I was in a ten storey commercial building with an adjoining parking structure just two days ago when a fire alarm went off.  I happened to be in an office on the eighth floor at the end of a corridor and the audible alarm was pretty muted.  Someone listening to music through earbuds could easily have overlooked it.  And no, there were no flashing lights or strobes to alert the hearing impaired either. 

Sometimes, sad to say, fickle lady luck may abandon you without notice.  And luck has always had a lot to do with living or dying.