LGV Theory Test 10

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.

A significant number of sleep-related vehicle incidents involve commercial vehicles. There's a particular risk when driving between 2.00 am and 7.00 am, because this is when the body clock craves sleep. It's important to take proper rest before, during and between driving duties.

Make certain that your filler caps are properly closed, so that you don't spill fuel as you drive along the road.

You must always disengage the diff-lock as soon as the vehicle is moving. The differential allows the rear wheels to revolve at different speeds, and this allows the vehicle to follow a curved path. Attempting to turn with the diff-lock engaged could result in the vehicle continuing straight on.

When a tyre explodes, fragments are thrown over a wide area. This can create a serious hazard for other drivers. You should regularly check your tyres for cuts, damage and pressure. Frequent checks and proper maintenance can help prevent a blow-out.

There's no way of knowing how deep the snow could be ahead. If you overtake and then become stuck in the snow, you may cause problems for the snow plough, particularly if you block the road.

The differential allows the drive wheels to rotate at different speeds; this is necessary for the vehicle to negotiate corners and bends. On a slippery surface, however, it can cause problems: if one wheel has less traction, it can spin, resulting in a complete loss of drive. The 'diff-lock' prevents the wheels from turning independently and so helps to stop this happening.

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.

If diesel fuel becomes very cold, it can partially solidify. Additives are used by the fuel companies to try to prevent this. Any solidifying (waxing) of the fuel can prevent it from flowing properly and cause the engine to run erratically or even stop.

The only time you may use hazard warning lights while driving is when you're on an unrestricted dual carriageway or motorway and you want to warn other drivers of a hazard or obstruction ahead. Only use them for long enough to make sure your warning is seen.

No motor vehicles are allowed past this sign. Although a motorcycle and car are shown, the restriction applies to all motor vehicles.

DVSA and the police carry out frequent roadside checks of commercial vehicles. Where serious defects are found, the vehicle is taken out of use until they're put right. Details of the prohibition are shared with the traffic commissioner.

The spray-suppression equipment helps to prevent water from being thrown up and causing reduced visibility, for you and other drivers. Driving at a reduced speed in wet conditions will also help to reduce the amount of water thrown up by your vehicle's tyres.

Some weight restrictions apply to heavy goods vehicles only and not to passenger-carrying vehicles. Look for a plate beneath a restriction sign that indicates this. Road signs show weight restrictions in various ways. You should make yourself familiar with all of them, so that you're in no doubt about their meaning and relevance.

Faulty power steering will make your steering wheel very difficult or almost impossible to turn. Continuing to drive could cause danger to you and other road users. You should park safely and get help.

It's important to use a low gear and keep the engine speed high to prevent water from entering the engine through the exhaust system. In these circumstances, it may be necessary to slip the clutch to keep the road speed as low as possible.

Lack of oil could cause the engine to seize, and this could cause sudden and unexpected loss of control. You could break down in a dangerous position and put yourself and other road users at risk.

As soon as you detect a fault on your vehicle, you must take action. Where faulty brakes are concerned, you need to seek help immediately. Always report minor faults as soon as you detect them. Minor faults can become major ones if they aren't repaired quickly.

Always make sure your vehicle is secure and level before a wheel is changed. Apply the parking brake and use chocks if they're available. When the replacement wheel is fitted, all wheel nuts/studs should be retightened to the correct torque. On a motorway, never attempt to change a wheel yourself. Use the emergency telephones to call for assistance.

Alcohol can increase confidence to a point where a driver's behaviour might become 'out of character': someone who normally behaves sensibly suddenly takes risks and enjoys it. Never let yourself or your friends get into this situation.

If you try to overtake another vehicle and realise that you're unable to complete the manoeuvre, ease off the accelerator and drop back behind the vehicle. If the vehicle you're trying to overtake is large, then it will take a long time to pass. You should assess whether you have the time and power to complete the manoeuvre before you try to overtake.

Make sure the locking mechanism is secure by selecting a low gear and attempting to move forward. Apply the parking brake again before leaving the cab. Connect the 'dog clip' to secure the kingpin release handle.

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

In very cold weather, moisture in the storage tanks can freeze. Ice can form in the pipes and this will result in loss of pressure, which could cause brake failure. Make sure that you drain the tanks daily as part of a routine. Most modern vehicles are fitted with automatic bleed valves. Check that they're working properly and that air-drying systems are effective.

Allow horse riders to enter and exit the roundabout in their own time. Don't drive up close behind or alongside them; this could disturb the horse.

You must obey these signs even if there appear to be no problems ahead.

Always plan ahead and take note of gradient warning signs. On downhill gradients, you can help control your vehicle's speed and avoid brake fade by selecting a lower gear in good time.

The faster the traffic is moving, the greater the distance that needs to be kept between vehicles to maintain safety margins. If you find another vehicle driving too close behind you, gradually reduce your speed to increase your distance from the vehicle in front. You'll then be able to brake more gently when you need to, reducing the likelihood of the lorry behind running into the back of your vehicle.

Blind spots can occur when bodywork - such as a door or window pillar - restricts your view. Different types of vehicle have different blind spots.

