One of the first things we did in an electric car was narrowly miss driving into a pedestrian who stepped out into the road. That was with the Nissan Leaf in 2012 and this was around the same time that legislators started talking about the potential for accidents from silent electric vehicles.
1 July 2019 marks the date that the EU ruling on acoustic vehicle altering systems (AVAS) comes into effect. It's actually called "Quiet Road Transport Vehicles (QRTV) with regard to their Reduced Audibility" and it outlines that all new models from this date need to be equipped with a system to make noise at low speeds.
The real aim is to protect pedestrians, because at low speeds an electric car makes very little noise - some tyre crunch that you might miss amongst the background noise of a road. As an electric car gets faster, it starts to make more noise, from the tyres and motors, but you don't get the same persistent burble that you do from an internal combustion engine.
The new ruling will cover all types of electric or hybrid vehicle that can move in forward or reverse gears without the engine running - so that's pure electric, hybrid, hydrogen and hydrogen hybrid vehicles.
The ruling allows the manufacturer to make the sound driver selectable - so you might be able to choose the exact sound emitted - and you're also able to turn the sound off. Why might you want to turn it off? If you're leaving for work at 2am, you don't want to be reversing out of your drive making noise - so you still get that stealthy option to keep the neighbours happy.
The noise will be emitted at speeds below 12mph (19kph), so it's the sort of thing that will stop people walking out in front of your car when you're trying to park and things like that.
The ruling initially applies to new models, but from 2021, it will apply to all new cars. What that means is that if you go any buy the new Mini Electric - expected to be released later in 2019 - it will have to make the noise, whereas models already available won't have to until 2021.
Some cars already have it: BMW added the option in 2014 on the i3 and the i8. BMW have also said they are working with Hans Zimmer on the soundtrack for future electric vehicles.