DOB Findings and Recommendations for WTC, Feb 2003

NYC 9/11 Public Portal Document

(al Elevators in buildings classified in "Occupancy Group E" (Office Buildings')-where elevators serve more than three (31 floors and in existing office buildings where a new shaft is constructed to contain two (21 or more elevators shall meet the following requirements: (11 At every floor above the main entrance floor where the fire command station is located, all elevators shall open into an enclosed elevator vestibule. The elevator vestibule shall be separated from the building occupancy by smoke barriers extending from floor slab to floor slab and where there are openings, the doors shall be self-closing or automatic closing upon smoke detection. (21 Access to an exit on any floor through the enclosed elevator vestibule shall be permitted if the occupied areas on that floor have access to at least one other required exit that does not require passing through the elevator vestibule. (31 In buildings with a small footprint, the commissioner may accept alternate means or an exemption from the requirements (il and (iil listed above, and from the smoke damper requirements contained in the applicable definitions in section 27-232.

Paragraph (c) of section 27-371 of article 5 of subchapter 6 means of egress of chapter one of title twenty-seven of the administrative code is amended to read as follows; §27-371 Doors. (c) Smoke Stop Doors, - Smoke stop doors shall be ... unless the doors are also used as horizontal exits in which case they shall comply with the provisions of section 27-373 of this article. Smoke stop doors may be constructed of tempered glazing or the equivalent and be protected by sprinkler heads constructed in accordance with subchapter 17 of this chapter and installed a maximum of 6'-Q" (1.830 m) on centers on each side of the opening. Smoke stop doors may be double-acting but shall close the opening completely with only such clearance as is reasonably necessary for proper operation. Smoke stop doors shall normally be in the closed position, except that they may be left open if they are arranged to close automatically by an approved device which is actuated by an interior fire alarm system meeting the requirements of subchapter seventeen of this chapter [.] or upon smoke detection. Tempered glass smoke stop doors shall be marked in accordance with the Rules of the Board of Standards and Appeals.

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Page 46 WTC Building Code Task Force February 2003 Findings and Recommendations

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