Why do lights blink on buildings?

I have noticed both, red lights and white lights on buildings. I always assumed it had something to do with guiding planes that there are buildings here but the other day I realised the even on middle floors white light blinks. But then I noticed that the floors on which this white light blinks are actually refuge areas. So I assume it has got something to do with guiding firefighters in case of emergencies.

But curious to know the actual reason and what’s the regulatory requirement behind this. And if this is just a local requirement or a global practice?