The operator of a UK-registered vehicle engaged in the carriage of dangerous goods should make sure that the driver has a valid vocational training certificate. These certificates are valid for five years.

When seat belts are fitted to your vehicle, they must be worn unless you hold a valid medical exemption certificate. People making deliveries or collections in goods vehicles are also exempt, when they're travelling less than 50 metres (162 feet).

Vehicles over the weight shown on the sign may not use the bridge ahead. You must know the weight of your vehicle, including any load. With this knowledge you should plan your route in advance, so that you don't come to a bridge you can't cross. That way, you'll avoid delays and save time and fuel.

The horn shouldn't be used between 11.30 pm and 7.00 am in a built-up area. The only exception is when another road user is unaware of you and poses a danger.

Scan the road as you drive. Try to anticipate hazards by being aware of the places where they're likely to occur; for example, pedestrians and cyclists emerging between parked cars on a busy street. If you're prepared, you'll be able to slow down or stop in good time.

Never drive after taking drugs you don't know about. They might affect your judgement and perception - and, therefore, endanger lives.

A bus equipped with a speed limiter must also be fitted with a plate showing the speed setting. This must be fitted in an obvious position, where it can be clearly seen.

On multi-axled vehicles, the inside wheels on the rear twin-axle are the most difficult to check for punctures and damage. A deflated tyre will transfer the weight to the second tyre of the twin-axle pair. This will overload it and could cause it to burst.

When you have to slow down or stop, you should always avoid harsh, late braking. This is particularly important on icy or slippery roads, where you need to brake gently and in good time to make sure you keep control of your vehicle.

Block' gear changing means changing up or down to the most appropriate gear without going through each gear in turn. It reduces the number of gear changes, and this can improve fuel consumption.

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 a pelican crossing, the green light means you may go, but you must give way to anyone still crossing. If someone hasn't finished crossing, be patient. People with mobility difficulties can struggle to cross in the time allowed by the lights.

The view you get in your mirrors may vary, depending on the size of the trailer and the load it carries. Always adjust your mirrors to ensure that you have the best possible view down each side of the trailer before you drive away.

If a build-up of water prevents the tyres from gripping the road, the steering can become unresponsive. If this happens, ease off the accelerator and slow down gradually.

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.

Fast-moving traffic is passing close by, so wait for the breakdown services to arrive. Their vehicle will provide protection while your vehicle is repaired or recovered.

Horses are easily frightened, so pass them slowly and carefully, giving them as much room as possible. On country roads, expect farm animals, horses, pedestrians and farm vehicles. Always be prepared to slow down or stop.

Fluids carried in tankers can move in waves as the vehicle's speed or direction changes. This happens particularly when you brake and then ease off the pedal; the moving wave of liquid causes the vehicle to surge forward. Baffle plates are designed to reduce this surging effect.

The road ahead is at risk from falling rocks and you may also come across fallen rocks in the road

Load security is extremely important. Make sure you park legally and, preferably, in a well-lit area. Some lorry parks are patrolled regularly by the police or security services.

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.

Correctly adjusted air deflectors will save fuel. They should be adjusted to guide the airflow over the highest point at the front of the trailer or load and body.

When a warning light or device indicating a loss of brake pressure comes on, you must stop safely and get the fault put right immediately. The safety of you, your load, your passengers and all other road users is at risk.

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

Drivers' hours and rest periods are controlled in the interests of road safety. A driver's daily rest period should normally be 11 hours, but this may be reduced to 9 hours up to three times between weekly rest periods. It's a serious offence to break these rules and anyone doing so is liable to a heavy fine and even imprisonment.

If you're driving an articulated vehicle or a trailer combination, it's vital that you understand the rules that apply to coupling and uncoupling the brake lines. If you take a practical driving test with a trailer, you'll be expected to demonstrate this during the test. The lines are colour-coded: red is the emergency line, blue is the auxiliary line and yellow is the service line. They must be connected strictly in accordance with the correct procedure.

The pump creates a vacuum in the servo unit. This reduces the amount of pressure you need to apply to the brake pedal. Without this vacuum, it's extremely difficult to press the brake pedal down.

Continually using the brakes could cause them to overheat. When that happens, they become less effective. This is called brake fade, and it occurs most often when the driver has to control the vehicle's speed on a long downhill gradient. To help prevent brake fade, use the endurance brake (retarder) and a lower gear to keep the vehicle's speed in check, rather than the wheel-mounted brakes.

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.

Passing the moped and then turning into the junction could mean that you cut across in front of the rider. This might cause them to slow down, stop or even lose control.

If you're travelling on a motorway and your view ahead is poor, then you should reduce your speed. Leave at least four seconds between your vehicle and the one in front, and make sure that others can see you by using your dipped headlights.

On a motorway where there's a long uphill gradient, there may be a crawler lane. This helps the traffic to flow by making an extra lane available on the left for slower, heavy vehicles.

Staying well behind the vehicle in front will improve your view of the road ahead. This will give you more time and room to react to hazards. Use the two-second rule to make sure you're not too close. Don't move out to the right, as this could put you into the path of an oncoming vehicle or obstruct smaller vehicles that wish to overtake.

