UK Emergency vehicle sirens

So today I was driving to work when a police car went onto the wrong side (right side) of the road at a traffic lights and turned on it’s siren, nothing especially strange about that you might say.

But what makes it weird enough for me to ask in GQ, is that when he hit the blues and twos, I heard the “Nee-Naw Nee-Naw” siren of my childhood (late 70s - 80s) not the usual “Woo-woo-woo” (which is one of the newer, more transatlantic siren sounds) that the Met have been using for years now. Now this was a new police car, not an old Rover 2000 high speed pursuit car or anything.

My question is two part:

  1. Why did they get rid of (or stop using) the “nee-naw nee-naw”?

  2. How come they have different sirens available in their vehicles, do they mean different things?

Thanks.

Can’t give an explanation (sorry), but I wish they’d bring back the old nee-naw. I find I can’t hear the newer sirens until they’re almost on top of me.

Perhaps drivers get complacent and tune-out the siren they are used to. Reverting to an unfamiliar siren would make them take notice.

Infringment on the copyright of Over The Rainbow.