two exits in one exit stair shaft

[sunyaer]

The following is from the commentary on part 3 of NBC 1985 from this link: https://nrc-publications.canada.ca/eng/view/ft/?id=fe9acadd-3a5a-48e8-8771-926ce1fc83fe

In the 3rd sketch of the screenshot below, it looks the two exits are going to the same exit shaft, how can two exits be placed in one exit stair shaft?

 

[tmurray]

Well... there is a reason it is not in the code anymore...

You would have to completely separate them with a fire separation for them to be considered two distinct exits. If they are not separated from one another, all you have is two entrances into the same exit.

 

[Inspector Gadget]

And in addition, if it's a part 3 building, the discharges would have to be 9m (IIRC) from each other at the exterior ....