Prevention of Interior Fire Spread

NYC Admin. Code tit. 27, ch. 1, subch. 5, art. 5

in effect

NYC Admin. Code § 27-339 Fire segregation of occupancies.

§ 27-339 Fire segregation of occupancies. (a) Segregation by fire divisions. When different occupancies are to be segregated by fire divisions under the provisions of section 27-240 of subchapter three of this chapter, the occupancies shall be separated from each other, vertically and horizontally, by fire divisions having at least the fire-resistance ratings listed in table 5-2 for the occupancy groups involved. Every building section shall be constructed of elements having at least the fire-resistance rating of a construction class required for the area and height of the building section as listed in tables 4-1 and 4-2. (b) Segregation by fire separations. When different spaces are to be segregated by fire separations under the provisions of section 27-240 of subchapter three of this chapter, the occupancies shall be separated from each other, vertically and horizontally, by fire separations having at least the fire-resistance ratings listed in table 5-1. In buildings of construction group I, fire separations shall be constructed of noncombustible materials. TABLE 5-1 FIRE SEPARATIONS Occu-pancy A B-1 B-2 C D-1 D-2 E F-1a F-1b F-2 F-3 F-4 G H-1 H-2 J-1 J-2 J-3 A 4 4 4 4 4 4 4c 4 4 4 4 4 4 4 4 4 4 4 B-1 4 3 NR 1bc NR NR 1ac 1c 1c - 1c 1c 1c 11/2c 11/2c 1c 1c 1c B-2 4 3 2 NR NR NR NR NR NR - NR NR NR NR NR NR NR NR C 4 3 2 2 1 NR NR NR NR - NR NR NR 1 1 1 1 1 D-1 4 3 3 3 3 NR 1a 1 1 - 1 1 1 1 1/2 1 1/2 1 1 1 D-2 4 3 2 2 3 2 NR NR NR - NR NR NR NR NR NR NR NR E 4 3 2 2 3 2 2 NR NR - NR NR NR 1a 1a 1a 1a 1a F-1a 4 3 2 2 3 2 2 2 NR - NR NR NR 1 1 1 1 1 F-1b 4 3 2 2 3 2 2 2 2 - NR NR NR 1 1 1 1 1 F-2 4 3 2 2 3 2 2 2 2 2 - - - - - - - - F-3 4 3 2 2 3 2 2 2 2 2 2 NR NR 1 1 1 1 1 F-4 4 3 2 2 3 2 2 2 2 2 2 2 NR 1 1/2 1 1/2 1 1 1 G 4 3 2 2 3 2 2 2 2 2 2 2 2 NR NR NR NR NR H-1 4 3 2 2 3 2 2 2 2 2 2 2 2 2 NR 1 1 1 H-2 4 3 2 2 3 2 2 2 2 2 2 2 2 2 2 1 1 1 J-1 4 3 2 2 3 2 2 2 2 2 2 2 2 2 2 2 NR NR J-2 4 3 2 2 3 2 2 2 2 2 2 2 2 2 2 2 2 NR J-3 4 3 2 2 3 2 2 2 2 2 2 2 2 2 2 2 2 2 TABLE 5-2 FIRE DIVISIONS Key: Fire-resistance ratings are given in hours. For Table 5-1 read above heavy line. For Table 5-2 read below heavy line. NR means No Requirement. Notes for Tables 5-1 and 5-2: a An office, or group of offices, whose use is accessory to an occupancy, and totals four hundred square feet or less in area shall not be required to have a fire separation. Such office, or group of offices, totalling more than four hundred square feet in area shall not be required to have a fire separation if such offices exit directly, without having to pass through the area of the related occupancy. b Counters and backbars for the sale of publications, tobacco products, liquors, or candies, or for making of reservations for travel, car rental, or theatre, or otherwise involving similar business and mercantile activities that are accessory to an occupancy and are limited in area to one hundred square feet, within the area of the occupancy, need not comply with the requirements of this table. c The provisions of this table shall not apply to closets seventy-five square feet or less in area. d Nonresidential kitchens need not be separated by fire separations from adjoining dining spaces, provided: (1) The cooking equipment is vented directly to the outdoors, and (2) 2 draft curtain of noncombustible material, at least twenty-four inches down from the ceiling, is provided to separate the cooking facilities from dining spaces, and (3) Sprinkler heads constructed in accordance with the provisions of subchapter seventeen of this chapter, are provided on the cooking facilities side of the curtain, or any opening between the kitchen and dining space, located within twenty-four inches of the curtain or opening, and spaced not more than forty-eight inches on centers if the opening is more than sixty inches wide. When fire separations are provided double-action doors may be permitted. e Kitchens having a floor area of fifty-nine square feet or less located within dwelling units shall be separated from adjacent spaces by partitions having a fire-resistance rating of at least one hour except for the entrances thereto which need comply with section 27-342 of this article. If doors are provided they may be of wood. f In buildings or spaces classified in occupancy group J-1 or J-2 all partitions in dwelling units located in cellars shall have a minimum fire-resistance rating of one hour. (c) Compartmentation. Notwithstanding the provisions of table 4-1, in existing office buildings one hundred feet or more in height having air-conditioning and/or mechanical ventilation systems that serve more than the floor on which the equipment is located, unsprinklered floor areas, more than forty feet above curb level, shall be subdivided by fire separations into spaces or compartments of the size required by paragraphs one through five of this subdivision. Floor area shall be defined as the area within exterior walls and excluding any areas enclosing stairs, corridors, elevators and shafts: (1) Unless otherwise provided below, all unsprinklered floor areas shall be segregated by one-hour fire separations into spaces or compartments not to exceed seventy-five hundred square feet. (2) Where the floor area exceeds ten thousand square feet, at least one of the subdividing fire separations shall be of two-hour fire-resistive construction, creating areas of refuge, complying with section 27-372 of article five of subchapter six of this code except that the requirement for an elevator in each area shall not apply. (3) The floor area or any subdivided area may be increased to not more than fifteen thousand square feet if complete area protection by approved devices for the detection of products of combustion other than heat is provided within such increased area and provided further than at least one of the subdividing fire separations shall be of two-hour fire-resistive construction where the floor area exceeds fifteen thousand square feet, creating areas of refuge in the same manner and under the same conditions as provided in two of this subdivision. The activation of any such detectors shall have the same effect as provided in subdivision (f) of section 27-972 of article five of subchapter seventeen of this code. (4) In existing buildings, existing fire separations of one-hour fire-resistive construction may be accepted in lieu of the fire separation of two hour fire-resistive construction providing all other requirements of paragraphs two and three of this subdivision are complied with. (5) Regardless of the floor area, no subdivision of the floor area shall be required under this subdivision when complete sprinkler protection is provided in accordance with the construction provisions of subchapter seventeen of this chapter. (6) Existing office buildings one hundred feet or more in height shall comply with the requirements of this subdivision as follows: a. Whenever an alteration is performed involving partition changes, compliance with this subdivision shall be required in that portion of the building being altered. b. At least one-third of the total floor area of the building not in compliance with the requirements of this subdivision on February seventh, nineteen hundred seventy-three, shall comply with such requirements on or before December thirteenth, nineteen hundred eighty-one. Complete plans showing such compliance for the phase of the work to be done shall be filed with, and a permit secured from, the commissioner on or before September thirteenth, nineteen hundred eighty. c. At least two-thirds of the total floor area of the building not in compliance with the requirements of this subdivision on February seventh, nineteen hundred seventy-three, shall comply with such requirements on or before August seventh, nineteen hundred eighty-four. d. Full compliance shall be provided on or before February seventh, nineteen hundred eighty-eight. (7) In existing office buildings one hundred feet or more in height where compliance would cause practical difficulty or undue hardship, the commissioner may waive or modify the requirements of paragraphs one through five of this subdivision and accept alternatives fulfilling the intent of these requirements. Where compliance with the time requirements of paragraph six of this subdivision would cause undue hardship, the commissioner, with the approval of the fire commissioner, may extend the time for compliance, in accordance with rules and regulations to be promulgated. Before such application for a time extension shall be considered all required applications and plans must be filed and approved, permits obtained and a good faith effort towards completion of the work shall have been made.

