Presented by SANTANU BHATTACHARYA

ASIA INSTITUTE OF POWER MANAGEMENT

Presented by SANTANU BHATTACHARYA


• Essentially three main constituents are required to start a fire.

• Fuel, Oxygen or air and Heat. • When above three ingredients come together in right

proportion, a fire starts. • It is obvious that Fuel and air will always be there. • Hence, the controllable constituent is heat. • The main thrust in any fire prevention programme will

be to control the heat.

FIRE TRIANGLE

Removal of Heat - Cooling Removal of Oxygen –

Blanketing/Smothering Segregation of Fuel - Starvation


D H

Tank full of Kerosine oil

D = 3 m H = 2 m

Calorific Value of Kerosine + 46.5 MJ/kg

Density of Kerosine = 783 kg/cu.m

Fire Load = (Total Quantity of Combustible x Calorific value) / Area

FIRE LOAD

FIRE LOAD - Measure of the maximum heat that would be released if all the combustibles in a given fire area are burned

Example:

= (3.14xD^2/4 xH) x Density x C.V. / (3.14xD^2/4)

= H x Density x C.V.

= (2 x 783 x 46.5) MJ/sq.m

= 72819 MJ/sq.m


CAUSES OF FIRE

ELECTRICAL 23%

SMOKING 18%

OVERHEATED MATERIAL 8%

HOT SURFACE 7%

BURNER FLAMES 7%

CUTTING & WELDING 4%

MECHANICAL SPARK 2%

STATIC SPARK 1%

SPONTANEOUS IGNITION 4%

FRICTION 10%


INCIDENTS AND CAUSES OF ELECTRICAL FIRE

CASES OF MAJOR ELECTRICAL FIRE IN KOLKATA

• Fire hazard at Nandaram Market – 2008

• Fire hazard at Stephen Court – 2010

• Fire hazard at AMRI Hospital – 2011

• Fire at Food Plaza at Howrah Station – 2012

• Fire hazard at Karnani Estate – 2012

COMMON CAUSES OF ELECTRICAL FIRE

• Causes of Short-Circuit in electrical wiring

• Causes of fire in Fluorescent light

• Causes of fire in Air Conditioner

Showing jumbled up and undressed wiring


MEASURES TO PREVENT SHORT CIRCUIT

• Usage of good quality ISI cables

• Designing of the electrical outlets according to appliance load

• Avoiding joints in wiring

• Renewal of the wiring after ageing

• Proper dressing and clamping of wiring

• Bushing of the dead end of wiring

• Usage of individual socket for each appliance

PERMANENT MEASURES

• Use of MCBs and MCCBs of proper rating

• Implementation of proper earthing system


CLASS OF FIRE

DESCRIPTION EXTINGUISHING MEDIUM

A FIRES INVOLVING ORDINARY COMBUSTIBLE MATERIALS LIKE WOOD, PAPER, TEXTILES ETC. WHERE COOLING EFFECT IS NECESSARY

WATER CO2

B FIRES IN FLAMMABLE LIQUIDS LIKE OILS, SOLVENTS, PETROLEUM PRODUCTS, VARNISHES, PAINTS, ETC. WHERE BLANKETING EFFECT IS ESSENTIAL

FOAM, CO2, DCP, HALON

C FIRES INVOLVING GASEOUS SUBSTANCES UNDER PRESSURE WHERE IT IS NECESSARY TO DILUTE THE BURNING GAS AT A VERY FAST RATE WITH A INERT GAS OR POWDER

C02, DCP, HALON

D FIRES INVOLVING METALS LIKE Mg, Al, Zn, K, ETC. WHERE THE BURNING METAL IS REACTIVE TO WATER

SPECIAL DCP

E FIRES THAT OCCUR DUE TO MALFUNCTIONING OF ELECTRICAL EQUIPMENT

CO2

CLASSES OF FIRE AND SUITABLE FIRE EXTINGUISHER


FIRE EXTINGUISHERS – BASICS / OPERATION PRINCIPLE SL. NO.

TYPE CLASS OF FIRE

USAGE CAPACITY AVAILABLE

EXTINGUISHIN

G EFFECT

METHOD OF OPERATION

IS SPEC. NO.

