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Fire Protection, Fire Detection

and

Fire Extinguishing

Mohd. Hanif Dewan, Senior Engg. Lecturer,

International Maritime Academy, Bangladesh

FIRE

WHAT IS FIRE? Fire is a chemical process, which involves burning of any substance (combustion). The combustible material that burns with the help of oxygen result in the production of heat & light, is called FIRE

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Fire is not always harmful but only when it goes out of control.

Mohd. Hanif Dewan, Senior Engg. Lecturer, International Maritime Academy, Bangladesh

FIRE HAZARDS / SOURCES

Short Circuits (faulty electrical wires and switchboards) Naked Lights Explosive and fire works Unmindful Smoking Radiation Mechanical heat & spark Spontaneous combustion

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Mechanical sparks from grinding, chipping or welding friction or funnel sparks are low- energy sparks which may start a smoldering fire Electric sparks, sparks from electrostatic discharge and high energy mechanical sparks may ignite flammable vapors Electric arc welding

Sparks

Hotplates Heating pipes Exhaust manifolds Faulty machinery Electric light bulbs

Hot surfaces

Smoking materials Oil-fired boilers Incinerators Hot work such as flame cutting and gas welding.

Flames or smoldering sources

Examples Type of Sources


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Substances liable to self-heat (usually due to oxidation) Fibrous material soaked in organic oils such as vegetable oils, the oils used in paints or hydraulic oils. Rotting vegetable matter Chemicals or organic materials contaminated with an oxidizing agent such as sewage treatment tablets Mineral oils and carbonaceous materials are liable to self heating if external heating is applied first Metal dwarf especially if contaminated with oil and rags

Spontaneous combustion

Overloaded wiring or equipment with a short circuit or a short to earth Electrical overheating


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TYPES OF FIRES

As of new definitions of IMO, May 2007, there are 6 types of fire onboard ships: Class A: Fires that involve flammable solids such as wood, cloth,paper and some plastics. Class B: Fires that involve flammable liquids or liquifiable solids such as petrol, oil, paint and some waxes and plastics (BUT NOT cooking fats or oils). Class C: Fires that involve flammable gases such as methane propane hydrogen


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Class D: Fires that involve combustible metals such as sodium, magnesium, and potassium. Class E: Fires that involve any of the materials found in Class A and B fires: BUT ALSO with the introduction of an electrical appliances, wiring, or other electrically energized objects in the vicinity of the fire, with a resultant electrical shock risk if a conductivity agent is used to control the fire. Class F: Fires involving cooking fats and oils.

The high temperature of the oils when on fire far exceeds that of other flammable liquids making normal extinguishing agents ineffective


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FIRE TRIANGLE

To understand how fire extinguishers work, you need to understand a little about fire.

Fire is a very rapid chemical reaction between oxygen and a combustible material, which results in the release of heat, light, flames, and smoke.

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HEAT/ENERGY Mohd. Hanif Dewan, Senior Engg. Lecturer, International Maritime Academy, Bangladesh

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FIRE TRIANGLE

For fire to exist, the following four elements must be present at the same time: Enough oxygen to sustain combustion, Enough heat to raise the material to its ignition temperature, Some sort of fuel or combustible material, and The chemical reaction (FIRE)

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The components of the fire tetrahedron: fuel, heat, oxygen and chemical chain reaction


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Dont Make a Fire Triangle!

Understanding the three sides of the fire triangle, and being able to recognize them in everyday situation is the key to fire prevention.

FUEL FUEL

Remember: Where there is fuel and air keep heat away Where there is air and heat keep fuel away Where there is heat and fuel keep air away NEVER COMPLETE THE FIRE TRIANGLE !

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FIRE SPREAD

Fire spreads by CONDUCTION: transfer of heat through solid

body. CONVECTION: through the motion of heated

matter, i.e. through the motion of smoke, air, gases etc. produced by fire.

RADIATION: heat radiation is the transfer of heat from a source without a material substance being involved.

12 Mohd. Hanif Dewan, Senior Engg. Lecturer, International Maritime Academy, Bangladesh

Conduction

Transfer of heat through a solid body such as metals as a very good conductor of heat. Since most ships are constructed by metal, heat transfer by conduction is a potential hazard. Fire can easily move from one compartment to another, one deck to another, and one compartment to another because of heat conduction. Heat is being conducted to the adjoining spaces by the metal deck and bulkhead, then the bulkhead paint is blistering (extremely hot) because vapourization has already begun. 4/7/2014 13


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CONDUCTION

An example of conduction: The temperature along the rod rises because of the increased movement of molecules from the heat of the flame.


Radiation

Heat radiation is the transfer of heat from a source across the space or travels outward from the fire in the same manner as light in straight lines to produce vapour and then igniting the vspour. When contacts a body, it is absorbed, reflected or transmitted. Absorbed heat increases the temperature of the absorbing body. Heat radiates in all directions unless it is obstructed


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Radiation: The transmission of energy as an electromagnetic wave without an intervening medium.

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Convection

The transfer or carries of heat through a liquid or gaseous body such as movement of smoke, hot air and heated gases produced by fire. The replacement of hot and cool air to that particular point resulting in reheated and raised the temperature thus create a fire


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CONVECTION

Convection: The transfer of the heat energy by the movement of heated liquids or gases.