NYC Admin. Code § 27-340 Fire divisions.

§ 27-340 Fire divisions. Fire divisions shall be constructed of noncombustible materials or assembly of noncombustible materials to provide the fire-resistance ratings required by table 5-2. Vertical fire divisions shall be continuous between foundation, roof, or horizontal fire divisions, and through any concealed space in floor or roof construction. Horizontal fire divisions shall be continuous between exterior walls and/or vertical fire divisions. (a) When roof construction is combustible on both sides of a vertical fire division, the vertical fire division shall extend through the roof construction to a height of at least four inches above the high point at the roof framing. Decking shall tightly butt the fire division. Above the decking of roofs that are flatter than twenty degrees to the horizontal, blocking shall be constructed to form cants on both sides of the fire division with slopes not steeper than 1:4. Combustible decking shall not extend over the top of the fire division. (b) Except as required in subdivision (c) of this section, when roof construction is noncombustible on one or both sides of a vertical fire division, the vertical fire division may terminate at the underside of the noncombustible roof construction provided the junction of the wall and roof construction is made smoke tight. (c) When a vertical fire division is required by table 5-2 to have a fire-resistance rating of three or four hours, and the roof construction has a fire-resistance rating of less than two hours, the fire division shall extend above the roof construction to form a parapet at least three feet high. (d) Fire divisions shall be so constructed that the removal or collapse of construction on one side will not endanger the support of construction on the other side. (e) Fire divisions shall be made smoketight at their junction with exterior walls. In buildings of construction class II-D and II-E, exterior walls shall be constructed of noncombustible materials for a distance of at least eighteen inches on each side of the fire division, or the fire division shall project at least twelve inches through the exterior wall. (f) Fire divisions may be offset if the construction between the offset divisions, including their supports, has at the same fire-resistance rating as the fire division, with all hollow spaces within the construction firestopped with noncombustible material. (g) Where combustible members such as joists, beams, or girders bear on, or frame into, vertical fire divisions, such members shall not extend through the wall and shall have at least four inches of solid noncombustible material below, at the sides, and at the ends of each such member. (h) Chases or recesses shall not be cut into fire divisions so as to reduce their thickness below that required for the fire-resistance rating. (i) Vertical fire divisions that are hollow shall be firestopped with at least four inches of noncombustible material so as to prevent passage of flame, smoke, or hot gases through the hollow spaces to the story above or below, or to hollow spaces within connecting floor or roof construction.

NYC Admin. Code § 27-341 Fire separations.

§ 27-341 Fire separations. Fire separations shall be constructed of materials or assembly of materials having at least the fire-resistance ratings required by table 5-1. (a) Different tenancies. Different tenant apartments, suites, stores, offices, or other spaces that are not separated from each other by fire divisions, shall be separated from each other by fire separations having at least the fire-resistance rating prescribed in table 5-1, but in no case less than one hour, and shall continue through any concealed spaces of the floor or roof construction above.

NYC Admin. Code § 27-342 Openings in fire divisions and separations.

