So you don't think unified wiring colours throughout the EU a good idea?
But if you did how then do you get round the fact the that Germany apparently thought red the best colour for a safety wire while the UK chose green? Red may mean danger in most countries, but then the 'dangerous' wire to get wrong on a three wire appliance is the earth - not the other two. And don't let's forget red is the least visible colour to man in general - and even more so if you're partially colour blind. So it wasn't chosen with science but merely became the convention - why, I don't know. And I'd guess the same with threads and clocks.
Strange, given the main idea of the original 'common market' was to prevent wars between the likely members which had occurred rather too frequently in the past.