Fire hazards in engine room Combustible liquids FO, DO, LO Oil leaks & oil soaked insulation Hot surfaces exhaust pipes, engine parts

overheating Defects in lagging Hot work welding, cutting, oxy acetylene Auto ignition oil dripping on hot surface auto-ignition, e.g. oil dripping on hot surface

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Fire hazards in galley Combustible liquids cooking oil, hot fat Hot surfaces - ovens, frying pans, flues Defective electrical connections


Fire hazards in accommodation Combustible materials - furnishing, personal effects Matches and cigarette smoking Defective or overloaded electrical systems


Fire hazards from cargoes

Self-heating cargo & spontaneous combustion Oxidizing cargoes and organic peroxides Compressed flammable gas Pyrophoric cargoes flammable liquids and solids substances liable to react with Themselves Water Other cargoes Materials of the ship Explosives


Four phases of fire development

Ignition (incipient) Developing (surfaces fire) Absolute fire (fire in depth in solids) Burning out To consider; Temperature of normal fire such as coal, wood or

hydrocarbon fires, and the temperature in burning metals Effect of temperature rise on the rate of the chain reaction - fire intensity


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FIRE DETECTION Fire detection systems are compulsory in ships which have periodically unattended machinery spaces. A fire detection system consists of the following elements: Human observation Manual fire alarms Automatic Fire detectors-smoke, flame,heat (gas, H2S) Combinations of the above Fire detection system requirements are detailed in SOLAS CHAPTER II-2 Human observation relies on the human senses: Sight Sound Smell Taste Touch Mohd. Hanif Dewan, Senior Engg. Lecturer,


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METHOD OF FIRE DETECTION: Sight- Infra red flame detectors, sensing flicker patterns, smoke detectors using light sources in go or no go light transmission and reception. Sound-not really yet! Smell and Taste- combustion products entering an ionized chamber. Touch- Heat detectors, including absolute temperature and rate of rise temperatures.


AUTOMATIC FIRE DETECTION SYSTEMS

Automatic fire detection systems, when combined with other elements of an emergency response and evacuation plan, can significantly reduce property damage, personal injuries, and loss of life from fire in the workplace. Their main function is to quickly identify a developing fire and alert building/Office occupants and emergency response personnel before extensive damage occurs. Automatic fire detection systems do this by using electronic sensors to detect the smoke, heat, or flames from a fire and providing an early warning.


Manual Fire Detection - Pull Stations

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Manual fire detection is the oldest method of detection. In the simplest form, a person yelling can provide fire warning. Onboard a ship, however, a person's voice may not always transmit throughout the structure and machinery sound. For this reason, manual alarm stations are installed. The general design philosophy is to place stations within reach along paths of escape. It is for this reason that they can usually be found near exit doors in corridors and large rooms.

The advantage of manual alarm stations is that, upon discovering the fire, they provide occupants with a readily identifiable means to activate the building fire alarm system. The alarm system can then serve in lieu of the shouting person's voice. They are simple devices, and can be highly reliable when the building is occupied. The key disadvantage of manual stations is that they will not work when the building is unoccupied. They may also be used for malicious alarm activations. Nonetheless, they are an important component in any fire alarm system. A manually operated device used to initiate an alarm signal.


Automatic Detectors Spot type

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Spot Type Detector. A device in which the detecting Element is concentrated at a particular location. Typical examples are Bimetallic detectors, fusible alloy detectors, certain pneumatic rate-of-rise Detectors, certain smoke detectors, and thermoelectric detectors.


Automatic Detectors Photoelectric

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Light Scattering Smoke Detection. The principle of using a light source and a photosensitive sensor arranged so that the rays from the light source do not normally fall onto the photosensitive sensor. When smoke particles enter the light path, some of the light is scattered by reflection and refraction onto the sensor. The light signal is processed and used to convey an alarm condition when it meets preset criteria.

Hochiki SLR-24V detector


Automatic Detectors Ionization

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Ionization smoke detectors use an ionization chamber and a source of ionizing radiation to detect smoke. This type of smoke detector is more common because it is inexpensive and better at detecting the smaller amounts of smoke produced by flaming fires.

Inside the ionization detector is a small amount (perhaps 1/5000th of a gram) of Americium-241. The radioactive element americium has a half-life of 432 years, and is a good source of alpha particles.

An ionization chamber is very simple. It consists of two plates with a voltage across them, along with a radioactive source of ionizing radiation.


Ionization Smoke detector

Ionization Smoke Detection. The principle of using a small amount of radioactive material to ionize the air between two differentially charged electrodes to sense the presence of smoke particles. Smoke Particles entering the ionization volume decrease the conductance of the air by reducing ion mobility. The reduced conductance signal is processed and used to convey an alarm condition when it meets preset criteria.


Automatic Detectors Ionization

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Ionization Smoke detectors The alpha particles generated by the americium have the following property: They ionize the oxygen and nitrogen atoms of the air in the chamber. To "ionize" means to "knock an electron off of." When you knock an electron off of an atom, you end up with a free electron (with a negative charge) and an atom missing one electron (with a positive charge). The negative electron is attracted to the plate with a positive voltage, and the positive atom is attracted to the plate with a negative voltage (opposites attract, just like with magnets). The electronics in the smoke detector sense the small amount of electrical current that these electrons and ions moving toward the plates represent.


Ionization Smoke detectors When smoke enters the ionization chamber, it disrupts this current -- the smoke particles attach to the ions and neutralize them. The smoke detector senses the drop in current between the plates and sets off the horn.


Smoke Detectors Ionization Detectors The ionization detector contains a small radioactive source that is used to charge the air inside a small chamber. The charged air allows a small current to cross through the chamber and complete an electrical circuit. When smoke enters the chamber, it shields the radiation, which stops the current and triggers an alarm. These detectors respond quickly to very small smoke particles (even those invisible to the naked eye) from flaming or very hot fires, but may respond very slowly to the dense smoke associated with smoldering or low-temperature fires.

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Smoke Detectors Photoelectric Detectors

In a photoelectric smoke detector, a light source and light sensor are arranged so that the rays from the light source do not hit the light sensor. When smoke particles enter the light path, some of the light is scattered and redirected onto the sensor, causing the detector to activate an alarm. These detectors react quickly to visible smoke particles from smoldering fires, but are less sensitive to the smaller particles associated with flaming or very hot fires.

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Smoke detectors must not operate below 2% obscuration per metre, but must activate before 12.5% obscuration. Heat detectors must not operate below 540C but must operate before 780C. However, in certain cases the heat detector limits may be increased by 300C

Type AREA ( MAX) DISTANCE

APART

Distance

From

Bulkhead

HEAT 37m2 9m 4.5m

SMOKE 74m2 11m 5.5m


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Smoke and heat detectors must also be sited to avoid stratification: that is the detector must not be blanketed by layers of hot air.


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In this case, the increasing convection air currents have created a flow of combustion products across the detectors.


