Okay, first how do you abandon ship? The first floor may be underwater, so therefore are the fire escape doors. The roof is still far to far to jump to anywhere safe from. Do you smash a window on the first floor and risk sparks in a gas leak? If so how do you even go about breaking modern safety glass? What if the fire is on the nearest level to the water (second floor for Americans, first for Europeans), do you risk the jump into moving debris laden water?

You've gotten out of the building and are now in the cacky, where do you go? Other offices maybe inaccessible for the same reasons you had trouble getting out of the building. How do you survive a swim in probably fast moving, relatively deep water with debris floating in it?