1 Water CO2 A Fire involving Paper, Wood,

Fabrics and other carbonaceous

materials

9 ltrs 45 ltrs

Striking and cooling

Remove the guard clip and push the

plunger down

940-1987

2 Mechanical Foam

B Fire involving flammable liquids

9lt 45/50 ltrs

Blanketing top surface

Remove the guard clip or safety pin and press plunge down or

open flow control valve or CO2 gas

cartridge

3 Carbon di oxide

BCE Fire involving highly

inflammable, gaseous substance

and electrical equipment

2 to 45 kg Blanketing, cooling, reducing

oxygen percentage in a

localised manner

Remove the safety pin and open the flow control valve

2878-1976

4 Dry Chemical Powder

BC Fire involving highly inflammable liquids and gases

1 to 10, and 25, 50 and

70 kg

Blanketing and chemical reaction

Remove the safety clip and strike the

knob located in the cap

2171-1976


Different stages during progress of fire •Ignitability •Ignition •Growth •Steady Combustion •Decay


• CESC is committed to deliver un interrupted quality power supply to 2.8 Million

consumers of the twin cities of Kolkata & Howrah

• In pursuit to that mission major thrust put in towards up-gradation of equipment and

Modern Fire Detection & Protection arrangement for all important installations

• Replacement of conventional pillar boxes having re-wireable fuse by modified pillar box

with HRC fuse

• Upgrading fire detection and protection system to suit need, embedded with state of

the art technology

• Formulation of procedures to keep response time and acting time within acceptable

limit

• Creating a general awareness among the employees and the public at a large related to

fire safety

• Close liaison with Fire Service Authority to handle emergency fire disaster cases

CESC’s INITIATIVE AGAINST ELECTRICAL FIRE


INITIATIVES OF CESC TO COMBAT FIRE

• Replacement of oil filled HV switchgears by GIS/Vacuum switchboard

• Replacement/installation of Dry type transformer instead of Oil filled transformer at strategic location

• Installation of automatic system for fire control of high risk equipment – High velocity water spray

– Medium expansion foam

– Carbon-di-oxide total flooding

– Dry chemical powder (fixed piping arrangement)

– Nitrogen Drain and Stir (only for Power Transformer)

• Installation of fire/smoke detection and alarm system for offices and vital installations

• Installing fire wall for Power Transformers, Fire Exit/Door in manned premises

• Extensive fire drill for all level employees



FIRE HYDRANT SYSTEM



AUTOMATIC WATER SPRAY SYSTEM FOR FIRE PROTECTION

MEDIUM VELOCITY WATER SPRAY SYSTEM :

FOR CONTROL & COOLING OF FLAMMABLE LIQUID FIRE & NOT FOR QUENCHING

HIGH VELOCITY WATER SPRAY SYSTEM :

FOR FIRE OF FLAMMABLE FLUIDS OF FLASH PT. > 60 degree

APPLICATION : TRANSFORMER / T. G. SET LUB SYSTEM / OTHER OIL FILLED EQUIPMENT

PRINCIPLE : APPLIES WATER IN FORM OF CONICAL SPRAY OF DROPLETS AT HIGH VELOCITY

-- EMULSIFICATION

-- COOLING

-- SMOTHERING

EQUIPMENT : PROJECTORS / DETECTORS / DELUGE VALVE / ALARMS / PUMPS / COMPRESSORS

ADVANTAHES : SPEED ECONOMY FLEXIBILITY RELIABILITY


OPERATION LOGIC

In case of fire, frangible bulb detector provided at the strategic location around the zones shall collapse, thus will allow compressed air to release which in turn shall be sensed by a Pressure Switch for the particular zone and will send an impulse to Control Panel to open the Selector valve after a time lag of 60 sec. to start The fire pump automatically. Main Supply ON/OFF Switch will be used for aborting the automatic actuation incase of spurious alarm or component failure. Manual actuator Switch is also provided in the system. On starting of Fire Pump water at a high pressure will pass through In-line Inductor where the foam compound shall be Inducted by ventury principle of the In-line Inductor and water foam solution shall be expanded and final shall be discharged to the respective zone. Zone No. 5 i.e. Open block area will also operate simultaneously (in case of fire in any zone). Thus the fire will extinguish. The water curtain system consist of piping and Water Curtain Nozzles are also provided at the door opening of the Transformers yard which will also operate incase of fire in any zone to restrict/to stop propogation of fire to inside building

BASIS OF DESIGN

As per standard practice transformers are normally protected by high velocity water spray system which require huge quantity of water to quench transformer fire. Because of the scarcity of water as discussed we have designed the system to protect the Transformer by foam sprinkler system.

