Ok guys,
Here is my understanding. As long as we have already provided minimum and appropriate number exit stairs, other stairs may be for convenience use and not required to meet exit stair requirements. The stair in my project serves a stepped seating area (not fixed) that is an assembly area spanning two floors. The building is fully sprinklered.
The confusing way the code is written designers sometimes think that if a stairway is not required as a Means of Egress it doesn't need to comply with Chapter 10 which is not true but sounds like it because of:
1001.1 General. Buildings or portions thereof shall be provided
with a means of egress system as required by this
chapter. The provisions of this chapter shall control the
design, construction and arrangement of means of egress
components required to provide an approved means of egress
from structures and portions thereof.
MEANS OF EGRESS. A continuous and unobstructed path
of vertical and horizontal egress travel from any occupied
portion of a building or structure to a public way. A means of
egress consists of three separate and distinct parts: the exit
access, the exit and the exit discharge.