§ 27-342 Openings in fire divisions and separations. Openings in fire divisions and fire separations that are required to have a fire-resistance rating, shall be protected by opening protectives having the fire-resistance ratings prescribed in table 5-3, shall not exceed the limits in size and area herein prescribed, and shall comply with the provisions of section 27-329 of article three of this subchapter. Door and other openings in enclosures of vertical exits, exit passageways, corridors, and places of assembly shall be protected by opening protectives as required by the provisions of subchapters six and eight of this chapter. When such enclosures also serve as fire divisions or fire separations, openings therein shall be protected as required by the provisions of this subchapter. (a) Size of opening. In buildings that are not sprinklered no opening through a fire division or fire separation shall exceed one hundred twenty square feet in area, with no dimension greater than twelve feet, and the aggregate width of all openings at any level shall not exceed twenty-five percent of the length of the wall. Where the areas on both sides of a fire division or fire separation are sprinklered in accordance with the construction provisions of subchapter seventeen of this chapter, the size of the opening may be one hundred fifty square feet in area, with no dimension greater than fifteen feet. In buildings fully sprinklered in compliance with the provisions of subchapter seventeen of this chapter, the size and aggregate width of openings through fire divisions or fire separations shall be unlimited. When a fire division or fire separation serves as a horizontal exit also, it shall have no opening other than door openings not exceeding fifty-six square feet in area, the aggregate width of all openings at any level shall not exceed twenty-five percent of the length of the wall, and shall comply with the provisions of section 27-373 of article five of subchapter six of this chapter. (b) Conveyor openings. Where fire doors or shutters are impractical for the protection of conveyor openings in fire divisions or fire separations, a system of water spray nozzles may be used. At least four nozzles shall be provided on each side of the opening so as to give complete coverage of the opening. Nozzles shall be controlled by an automatic valve actuated by a heat detector. Nozzles shall be located at an angle not more than thirty degrees between the centerline of nozzle discharge and a line perpendicular to the plane of the opening. The water discharge rate shall be at least three gallons per square foot per minute. When conveyor openings through floors are protected by this method, the openings shall also be provided with a noncombustible enclosure constructed around the conveyor from the floor up to or slightly beyond the spray nozzles, and draft curtains shall be provided extending twenty-four inches below and around the floor opening. TABLE 5-3 Opening Protectives for Fire Divisions and Fire Separations Fire-Resistance Rating of Fire Division or Fire Separation in which Opening Occurs (hr.) Fire Protection Rating of Opening Protective 3 or 4 3 hr. (Class A)* 2 or 1 1/2 1 1/2 hr. (Class B)* 1 3/4 hr. (Class C)* * Note – Shall consist of two one and one-half hour (class B) opening protectives, with one protective installed on each face of a fire division or fire separation.

NYC Admin. Code § 27-343 Ducts, pipes and conduits through rated construction.

§ 27-343 Ducts, pipes and conduits through rated construction. (a) Installation of ducts which pass through construction required to have a fire-resistance rating shall comply with the requirements of subchapter thirteen, provided that, notwithstanding the provisions of subchapter thirteen or reference standard RS 13-1, noncombustible ducts which pass through construction required to have a fire-resistance rating of one hour must be provided with fire dampers unless: (1) The building is classified in occupancy group C, E, or H-2; and (2) Complete sprinkler protection is provided for the floor in accordance with subchapter seventeen; or (3) The openings for the ventilation ducts do not exceed three square feet in area; or (4) The duct is protected on both sides of the partition for a distance equal to the maximum duct dimension by a sleeve affording one hour fire separation for such horizontal distance. (b) Noncombustible pipes and conduits. Noncombustible pipes and conduits may pass through construction required to have a fire-resistance rating provided that the space between the pipe or conduit and its sleeve or opening does not exceed one-half inch and is completely packed with mineral wool or equivalent noncombustible material and is closed off by close-fitting metal escutcheons on both sides of the construction; and provided further that the aggregate net area of such openings does not exceed twenty-five square inches in any one hundred square feet of wall or floor area (excluding the areas of openings for sleeves which are firestopped in conformance with this section and section 27-345). (c) Openings for passage of pipe and ducts whose aggregate net area exceeds twenty-five square inches in any one hundred square feet of wall or floor area (excluding opening for sleeves which are firestopped in conformance with this section and section 27-345) may pierce constructions required to have a fire-resistance rating only when the type of construction to be used has been tested with such types of facilities installed in place and the proportionate area of openings of such facilities to be installed in the construction does not exceed the proportionate area of openings in the assembly tested, and provided no opening is larger than that in the assembly tested. Protection of such openings shall be the same as provided in the test. All openings through hollow fire rated construction shall be sleeved with sheet metal least No. 14 U.S. std. gage thick. (d) The installation and proper functioning of required fire dampers shall be subject to the controlled inspection requirements of section 27-132 of this code, except that it shall not be required that the architect or engineer be in the employ of the owner.

NYC Admin. Code § 27-344 Shafts.

