Environmental issues: bus & PCV theory test questions

1. Keep the engine running to keep the air pressure up
2. Rev the engine to keep it warm
3. Apply the parking brake and switch off the engine ✓
4. Leave it idling with the lights on

Answer: Apply the parking brake and switch off the engine. Switching off when stationary for more than a couple of minutes cuts emissions and noise. You can keep it running in stationary traffic or to diagnose faults.

The Highway Code: rule 123

1. To clean the fuel injectors
2. To reduce harmful nitrogen oxide emissions ✓
3. To stop the fuel freezing
4. To cool the engine

Answer: To reduce harmful nitrogen oxide emissions. AdBlue is injected into the exhaust system to convert harmful nitrogen oxides into nitrogen and water. Keep it topped up.

Vehicle handbook and operator guidance

1. Traps soot particles from the exhaust ✓
2. Filters the air entering the cab
3. Cleans the fuel before it reaches the engine
4. Reduces engine noise

Answer: Traps soot particles from the exhaust. A DPF traps soot from the exhaust. It needs to regenerate regularly, so follow the warning lights and handbook advice.

Vehicle handbook and operator guidance

1. Changing up through every gear in order
2. Holding the clutch down between gears
3. Changing gear without the clutch
4. Missing out intermediate gears when it's appropriate ✓

Answer: Missing out intermediate gears when it's appropriate. Block changing means skipping gears that aren't needed. It saves fuel and reduces wear.

Vehicle handbook and operator guidance

1. In the red band
2. As low as possible, even if the engine labours
3. In the green band ✓
4. As high as possible before changing up

Answer: In the green band. The green band shows where the engine works most efficiently. Changing gear within it saves fuel.

Vehicle handbook and operator guidance

1. It lets you drive in a lower gear
2. You brake and accelerate less, so you use less fuel ✓
3. It allows you to keep the engine at high revs
4. It means you can ignore speed limits

Answer: You brake and accelerate less, so you use less fuel. Planning ahead lets you keep moving smoothly, reducing harsh braking and acceleration. That cuts fuel use and emissions.

The Highway Code: rule 146

1. They increase fuel use and affect braking and steering ✓
2. They reduce fuel use
3. They make the ride smoother and safer
4. They have no effect on a large vehicle

Answer: They increase fuel use and affect braking and steering. Under-inflated tyres increase rolling resistance and fuel use. Your brakes and steering will also be affected.

The Highway Code: Annex 6

1. To let a customer know you've arrived
2. To greet another driver
3. Whenever you need to
4. Only if another road user poses a danger ✓

Answer: Only if another road user poses a danger. You must not use your horn while stationary, or in a built-up area between 11.30 pm and 7.00 am, except when another road user poses a danger.

The Highway Code: rule 112

1. So the engine starts more easily
2. So the fuel gauge reads correctly
3. Spilt diesel pollutes and makes the road very slippery ✓
4. So the tachograph records the refuel

Answer: Spilt diesel pollutes and makes the road very slippery. Diesel spills are dangerous, especially to motorcyclists, and harm the environment. Make sure the cap and seal are secure and don't overfill.

The Highway Code: Annex 6

1. Revving the engine before switching off
2. Keeping the vehicle well serviced ✓
3. Driving in a lower gear than necessary
4. Planning your route to avoid congestion ✓

Answer: Keeping the vehicle well serviced; Planning your route to avoid congestion. A well-maintained engine and avoiding congestion both reduce emissions. Revving and using low gears unnecessarily waste fuel.

The Highway Code: Annex 6

1. They must not exceed the prescribed levels ✓
2. They only matter on motorways
3. They're only checked when the vehicle is new
4. They don't apply to diesel engines

Answer: They must not exceed the prescribed levels. Exhaust emissions must not exceed prescribed levels. Faults that cause excess smoke should be fixed quickly.

The Highway Code: Annex 6

1. By using the right-hand lane of motorways
2. By driving faster than other traffic
3. By running empty when it's quiet
4. By carrying many people who might otherwise use cars ✓

Answer: By carrying many people who might otherwise use cars. One bus can replace many cars, which cuts congestion and emissions per passenger.

The Highway Code: rule 223

1. Leave the engine running to keep the bus warm
2. Rev the engine every few minutes
3. Switch off the engine ✓
4. Run the engine to charge passengers' phones

Answer: Switch off the engine. If you're stationary for more than a couple of minutes, switch off the engine to reduce emissions and noise.

The Highway Code: rule 123

1. It makes the journey longer
2. It saves fuel and gives a more comfortable ride ✓
3. It increases brake wear
4. It means you can skip stops

Answer: It saves fuel and gives a more comfortable ride. Smooth acceleration and early braking use less fuel and keep passengers steady.

The Highway Code: rule 117

1. Pedestrians may not hear you approaching ✓
2. You won't need to check your mirrors
3. It can't be driven in the rain
4. It's not affected by speed limits

Answer: Pedestrians may not hear you approaching. Electric vehicles are quiet, so pedestrians may not hear you coming. Take extra care near bus stops and crossings.

The Highway Code: rule 224