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.

Try to anticipate the actions of other road users. When you're waiting at a junction, don't emerge until you're sure of their intentions; their signals might be misleading.

When getting out of your lorry cab, it's essential that you check it's safe to dismount by checking your mirrors and looking out for traffic. When you're safely down, it's then a good idea to walk round and check your tyres, load, lights, brake lines, electrical connections, etc.

Puffin crossings have sensors that detect when pedestrians are using the crossing. The sensors control the timing of the traffic lights, and this means that there's no flashing amber phase as there is with a pelican crossing.

Always plan well ahead before overtaking. Take into consideration the size of your vehicle and whether there's a gradient ahead. The load on your vehicle will slow you down on an uphill gradient. It may be better to wait until you're on the level before trying to overtake.

The horn shouldn't be used between 11.30 pm and 7.00 am in a built-up area. The only exception is when another road user is unaware of you and poses a danger.

Take care to secure caps and tank hatches. Diesel is very slippery and, if spilled on the road, it's particularly dangerous to motorcyclists.

You can legally remove your seat belt when carrying out a manoeuvre that involves reversing. Don't forget to put it back on again when you've finished.

It's not always possible for drivers in the left-hand lane to change lanes to let joining traffic merge. However, you should be ready to adjust your speed to help the joining driver merge safely.

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.

Local-authority environmental health departments check vehicles' exhaust emissions. They have the power to prosecute the driver and the operator, as do enforcement bodies such as DVSA.

A loose brake pedal would suggest a serious loss of fluid from the hydraulic system. Don't drive your vehicle until the fault has been checked and fixed by a qualified person.

Roadworks can involve complex lane layouts. Reflective green-and-yellow fluorescent studs are used to separate the lanes in a contraflow traffic system. As you approach roadworks, look for traffic signs giving you advance information, which may relate to the size or type of vehicle you're driving.

It's illegal to use a hand-held phone while driving. When you've stopped in a safe place, you can concentrate on your call or message. Using a phone while driving means you won't have full control of your vehicle. This could result in a collision, with serious or even fatal consequences.

When you're driving on a smart motorway, speed limits will show above each lane. These limits are shown inside a red circle and must be obeyed. A red cross will usually appear above the hard shoulder. When the hard shoulder is being used as a running lane, an appropriate speed limit will be displayed instead.

The formula used to calculate the payload of a vehicle is the maximum authorised mass (MAM) minus the tare weight. The tare weight is the total weight of the vehicle, including the crew and extra equipment.

It's important that you always select a place to park that's both safe and legal. Don't park on or too close to a pedestrian crossing or a school entrance; this would restrict the view for drivers and pedestrians. Don't park at a bus stop either, because buses would then have to stop in the road, creating a hazard for other traffic and for passengers getting on or off the bus.

If you're driving under EU rules, you mustn't drive continuously for more than four-and-a-half hours without taking a break. If you've driven continuously for four-and-a-half hours, you must take a break of at least 45 minutes. Include your stops in the timetable when planning your journey.

Plan well ahead before overtaking. Be aware that a speed limiter may cause you difficulties when overtaking another vehicle, particularly when climbing a hill.

Before driving into a tunnel, you should take off your sunglasses. If you don't, you'll find that your vision is restricted - even in a tunnel that appears to be well lit.

Always be aware of your limited vision around your vehicle, due to its size and shape. Never move off without checking along the nearside of your vehicle. You should be aware of the possibility of cyclists and motorcyclists getting trapped between your vehicle and the kerb.

Modern tankers are fitted with baffle plates inside the tank compartment. These help to minimise the movement of liquids and, therefore, reduce the 'wave effect'.

Always maintain a safe following distance from the vehicle in front. If another vehicle pulls into the gap, slow down to re-establish a safe following distance. Following too close is dangerous and places you and other road users in unnecessary danger; your view of the road ahead will be seriously reduced, and you won't be able to see or plan effectively.

Plan ahead and use your endurance brake (retarder) to help keep your speed in check on long downhill gradients. This can help to prevent your brakes from overheating and fading.

Being seated properly is very important when driving long distances. A poor driving position can quickly cause fatigue. You should make sure that you can reach all the controls comfortably.

Sulphur produces acidic gases. Diesel fuels with lower sulphur content have been produced to reduce exhaust emissions that harm both people and the environment.

Vehicles such as motorcycles, bicycles and caravans could be blown off course by strong winds. You should be aware that your vehicle could cause additional buffeting when you overtake, so allow them plenty of room.

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.

Cycling in today's heavy traffic can be hazardous. Some cyclists might not feel happy about crossing the path of traffic to take up a position in an outside lane. Be aware of this and understand that, although they're in the left-hand lane, the cyclist might be turning right.

Jack-knifing occurs when the tractor unit is pushed by the semi-trailer pivoting around the coupling (fifth wheel). This is more likely to occur with an unladen vehicle.

As you pass pedestrians or vehicles on your left, you should use your nearside mirror and check that you've passed them safely. You need to allow a good safety margin before you move back to the left.