2. Fire Prevention

Seismic Load -

1. Buildings undergo dynamic motion during the earthquake. 2. The building is subjected to inertia forces that act in the opposite direction to the acceleration of earthquake excitations. 3. These inertia forces called seismically loads are usually dealt with by assuming forces external to the building.

Sesmic load [source- google images] Seismic loads, are usually dealt with by assuming forces external to the building

Wind Loads –

1. Thermal loads (temperature changes leading to thermal expansion) 2. The lateral pressure of soil, groundwater or bulk materials. 3. Wind load has the ability to bring a building to sway. 4. Wind velocity increases with the increase in height.

Wind load [source- google images]

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Wind Loads Wind Turbulence -

1. When any moving air mass meets an obstruction, such as building, it responds like any fluids by moving to each side, then rejoining the major airflow. 2. The Ventury effect is one type of turbulent wind action. Turbulence develops as the moving air mass is funneled through the narrow space between two tall buildings. The corresponding wind velocity in this space exceeds the wind velocity of the major airflow.

Core -

1. The core is one of the most important structural and functional elements of the highrise building 2. The core of a building is the area reserved for elevators’ stairs, mechanical equipment and the vertical shafts that are necessary for ducts, pipes and wires 3. Its wall is also the most common location for the vertical wind bracing. 4, The placement of the service core stems from four generic types which are: Central core

Split-core End core Atrium core

Typology of service core [source- google images]

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2.3 Servicses:

1.Fire Fighting Systems -

1. The fire appears to be by far the most common extreme situation that will cause damage in structures, it must be a primary consideration in the design process. 2.‘The characteristic feature of a fire such as temperature and duration can be estimated from a knowledge of the important parameters involved, particularly the quality and nature of combustible material present, the possibility and extent of ventilation and the geometric and thermal properties of the fire compartment involved.

3. Once thetemperatures atthe varioussurfaces have been determined,from tegastemperaturecure, it ispossible toestimate heat flow throughtheinsulation andstructuralmembers.

4. The parameters that govern the approach are stochastic in nature, and the results of any calculation can be given only in probabilistic terms. The aim should be to achieve a homogeneous design in which the risks due to the different extreme situations are comparable.

Location of a stand pipe in building [source- google images]

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Fire zone Demarcation For coding, city or area under jurisdiction or authority is demarcated into distinct zones, based on fire hazard inherent in the building and structures according to occupancy. Group A or Residential buildings are comprised in Fire Zone 1.

2. Fire Prevention -

Every building shall be so constructed, equipped, maintained and operated as to avoid undue danger to the life and safety of the occupants from fire, smoke, fumes or panic during the period necessary for escape. 3. Fire Safety and Services 1. Electrical and ventilation services- Electrical installations, air-conditioning and ventilation should be installed and maintained to minimize the danger of the spread of fire, smoke or fumes from one floor to other. 2. Air-conditions and ventilation should be provided with manual and automatic control to shut automatically in case of fire and stop it from spreading. 3. Smoke Venting-Smoke venting facilities should be provided for ensuring safe exit with automatic and manual control both.

4. Openings and Fire Safety 1. Every wall opening should be protected with a fire-resistant door with a fire rating of min 2 h.

2. Openings in-wall or floor for the passage of services should be enclosed by shaft or duct with a fire rating of 2 hours. 3. Every vertical opening should be enclosed or protected to ensure the escape of its occupants and limit the damage to the building. 5. Glazing 1. Wired glasses should have a minimum 1 hour fire-resistance rating. 2. The sashes and frame should be entirely made of iron stainless steel or other suitable metal.

3. Electro copper glazing, casement, the skylight will also follow the same criteria. 4. The glass used for the facade of a high-rise building should have a minimum of 1-hour fire-resistance rating.

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5. Louvres should have a minimum fire-resistance rating of hour. 6. Occupancy Wise Requirements Design Precautions 1. Every individual living unit covered by occupancy sub-division A-4 shall comply with the requirement for occupancy subdivision A-2 in respect of exits. 2. More than two rooms, every occupied room, excluding areas used solely for storage shall have at least two means of exits, at least one of which shall be a door or a stairway providing a means of unobstructed travel to the outside of the building or street or grade level.

3. A common path of travel may be permitted for the first 6 m (that is a dead-end corridor up to 6 m long may be permitted). 4. No room or space shall be occupied which is accessible only by a ladder, folding stairs or through a trap door. 5. Any part of building lower than the grade level or street shall have direct accessibility from outside.

6. At least half of required exits shall discharge directly to the outside of the buildings, any other exit shall be the same as required for hotels.