§ 27-344 Shafts. The requirements of this section shall apply to all shafts, except that floor openings accommodating a slide pole in a fire house and openings other than for ventilation, chimneys or gas vents in buildings three stories or less in height classified in occupancy group J-3 shall be exempt from these requirements, and except as more restrictive requirements may be specified for chimneys and gas vents in subchapter fifteen of this chapter, stairway enclosures in subchapter six, duct enclosures in subchapter thirteen, elevator, escalator, and dumbwaiter enclosures in subchapter eighteen of this chapter, and except as permitted in reference standard RS 5-18. (a) Construction. Shafts shall be enclosed with materials having at least fire-resistance rating required by table 3-4. A shaft that serves the topmost story of a building shall extend through the roof at least thirty-six inches above any combustible roof construction. Where the roof construction is of noncombustible materials, the shaft shall extend through any concealed space within the roof construction and may terminate at the underside of the roof deck. Pipes and ducts penetrating shaft construction shall comply with the requirements of section 27-343 of this article. (b) Combustible Contents. Shafts shall be kept free of bookstacks or other combustible contents except for stair construction as permitted under subchapter six of this chapter, duct and pipe coverings as permitted under subchapters thirteen and sixteen, and elevator car enclosures as permitted under subchapter eighteen of this chapter. (c) Openings in shafts. All shaft openings below the top terminus shall be provided with opening protectives that comply with section 27-329 of this subchapter and table 5-3. In shafts that contain only one opening below the roof terminus, no opening protective need be provided. Openings in elevator and dumbwaiter shafts shall comply only with the requirements of subchapter eighteen of this chapter. Where a window is located in a shaft wall that is an exterior wall and is ten stories or less above grade or three stories or less above a roof, it shall be protected against entrance by a permanently secured grille consisting of 5/8 in. dia. bars, 10 in. o. c. vertically, or by a stationary metal sash window having 1/8 in. thick solid section steel muntins, 8 in. o. c. one way. This protection shall not be required in stair shafts where there is a stair landing or platform not more than three feet directly below the window sill. (d) Smoke venting of closed shafts. All closed shafts having an area exceeding four square feet, other than elevator or dumbwaiter shafts, shall be provided with a smoke vent having an area of at least three and one-half percent of the maximum shaft area at any floor, but in no event less than one-half square foot. Elevator and dumbwaiter shaft vents shall comply with the requirements of subchapter eighteen of this chapter. Smoke vents may be windows, louvers, skylights, vent ducts, or similar devices. Vent ducts shall be enclosed by construction having the same fire resistance rating as required for the shaft enclosure. Such vent ducts shall extend vertically, diagonally, or horizontally as provided below. (1) Through any roof of the building provided the vent opening is at least ten feet from any window, door, outside stairway, or interior lot line. This dimension may be reduced to five feet if the vent duct is extended up to at at least the level of the top of the window or door. A vent that is required to extend above a roof shall extend at least eight inches above a roof assembly constructed of noncombustible materials, and at least thirty-six inches above a roof assembly constructed of combustible materials that are within a horizontal distance of ten feet. (2) Through an exterior wall of the building, provided there are no openings in the wall within a distance of thirty feet vertically above the vent opening, and within five feet either side of the vent opening. When a side of a shaft is an exterior wall or a wall of a roof bulkhead, the required vent may be a louver or window. Any window or louver located in a shaft wall above a roof constructed of combustible materials shall have its sill at least thirty-six inches above the roof. (e) Terminus of shaft vents. Of the total required vent area for shafts, at least one-third shall be clear opening to the outdoors, either in the form of fixed louvers, ridge vents, or hooded or goosenecked openings. In lieu thereof, skylights or trap doors may be used if constructed and arranged to open automatically by fusible link or other mechanical device when subjected to a temperature of one hundred sixty degrees Fahrenheit or to a rapid rise in temperature at a rate of fifteen to twenty degrees Fahrenheit per minute. The remaining portion of the required vent area may be a window or skylight glazed with plain glass not more than one-eighth inch thick or slow burning plastic. (f) Machine rooms. Any compartment containing machinery that communicates with a shaft enclosure shall comply with all requirements for shafts. The required louver or glazing shall not be located in any door leading into such compartment.

NYC Admin. Code § 27-345 Firestopping.

§ 27-345 Firestopping. Concealed spaces within partitions, walls, floors, roofs, stairs, furring, pipe spaces, column enclosures, etc. that would permit passage of flame, smoke, fumes, or hot gases from one floor to another floor or roof space, or from one concealed area to another, shall be firestopped to form an effective draft barrier, or shall be filled with noncombustible material in accordance with the requirements of this section. Firestopping shall not be required where a concealed space is sprinklered in accordance with the construction provisions of subchapter seventeen of this chapter, or is constructed as a shaft. (a) Firestopping materials. In buildings of construction group I, firestopping or fill shall be of noncombustible material that can be shaped, fitted, and permanently secured in position. In buildings of construction group II, firestopping may be of combustible material consisting of wood not less than two inches nominal thickness with tight joints, two layers of one inch nominal thickness assembled so that there are no through joints or of one-half inch exterior type plywood with joints backed, except that noncombustible firestopping shall be used in concealed spaces of fire divisions and where in contact with fireplaces, flues, and chimneys. Noncombustible firestopping may be masonry set in mortar, concrete, three-quarter inch thick mortar or plaster on noncombustible lath, plasterboard at least three-eighths of an inch thick, fire-rated wallboard at least five-eighths of an inch thick, sheet metal at least No. 14 U.S. std. gage thick, solid web metal structural members, asbestos-cement board at least one-quarter of an inch thick, or equivalent rigid noncombustible material. Mineral, slag, or rockwool may be used for firestopping when compacted to a density of at least three and one-half pounds per cubic foot into a confined space of least dimension not more than one-third its second dimension. (1) The performance of through-penetration fire stops shall be measured and specified according to reference standard RS 5-19. (2) The commissioner may accept reference standard RS 5-19 test data results from an independent laboratory acceptable to the commissioner pursuant to subdivision (c) of section 27-131, when such data is submitted by a registered architect or licensed professional engineer to justify the usage of fire stops or the details of their installation not specified herein. (b) Hollow partitions and furred spaces. All hollow partitions and furred out spaces shall be firestopped at each floor level. Firestops shall be the full thickness of the hollow space or furred out space. (c) Stairs. Concealed spaces within stair construction shall be firestopped between stringers at the top and bottom of each flight of stairs so as not to communicate with concealed spaces in the floor, roof or intermediate landing construction. (d) Ceiling spaces. Floor or roof assemblies required to have a fire-resistance rating shall have any concealed spaces therein firestopped in accordance with section 27-327 of this subchapter. (e) Exterior cornices. Exterior cornices and eaves, constructed of combustible materials or with combustible framing, shall be firestopped at the ends of fire divisions and party walls, and at maximum intervals of twenty feet. If not continuous, they shall have closed ends and at least four inches separation between adjoining sections. (f) Trim and finish. Where combustible trim and finish is permitted all hollow spaces shall be firestopped at ten foot intervals or shall be solidly filled with noncombustible materials. (g) Duct and pipe spaces. Ducts and pipes enclosed in construction that does not meet the requirements of this code for shaft construction shall be firestopped at every floor level. (h) Inspection of firestopping. The installation of all required firestopping shall be subject to the controlled inspection requirements of section 27-132 of article seven of subchapter one of this chapter, except that the architect or engineer need not be retained by the owner. Firestopping shall not be concealed from view until inspected.

