Need Draft Curtain & Closely Spaced Sprinklers?

We're working on a townhouse renovation project in New York City to design sprinklers that conform to NFPA 13.

The building is 4 stories (cellar, basement, 1st-3rd floor, and penthouse) tall. However, the NYC building code enforces NFPA 13 for vertical openings in this case. The building includes a rectangular light shaft going up an enclosed stairway spiraling up from the 2nd - 3rd floors and up through to the penthouse. On the first floor, the shaft starts on a flat ceiling and opens to the rest of the stair hallway and has stairs on one side but does not enclose the shaft on all sides.

Does the shaft on the first-floor ceiling need to have draft curtains and close-spaced sprinklers on the 3 sides that open into the rest of the space?

Please see the picture below of the first floor with the light shaft indicated.

Let me know if you have any questions or require additional information.

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