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As shown, detector heads must be positioned to allow easy passage of combustion products in all fire scenarios


Automatic Detectors Heat/Thermal

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Heat Detector. A fire detector that detects either abnormally high temperature, or rate of temperature rise, or both.

Heat detectors are the oldest type of automatic fire detection device. They began development of automatic sprinklers in the 1860s and have continued to the present with proliferation of various types of devices. Heat detectors that only initiate an alarm and have no extinguishing function are still in use. Although they have the lowest false alarm rate of all automatic fire detector devices, they also are the slowest in fire detecting. A heat detector is best situated for fire detection in a small confined space where rapidly building high-output fires are expected, in areas where ambient conditions would not allow the use of other fire detection devices, or when speed of detection is not a prime consideration. Heat detectors are generally located on or near the ceiling and respond to the convected thermal energy of a fire. They respond either when the detecting element reaches a predetermined fixed temperature or to a specified rate of temperature change. In general, heat detectors are designed to operate when heat causes a prescribed change in a physical or electrical property of a material or gas.

Heat detectors can be sub-divided by their operating principles: Mohd. Hanif Dewan, Senior Engg. Lecturer, International Maritime Academy, Bangladesh

Automatic Detectors Fixed Temp.

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Fixed-Temperature Detector. A device that responds when its operating element becomes heated to a predetermined level.

Fixed-temperature heat detectors are designed to alarm when the temperature of the operating elements reaches a specific point. The air temperature at the time of alarm is usually considerably higher than the rated temperature because it takes time for the air to raise the temperature of the operating element to its set point. This condition is called thermal lag. Fixed-temperature heat detectors are available to cover a wide range of operating temperatures - from about 135'F (57'C) and higher. Higher temperatures detectors are also necessary so that detection can be provided in areas normally subject to high ambient temperatures, or in areas zoned so that only detectors in the immediate fire area operate.

Heat Detector


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HEAT DETECTION

BI METALLIC STRIP


Heat Detectors

Heat detectors are normally used in dirty environments or where dense smoke is produced. Heat detectors may be less sensitive, but are more appropriate than a smoke detector in these environments. The most common heat detectors either react to a broad temperature change or a predetermined fixed temperature.

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Heat Detectors

Heat detectors use a set of temperature-sensitive resistors called thermistors that decrease in resistance as the temperature rises. One thermistor is sealed and protected from the surrounding temperature while the other is exposed. A sharp increase in temperature reduces the resistance in the exposed thermistor, which allows a large current to activate the detector's alarm.

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Automatic Detectors Rate-of-Rise

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Rate-of-Rise Detector. A device that responds when the temperature rises at a rate exceeding a predetermined value

One effect that flaming fire has on the surrounding area is to rapidly increase air temperature in the space above the fire. Fixed-temperature heat detectors will not initiate an alarm until the air temperature near the ceiling exceeds the design operating point. The rate-of-rise detector, however, will function when the rate of temperature increase exceeds a predetermined value, typically around 12 to 15'F (7 to 8'C) per minute. Rate-of-rise detectors are designed to compensate for the normal changes in ambient temperature that are expected under non-fire conditions.

Hochiki DSC-EA Heat Detector


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HEAT DETECTION

RATE OF RISE: TWO BI METALLIC STRIPS


Automatic Detectors Combination

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Combination Detector. A device that either responds to more than one of the fire phenomena or employs more than one operating principle to sense one of these phenomena. Typical examples are a combination of a heat detector with a smoke detector or a combination of rate-of-rise and fixed temperature heat detector. This device has listings for each sensing method employed.

Combination detectors contain more than one element which responds to fire. These detectors may be designed to respond from either element, or from the combined partial or complete response of both elements. An example of the former is a heat detector that operates on both the rate-of-raise and fixed-temperature principles. Its advantage is that the rate-of-rise element will respond quickly to rapidly developing fire, while the fixed-temperature element will respond to a slowly developing fire when the detecting element reaches its set point temperature. The most common combination detector uses a vented air chamber and a flexible diaphragm for the rate-of-rise function, while the fixed-temperature element is usually leaf-spring restrained by a eutectic metal. When the fixed-temperature element reaches its designated operating temperature, the eutectic metal fuses and releases the spring, which closes the contact.

Hochiki DCD Series Fixed Temp/Rate of Rise Heat Detector

Hochiki Photoelectric/Heat Smoke Detector


Automatic Detectors Flame

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Flame Detector. A radiant energy-sensing detector that detects the radiant energy emitted by a flame. Radiant Energy-Sensing Fire Detector. A device that detects radiant energy, such as ultraviolet, visible, or infrared, that is emitted as a product of combustion reaction and obeys the laws of optics.

A flame detector responds either to radiant energy visible to the human eye (approx. 4000 to 7700 A) or outside the range of human vision. Similar to the human eye, flame detectors have a 'cone of vision', or viewing angle, that defines the effective detection capability of the detector.

With this constraint, the sensitivity increases as the angle of incidence decreases. Such a detector is sensitive to glowing embers, coals, or flames which radiate energy of sufficient intensity and spectral quality to actuate the alarm. Each type of fuel, when burning, produces a flame with specific radiation characteristics. A flame detection system must be chosen for the type of fire that is probable. For example an ultraviolet (UV) detector will respond to a hydrogen fire, but an infrared (IR) detector operating in the 4.4 micron sensitivity range will not. It is imperative therefore; that a qualified fire protection engineer is involved in the design of these systems, along with assistance from the manufacturer's design staff.


Automatic Detectors Flame

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Due to their fast detection capabilities, flame detectors are generally used only in high-hazard areas, such as fuel-loading platforms, industrial process areas, hyperbaric chambers, high-ceiling areas, and atmospheres in which explosions or very rapid fires may occur. Because flame detectors must be able to 'see' the fire, they must not be blocked by objects placed in front of them. The infrared-type detector, however, has some capability for detecting radiation reflected from walls.

Hochiki HF-24 Flame Detector


Flame Detectors

Flame detectors are line-of-sight devices that look for specific types of light (infrared, visible, ultraviolet) emitted by flames during combustion. When the detector recognizes this light from a fire, it sends a signal to activate an alarm.