29




WATERSPRAY EQUIPMENT

Emulsifire Nozzle

The Emulsifire Nozzle is a high velocity water spray nozzle. It produces a solid cons of coarse water droplets between 1.5 mm and 2.5 mm diameter when used in its normal operating range of 3.5 bar to 5 bar The nozzle has an internal swirl which ensures an even distribution of water within the spray pattern. The swirl has a minimum passage diameter to reduce susceptibility to blockage.

The Emulsifire Nozzle is designed for use in engineered fire protection systems to give exposure protection for capital equipment where a significant throw is required specially where high wind speeds are expected and to control fuel fires involving high viscosity, high flashpoint (above 66 C ) fuels.


MANUAL HIGH VELOCITY WATER SPRAY SYSTEM


MEDIUM EXPANSION FOAM SYSTEM FOAM - Is an aggregate of air filled bubbles formed from aqueous solutions and is lower in density than the lightest flammable liquids.

PRINCIPLE - Forms a coherent floating blanket on flammable and combustible liquids lighter than water. -- extinguishes fire by excluding air -- cooling the fuel -- property to adhere to surface -- provides a degree of exposure -- protection from adjacent fires.

FOAM -- on flammable liquid fire. (USAGE) -- Secure the surface of a flammable liquid which is not burning.

TYPES

FIXED PIPED SEMI FIXED PORTABLE/MOBILE SYSTEMS FOAM MAKER FOAM GENERATOR TRANSPORTED AFTER FIRE -- MONITOR -- FOAM TOWER -- HOSELINES


ADVANTAGES : * Does not break down readily * has the ability to extinguish fire progressively * Flows easily across burning surface to form a tight blanket * Prevents reignition * Heat radiation protection * Insulating characteristics * Cooling effect * reflectivity

EXPANSION - Ratio of final foam vol. to original foam solution volume before adding water/air.

FOAM EXPANSION

LOW UPTO 20

MEDIUM 20 - 200

HIGH 200 - 1000

FOAM SPRINKLER SYSTEM OF DESIGN

Design Standard - NFP, 16 Design discharge Rate - 0.16 OPM/Sq. ft (6.5 LPM/m2 Duration of discharge - 10 minutes at the design rate




FIRE DETECTION & ALARM SYSTEM CLASSIFICATION OF DETECTORS

F I R E SENSE OF VISION SENSE OF SMELL SENSE OF TOUCH

PHOTOELECTRIC SMOKE DETECTOR

LIGHT SCATTERING

LIGHT OBSCURATION

FLAME DETECTOR

FLAME FLICKER

INFRARED

ULTRAVIOLET

IONISATION SMOKE DETECTOR

GAS SENSING DETECTOR

SEMICONDUCTOR TYPE

CATALYTIC TYPE

FIXED TEMPERATURE HEAT DETECTOR

RATE OF RISE HEAT DETECTOR

PNEUMATIC TUBING

PNEUMATIC DETECTOR

QUARTZOID BULB

BIMET ALLIC

LINEAR HEAT SENSING CABLE

FUSIRLE ALLOY

THERMOEL ECTRIC

ELECTRICAL CONDUCTIVITY RATE OF CHANGE


FIRE/SMOKE DETECTION AND ALARM SYSTEM

Main controlling unit

Receives the signals from the smoke/heat detectors from a particular zone

Actuates hooters and the Mimic Panels

Consists of :

Zone Cards for each zone with LED displays indicating FIRE, ISOLATION OPEN, TEST

System Card with LED displays indicating whether AC supply has failed or not, low battery voltage, battery charger on etc.

Piezoelectric Sounder giving audio signal during fire condition, ‘AC supply fail’ condition, etc.


Each detector has an inbuilt LED which glows whenever the detector senses fire

RESPONSE INDICATOR

Installed wherever the detector is installed inside a closed room/cabin or above the false ceiling When the detector senses fire, the LED in the RI also glows

DETECTORS

Smoke/heat detectors installed at strategic positions.

