NYC Admin. Code § 27-521.1 Applicability.
§ 27-521.1 Applicability.
This article shall apply to the construction, alteration and use of atriums.
Atriums
NYC Admin. Code tit. 27, ch. 1, subch. 7, art. 21
in effectNYC Admin. Code § 27-521.2 Classification.
§ 27-521.2 Classification.
An atrium shall be classified in occupancy group F-3.
NYC Admin. Code § 27-521.3 Construction.
§ 27-521.3 Construction.
(a) Atriums may be constructed only in buildings in noncombustible construction groups 1-A, 1-B and 1-C.
(b) An atrium shall be fully enclosed except that openings of any size into the two lowest levels of an atrium shall be permitted if such openings are provided with opening protectives having a fire-resistance rating of at least one and one-half hours or are provided with sprinklers no more than six feet apart.
(c) The minimum horizontal clear dimension of an atrium shall be forty feet, provided, however that this dimension can be reduced to twenty feet where sprinkler spacing on the occupied side adjacent to glass panels authorized by subdivision (d) of this section is no more than four feet or the minimum atrium area is twelve hundred square feet.
(d) Atrium enclosing walls shall be of at least two hour fire-resistant construction or of glass that is wired, laminated, or tempered and is provided with sprinklers on the occupied side spaced no more than six feet apart, except as otherwise permitted by subdivision (c) of this section.
NYC Admin. Code § 27-521.4 Fire protection equipment.
§ 27-521.4 Fire protection equipment.
(a) Smoke detectors. In all spaces opening onto an atrium, a smoke detecting system shall be installed in accordance with the requirements of reference standard RS 17-5E.
(b) Standpipes. At least one standpipe outlet in addition to a riser or risers within required stairways, shall be installed in every atrium.
(c) Sprinklers.
(1) Every story or mezzanine within an atrium that overhangs another story or mezzanine within fifty feet shall have the overhang sprinklered in accordance with section 27-956 of article four of subchapter seventeen of this chapter, except that atrium ceilings less than fifty feet above the atrium floor but more than thirty feet above the floor may alternatively be provided with smoke detectors, which shall be of the central supervisory type connected to an approved central station. Every room or space opening onto the atrium shall be sprinklered, no matter where located.
(2) Except as otherwise permitted by subdivision (c) of section 27-521.3 of this article, at glass panels permitted by subdivision (d) of such section, sprinklers on the occupied side at all levels shall be spaced six feet apart parallel to the glass and that distance away from the glass panels so as to insure complete glass wetting upon activation. No obstructions to such wetting capability shall be permitted.
(3) Every sprinkler system for an atrium shall be provided with sources of water supply in accordance with article four of subchapter seventeen of this chapter.
NYC Admin. Code § 27-521.5 Means of egress.
§ 27-521.5 Means of egress.
(a) No vertical exits shall discharge into an atrium at any level.
(b) Atrium corridors shall have a width equal to or greater than one hundred fifty per cent of that required by either table 6-1 of subchapter six or table 8-1 of subchapter eight, as applicable.
(c) An unenclosed path of travel to a required exit shall be permitted, except that access to one of the required vertical exits shall be only through an enclosed passageway or corridor conforming to the requirements for exits of subchapter six.
NYC Admin. Code § 27-521.6 Fire alarm and communication system.
§ 27-521.6 Fire alarm and communication system.
An interior fire alarm and communication system shall be installed in accordance with the requirements of reference standard RS 17-3.
NYC Admin. Code § 27-521.7 Signs.
§ 27-521.7 Signs.
Atriums shall be provided with all signs required by articles seven and nine of subchapter six of this chapter, regardless of the occupant load of the atrium.
NYC Admin. Code § 27-521.8 Smoke control.
§ 27-521.8 Smoke control.
(a) In all atriums there shall be provided a system of mechanical ventilation of sufficient capacity to exhaust at least six air changes per hour of the combined volumes of the atrium and all spaces with an open connection to the atrium, or 1 cfm/sq. ft. from all such spaces, whichever is greater, using either dedicated fan equipment or the building ventilation system arranged to shut down automatically, with manual override capability. Make-up air shall be supplied at the lowest level of an atrium at a rate equal to seventy-five percent of exhaust.
(b) All atriums shall have a gravity ventilation system equipped with remote manual controls to remove smoke if the mechanical exhaust system fails.
(c) A ventilation system serving an atrium shall not be interconnected with any other system serving another space.
(d) Ventilation systems supplying occupied spaces shall not be interconnected with the general atrium supply.
NYC Admin. Code § 27-521.9 Emergency power.
§ 27-521.9 Emergency power.
All atriums shall be provided with an emergency power system meeting the requirements of article eleven of subchapter six of this chapter.
Source: City of New York, Charter, Administrative Code and Rules (American Legal Publishing XML export, codelibrary.amlegal.com)URL: https://codelibrary.amlegal.com/codes/newyorkcity/latest/NYCadmin/0-0-0-50250Fetched: 10/24/2026