NYC Admin. Code § 27-346 Partitions and furring.

§ 27-346 Partitions and furring. In buildings of construction group I, partitions and furring shall be constructed of noncombustible materials, except that nonbearing partitions that are not required to have a fire-resistance rating, and furring may be constructed of fire retardant treated wood as provided in subdivision (d) of section 27-328 of article three of this subchapter, and except that such partitions and furring, may be constructed of combustible materials in spaces classified in occupancy group E, J-2, or J-3, provided the following conditions are met: (a) the space containing the combustible partitions does not exceed five thousand square feet in area within a noncombustible enclosure having a fire-resistance rating of at least one hour. (b) the space is in a single tenancy. (c) glass or slow burning plastic is used for glazing.

NYC Admin. Code § 27-347 Folding partitions.

§ 27-347 Folding partitions. Folding partitions shall not be used as partitions that are required by this code to have a fire-resistance rating. (a) Construction group I. In buildings of construction group I, folding partitions may be used if they are constructed of noncombustible materials, or of fire retardant treated wood, or are constructed of noncombustible frame covered with fabric that has a class A interior finish rating. Where partitions of combustible materials are permitted by section 27-346 of this article, folding partitions may also be constructed of combustible materials. Where doors constructed of materials having a class C interior finish rating are permitted by section 27-348 of this article, folding doors may be constructed of combustible materials. (b) Construction group II. In buildings of construction group II, folding partitions may be constructed of combustible materials, surfaced with interior finish materials meeting the requirements of section 27-348 of this article.

NYC Admin. Code § 27-348 Interior finish.

§ 27-348 Interior finish. (a) Definition. For the purposes of this section, interior finish shall mean those materials that form the exposed interior surfaces of a building and that are part of or affixed to walls, fixed or folding partitions, ceilings, and other construction elements. (b) Classification. Interior finish materials shall be classified in accordance with the surface flame-spread rating obtained as prescribed in the provisions of reference standard RS 5-5. Where an interior finish material is comprised of two or more materials laminated, glued, nailed, or otherwise secured together, the test rating for flame spread shall be based upon the composite of the materials in the form in which it will be used in construction. Interior finish materials shall be grouped in the following classes, in accordance with their surface flame spread characteristics: Interior Finish Class Flame-Spread Rating A 0 to 25 B 26 to 75 C 76 to 225 D Over 225 (c) Requirements. Interior finishes and exposed structural or construction materials shall have a flame-spread rating not greater than that designated by the class prescribed for the various occupancy groups in which they are used, as listed in table 5-4. Exceptions to these requirements are: (1) Finish flooring and floor coverings, which are subject to the requirements of section 27-351. (2) Wall coverings and coatings that are less than 0.036 in total thickness, when applied directly to a noncombustible, or fire-retardant treated wood, substrate. (3) Exposed structural members and planking in buildings of class II-A construction, which may be left exposed in any room or space, except in exits. (4) Twenty per cent (20%) of the aggregate wall and ceiling area of any room, space, or corridor required to have a class A or B rating may be finished with materials having a class C rating. This allowance shall include the area of doors, folding partitions, windows, glazing, skylights, luminous ceilings, trim, bases, chair rails, panels, moldings, etc. This exception shall not operate as a waiver of other requirements of this code relating to opening protectives. (5) When a sprinkler system is provided in any room or space, and is installed in compliance with the construction provisions of subchapter seventeen of this chapter, interior finish materials may be one class higher in flame-spread rating than required by tables 5-4. (d) Smoke density. No material shall be used for interior finish in the following locations if the material develops smoke in greater density than the rating shown, based upon a test conducted in accordance with the provisions of reference standard RS 5-5. Materials used for interior finish that cover not more than twenty percent of the aggregate wall and ceiling area of any room, space, or corridor shall be exempt from the above requirements. Location or Occupancy Smoke Developed Rating Exits, corridors 25 Occupancy groups H-1 and H-2 50 Rooms in which the net floor area per occupant is ten square feet, or less 100 (e) Toxicity. No material shall be used in any interior location that, upon exposure to fire will produce products of decomposition or combustion that are more toxic in point of concentration than those given off by wood or paper when decomposing or burning under comparable conditions. (f) Attachment of interior finish. (1) To be credited with the same rating, interior finish materials that were applied to a substrate when tested shall be applied at the building to an equivalent substrate. (2) Interior finish materials shall be cemented or otherwise secured in place in the same manner and with materials equivalent to those used in flame-spread tests conducted in accordance with subdivision (b) of this section for the applicable classification. (3) Where walls, ceilings, partitions, or other construction elements are required to have a fire-resistance rating or are required to be constructed of noncombustible materials, and the interior finish is secured to studs or furring, the surface of the interior finish facing the concealed space shall either have a class A rating, shall be applied to a substrate that has a class A rating, or shall have the concealed space completely filled with noncombustible material. TABLE 5-4 Interior Finish Requirements Class Occupancy Group Classification of the Space Occupancy Group Designation Exits and Shafts Corridors b Rooms More Than 1,500 Sq. Ft. in Area a Rooms Less Than 1,500 Sq. Ft. in Area a, d High Hazard A A A B B Storage B-1 A A B C Storage B-2 A B B c C Mercantile C A B B c C Industrial D-1 A A B C Industrial D-2 A B B c C Business E A B C C Assembly F-1a A B B Bd Assembly F-1b A B B c B c, d Assembly F-2 A B B c B c, d Assembly F-3 A B B c B c, d Assembly F-4 A B B c C Educational G A A B C Institutional H-1, H-2 A A B B d Residential J-1, J-2 A A B B f Residential J-3 B D e De De Notes For Table 5-4: a In determining the applicable requirements for rooms or enclosed spaces, the occupancy group classification of the room or enclosed space shall be the governing factor, regardless of the occupancy group classification of the building. For the purposes of this table, the area of a room shall be that floor area contained within enclosing construction in which interior doors or other interior openings represent not more than ten percent of the area of the enclosing construction. Interior doors or windows that are constructed of noncombustible materials and that are self-closing or automatic may be ignored in computing door or opening area. Rooms or spaces that have unprotected openings constituting more than ten percent of the area of enclosing construction shall not be considered as a room. Interior finish requirements for rooms are based upon rooms being enclosed in ceiling high partitions. Partitions, to be considered ceiling high, shall extend up to the floor or roof construction above or to a ceiling having at least a three-quarter hour fire-resistance rating. Partitions that do not comply with this requirement shall not be considered as enclosing the spaces, and the rooms or spaces on both sides thereof shall be considered as one. b Rooms or spaces through which it is necessary for occupants of an adjacent room to pass in order to reach the only exit shall, for the purposes of this table, be considered as corridors. Where used in corridors, class B finish material shall not extend more than fifty feet between separations of class A finish material that are at least two feet wide. c On the street floor of one-story buildings in construction group II, ceilings, beams, trusses, etc. that are twenty feet or more in height from the floor to their lowest part, may have a class C finish. d Class C interior finish may be used in offices, or groups of offices, whose use is accessory to an occupancy, provided such offices are separated from the occupancy, by construction having at least a two hour fire-resistance rating. e Class C interior finish may be used in the residential rooms of one- and two-story motels when there is a direct exit from each room to the exterior. f Interior finish when used in the following spaces shall be at least class B: (1) Kitchens, cooking spaces, and pantries in buildings classified in occupancy groups other than J-2 and J-3. (2) Repair and maintenance rooms. (3) Boiler rooms and incinerator combustion rooms.

