1. OBJECTIVES AND STRATEGIES OF THE FIRE PROTECTION DESIGN This report describes the design parameters, system requirements of fire protection system for mixed occupancy (Assembly + Business) building Group D-6 & Group E-5 Office building height is more than 30 meter. The objective of this report is to design a fire protection system as per National Building Code, NBC 2005, Part IV of Fire & Life Safety. Following are the systems proposed as per NBC & Local Fire Authority: Centralized Fire Water Tank and Pump room. Pumps and Pump room. Multi Jet Water curtain nozzles. Wet riser cum down comer system. External & Internal Fire Hydrants. Automatic sprinkler system. Addressable Fire detection & Alarm system. Public address system Extinguisher system. 2. DESIGN CRITERIA AND DESCRIPTION Fire protection system shall be designed and installed as per NBC standards & Local authority Requirements. 3. FIRE SUPRESSION SYSTEM: Fire suppression system Office building is classified as follows; Hydrant system (Internal & External). Automatic sprinkler system. Fire pumps. Fire water storage tanks. Fire extinguisher system. 4. HYDRANT SYSTEM (INTERNAL & EXTERNAL) Water supply for hydrant system (Internal & External) is required to be capable of providing the water pressure and flow characteristics required by systems being served. External yard hydrants near to the face of the building with maximum spacing of 45mts between hydrant points. Internal fire hydrant station consisting of landing valve and swinging type hose reel
shall be provided at; - All floors at every 1000sq.m interval at each floor landing near the staircase. 4.1 PROPOSED DESIGN: Fire Hydrant system (Internal & External): System shall be hydraulically designed to provide water flow at a minimum pressure of 3.5bars at the outlet of remotest hydrant valve. Each internal hydrant station shall comprise of double headed landing valve, swinging type hose reel and other equipment. Internal hydrants shall be provided for every 1000sqm floor area at each floor landing near the staircase. The minimum flow rate of 2850lpm. Internal hose connection and hose station shall be unobstructed and shall be located near the staircase, opening to the common area. The shaft size shall be of 0.9mts x 1.2mts. The hydrant riser shall be terminated with air release valve at the highest point to release the trapped air in the pipe network. The External hydrants shall be provided near the face of the building with the maximum spacing of 45 mts between two external hydrants. Four way Fire Brigade inlet connection at ground level is provided at suitable location to fill the rising mains of hydrant system, in case of failure of pumps. Water storage capacity: Combined water reservoir with minimum effective capacity of 2,00,000 liters shall be provided to meet the minimum requirement of local authority. 4.2 AUTOMATIC SPRINKLER SYSTEM: - The purpose of automatic sprinkler system is to control the growth and spread of fire to provide increased protection to occupants and the building structure. Code Requirements As per NBC- building has been classified, under group E-5 & group D-6 The water supply shall be capable of providing the system demand. Requirements Sprinkler system shall be providing at all Car parking floors. System shall consist with Sprinkler risers, piping network with one layer of sprinkler piping, Sprinkler control valve, Floor control valves and Sprinklers of suitable type. All sprinklers are 68 deg. temperature rating, conventional standard response pendant type for office areas and upright type for car parking areas as suitable / required at site. The Sprinklers are designed to cover 9 to 12 sq.m each and design density of water shall be as per NBC. Note: service rooms like Electrical, D.G. room, AHU room, Toilets, staircases, service shafts and BMS rooms if any are not provided with sprinklers.
The sprinkler mains at each floor level consisting with stop valves & Flow switches, which will transfer audio / visual indications to Fire alarm panel in case of water flow in the pipes. 4.3 Proposed Design The sprinkler system shall be hydraulically designed in accordance with the above requirement. The sprinklers in the buildings shall be fed from separate sprinkler riser located in the landing of the staircases. Each floor shall be considered as separate zone to be annunciate separately at Fire control room. The sprinklers piping network at each floor shall be provide with suitable size of butterfly valve, flow switch and test drain assembly. Isolation control valve (ICV) shall be provided for sprinkler system at suitable location, for alarming in case of fire. 5. AUTOMATIC WATER CURTAIN SYSTEM: Proposed to provide automatic water curtain Multi jet spray nozzles in car parking. The proposed deign is with compartmentalizing in each Floor Open type nozzle with K factor 30 as per the design density 6. FIRE PUMPS: Separate electrical driven fire pumps for hydrant & sprinkler system and common jockey pump and Diesel engine driven pump used for hydrant and sprinkler system. However the diesel engine driven for both the system shall be common. The electrical pump shall be of 2850lpm@142M head. The minimum pressure required at the farthest and remotest hydrant valve is 3.5bars and pump head is calculated accordingly. Common jockey pump for both the systems shall be of 180lpm@142M head Common stand by diesel engine driven pumps for both the systems shall be of 2850lpm@142M head. The jockey pump shut down shall be automatic, whereas the main pumps and the diesel engine for both the system shall have manual shut down. Fire pump test connection with flow measuring station shall be provided with piping to re-circulate the pump's discharge to water supply tank or to the pump suction. Following is the configuration of fire pumps proposed; a) One Electrical driven pump for Hydrant system b) One Electrical driven pump for Sprinkler system c) One common stand by diesel driven pump for hydrant & sprinkler system d) One common jockey pump for hydrant & sprinkler system e) One Booster pump at terrace level. (As per Local authority s requirement)
