped headlights. Tyres will have less grip on a wet road and it will take up to twice the distance to stop when compared with good dry conditions.

Tailgating' is the term used when a driver or rider follows the vehicle in front too closely. It's dangerous because it restricts your view of the road ahead and leaves no safety margin if the vehicle in front needs to slow down or stop suddenly. Tailgating is often the underlying cause of rear-end collisions or multiple pile-ups.

Some vehicles are fitted with an audible warning device that sounds when the vehicle is being reversed. As these devices make a loud noise, they shouldn't be used between 11.30 pm and 7.00 am in a built-up area. Audible warning devices are an effective safety feature, but they don't take away the need to use effective observation around the vehicle before and while reversing.

After overtaking, check your nearside mirror carefully before moving back to the left. Don't rely on the other driver flashing their headlights, because only you can make the decision that it's safe.

You should always try to stop, if it's safe, for people waiting at pedestrian crossings. However, avoid waving them to cross. Another driver may not have seen them, may not have seen your signal or may not be able to stop safely.

Endurance brakes or 'retarders' help to control a vehicle's speed. They operate by applying resistance to slow the vehicle without using the wheel brakes, so avoiding brake fade. The methods used include: increased engine braking, exhaust braking and transmission-mounted devices.

Switch your engine off when you're stationary for some time, especially where noise and exhaust fumes may cause annoyance. This can help to protect the environment and save fuel.

You may use the right-hand lane to overtake on a two-lane motorway. Lorries weighing more than 7.5 tonnes, vehicles that are required to be fitted with speed limiters, and vehicles towing trailers aren't allowed to use the right-hand lane of a motorway with three or more lanes, except in special circumstances.

Parking on the yellow zigzag lines will block the view of the school entrance. This will endanger the lives of children wanting to cross the road on their way to and from school.

Large vehicles can be fitted with various types of endurance brake (retarder). Make sure you're familiar with how the system operates on the vehicle you're using. Don't risk a crash or collision through ignorance.

If the steering becomes heavy, the power-assisted steering may have failed. It's also possible that your vehicle has a puncture or the load might have shifted. You should stop safely, investigate the cause and call for help if necessary.

Power-assisted steering operates when the engine is running. If a fault develops, much greater effort is required to turn the steering wheel. Don't attempt to drive a vehicle if you're aware of a fault in the power-steering system.

On a quiet country road, always be aware that there may be a hazard just around the next bend, such as a slow-moving vehicle or pedestrians. There might not be a pavement and people may be walking on your side of the road.

It's essential to know the height of your vehicle before setting off. This should be clearly marked, usually in the cab, and visible from the driving position. Look out for restrictions that you may not have seen on a map - they may be temporary.

The priority when dealing with an unconscious person is to make sure they have a clear airway and can breathe. Stay with the casualty and make sure someone rings for an ambulance.

You should be familiar with all warning lights and buzzers fitted to your vehicle. If you're driving the vehicle for the first time, make sure that you know the function of each. If the brake warning light shows a fault in the system, stop as soon as it's safe to do so. Report the fault, and don't continue until it's been corrected.

The parking brake must always be set whenever you leave the vehicle. It's an offence not to leave your vehicle properly secured.

A sleeper cab can create extra blind spots. Look out for vehicles just to the rear offside and nearside of your cab - they could soon become hidden in your blind spots.

Plan well ahead and take care if you need to move out or straddle lanes due to the length of your vehicle. Other road users may not understand your reasons for doing this and may try to pass on your left. Check your mirrors before and as you turn. It's better to use extra space on the road you're leaving than to find there's not enough room when you turn in.

The flashing amber light allows pedestrians already on the crossing to get to the other side before a green light shows to the traffic. Be aware that some pedestrians, such as elderly people and young children, need longer to cross. Let them do this at their own pace.

Under no circumstances should you attempt to move or drive a vehicle with an air leak in the braking system. Report the fault immediately, or arrange to have it repaired. Place a warning sign in the cab, telling other drivers not to drive the vehicle and why.

When an emergency arises, pull onto the hard shoulder and use the emergency telephone to report your problem. You'll be connected to an operator, who will put you through to a breakdown service. Never cross the carriageway or a slip road to use a telephone.

If a mandatory speed-limit sign is shown above the hard shoulder, this lane can be used as a running lane. You must stay within the signed speed limit. Look out for any vehicles that have broken down and are blocking the hard shoulder.

You must be able to stop safely in the distance that you can see to be clear ahead. This will be the distance illuminated by your headlights or by street lights and will generally be less than you can see in daylight.

Your vehicle will make more noise than a car, so you should try to avoid making unnecessary noise at any time of the day or night. This is especially important when you're in a residential area at a time when people are likely to be sleeping.

At the scene of an incident, first make sure there's no danger of further collisions or fire before dealing with any casualties. The priority when dealing with an unconscious person is to make sure they can breathe. This may involve clearing their airway if they're having difficulty or there's an obvious obstruction. Don't remove a motorcyclist's helmet unless it's essential, as you could cause them serious injury.

Plan your overtaking carefully. The weight of your vehicle, combined with the restrictions imposed by a speed limiter, is likely to make your vehicle lose speed on uphill gradients. You should take this into consideration before attempting to overtake another moving vehicle.

You must be aware of the position of other road users, so that you know how they may be affected by your actions. Before opening your door, it's important to check the mirrors, as well as looking around for passing or approaching vehicles and pedestrians.