NYC Admin. Code § 27-349 Coatings.

§ 27-349 Coatings. Coatings applied in the field by brush or spray shall not be used as flame-spread retardants except on existing surfaces of buildings existing on December sixth, nineteen hundred sixty-eight, and then only with the express permission of, and in a manner directed by, the commissioner.

NYC Admin. Code § 27-350 Ceiling construction.

§ 27-350 Ceiling construction. Ceilings that are to be suspended below floor or roof construction by means of a framing system shall consist of supporting hangers, carrying channels and a supporting grid complying with reference standard RS 5-16 or shall have supporting hangers and carrying channels and a supporting grid that can be demonstrated to the satisfaction of the commissioner to be of strength adequate to support the ceiling material. The hangers and supporting grid shall be of noncombustible materials. In buildings of construction group II, every other hanger supported from wood members shall be attached by a through bolt or clinched through nail. Where, in table 3-4, floor or roof construction is required to have a fire-resistance rating, a ceiling having no fire-resistance rating may be suspended below the fire-resistance construction. (a) Luminous ceilings. For the purpose of this section, a luminous ceiling shall be defined as a ceiling consisting of translucent, louvered, egg-crated, mesh, or similar light-diffusing material suspended from the ceiling or structural framework. A suspended ceiling containing less than twenty square feet of translucent, louvered, egg-crated, mesh, or similar material in any one hundred square feet of ceiling area shall not be considered a luminous ceiling, and shall be constructed and installed in accordance with department of buildings requirements for lighting fixtures. Luminous ceilings shall, in addition to the requirements of this section, conform to all of the requirements of section 27-348 of this article for interior finish. (1) LUMINOUS CEILINGS OF NONCOMBUSTIBLE MATERIAL. Luminous ceilings constructed of glass and/or metal or other noncombustible materials may be used in any location. a. Glass used in luminous ceilings, unless it is wire glass or heat-resistant glass as specified below, shall not weigh more than two psf, nor shall any pane be larger than eight square feet in area. If glass used in luminous ceilings is wire glass, or is heat resistant by reason of having a maximum coefficient of expansion of 36 x 10-7 in. per in. per degree C, the glass may be of any weight and any size, limited only by considerations of structural safety. b. Luminous ceilings installed below sprinkler heads shall be constructed of a type of noncombustible louver, mesh, or other open material that will not impede the flow of water from the sprinkler heads over the intended area of coverage. The luminous ceiling shall be constructed so as to provide access to all heads and valves. (2) LUMINOUS CEILINGS OF COMBUSTIBLE MATERIAL. Luminous ceilings constructed of combustible materials shall not be installed in: a. Any exit or corridor. b. Any room classified in occupancy group H, or any room leading therefrom as defined in note b of table 5-4. c. Any room in which the net floor area per occupant is twenty square feet or less, or any room leading therefrom as defined in note b of table 5-4. d. Luminous ceilings constructed elsewhere than in the spaces listed in subparagraphs a, b, and c above shall be exempt from the provisions of section 27-348 of this article, provided that: 1. The panels of such ceilings are of slow-burning plastic; 2. The panels are installed above or below sprinklers that are constructed in accordance with the provisions of subchapter seventeen of this chapter; 3. No individual plastic panel exceeds ten feet in maximum dimension. Where installed below sprinkler heads, the plastic shall be a material that will fall from its mounting at a temperature at least fifteen degrees lower than the temperature at which the sprinkler heads are designed to operate or are constructed of open material which will not impede the flow of water from the sprinkler heads. Luminous ceilings shall be installed so as to provide ready access to all heads and valves. (b) Suspension of new ceilings below existing suspended ceilings. In construction group I a new ceiling may be suspended below not more than one existing suspended ceiling and shall be supported directly from the ceiling carrying channels adjacent to the hangers. In construction group II, an existing suspended ceiling shall be completely removed before a new ceiling may be suspended. Editor's note: For related unconsolidated provisions, see Appendix A at L.L. 1996/059.

