You have stopped on the motorway hard shoulder due to a mechanical problem. You are waiting for roadside assistance and your vehicle is safely parked off the live carriageway. What should you do about your engine while you wait?

Explanation

The Highway Code, Rule 123, states that you MUST NOT leave a parked vehicle unattended with the engine running or leave a vehicle engine running unnecessarily while it is stationary on a public road. If your vehicle is stationary and likely to remain so for more than a couple of minutes, you should switch off the engine and apply the parking brake to reduce emissions and noise pollution. On the motorway hard shoulder, once you are safely stopped and not in traffic, you should turn off the engine rather than leave it idling.