Senses smoke/heat caused by fire and sends signal to the main control panel

MIMIC PANEL

Installed outside main entrance in each floor containing a diagram of the floor with positions of the installed detectors in each zone Has LED displays of each zone in that floor

HOOTER

Heavy duty electronics hooters in each floor which give audible signal in case of fire


MANUAL PILL BOXES

Contains a switch which may be operated by breaking the glass cover guarding it with a hammer attached to the equipment by a chain

Once somebody observers fire at some location which has not yet activated the nearest detector, he can break the glass and raise the alarm throughout the building


AUTOMATIC CO2 FIRE EXTINGUISHING SYSTEM

CARBON –DI-OXIDE AS AN EXTINGUISHING MEDIUM Carbon Dioxide is a dry, inert, non-corrosive and electrically non-conducting gas which extinguishes fire by diluting the atmosphere to a point where the oxygen content is no longer sufficient to support combustion. Its most valuable property is its high expansion ratio. CO2 is stored in cylinders in humid from under pressure and when released discharges from the cylinder by force of its own expansion.

HOW A CO2 EXTINGUISHING SYSTEM WORKS

An installation consists of a battery of one more CO2 cylinders with a common manifold, connected to a system of distribution pipes terminating in special discharge nozzles. In case of fire, signal from the fire detectors located in the hazard area releases the CO2 automatically via the Control Panel. Automatic systems are electrically operated. But all systems can also be actuated manually. CO2 is discharged at a very low temperature. It, therefore, extinguishes fire both by reducing the content of O2 from its normal value of 21% in air to 11% in the hazard area and also to a certain extent by its cooling effect.

ADVANTAGES

High expansion ratio. This ensures sufficient proportion for discharging from cylinders by force of its own expansion.


Being heavier than air it penetrates every crack and crevice to extinguish fire.

APPLICATION

Battery Room

Control Room

Cable Basement

Switch Floor

DIFFERENT TYPES OF CO2 AUTOMATIC EXTINGUISHING SYSTEMS PRESENT IN CASE’s NETWORK

1) Pneumatic Arrangement

2) Pull Chord Arrangement

3) Weight Rod Arrangement






NITROGEN INJECTION DRAIN & STIR SYSTEM



TRIP LOGIC DIAGRAM FOR FIRE PROTECTION

FIRE DETECTION

PRV TRIP OR

BUCH. TRIP

HV REF

OR

LV REF

DIFF. TRIP

A N D

33KV CB OFF

132KV CB OFF

SOLINOID COIL (AT FIRE PNL.)


N2

B – Prevention Mode

System Design

1/ Pressure increases

2/ The PRV opens

4/ Nitrogen injection starts

3/ The fast oil drain starts

5/ Explosive gas generation Stops


Working Principle :

• A glass bulb detector (designed temperature -79 deg C) is provided at the bottom of the container which senses the heat of fire and subsequently bursts thus allowing the DCP provided in the container to discharge on the fire risk below in the form of a 90 deg. cone which puts the fire out.

DCP

Container

with glass

bulb detector

Modular Dry Chemical Powder ( DCP) type automatic Fire Extinguisher


TRANSFORMER

MODULAR

DCP

TRANSFORMER

PLINTH


PRINCIPLE OF EVACUATION TECHNIQUE ADOPTED IN CESC

Time Needed to Escape (TNE) ≤ Time Available for Escape (TAE)

Depends on No. of occupants Familiarity of room Size & shape of building and floor layout Obstacles en route

Duration between starting of the fire till the time when the room become unsafe

One must escape to a safe place. Safe place means open and level ground with sky above.


EVACUATION PSYCHOLOGY & ROLE OF OCCUPIERS

• Essential to remain calm and evacuate in an orderly manner avoiding panic

• Evacuation shall be guided by one trained and authorised incident leader

• Exit by stair only – elevator not to be used

• On detecting fire do not open windows and doors as increased ventilation may enhance fire

• Walking on knees with wet towel on the face is the best way to move out of the room with smoke

• After evacuation head count is essential

All these can be achieved by proper training and fire drill


Date post:	16-Jan-2022
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Presented by SANTANU BHATTACHARYA

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