NYC Admin. Code § 27-351 Finish flooring and floor coverings.

§ 27-351 Finish flooring and floor coverings. Finish flooring and floor coverings shall comply with the following: (a) In buildings or spaces classified in occupancy group A and in all exits except those in buildings of construction group II-E, finish flooring shall be of noncombustible material and except as otherwise provided for stairs in subdivision (h) of section 27-375 of article five of subchapter six of this chapter. (b) Flooring in buildings or spaces of construction group I. Except as provided in subdivision (a) of this section combustible finish flooring may be used in buildings or spaces of construction group I when cemented directly to the top surface of noncombustible floor construction, or attached to combustible or noncombustible sleepers. When attached to sleepers, the space between the noncombustible floor construction and the bottom of flooring shall be solidly filled with noncombustible material to within one-quarter inch of the flooring, or the space between the sleepers under the flooring shall be firestopped into areas of not more than twenty square feet, and provided further that no open spaces shall extend under or through fire divisions or through fire separations. Combustible insulating or sound absorbing boards not more than one-half inch thick and having a flame-spread rating not greater than class C may be used when attached directly to noncombustible floor construction and covered with finish flooring. (c) Flooring in buildings or spaces of construction group II. Except as provided in subdivision (a) of this section, finish flooring in buildings or spaces of construction group II may be of combustible material. (d) Floor coverings. (1) Exits. Where exits are required under any provision of this code, carpets and carpet assemblies shall not be installed in such exits, except that wool carpeting may be installed in lobby areas, exit passageways and convenience stairs. (2) Flammability requirements. The requirements of this subdivision shall apply to carpets and carpet assemblies only when used as a floor covering (for requirements pertaining to carpets and carpet assemblies used as interior finishes, see section 27-348 of this article). For purposes of this subdivision, carpeting assemblies shall include the carpet, its underlay, and adhesives which when tested as a composite shall be representative of the proposed installation. a. Pill test. All carpets and underlayments shall pass a methanine pill test in accordance with the requirements of reference standard RS 5-20. b. Critical radiant flux test. Carpets and carpet assemblies shall be tested by the method for critical radiant flux in accordance with the requirements of reference standard RS 5-20. The time frame for such test shall be at least a fifteen minute exposure. 1. Carpets and carpet assemblies representative of the actual installation on floors of corridors, shall have a minimum critical radiant flux of 0.5 watts per square centimeter (W/cm). 2. Carpets and carpet assemblies representative of the actual installation on floors of general areas shall have a minimum critical radiant flux of 0.4 W/cm. c. Smoke developed ratings. Carpets and carpet assemblies representative of the actual installation on floors of corridors or general areas shall be tested for smoke developed ratings in accordance with the requirements of reference standard RS 5-20. The smoke developed ratings in either the flaming or no-flaming mode shall not exceed three hundred within the first four minutes of the test. d. The manufacturer of the carpets and carpet assemblies shall submit a certificate from an independent laboratory acceptable to the commissioner pursuant to section 27-131, showing the complete test data results, prior to final acceptance. The certification shall state that the material is treated for fire resistance and shall indicate the service life of the treatment or that the material is inherently fire resistant by virtue of its construction, chemical properties and/or composition. Materials which are not inherently fire resistant may be used only when the certified fire resistant service life exceeds that of the planned service life of the carpets and carpet assemblies with consideration being given to cleaning, traffic, and other conditions of use which may affect the treatment. (3) Volatile organic compounds emissions in carpet and carpet cushion. On and after July 1, 2013 carpet and carpet cushion as defined in section 17-1401 of the administrative code shall comply with the limits on volatile organic compound emissions set forth in chapter 14 of title 17 of such code.

NYC Admin. Code § 27-352 Fireplaces. [Repealed]

NYC Admin. Code § 27-353 Smoke and heat venting.

