But more on-topic, yes, that is a very impressive emergency door.
I also find this one interesting because it is a rectangular emergency door. Because they are rarely used, it seems to me they are often round even if the corresponding main door is rectangular and I presume this is because round doors would be easier to make. But other rectangular emergency doors exist. This might have been aesthetics conquering economy and/or a question of how the manufacturing plant was set up and which big tools were available.
A longer discussion of emergency doors is at http://www.antique-locks.com/showthread.php/1884-Emergency-Doors.
