N.Y.C. Admin. Code § BC 403: Section BC 403: High-Rise Buildings

403.1 Applicability.

High-rise buildings shall comply with Sections 403.2 through 403.8.

Exception: The provisions of Sections 403.2 through 403.8 shall not apply to the following buildings and structures:

1. Air traffic control towers in accordance with Section 412.3.

2. Buildings occupied entirely by Group R-3 classification.

3. Open parking garages in accordance with Section 406.5.

4. The portion of a building containing a Group A-5 occupancy in accordance with Section 303.6.

5. Special industrial occupancies in accordance with Section 503.1.1.

6. Buildings with:

6.1. A Group H-1 occupancy;

6.2. A Group H-2 occupancy in accordance with Section 415.8, 415.9.2, 415.9.3 or 426.1; or

6.3. A Group H-3 occupancy in accordance with Section 415.8.

403.2 Construction.

The construction of high-rise buildings shall comply with the provisions of Sections 403.2.1 through 403.2.4.

403.2.1 Types of construction.

The following modifications to the minimum fire-resistance rating of the building elements in Table 601 shall be as follows:

1. High rise buildings 420 feet (128 m) or greater in building height shall be constructed of Type IA construction.

2. For high rise buildings not greater than 420 feet (128 m) in building height, and constructed to meet the fire-resistance rating requirements of Type IB or IIA construction, the required fire-resistance rating of columns supporting floors shall be constructed to meet Type IA construction.

403.2.2 Seismic considerations.

For seismic considerations, see Chapter 16.

403.2.3 Structural integrity of interior exit stairways and elevator hoistway enclosures.

For all high-rise buildings, exit enclosures for interior exit stairways and elevator hoistway enclosures shall comply with Sections 403.2.3.1 through 403.2.3.4.

Exception: Where fire-resistance rating is not required by this code for the enclosure or portions thereof.

403.2.3.1 Wall assembly.

The wall assemblies making up the enclosures for interior exit stairways and elevator hoistway enclosures shall meet or exceed Soft Body Impact Classification Level 2 as measured by the test method described in ASTM C 1629 / C 1629M.

403.2.3.2 Wall assembly materials.

The face of the wall assemblies making up the enclosures for interior exit stairways and elevator hoistway enclosures that are not exposed to the interior of the enclosures for interior exit stairways or elevator hoistway enclosure shall be constructed in accordance with one of the following methods:

1. The wall assembly shall incorporate no fewer than two layers of impact-resistant construction board each of which meets or exceeds Hard Body Impact Classification Level 2 as measured by the test method described in ASTM C 1629 / C 1629M.

2. The wall assembly shall incorporate no fewer than one layer of impact-resistant construction material that meets or exceeds Hard Body Impact Classification Level 3 as measured by the test method described in ASTM C 1629 / C 1629M.

3. The wall assembly incorporates multiple layers of any material, tested in tandem, that meets or exceeds Hard Body Impact Classification Level 3 as measured by the test method described in ASTM C 1629 / C 1629M.

403.2.3.3 Concrete and masonry walls.

Concrete or masonry walls shall be deemed to satisfy the requirements of Sections 403.2.3.1 and 403.2.3.2.

403.2.3.4 Other wall assemblies.

Any other wall assembly that provides impact resistance equivalent to that required by Sections 403.2.3.1 and 403.2.3.2 for Hard Body Impact Classification Level 3, as measured by the test method described in ASTM C 1629 / C 1629M, shall be permitted.

403.2.4 Sprayed fire-resistant materials (SFRM).

The bond strength of the SFRM installed throughout the building shall be in accordance with Table 403.2.4.

Table 403.2.4 Minimum Bond Strength

Height of Building

a

SFRM Minimum Bond Strength 

Up to 420 feet

430 psf

Greater than 420 feet

1,000 psf

For SI: 1 foot = 304.8 mm, 1 pound per square foot (psf) = 0.0479 kW/m

2

.

a. Above the lowest level of fire department vehicle access.