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INFRA RED DETECTOR Detects radiation in a particular narrow band flame flicker Can be confused by flickering lights, hence built in time delay.


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This detector senses the ultra violet spectrum of a flame and is less sensitive to false alarms.


Automatic Detectors Linear Type

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Line-Type Detector. A device in which detection is continuous along a path. Typical examples are rate-of-rise pneumatic tubing detectors, projected beam smoke detectors, and heat sensitive cable.

Projected Beam-Type Detector. A type of photoelectric light obscuration smoke detector wherein the beam spans the protected area. Photoelectric Light Obscuration Detection. The principle of using a light source and a photosensitive sensor onto which the principal portion of the source emission is focused. When smoke particles enter the light path, some of the light is scattered and some of the light is absorbed, thereby reducing the light reaching the receiving sensor. The light reduction signal is processed and used to convey an alarm condition when it meets preset criteria.


Automatic Detectors Air Sampling

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Air Sampling-Type Detector. A detector that consists of a piping or tubing distribution network that runs from the detector to the area(s) to be protected. An aspiration fan in the detector draws air form the protected area back to the detector through air sampling ports, piping, or tubing. At the detector, the air is analyzed for fire products.


Installation For fire detection devices to give a prompt warning

of a fire, they must be appropriate for the location you want to protect . Detector selection Fire detectors should be selected based on the burning characteristics of the materials present and the nature of location they will be used to protect.


Detector selection 1

Smoke detectors

Ionization or photoelectric smoke detectors are designed to identify a fire during its smoldering or early flame stages and will meet the needs of most areas containing primarily wood, paper, fabric, and plastic materials. During combustion, these materials produce a mixture of smoke types with detectable levels of both large and small smoke particles. Smoke detectors are suitable for: Indoor areas with low ceilings such as offices, closets, and restrooms. Areas that are relatively clean with minimal amounts of dust and dirt. Areas that contain solid fuels like wood, paper, fabric, and plastic materials. 4/7/2014 59


Detector selection 2

Heat detectors

Heat detectors are ideal for areas where flammable gasses and liquids are handled or any area where a fire will quickly cause a large change in the surrounding temperature. Heat detectors are also suitable for: Dirty, dusty or smoky environments. Indoor areas without winds or drafts that can prevent heat from reaching the detector. Manufacturing areas where large quantities of vapors, gases, or fumes may be present. Areas where particles of combustion are normally present, such as in kitchens, furnace rooms, utility rooms, and garages or where ovens, burners or vehicle exhaust gases are present.


Detector selection 3 Flame detectors

Flame detectors are best for protecting: Areas with high ceilings and open-spaces, such as

warehouses and auditoriums. Outdoor or semi-enclosed areas, where winds or draughts can prevent smoke from reaching a heat or smoke detector. Areas where rapidly developing flaming fires can occur, such as petrochemical production, fuel storage areas, paint shops, and solvent areas. Environments that are unsuitable for other types of detectors.


General guidelines for placing fire

detectors Put at least one detector in each room, storage area, and hallway. You may need more than one detector per room for those that exceed the manufacturer's spacing requirements. For example, if your detector is rated for 30 feet, install detectors so they are evenly spaced with no more then 30 feet between detectors. Place the detector as close to the center of the ceiling as possible when only one detector is required in a room or space. Put at least one detector in each closet, elevator and other enclosed spaces. Place a detector at the top of each flight of stairs.


Placing Fire Detectors Place the detectors in the

path of the air flow toward the return air duct when air supply or return ducts are present in a room or space. Place all smoke detectors at least three feet from ceiling fans.

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Maintenance and testing

Over time, dust, dirt, and other foreign material can build up inside a detectors sensing elements, resulting in reduced sensitivity, which can limit the amount of warning time given during a fire. Dirty or dusty detectors can also result in unwanted alarms that can desensitize occupants to the alarm system or produce more serious behavior (such as disconnecting the system altogether). To avoid malfunctions and unwanted alarms and to make sure your fire detection system will perform as expected in the event of a fire, you are required to: Operate and maintain your system in a working condition, making sure it is always turned on, except during repairs or maintenance.


Maintenance and testing Test and adjust fire detectors and fire detection systems often to ensure that they operate correctly and maintain reliability. Detectors found to be unreliable and/or with reduced sensitivity must be replaced or cleaned and recalibrated. Have a qualified person service, maintain and test all fire detection systems, including cleaning and necessary sensitivity adjustments. Have fire detectors cleaned on a regular basis as necessary to assure their proper operation.


Maintenance and testing

All fire detection equipment must be returned to normal operation as soon as possible after being tested, used, or accidentally activated.

`Note: You are also required to have spare detection devices and components readily available in the workplace or from a local supplier to ensure prompt restoration of the system.


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TESTING A SMOKE DETECTOR


Notification/ Alarming Appliances

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Notification/ Alarming Appliance. A fire alarm system component such as a bell, horn, speaker, light or text display that provides audible, tactile, or visible outputs, or any combination thereof.

Audible Alarming Appliance. A notification appliance that alerts by the sense of hearing.

Visible Alarming Appliance. A notification appliance that alerts by the sense of sight.


Fire Alarm Circuit Classes

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Class. Initiating device circuits, notification appliance circuits, and signaling line circuits shall be permitted to be designated as either Class A or Class B, depending on their performance during nonsimultaneous single circuit fault conditions as specified by the following: (1) Initiating device circuits and signaling line circuits that transmit an alarm or supervisory signal, or notification appliance circuits that allow all connected devices to operate during a single open or a nonsimultaneous single ground fault on any circuit conductor, shall be designated as Class A.

(2) Initiating device circuits and signaling line circuits that do not transmit an alarm or supervisory signal, or notification appliance circuits that do not allow all connected devices to operate beyond the location of a single open on any circuit conductor, shall be designated as Class B.

An open or ground fault condition shall result in the annunciation of a trouble signal at the protected premise within 200 seconds as required in 4.4.7


Class B Initiating Device Circuit

4.7K EOLR

4.7K EOLR

Class B Notification Appliance Circuit

Class B Circuits

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End of line supervision resistors are required to supervise the integrity of the loop. Mohd. Hanif Dewan, Senior Engg. Lecturer,


Single open circuit condition causes a trouble on the panel and renders all devices beyond the fault inoperative.

