To supersede the requirements stated in Sentence 9.9.4.2.(1), which would otherwise require the stairway to be separated from floor areas, and in Sentence 9.10.1.3.(6), which would otherwise require an unenclosed stairway to conform to Subsection 3.2.8. for the protection of openings through floor assemblies, if certain conditions are met.
This is to limit the probability of delays in the evacuation or movement of persons to a safe place, which could lead to harm to persons.