403.3 Automatic sprinkler system.

Buildings and structures shall be equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 and a secondary water supply where required by Section 403.3.3.

403.3.1 Number of sprinkler risers and system design.

Each sprinkler system zone in buildings that are more than 300 feet (91 440 mm) in building height shall be supplied by no fewer than two risers. Each riser shall supply sprinklers on alternate floors. If more than two risers are provided for a zone, sprinklers on adjacent floors shall not be supplied from the same riser.

403.3.1.1 Riser location.

Sprinkler risers shall be placed in interior exit stairways and ramps that are remotely located in accordance with Section 1007.1.

403.3.2 Water supply to required fire pumps.

Required fire pumps shall be provided with water supplies in accordance with Section 905.2 and NFPA 14 as modified by Appendix Q of this code.

403.3.3 Secondary on-site water supply.

A secondary on-site water supply equal to the hydraulically calculated sprinkler demand, including the hose stream requirement, shall be provided for high-rise buildings in Seismic Design Category C or D as determined by this code, and in any high-rise building with occupied floors located more than 500 feet (152 m) above the lowest level of fire department vehicle access. The secondary on-site water supply shall have a duration of not less than 30 minutes as determined by the occupancy hazard classification in accordance with NFPA 13 as modified by Appendix Q of this code.

403.3.4 Fire pump room.

Fire pumps shall be located in rooms protected in accordance with Section 913.2.1.

403.4 Emergency systems.

The detection, alarm and emergency systems of high-rise buildings shall comply with Sections 403.4.1 through 403.4.8.

403.4.1 Smoke detection.

Smoke detection shall be provided in accordance with Section 907.2.13.1.

403.4.2 Fire alarm systems.

A fire alarm system shall be provided in accordance with Section 907.2.13.

403.4.3 Standpipe system.

A high-rise building shall be equipped with a standpipe system as required by Section 905.3.

403.4.4 Emergency voice/alarm communication system.

An emergency voice/alarm communication system shall be provided in accordance with Section 907.5.2.2.

403.4.5 Emergency responder radio coverage.

Emergency responder radio coverage shall be provided in accordance with the New York City Fire Code and Section 907.2.13.2 of this code.

403.4.6 Fire command.

A fire command center complying with Section 911 shall be provided in a location approved by the Fire Department.

403.4.7 Post-fire smoke purge.

A post-fire smoke purge system shall be installed in accordance with Section 917.

403.4.8 Standby and emergency power.

A standby power system complying with Section 2702 and Section 3003 shall be provided for the standby power loads specified in Section 403.4.8.3. An emergency power system complying with Section 2702 shall be provided for the emergency power loads specified in Section 403.4.8.4.

403.4.8.1 Equipment room.

If the standby or emergency power system includes a generator set inside a building, the system shall be located in a separate room in accordance with Section 2702.1.2.2.

403.4.8.2 Fuel line piping protection.

Fuel lines supplying a generator set inside a building shall comply with Section 1305.9 of the New York City Mechanical Code.

403.4.8.3 Standby power systems.

A standby power system complying with Section 2702 shall be provided for standby power loads specified in Sections 403.4.8.3.1 and 403.4.8.3.2. Fuel sources for generators shall be in accordance with Section 2702.1.1.

403.4.8.3.1 Standby power loads in occupancies other than Group R-2.

In buildings of any occupancy group other than Group R-2, the following are classified as standby power loads:

1. Power and lighting for fire command center required by Section 403.4.6;

2. Ventilation and automatic fire detection equipment for smokeproof enclosures;

3. Elevators, in accordance with Section 3003; and

4. Stair pressurization systems when provided.

403.4.8.3.2 Standby power loads in Group R-2 occupancies.

Group R-2 occupancies in buildings greater than 125 feet (38 100 mm) in height shall be required to provide a standby power system to support the following loads:

1. Power and lighting for fire command center required by Section 403.4.6;

2. Ventilation and automatic fire detection equipment for smokeproof enclosures;

3. At least one elevator serving all floors, or one elevator per bank where different banks serve different portions of the building; and

4. Stair pressurization systems when provided.

403.4.8.4 Emergency power systems.

An emergency power system complying with Section 2702 shall be provided for emergency power loads specified in Sections 403.4.8.4.1 and 403.4.8.4.3. Fuel sources for generators shall be in accordance with Section 2702.1.1.