7. Life Safety General Exit Requirement -

1. Every building meant for human occupancy should be provided with exits sufficient to permit the safe escape of its occupants, in case of fire, or emergency. 2. An exit can be • A doorway or a corridor • The passageway(s) to internal or external staircase/verandah /terrace, which has access to the street, or to the roof or a refuge area. • A horizontal exit leading to an adjoining building at the same level. Lifts and escalators shall not be considered as exits.

1. All exits should be free of obstructions and well equipped to be used in case of fire or other emergencies. 2. Exits should be:

• Clearly visible • Illuminated to the value of 1 ft candle

• Should provide continuous means of escape to the exterior • The route to reach the exit shall be clearly marked

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• Signs posted to guide the occupants of the floor concerned. 8. Arrangements of Exit 1. Total time taken to evacuate a floor by all its occupants should not exceed 2 min. The travel distance to an exit from the dead-end of a corridor should not be more than 22.5-

30 m. (in case of fully sprinklered building, the travel distance can be increased by 50%). 2. In case of more than one exit, it should be placed as remote from each other as possible and should have direct access in separate directions from any point. 3. The internal walls of staircase enclosures should be of brickwork or reinforced

concrete or any other material of construction with a minimum of 2 h rating. They should be of enclosed type. 4. At least one of them should be on the external walls and should open directly to an open space of safety. 5. All corridors (minimum 1000mm) and staircase lobbies should be adequately ventilated.

9. Fire exit exit doorways 1. It should open into an enclosed stairway or any exit. 2. The exit width should not be less than 1000 mm.

3. It should open outward. 4. It should have a landing before the flight of stairs, equal to the width of the door. 5. It should be openable from the side which they serve.

Exit doorways (source: google images)

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Refuge Area –Refuge area shall be provided in buildings of height more than 24 m. Refuge area provided shall be planned to accommodate the occupants of two consecutive floors (this shall consider occupants of the floor where refuge is provided and occupants of floor above) by considering area of 0.3 m2 per person for the calculated number of occupants and shall include additionally to accommodate one wheelchair space of an area of 0.9 m2 for every 200 occupants, portion thereof, based on the occupant load served by the area of refuge or a minimum of 15 m2, whichever is higher, shall be provided as under: 1. The refuge area shall be provided on the periphery of the floor & open to air at least on one side protected with suitable railing. 2. For floors above 24m & up to 39m one refuge area on the floor immediately above 24m.

3. For floors above 39m, one refuge area on the floor immediately above 39m & so on after 15m refuge area shall be provided. SA BUILDING-A REFUGE FLOOR P Figure 43. Ref. As per section 8.12.3 on part IV of NBC

Ramps 1. They should comply with all the requirements for staircase regarding enclosure, capacity and limiting dimensions. 2. The slope of the ramp should not exceed 1:10. 3. In danger of slipping, non-slipping material should be applied on the surface. Fire Lift -

1. The lift installed to enable fire services personnel to reach different floors with minimum delay, having such features as required following this part. 2. High buildings can be provided with a fire lift with a minimum capacity of 8 passengers and fully automated with emergency switch on the ground level. 3. In case of fire, the only fireman should operate the fire lift. 4. Should be equipped with intercommunication equipment.

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5. Its position and number can be determined by considering population, floor area, compartmentation 6. A sign indicates that is a Fireman's elevator. That is also a normal Kone passenger elevator when it not in fire service mode.

Emergency Lighting A complete but discrete emergency lighting installation from the standby power source to the emergency lighting lamp(s), for example, self-contained emergency luminaire or a circuit from central battery generator connected through wiring to several escape luminaries.

Escape Lighting That part of emergency lighting which is provided to ensure that the escape route is illuminated at all material times, for example, at all times when persons are on the premises, or at times the main lighting is not available, either for the whole building or for the escape routes. Fire Protection -

a) Fire Extinguishers/Fixed Fire Fighting Installation 1. All buildings depending upon the occupancy use and height should be protected by fire extinguishers, wet riser, down-comer, automatic sprinkler installation, high medium velocity water spray, water storage tanks, fire pumps etc., according to the provision. 2. Generally used firefighting types of equipment in GROUP A buildings: 3. Fire Extinguisher, Hose Reel. Wet Riser, Down Comer, Hydrant, Pump, Automatic Sprinkler System, Underground Static Water-Storage Tank, Illuminated Exit-Way Marking Signs, Automatic/ Manually Operate Fire Detection and Alarm System. Fire Fighting Requirements in Residential Buildings 1. It is required to be installed in the basement if the area of basement exceeds 200 sqm. 2. Additional value given in parenthesis shall be added if basement area exceeds 200

sqm. 3. If the basement provided is used for car parking and the area there of exceeds 750 sqm then the sprinklers shall be fed water from both underground static water storage tank and terrace tank to be installed in the entire building.

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