What's with the purge siren in the Model Apartment?

[Charlotte]

I went trough the DLC missions fairly quickly, without paying too much attention. Now that I've bought the house and am in the process of remodelling the place, I notice this weird siren going off in the background every so many minutes. It's part of the ambience sound and it's freaking me the hell out. It sounds like a T-Rex honking in the distance. Is there an air raid coming? In that case, I won't bother doing up the place. ¯\_(ツ)_/¯

[Nite69]

its just standard CITY sounds you are working on an apartment block in that house so yea its part of the ambient noise