[Drammach]

is if life is in iminent danger, like a hostage situation.

I would add:
In pursuit of a fleeing felon..
As I recall it, ( as taught ) if an officer is in the act of pursuit of a "suspect" that has committed a felony, and that fleeing felon enters a domicile or building, the officer is considered in "hot pursuit" and can follow without stopping to obtain a warrant..

[eastforker]

Certainly!

[texasflower]

This post backs up what I was telling you.