§ 27-353 Smoke and heat venting. (a) Where the floor area of a one-story building classified in occupancy group A, B-1, or D-1 is greater in depth than one hundred feet from a frontage space, that portion beyond one hundred feet shall be provided with roof vents and smoke curtains complying with the requirements of reference standard RS 5-11. Where the effective area of vents are glazed with plain glass or plastic not thicker than one-eighth inch, they need not be provided with automatic opening devices. (b) Buildings classified in occupancy group E, one hundred feet or more in height, having air-conditioning and/or mechanical ventilation systems that serve more than the floor on which the equipment is located, shall be provided with at least one smoke shaft by means of which smoke and heat shall be mechanically vented to the outdoors as provided in reference standard RS 5-17. Buildings that are sprinklered throughout shall be exempt from the smoke shaft requirements. (c) Existing office buildings, one hundred feet or more in height, having air-conditioning and/or mechanical ventilation systems that serve more than the floor on which the equipment is located, shall be provided with at least one smoke shaft by means of which smoke and heat shall be mechanically vented to the outdoors as provided in reference standard RS 5-17, or in lieu of such smoke shaft or shafts, all interior enclosed stairs other than a fire tower or access stairs may be provided with a system of pressurization for fire emergency use. Such pressurization shall be provided by means of a system or systems as provided in reference standard RS 5-18. Such buildings shall comply with the smoke and heat venting requirements herein on or before September thirteenth, nineteen hundred eighty-two. Complete plans showing such compliance shall be filed with, and a permit secured from, the commissioner on or before September thirteenth, nineteen hundred eighty. Existing buildings that are sprinklered throughout shall be exempt from the smoke shaft and stair pressurization requirements. An existing building which is to be sprinklered throughout shall be exempt from the smoke shaft and stair pressurization requirements under the following conditions: (1) the installation proceeds in conformance with a schedule acceptable to the commissioner, setting forth the sequence and corresponding time for installation in the various locations. On or before September thirteenth, nineteen hundred eighty such a schedule, as well as complete plans of the installation, shall be filed with, and a permit secured from, the commissioner for the phase of the work to be done as required by paragraph two of this subdivision. (2) at least one-third of the total floor area of the building, including but not limited to the entrance lobby, corridors and elevator landing areas, is sprinklered on or before December thirteenth, nineteen hundred eighty-one. (3) at least two-thirds of the total floor area of the building is sprinklered on or before December thirteenth, nineteen hundred eighty-two. (4) the building is sprinklered throughout on or before December thirteenth, nineteen hundred eighty-three. Where compliance with the time requirements of this subdivision would cause undue hardship, the commissioner, with the approval of the fire commissioner, may extend the time for compliance, in accordance with rules and regulations to be promulgated. Before such application for a time extension shall be considered all required applications and plans must be filed and approved, permits obtained and a good faith effort towards completion of the work shall have been made.

NYC Admin. Code § 27-353.1 Smoke protection for elevators and escalators.

§ 27-353.1 Smoke protection for elevators and escalators. (a) Elevators. In existing buildings classified in occupancy group J-1, at every floor above the main entrance floor, all passenger elevators shall open only into elevator vestibules, except for: (1) Such existing buildings which contain spaces classified in occupancy group C or F and have an automatic sprinkler system protecting all spaces (except boiler rooms) not in occupancy group J-1 and all exits and corridors serving such spaces located on or below the lowest floor containing sleeping rooms as well as all storage closets no matter where located, except that storage closets less than seventy-five square feet may, in the alternative, be provided with smoke detectors which shall be of the central supervisory type connected to an approved central station; or (2) Such existing buildings which contain no spaces in occupancy group C or F, and have either: a. An automatic sprinkler system protecting all public areas and storage closets; or b. An automatic sprinkler system protecting all sleeping rooms and storage closets. c. Notwithstanding subparagraphs a and b of this paragraph, storage closets less than seventy-five square feet may be provided with smoke detectors of the central supervisory type connected to an approved central station. d. Notwithstanding any other provision of this code, the sprinklers serving the storage closets may be connected with the domestic water supply. (b) Escalators. In buildings and existing buildings classified in occupancy group J-1, fire protection for escalators shall be provided by any one of the following methods: (1) Enclosure in accordance with sections 27-375 and 27-378 if escalator is used as an exit; or (2) Automatic rolling shutters in accordance with reference standard RS 18-1; or (3) Kiosks in accordance with reference standard RS 18-1; or (4) Where the building section is fully protected by a supervised automatic sprinkler system and the escalator sprinklers are spaced to protect exposed sides of the escalator opening, a noncombustible heat apron constructed to bank heat around the sprinkler heads adjacent to the opening where the bottom edge of the draft curtain is not less than twelve inches below the bottoms of sprinkler heads when heads are in operation, and in no event less than twenty-four inches below the ceiling; or (5) Spray nozzles in accordance with reference standard RS 18-1. (c) The requirements of this subdivision shall be complied with on or before April first, nineteen hundred eighty-seven.

NYC Admin. Code § 27-353.2 Smoke protection for elevators in E occupancies.

§ 27-353.2 Smoke protection for elevators in E occupancies. For an elevator in a high rise building where such elevator serves four or more stories that contain space classified in occupancy Group E (office space), inclusive of any lobby or entry level, such elevator shall meet the following requirements at every level served by such elevator (i) for such buildings erected pursuant to new building applications filed on or after the effective date of this section, or (ii) where two or more new elevator shafts are installed in such buildings in existence on the effective date of this section: (a) Elevator vestibule required. 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. (b) Permitted penetrations. Penetrations in addition to those permitted in section 27-353.3 (smoke barrier) shall be provided with smoke dampers as defined in reference standard RS 13-1, except that a package pass through or communication opening not exceeding one square foot in area need not be provided with smoke dampers. (c) Access to exits. 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. (d) On floors with a floor area of less than twenty-five hundred square feet, the commissioner may accept an alternative design or construction method that accomplishes the purposes of this section, or, if the commissioner determines that compliance with this section is impracticable in whole or in part, the commissioner may authorize an exemption from the requirements of this section.

NYC Admin. Code § 27-353.3 Smoke barrier.

§ 27-353.3 Smoke barrier. A smoke barrier may or may not have a fire resistance rating. Smoke barriers may have openings that are protected by automatic closing devices, adequate to inhibit movement of smoke through the opening. The smoke barrier may be constructed of heat-strengthened or tempered glazing or the equivalent and protected by sprinkler heads constructed in accordance with subchapter seventeen of this chapter and installed a maximum of six feet (6'-0") on center on each side of the barrier. If the smoke barrier is constructed of glass, the portions of the smoke barrier located within two feet of the door opening and within five feet of the floor shall be constructed of tempered glass. Glass panels having an area in excess of nine square feet with the bottom edge less than eighteen inches above the floor shall likewise be constructed of tempered glass. Portions of glass smoke barriers shall be marked where required in accordance with the rules of the board of standards and appeals.

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/0-0-0-49213Fetched: 10/24/2026