The Siren Board

I thought it was a fluke, but now I heard a siren 2 times/2 different days emitting from the north end of the Chrysler Sterling Stamping Plant.
It sounds like a Model A. It's not steady or wailing, but like someone is using a momentary button.
It could be for an overhead crane in motion or end of shift.
I don't have any video or audio yet.
I'll have to wait over there at the time I heard it and see if I get it again.

Here's a streetview of where the sound is coming from.

http://maps.google.com/maps?q=35777+van ... 81.54,,0,0

I live right near a Ford plant, and it seems to have its own small siren, presumably a Model A as well, though I'm not sure whether the one I'm hearing is just for shifts.

I spend a lot of time inside Ford plants and other facilities, and I've seen Model As and Model Ls around there. I assume they're for evacuation purposes.