Class B Initiating Device Circuit

4.7K EOLR

4.7K EOLR

Class B Notification Appliance Circuit

Class B Circuits


Class A Initiating Device Circuit

Class A Notification Appliance Circuit

Class A Circuits

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End of line supervision resistors are not necessary as the loop returns to the panel and is driven from both ends. Mohd. Hanif Dewan, Senior Engg. Lecturer, International Maritime Academy, Bangladesh

Class A Initiating Device Circuit

Class A Notification Appliance Circuit

Class A Circuits

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Single open circuit condition causes a trouble on the panel. All devices on the loop remain operative.


Analog Addressable Sensor - An initiating device that transmits a signal indicating varying dAddressable Device - A fire alarm system component with discreet identification that can have its status individually identified or that is used to individually control other functions. egrees of condition as contrasted with a conventional or addressable initiating device, which can only indicate an off/on condition. Signaling Line Circuit (SLC) - A circuit or path between any combination of circuit interfaces, control units, or transmitters over which multiple system input signals or out put signals or both are carried. SLC Interface - A system component that connects a signaling line circuit to any combination of initiating devices, initiating device circuits, notification appliances, notification appliance circuits, system control outputs and other signaling line circuits.

Protocol - A language for communicating between control panels and their proprietary devices.

Additional Fire Alarm Terminology


Conventional control panels range in size from 1 zone to over 100 zones.

Zones typically consist of some or all of the initiating devices in an area or floor of a building.

Some control panels zone capacity is expandable while others are not, limiting its usefulness if a facility adds additional buildings or rooms.

Comparing System Types To better understand todays newer technology, a firm understanding of the types of systems available is necessary. The three most popular types of systems installed today are:

Conventional Addressable Analog Addressable

Conventional Systems



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Zone 1

4.7K EOLR

Zone 2 FIRE FIRE

SILENT KNIGHT

FIRE FIRE

SILENT KNIGHT

FIRE FIRE

SILENT KNIGHT

FIRE FIRE

SILENT KNIGHT

FIRE FIRE

SILENT KNIGHT

FACP

NAC 1

Multiple devices are combined into a single zone. Zones can contain 30 or more devices.

4.7K EOLR



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Care must be taken when laying out zones to comply with code requirements.

Zone 1

4.7K EOLR

Zone 2 FIRE FIRE

SILENT KNIGHT

NAC 1

4.7K EOLR



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Wiring must be installed in a supervised manner either Class A, or Class B with an EOLR.

Zone #1

4.7K EOLR

4.7K EOLR

Zone #2

NAC #1



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Alarm conditions are annunciated by zone only. Inspection is required to determine the device.

Zone #1

4.7K EOLR

4.7K EOLR

Zone #2

NAC #1

FIRE!



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Trouble conditions are annunciated by zone only. Inspection is required to determine the cause.

4.7K

EOLR

Zone #1

4.7K EOLR

4.7K EOLR

Zone #2

NAC #1


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A simplified view of the layout of a fire detection system, featuring normal/emergency power supply, UPS,Loop,Zone Indicators, Alarms, Test switch and Fire Zones.


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CABLE LAYOUT LOOP and LINE monitoring

LOOP MONITORING The continuity of the cable is checked by both circuits a-d and b-c. In the event of either cable failing due to damage the an alarm sounds.


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CABLE LAYOUT

LOOP MONITORING Failure modes-damage causes open or short circuit on cables. Short circuit, no discrimination between faults and FIRE activation. Open circuit, fault alarm on one wire


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CABLE LAYOUT

LOOP MONITORING In each case faults must be examined immediately Whilst the fault condition exists subsequent fire detection is inhibited Easier for accurate fault detection, discriminates between fault and fire but more expensive.


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Line monitoring: Damage to loop Short circuit shuts down the system and gives Fire alarm. Open circuit raises fault indication Less reliable, harder to pinpoint faults but cheaper.


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FIRE EXTINGUISHING METHODS

Method of Extinguishing Fire:

Starvation: Removing or Limiting fuel Smothering: Removing or Limiting Oxygen (Air) Cooling: Limiting or Decreasing Heat/Temperature Inhibition: Stopping/Breaking chemical reaction which is building up heat and rise in temperature (Exothermic Reaction)


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Fire Extinguishing Agents

COOLING: WATER SMOTHERING: FOAM, CARBON DIOXIDE, SAND, FIRE BLANKET

FLAME INHIBATORS: DRY CHEMICAL POWDER (MONO-AMMONIUM PHOSPHATE), HALON


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FIRE FIGHTING SYSTEMS

All fire fighting systems are used to either: Remove Heat

Remove Oxygen Remove fuel or

CHAINBREAK-stop the chemical reaction


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FIRE FIGHTING SYSTEMS Water acts by:- Removing heat as it turns to steam. Blanketing (excluding oxygen) when it turns to steam. Water can only be used safely on fires of class A and C and to boundary cool to stop the spread of fire. Water is electrically conductive therefore cannot be used on class E fires.

The use of water on board ship may be limited by stability criteria (free surface effect).


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FIRE MAIN A sea water supply system to fire hydrants is fitted to every ship. Several pumps in the engine room will be arranged to supply the system, their number and capacity being dictated by legislation (MCA for UK registered vessels as well as LLOYDS RULES) An emergency fire pump will also be located remote from the machinery space and with independent means of power. A system of hydrant outlets, each with an isolating valve, located around the ship, and hoses with appropriate snap-in connectors are strategically located together with nozzles.


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FIRE MAIN (Contd) These nozzles are usually of the jet/spray type providing either type of discharge as required. All the working areas of the ship are thus covered, and a constant supply of seawater can be brought to bear at any point to fight a fire. While sea water is best used as a cooling agent in fighting Class A fires it is possible, if all else fails, to use it to fight Class B fires. The jet/spray nozzle would be adjusted to provide a fine water spray which could be played over the fire to cool it without spreading. An international shore connection is always carried on board ship. This is a standard size flange which is fitted with a coupling suitable for the ship's hoses.


