13-56-260 Mixed occupancy – Applicable provisions.

   When a building is occupied by two or more occupancies not included in one classification, the provisions of this Code applying to each use shall apply to such parts of the building as come within that classification.

(Prior code § 48-12.3)

13-56-270 Mixed occupancy – Height and area limitations.

   Height and area limitations in buildings of mixed occupancy shall comply with the requirements of Section 13-48-100.

(Prior code § 48-12.4)

13-56-280 Mixed occupancy – Fire-resistive separations required.

   Each occupancy in a building of mixed occupancy shall be separated horizontally and vertically from any adjoining occupancy by construction materials providing fire resistance as established in Table 13-56-280 as set out in this section. Separation between Type III schools and A, B, C-1, C-2, and E occupancies, except day care centers with children less than two years of age, may be reduced to one hour. Separation between Type III schools with children less than two years of age and A, B, C-2, E and F occupancies may be reduced to two hours.

   Separation in buildings of mixed occupancies may be reduced by one hour from the fire resistance requirements as established in Table 13-56-280 as set out in this section when the building is equipped throughout with an approved automatic sprinkler system which is supervised except that separations between day care centers with children less than two years of age and A, B, C, C-1, C-2, E and F occupancies shall not be reduced to less than two hours.

(Prior code § 48-12.5; Amend Coun. J. 9-13-89, p. 4604; Amend Coun. J. 7-14-93, p. 35324; Amend Coun. J. 10-30-96, p. 31214)

Table 13-56-280 REQUIRED SEPARATIONS IN BUILDINGS OF MIXED OCCUPANCY Fire Resistive Ratings in Hours
Occupancy Classification		A	B	C-1	C-2	C-3	D	E	F	G	H-1 H-2	H-3	I
A.	Residential		3	4	2	4	4	1(d)	1	4	4	4	(b)
B.	Institutional	3		4	4	3	4	4	4(c)	(b)	4(c)	4(c)	(b)
C-1.	Large assembly	4	4		4	4	4	4	4	4(c)	4(c)	4(c)	(b)
C-2.	Small assembly	2	4	4		4	2	2(d)	2	4	4	4	(b)
C-3.	Schools	4	3	4	4	(e)	4	2(d)	4	4(c)	4(c)	4(c)	(b)
D.	Open air assembly	4	4	4	2	4		4	4	4	4	4	(b)
E.	Business	1(d)	4	4	2(d)	2(d)	4(d)	(d)	(a)(d)	(a)(d)	(a)(d)	2(d)	4
F.	Mercantile	1	4(c)	4	2	4	4	(a)		3	(a)	3	(b)
G.	Industrial	4	(b)	4(c)	4	4(c)	4	(a)(d)	3		(a)	4	4
H-1 & H-2.	Storage	4	4(c)	4(c)	4	4(c)	4	(a)(d)	(a)	(a)		4	4
H-3.	Garages	4	4(c)	4(c)	4	(c)	4	2(d)	3	4	4		4
I.	Hazardous use	(b)	(b)	(b)	(b)	(b)	(b)	4(d)	(b)	4	4	4
(a)   No special separation required. (b)   Mixed occupancy not permitted. (c)   Unpierced separations. (d)   A technology center shall have a minimum two-hour separation from all other occupancies including other business occupancies, regardless whether the subject building is protected by a sprinkler system. (e)   For trade or technical schools, shop portions of schools may be built to comply with requirements for industrial buildings, but shall have four-hour fire separations with double Class A fire doors between shop portions and academic portions of buildings.

 

(Added Coun. J. 6-28-00, p. 36679, § 5)

13-56-290 Separation from public spaces below grade.

   (a)   The interior of any building which adjoins a subway or other public space below grade not open to the sky, shall be separated from subway or other public space by walls or floors of solid masonry or reinforced concrete, or equal with a fire-resistive rating of not less than four hours.

   (b)   Every opening through a wall, required by this section to be used as an exit, shall be protected by a labeled outswinging Class A fire door. Such doors shall be equipped with approved panic hardware and may be single or pairs. Every other opening through such wall, not required as an exit shall be protected with a Class A fire door.

   (c)   No wall used in a separation required by this section shall be located more than twenty feet back from the subway or other public space. Show windows and display spaces may be located on the public side of such separating wall, but there shall not be more than one door opening into each show window or display space.

   (d)   Nothing in this section shall be construed to prevent the entire space under any building or any portion of such space, or any passage through a building from being used as a right-of-way or switching space for railroads or public carriers; provided, however, that such spaces or passages shall not be designed or used as a public thoroughfare nor as a parking space for motor vehicles where such use is prohibited by other sections of this Code; and provided further, that such space is separated from the interior and adjacent parts of the building as required by this section for subways.

(Prior code § 48-12.6)

13-56-300 Occupancy content determination.

   When the requirements of this Code are related to the maximum number of persons occupying a space or building such occupancy content shall be determined as provided in Sections 13-56-310 and 13-56-320.

(Prior code § 48-13)

13-56-310 Assembly units and open air assembly units – Occupancy content.

   For assembly units and open air assembly units, the occupancy content shall be based on the capacity of the rooms or spaces used for assembly purposes and shall be determined as follows:

   (a)   In rooms or spaces with fixed seating, the occupancy content shall be the actual number of seats provided. When no divisions between seats are provided, fixed seating shall be computed at 18 inches per person.

   (b)   In rooms or spaces without fixed seating, the occupancy content shall be determined by the dividing of the net floor area (excluding the areas occupied by elevators, toilet rooms, stairways, other shaft enclosures, and by permanent fixtures such as bowling alleys, bars, cigar counters, exit facilities, entrance vestibules, lunch counters and serving spaces for same, etc.) by the floor area per person established in the following table:

Occupancy   Floor Area Per Person

   (1)   School classrooms (other than open plan schools) and recreation rooms   20 sq. ft.

   (2)   Open plan schools, school laboratories and shops   30 sq. ft.

   (3)   Museums, libraries and similar uses   20 sq. ft.

   (4)   Restaurants   15 sq. ft.

   (5)   Other assembly uses   6 sq. ft.

   (6)   Exhibition areas   20 sq. ft.

   (7)   Day care center – Class I   35 sq. ft.

(Prior code § 48-13.1)

13-56-320 Other occupancies – Occupancy contents.

   In occupancies, other than assembly units, the occupancy contents shall be determined by dividing the net floor area within the perimeter of the space or building not including elevators, stairways, or other shaft enclosures by the floor area per person established in the following table:

Table 13-56-320
Other Occupancies, Occupant Load – Floor Area Per Person

Occupancy

   Residential units   125

   Institutional units (See Ch. 53-7(a))   150

   Business units   100(a)

   Mercantile units

      First floor   30

      Basement sales floor   30

      Other floors   60

   Industrial units

      Power plants   400

      Other industrial units   100

   Storage units   300

Note:

   (a)   In a building in which one or more technology centers are located, occupancy of the entire floor and the capacity of fire stairs shall be determined in accordance with the “net floor area” defined in Section 13-56-320. For individual tenant spaces qualifying as technology centers, the occupant load shall be determined on the basis of the “special (technology center) net floor” area which, in addition to the exclusion listed in Section 13-56-320, also excludes stationary computer equipment and computer machinery.

(Prior code § 48-13.2; Amend Coun. J. 6-28-00, p. 36679, § 6)