If you mean broken sirens, there are quite a lot here in the UK. Not many of them ever sound, though. Right you are, and for some inexplicable reason, the majority of those that don't work properly over here that are tested happen to be Secomak GP12s. Secomak CS8s are also dodgy, but on average are...

Update on a London siren. The whatever it is on the roof of Vanguard Self Storage is still there as of May 2022. The Hawker Hunter jet fighter that was on the roof was moved inside after being taken down, and I wanted to see if the siren was still up. To my surprise, it is! See the upper right sect...

Just remembered I have this account, so I've got some things to add... At least two electronic sirens at BOC Gases in Immingham - think they are Klaxon ES but can't be sure, I don't know enough about these electronic things... 53.606310, -0.158250 - six-horned bi-directional. Not visible on Street V...