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FIREMAIN LAYOUT


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INTERNATIONAL SHORE

CONNECTION


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INTERNATIONAL SHORE

CONNECTION


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The fire main has a number of dedicated fire pumps: - Main fire pumps, located in the main machinery spaces. - Emergency fire pumps remotely located and independently powered. - In addition, isolation valves are fitted so that the main fire pumps and emergency fire pumps can independently pressurise the fire main. - Further isolation valves so that the accommodation and main deck can be pressurised independently.


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Certain areas, such as the paint locker are protected by manually operated spray systems, supplied by the Fire main.

Tankers on specific operations, which may involve high sulphur fuel, can be equipped with water drencher systems to cover the accommodation and protect it from hydrocarbon gas or H2S releases Other specalised vessels provide manual water curtains at lifeboat embarkation points.


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Automatic FRESH water spray The automatic spray or sprinkler system provides a network of

sprinkler heads throughout the protected spaces. This system may

be used in accommodation areas, and in machinery spaces with

certain variations in the equipment used and the method of

operation.

The accommodation areas are fitted with sprinkler heads which

both detect and extinguish fires. Sprinkler head is closed by a

quartzoid bulb which contains a liquid that expands considerably

on heating.

When excessively heated the liquid expands, shatters the bulb and

water will issue from the sprinkler head. A deflector plate on the

sprinkler head causes the water to spray out over a large area.


Automatic Fire Sprinklers Fire sprinklers are most effective during the fire's

initial flame growth stage. A properly selected sprinkler will detect the fire's heat, initiate alarm and begin suppression within moments after flames appear. In most instances sprinklers will control fire advancement within a few minutes of their activation. This will in turn result in significantly less damage than otherwise would happen without sprinklers.


Automatic Fire Sprinklers Sprinkler systems offer several benefits to building

owners, operators, and occupants. These benefits include: Immediate identification and control of a developing fire. Immediate alert. Reduced heat and smoke damage. Enhanced life safety. Design flexibility. Enhanced Security.


Automatic Fire Sprinklers For most fires, water represents the ideal extinguishing agent. Fire sprinklers utilize water by direct application onto flames and heat. This action cools the combustion process and prevents ignition of adjacent combustibles. Sprinkler systems are essentially a series of water pipes which are supplied by a reliable water supply. At selected intervals along these pipes are independent, heat activated valves known as sprinkler heads. It is the sprinkler which is responsible for water distribution onto the fire. Most sprinkler systems also include an alarm to alert occupants and emergency forces when sprinkler activation (fire) occurs.


Automatic Fire Sprinklers During the incipient fire stage, heat output is relatively

low and unable to cause sprinkler operation. As the fire intensity increases, however, the sprinkler's sensing elements become exposed to elevated temperatures (typically in excess of 135-225F/57-107C)and they begin to deform. Assuming temperatures remain high, as they would during an increasing fire, the element will fatigue after an approximate 30 second to 4 minute period. This will release the sprinkler's seals allowing water to discharge onto the fire. In most situations less than 2 sprinklers are needed to suppress the fire. In fast growing fire scenarios such as a flammable liquid spill, up to 12 sprinklers may be required for control.


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HEAD is pressurised by Fresh water

BULB keeps valve closed.

Heat causes alcohol inside bulb to expand, shatter bulb and water flows.


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FRESHWATER SPRINKLER SYSTEM


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SPRINKLER HEADS The different colours denote different operating temperatures, but the alcohol is the same, only the size of the air bubble changes.


Standard Sprinkler Head Styles


Automatic Fire Sprinkler System


Automatic Fire Sprinkler System

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Fire Pump & Jockey Pump Mohd. Hanif Dewan, Senior Engg. Lecturer, International Maritime Academy, Bangladesh

Automatic Fire Sprinklers


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Typical low pressure sprinkler system NOT HIGH FOG


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EXPANSION

Supply for up to 200 sprinkler heads


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HIGH FOG Cool and smother, using the latent heat properties of water to cool, and expansion into steam to temporarily remove oxygen. Devised by Marioff, from an initial requirement by the Belgian air force, Marioff converted a hydraulic system of 200 bar pressure to water in 1974. Development then followed on head technology, and pressures have reduced drastically. The following slide shows a GL approved hi fog system currently fitted to new build container ships. A single stage low pressure centrifugal pump, with a screw inducer fitted in the eye takes suction direct from the domestic fresh water tank.


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The detail shown right, features the pump taking suction from the fresh water tank. The system is manually operated locally or remotely. Pump is fed via EMS. All operations are controlled by one panel, opening valves and starting pump.


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Hi Fog droplets are extremely small, increased surface area causes them to flash into steam, latent heat is absorbed, steam generated displaces oxygen.

FOG

SPRINKLER-DROPLETS


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SMOTHERING Removal of Oxygen FOAM Simple foam installation,with seawater mixing with foam compound(usually protein). Not much to go wrong!


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A simple CO2 driven foam system


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Exact metering of foam compounds and water.


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Types of foam available for marine use: 1. Protein base ( PF) 2. Flouro protein foam (FP) 3. Film forming fluoro protein foam (FFFP) 4. Synthetic detergent foam 5. Alcohol resistant foam-chemical fires 6. Aqueous film forming foam ( AFFF)


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Hi-Ex-limited use due to lightness of foam-convection currents easily blow the foam away.Must be delivered from overhead nozzles However you can breathe in the mixture, and there is a limited cooling and smoke clearing effect.


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SMOTHER INERT GASES to TEMPORARILY or PERMANENTLY remove OXYGEN from the seat of the fire Temporary-discharge of CO2 from storage Permanent-use of Inert gas generator to blanket a space or cargo tank.


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0 5 10 15 20

5

10

15

20

% O2 in mixture

% hy

dro

carb

on

ga

s in

th

e

mix

ture

Inflammable zone

10%

2%

Inert


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The flammable range is relatively narrow, so that any new gas introduced into the space will either displace oxygen or remove hydrocarbon vapours. This particular example is for crude oil, but the principle applies to all hydrocarbon based fuels.

