Most would probably have no idea what they were doing wrong, the children’s health they were threatening, the damage to the planet they were causing, the money they were wasting – all needlessly.
I make no apology in returning to this topic – if you haven’t guessed it already – because it is ruining my, and I daresay many others’, daily walks through otherwise pleasant streets in an effort to stay sane as the Covid pandemic stretches on.
My previous description of these miscreants was getaway drivers, keeping their engines running because they needed to make a fast exit.
Back in the day, such criminals would not have raised suspicion, but idling is nowadays illegal in many areas for altogether different reasons, and we should have every reason for asking motorists why they are still doing it.
I don’t want my attempts to stay healthy by going for a walk marred by having to pass vehicles belching fumes simply because the driver has forgotten or can’t be bothered to switch off their engine.
A key argument must be that, with climate change top of the world’s agenda but still somewhat nebulous in terms of what individuals can actually do about it, simple changes to our behaviour like this one will count.
You might think modern engines are far cleaner than their predecessors and emit few harmful emissions.
However, the respected former government Transport Research Laboratory, now TRL, has calculated that serial abusers, sitting outside a primary school for five minutes, morning and evening, could, over a year, push the area’s pollution levels over legal limits.
And this is not just carbon dioxide, but nasties like nitrogen oxide and particulates, which have been linked to bronchitis, cancers, heart disease and asthma.
What you might not know is they seep into vehicles too – so drivers are also poisoning themselves.
TRL has also scotched the myth that re-starting the engine uses more fuel than leaving it running, when the opposite is true.
Visualising the problem is a compelling way to get the message across, and TRL has lent its support to an innovative campaign launched in London in an attempt to get motorists to think about the consequences of their actions.
The Engine Off, Every Stop initiative started by the City of London Corporation and Camden Council imaginatively depicts the gases coming out of an exhaust pipe from a car parked outside a school as a huge plastic bubble expanding to dwarf the vehicle.
Slogans on the bubble read: “An idling engine can produce this much pollution in one minute” and “Would you idle your engine knowing it can stunt young lungs?”
TRL wants to see the Vehicle Idling Action campaign, which has been extended across London, spread to the rest of the UK, noting that Edinburgh is among other cities “suffering from major sitting traffic issues”.
In the advert, the driver notices the growing bubble in his rear view mirror, switches off the engine and it disappears back up the exhaust pipe. Neat.
If only other motorists could see so vividly the harm they are causing.