403.4.8.4.1 Emergency power loads in occupancies other than Group R-2.

In buildings of any occupancy group other than Group R-2, the following are classified as emergency power loads:

1. Exit signs and means of egress illumination required by Chapter 10;

2. Elevator car lighting;

3. Emergency voice/alarm communications systems, including Fire Department in-building Auxiliary Radio Communication systems (ARCs);

4. Automatic fire detection systems;

5. Fire alarm systems; and

6. Electrically powered fire pumps, including manual fire pumps, automatic fire pumps, and sprinkler booster pumps.

403.4.8.4.2 Emergency power loads in Group R-2 occupancies.

Group R-2 occupancies in buildings greater than 125 feet (38 100 mm) in height shall be required to provide an emergency power system to support the following loads:

1. Exit signs and means of egress illumination required by Chapter 10;

2. Emergency voice communications systems, including Fire Department in-building Auxiliary Radio Communication systems (ARCs); and

3. Electrically powered fire pumps, unless electrical power to the motor is taken ahead of the main from the street side of the house service switch.

403.4.8.4.3 Emergency power loads in Group R-2 occupancies 125 feet or less in height.

Group R-2 occupancies in buildings 125 feet (38 100 mm) or less in height shall be required to provide an emergency power system to support the following loads:

1. Emergency voice communications systems in buildings containing Group R-2 occupancies in accordance with Section 907.5.2.2 of this code, or where otherwise provided. Batteries in accordance with the New York City Electrical Code are permitted to serve as the secondary power supply for such systems.

2. Fire Department in-building Auxiliary Radio Communication systems (ARCs) in buildings containing Group R-2 occupancies in accordance with Section 916.3 of this code, or where otherwise provided. Batteries in accordance with the New York City Electrical Code are permitted to serve as the secondary power supply for such systems.

403.5 Means of egress and evacuation.

The means of egress in high-rise buildings shall comply with Sections 403.5.1 through 403.5.6.

403.5.1 Remoteness of interior exit stairways.

Required interior exit stairways shall be separated by a distance not less than 30 feet (9144 mm) or not less than 1/4 of the length of the maximum overall diagonal dimension of the building or area to be served, whichever is less. The distance shall be measured in a straight line between the nearest points of the enclosure surrounding the interior exit stairways. In buildings with three or more interior exit stairways, no fewer than two of the interior exit stairways shall comply with this section. Stairs sharing any common wall, floors, ceilings, scissor stair assemblies, or other enclosures shall be counted as one interior exit stairway.

Exception: Group R-2 occupancies.

403.5.2 Additional exit stairway.

For buildings other than Group R-2 that are more than 420 feet (128 m) in building height, one additional exit stairway meeting the requirements of Sections 1011 and 1023 shall be provided in addition to the minimum number of exits required by Section 1006.3. The total width of any combination of remaining exit stairways with one exit stairway removed shall not be less than the total width required by Section 1005.1. Stairs sharing any common wall, floors, ceilings, scissor stair assemblies, or other enclosures shall not be considered the additional exit stairway required by this section.

