§ 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.