Question Large Equipment by definition of the NEC. Two Exit ways required UNLESS meets Exceptions (a) & (b). Calls for Doorways. 24 inches wide ,6ft 1/2 High. One end door / other end Ladder industrial fixed. Ladder up or down three steps or more. I have my option I'd like yours. Yoopersup
I wouldn't like to have to scurry down a ladder if there was a problem...especially if I was injured. If there were a door that led to the safety of a landing or platform before I had to climb the ladder I might feel better about it.
The Question comes down to: the one door is per Code & layout calls for two doors. There:s a Door per Code at one end. A Ladder as described at the other end. Does the Ladder as stated comply with code requirement. Exceptions here are not in play! Yoopersup
When I think about "large equipment" I think >600v and that kicks you over to part III. It still lets a permanent ladder be "access"
Access. Permanent ladders or stairways shall be provided to give safe access to the working space around electrical equipment installed on platforms, balconies, or mezzanine floors or in attic or roof rooms or spaces.
Greg 110.33(B) is in part 3 is in the over 600 volt section. This room has several 1200 amp large 480 volt Mcc;s as well as panels. 110.27 (A) 3 in the 600 v & under section has something similar BUT I don't think it's an Exception to the Door at each end section. If it was then you could have a Ladder at each end and defeat the Purpose & reason for a door with push to release hardware to exit the room if burned or injured.
I understand that is over 600v but I would expect that to be more strict. I think you are going to have a hard time finding language that prevents a permanent ladder being part of the egress route from a switch room.