Exceptions: An additional exit stairway shall not be required to be installed in any of the following instances:

1. In buildings where all passenger elevators for general public use and all other elevators used for occupant self-evacuation comply with Sections 3008.1 through 3008.11;

2. In buildings where all of the following conditions are met:

2.1. The commissioner has approved a timed egress analysis establishing the egress time it would take for a full building evacuation, utilizing the stairs required by Section 1006 and the additional stair that would have been required pursuant to Section 403.5.2;

2.2. The commissioner has approved a timed egress analysis establishing the egress time it would take for a full building evacuation, utilizing the combination of the stairs required by Section 1006 and elevators used for occupant self-evacuation as follows:

2.2.1. Such analysis need only utilize a number of designated elevators designed for occupant self-evacuation necessary to demonstrate an evacuation time that is less than the time established in Exception 2.1; and

2.2.2. Every bank of passenger elevators for general public use shall be served by at least one such designated elevator;

2.3. All elevators in the building that either are passenger elevators for general public use or are used for occupant self-evacuation shall comply with Sections 3008.1 through 3008.11. However, the standby power generating equipment required by Section 3008.9 need only be sized to satisfy the loads required to simultaneously operate those elevators identified in the timed egress analysis described in Exception 2.2.

The minimum number of exits required by Section 1006 are all at least 25 percent wider than the exit width required by Chapter 10. The increase in the stair width shall not be utilized in the timed egress analyses required by Exceptions 2.1 and 2.2.

403.5.3 Stairway door operation.

Doors opening into interior stair enclosures shall not be locked from either side. However, a door locked from the stair side may be permitted provided that such door is equipped with an automatic fail safe system for opening in the event of the activation of any automatic fire detection system, or when any elevator recall is activated, or when any signal is received from the fire command center. Such door shall be deemed as openable from the stair side. Stair reentry signs shall be posted throughout the stairway indicating that reentry is provided only during fire emergencies. Such signs shall be in accordance with Section 1031.4.2.

Exception: In schools classified as Group E occupancies that require "lockdown drills" as per Section 807 of the New York State Education Law, stairway egress doors from occupied spaces are permitted to be locked from the side opposite the egress side for the duration of the lockdown drill, provided they are openable from the occupied side for egress and are unlocked upon directions from the school administrative personnel following the completion of the lockdown drill.

403.5.3.1 Stairway communication system.

A telephone or other two-way communications system connected to an approved constantly attended station shall be provided at not less than every fifth floor in each stairway where the doors to the stairway are locked in accordance with Section 403.5.3.

403.5.4 Smokeproof enclosures.

Every required interior exit stairway serving floors more than 75 feet (22 860 mm) above the lowest level of fire department vehicle access shall comply with Sections 909.20 and 1023.11

Exception: Smokeproof enclosures are not required in occupancy Group R-2 unless provided pursuant to Exception 2 of Section 917.1.

403.5.5 Luminous egress path markings.

Luminous egress path markings shall be provided in accordance with Section 1025 and Appendix S.

Exception: Egress paths serving Group R-2.

403.5.6 Emergency escape and rescue.

Emergency escape and rescue openings specified in Section 1030 are not required.

403.6 Elevators.

Elevator installation and operation in high-rise buildings shall comply with Chapter 30 and Sections 403.6.1 and 403.6.2.

403.6.1 Fire service access elevator.

In buildings with an occupied floor more than 120 feet (36 576 mm) above the lowest level of fire department vehicle access, a minimum of one fire service access elevator shall be provided in accordance with Section 3007.

403.6.2 Occupant evacuation elevators.

Where installed in accordance with Section 3008, passenger elevators for general public use shall be permitted to be used for occupant self-evacuation.

403.6.3 Elevator lobbies.

Elevator lobbies shall be provided in accordance with Sections 3006.1.1 and 3006.1.2.

403.7 Outdoor air intakes.

For high-rise buildings, outdoor air intakes serving spaces above the second story and serving spaces greater than 10,000 square feet (929 m

2

) of floor area shall be located in accordance with Section 401.5 of the New York City Mechanical Code.

Exception: Group R-2 occupancy.

403.8 Open web steel joists.

The use of open web steel joists shall be prohibited in high-rise buildings until the commissioner promulgates rules establishing minimum acceptable fireproofing methods.