0 5 10 15 20

5

10

15

20

% O2 in mixture

% hy

dro

ca

rbo

n ga

s in

th

e

mix

ture

Inflammable zone

10%

2%

Inert


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In the case of discharge of CO2, the energy released as the CO2 expands, plus the smothering action of the CO2, plus the smothering action of smoke, temporarily removes the O2 content below 10%. Note that human life may be extinguished at any level below normal oxygen level

0 5 10 15 20

5

10

15

20

% O2 in mixture

% hy

dro

ca

rbo

n ga

s in

th

e

mix

ture

Inflammable zone

10%

2%

Inert


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In the case of inerting hydrocarbon cargo tanks, inert gas is produced from a combustion unit, so that O2 content is typically 5%. This is used initially to remove the fuel vapour, and then permanently to reduce O2 content during loading/unloading operations.

0 5 10 15 20

5

10

15

20

% O2 in mixture

% hy

dro

ca

rbo

n ga

s in

th

e

mix

ture

Inflammable zone

10%

2%

Inert


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CO2 Fixed Fire Extinguishing System for Machinery Space


CO2 System operation in Machinery Spaces A Co2 system of machinery spaces consists of a bank of Co2 bottles that can be operated from a remote place located away from the machinery spaces. The system also consists of pilot Co2 cylinders which control the activation of the bank of Co2 bottles. The Pilot cylinders are contained in a control box and are normally kept disconnected. The system is connected to the pilot cylinders and the control box with the help of steel wires or flexible pipes. All these pipes are fitted with a quick action coupling. When the system is to be activated, the coupling in plugged into the corresponding socket. The valves of the pilot cylinders will be opened with the help of the levers in the main CO2 control system. - The CO2 from the pilot cylinders will open the system's main stop valve. - The main stop valve has a piston which gets depressed due to the Co2 gas pressure and allows the pilot gas to flow to the bank of CO2 cylinders. - This pilot gas operates the cylinders' valves. These valves are known as Klem valves. All these valves have an actuator which gets operated by the pilot pressure.


- The detection of fire is done by various sensors installed in the machinery spaces.Though the opening of control box operates an alarm, the main decision for CO2 flooding is taken by the Chief engineer, after due consultation with the master of the ship. - Before releasing Co2 into the fire affected space, it should be made sure that everybody is out of the place and total head should be counted. - The place is fully enclosed i.e all skylights & ventilators are closed air-tight and pumpsumps supplying fuel oil should also be stopped in order to prevent re-ignition. - Separate levers for each and every space are present inside the main controlling cabinet. The operating of a particular lever activates the pilot bottles, which helps in releasing the complete bank of bottles designated for that place. - With the opening of the master valve, Co2 is flooded inside the fire affected space, which then smothers the fire with the help of blanket effect. - Boundary cooling should be carried out.


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The mass of CO2 required is defined under a typical calculation as shown.

This calculation is for a container ship, and is for a multi purpose system to cover a number of spaces.

The mass carried is sufficient to extinguish a fire in the largest space.


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THE FOLLOWING THINGS TO BE CONSIDERED: 1. The mass of CO2 required obviously has to take up free space i.e. air

space in the area protected. An allowance is made for machinery (and in this case, containers in the cargo hold) taking up space. The mixing ratio allows for this difference in permeability.

2. Having calculated the volume required, the mass is now estimated and this is translated into number of 45Kg or 48Kg bottles needed to protect each space. A multi purpose release system is now used to discharge the correct number of bottles for each space. One spare bottle ( for the total system)is required.

3. Obviously the release mechanism has to be robust and reliable. A pilot system is used to initiate the main release of bottles. The amount of CO2 in the pilot system is not counted in the calculation.

4. CO2 release must be used in conjunction with other measures: -Ventilation must be stopped, and - ventilation flaps closed, to prevent CO2 escaping from the space. - Quick closing valves are usually shut, to restrict supply of hydrocarbon fuels, so all Main and power generation engines will be stopped.


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5. Consequently the vessel is helpless and you must summon help. In addition, CO2 is a one shot system and if it does not work quickly IT WILL NOT WORK AT ALL. CO2 must be discharged as one MASS discharge, not individual bottles, and within two minutes of proven evacuation.

There are strict rules to be observed about releasing CO2 into a space and about re-entering the space afterwards.


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The system shown features both pilot and smothering bottles. Amount of pilot a gas DOES NOT feature in the calculation.

In this German flag, GL approved system, there is a built in time delay of about 24 seconds between operating the main bottle release and CO2 discharge


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Release cabinets for the ER system are located outside the engine room door and in the CO2 room. Release cabinets for the hold system are located on the bridge and in the CO2 room


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When the cargo hold system is discharged, ventilation is stopped and the correct amount of bottles for each hold is AUTOMATICALLY released


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GERMAN FLAG, GL approved system!!


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A method of storage developed in the 1980s was the use of refrigerated low pressure storage in a single container rather than ambient high pressure storage in large amounts of bottles. A second discharge is available by using the hot gas from the refrigeration circuit to boil the remaining CO2 gas out.

Capacity is 105% of storage space in a cold discharge


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Safe use of CO2 :- Ventilation fans off, space sealed, machinery stopped, tanks isolated. Total head count. CO2 released on masters command. Boundary cooling set up. Space remains sealed until steady temperature drop recorded over a period of 2 hours.

Safety of Re-entry: B.A. team re-enter machinery space and damp down hot spots. Re-entry should be from the top entrance. Ventilation fans restarted (extraction fan). Atmosphere tested with O2 meter throughout space Boundary cooling should be continued to stop re-ignition


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Cargo and container ships monitor the holds using a smoke extraction system, that removes the atmospheric contents of the hold, and passes the sample through a detector located in the wheelhouse.


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In the event of a smoke alarm, the ventilation system is stopped and the three way sampling cocks are turned to discharge CO2 back through the sampling pipes to the hold.

CO2 is released as required.