6.1 SYSTEM OPERATION: When the sprinkler head, hydrant valve or hose reel opens, the pressure drop in respective piping network which will be sensed by pressure switches installed on delivery header of pumping system. This in turn switches on the respective jockey pump automatically to meet the water requirement. In case of further drop, the respective system main pump will start automatically to meet the water requirement. The jockey pump will start and shut down automatically as per pressure gauge settings, whereas the main pumps of both the systems and the diesel engine driven pump will start automatically but shut down has to be done manually. 6.2. Proposed Design Hand held fire extinguishers shall be located so that the maximum travel distance is not more than 23mtrs and shall be located adjacent to fire hose reel cabinet. The fire extinguishers are designed based on the requirement of Local authority. Portable fire extinguishers are provided at the locations mentioned below; Dry chemical powder type extinguisher 6kg ABC type, conforming to IS: 2171 provided near; a) Car parking areas (as per Local authority s one for every 8 car parks) b) In all plant rooms, laundry, kitchens, pantry, computer room, offices, cleaners room, maintenance store, service store, Main switch board room, transformer room, generator room, pump room and lift machine room. Water type fire extinguisher of 9 litres capacity conforming to IS: 940 located near; a) Near staircase landing on every floor. Required as per APFS / Local authority s requirement. Carbon di oxide extinguisher of 4.5 kg conforming to IS: 2878, located in; a) Electrical panel room, lift machine room b) Plant rooms, kitchens, pantry, computer room, offices, cleaners store, maintenance store & service store. Mechanical foam type extinguisher of 9 lts at HSD storage, D.G.Rooms, Fire water pump house and near transformers. 6.3 ADDRESSABLE FIRE DETECTION AND ALARM SYSTEM: - Proposed Design These provisions are intended for early notifications to building occupants of a fire scenario and inform building occupants to evaluate the area accordingly. Voice Evacuation communication system is provided to evacuate the personals at emergency. Individual panels are considered for Common Areas inclusive of Parking and office area respectively. Floor wise isolator module to be considered irrespective of every 20 detectors.
Code requirements Addressable analogue type fire detection and alarm system Designed and installed as per National Building Code. Major Equipment are: Addressable analogue Fire detection & alarm control panel. Multi sensor smoke detectors. Rate of rise heat detectors. Duct sensors. Field devices like modules. (input & output devices) Manual pull stations (break glass type) Electronic Hooters cum strobes Conduits / wiring Detectors are provided in all areas of the building. Manual call points and Hooters are provided at strategic locations. Near exits and other areas such as Lobby & Common corridor nearby fire escape staircase. All detectors and Manual call points looped in class A wiring to Control panel. 6.4 Proposed Design 6.4.1 NBC Part 4 is used as the basis for fire alarm system materials, components and installation methods and the system shall be designed and installed as per National Building code and IS 2189. 6.4.2 The main fire alarm control panel, including annunciation of devices and the voice communication system master controls, is located in the Facility room / Fire Control Room / Fire Command Centre in Basement 1 floor Level. 6.4.3 Manual call points shall be provided outside each door to all exit stairs, at exit doors to the exterior of the building so that maximum travel distance to a call point shall not exceeds 45 meters based on the local and NBC requirements. In the event of fire, the occupant who is rushing through the staircase can operate the manual call point. On operation of the manual call point, the control panel which is located in the centralized location, being monitored round the clock, initiates an alarm through the electronic hooters, while registering the affected zone. 6.4.4 System is compatible for integration with IBMS for monitoring. 6.4.5 Office floors shall be with addressable photoelectric type Smoke detectors and Service areas shall be with Heat detectors. (These smoke and heat detectors having provision to connect the response indicator). Manual pull stations, electronic Hooters & Conduits wiring). 6.4.6 The detectors shall be designed to cover floor plate area of 50 sq.m and each loop shall be associated accessories like fault isolation modules, Control / Monitor modules and Response indicators (the above detectors and devises are provided for only common area s like passenger and service lift lobby s only).
6.5 PUBLIC ADDRESSABLE SYSTEM: Automatic and manual voice evacuation system will be an integral part of life safety system. Automatic voice evacuation alarm tones and messages will be initiated by the Fire alarm system located in FCC. It will be arranged to initiate automatic phased or full evacuation in accordance with the buildings configuration and the requirements of the local fire authorities. The main objective of the EVC System is to convey clear and audible instructions to all the people on all floors / buildings incase of occurrence of fire / other emergency to reach a place of safety in the open, outside the buildings. The sound output should not be so loud that people nearest to the speakers feel uncomfortable, nor so weak that people away cannot listen what is being broadcast. This is achieved by working the system at 60 to 75% power output and distributing speakers uniformly all over floor area. Major Equipments are: The system will comprise of a microphone of suitable technical specification for voice communication, to convert speech into electrical pulses. These pulses will be fed into pre-amplifiers from here, the amplified pulses will be branched off to feed a set of amplifiers, from where the output power is fed to loud - speakers on various floors/buildings obtain the desired objective. The system shall consist of: a. Control consoles b. Amplifiers in Racks c. Speakers d. Fire men telephone jack. e. Connecting cables and Racks for mounting above. The PA console, goose neck mic, PA ON/OFF switch shall be located in Security / BMS room/facility room. Amplifier as required shall be placed in each floor. (As per floor requirement). Proposed design: I. Designed and installed as per Local authority. II. III. IV. P.A. Speakers shall mount on floors near each Staircase, common areas, corridors etc. Announcement shall be done in case of Emergency. Fireman telephone jack/ system. With two ways talk back facility. 6.6 CABLE AND WIRINGS: All wiring for fire detection system shall be stranded plain copper conductor, FRLS (fire resistant Low Smoke)