Co2 System for Cargo Space The release mechanism of CO2 system in cargo spaces is same as that of the machinery spaces. The only difference is that the cargo spaces have a different type of fire detection system. For detection of fire in cargo hold, a sample of air is drawn from all the cargo holds by an extractor fan.This sample of air is passed through a cabinet wherein a set of smoke sensitive sensors analyze the sample. The sensors will detect any presence of smoke in the sample. As soon as the sensor detects smoke in the sample, it activates the CO2 alarm system of the ship. A part of the sample is also discharged to the wheelhouse in order to cross-check the presence of smoke in the sample. This can be done by smelling the smoke. The sample is later vented to the air. In order to check whether the extractor is extracting samples from the holds, a small indicator propeller is fitted, which ensures that the samples are taken.


Checks on the CO2 system: i. Pipes leading to the spaces should regularly be blown with air to ensure that they are not blocked. Ii. The level in the Co2 bottles should be checked on regular basis. If in a particular check, the difference is 10% of the total volume, the bottle should be replaced as soon as possible. Iii. Sensors should be checked periodically. Iv. Cabinet door alarms should also be checked on regular interval of time. V. All the pipings and connections at the CO2 bottles should be checked regularly.


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OTHER METHOD OF SMOTHERING OF FIRES: Smothering of a fire can also be achieved by using inert gas

produced on board ship. In this case the inert gas is produced as required, and is low

pressure NITROGEN, which is the leftover by product of combustion, as long as the Oxygen content is consistently less than 10% maximum.

Effectively this rules out diesel engines and incinerators and leaves 1. Exhaust gases from a Marine boiler 2. Exhaust gases from a purpose built combustion unit 3. Exhaust gases from the AFTERBURNER of a gas turbine.


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MAIN BOILER


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MAIN BOILER


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System using exhaust gases from a boiler on load producing steam


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This unit, sometimes called an autonomous unit, burns diesel oil to generate a very low oxygen content in the exhaust gases

It has no other function and is very useful when there is an an instant demand for inert gas- topping off.


The Oxygen Depleted Condition

No Fire can take Place even in the presence of Heat or Fuel because there is not enough oxygen to support it

Safe Ship

NO FIRE

In absence of any one side of the original Fire Triangle, the risk of a fire is non-existent.


The Flammability diagram

8 %

Inerted Condition


The percentage of oxygen required to sustain combustion:

More than 11 %

What percentage of oxygen are required to maintain in the cargo tanks ?

By law less than 8 %. Some ports require a vessel to maintain less than 5 %.

A Cargo tank is considered Inerted when the oxygen content in the tank is less than 8 % by volume


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CHAINBREAKERS HALON

Still legal under IMO legislation but not UK legislation ( or other

EU countries plus CANADA) NOVEC 1230 is an approved

drop in replacement.


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CHAINBREAKERS Originally only Halon, ( see MGN 258). Alternative environmentally friendly gasses now available include:- Novec 1230. FM200. Halotron 11 B.

These gasses act by blanketing (excluding oxygen at the seat of the fire) and cooling but some (NOVEC1230) also disrupt the chemical chain reaction of combustion.


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1. HALON is a CFC and so has the same OZONE depletion affect as R11 and R12. 2. NOVEC 1230 is a HALON replacement, using roughly the same pipeline layout, and same mass of fluid, with a slight change in head detail, and with an ODP and GWP of 0. 3. FM 200 AND HALOTRON 11 require roughly 1.5-2 times as much mass as HALON, with an ODP of 0 and a GWP of 1 4. PYROGEN has appeared briefly as a HALON substitute but has since disappeared. Dry powder is also a chain-breaker and in addition acts as a smothering agent.


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Water Foam Dry Powder CO2 Halocarbon

HAND HELD FIRE EXTINGUISHERS


Portable Fire Extinguishers

firemain and hose reel system

(manual actuation)


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Types of fire extinguishers

Different types of fire extinguishers are designed to fight different types of fire. The most common types of fire extinguishers are: Water extinguishers Foam extinguishers CO2 (carbon dioxide) extinguishers Dry chemical extinguishers Fire blanket

C/E HANIF DEWAN 157 Mohd. Hanif Dewan, Senior Engg. Lecturer, International Maritime Academy, Bangladesh

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WATER EXTINGUISHER

Extinguish fire by cooling the surface of the fuel to remove the "heat" element of the fire triangle.

It is designed for Class A (wood, paper, cloth, rubber, and certain plastics) fires only.


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WATER EXTINGUISHER

Important: Never use water to extinguish flammable liquid fires. Water is extremely ineffective at extinguishing this type of fire and may make matters worse by the spreading the fire.

Never use water to extinguish an electrical fire. Water is a good conductor and may lead to electrocution if used to extinguish an electrical fire. Electrical equipment must be unplugged and/or de-energized before using a water extinguisher on an electrical fire.


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Foam Fire Extinguisher

Modern synthetic AFFF offers a very effective means of extinguishing fires that involve

both normal combustible materials and flammable liquids. AFFF, which stands for Aqueous Film Forming Foam, extinguishes Class A fires by removing the HEAT and cooling the fire and Class A, B & C fires, by shutting off the OXYGEN and suffocating the fire.


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Foam Fire Extinguisher

With flammable liquids (Class B materials) , allow the foam to gently flow over the surface of the liquid moving the nozzle from side to side, until the fire dies down.

With most Class A materials, you will often find that although the flames have been extinguished, the materials will continue to smolder for quite some time, so it is important to make sure that any Hot Spots are completely extinguished, as the fire may re-ignite.


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Carbon dioxide extinguishers

This type of extinguisher is filled with Carbon Dioxide (CO2), a non-flammable gas under extreme pressure. These extinguishers put out fires by displacing oxygen, or taking away the oxygen element of the fire triangle. Because of its high pressure, when you use this extinguisher pieces of dry ice shoot from the horn, which also has a cooling effect on the fire.


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You can recognize this type of extinguisher by its hard horn and absent pressure gauge.

CO2 cylinders are red and range in size from five to 100 pounds or larger.

CO2 extinguishers are designed for Class B, C, E and F fires.


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Important:

CO2 is not recommended for Class A fires because they may continue to smolder and re-ignite after the CO2 dissipates.

Never use CO2 extinguishers in a confined space while people are present without proper respiratory protection.

Locations:

Carbon dioxide extinguishers will frequently be found in industrial vehicles, mechanical rooms, offices, computer labs, and flammable liquid storage areas.


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Dry chemical extinguishers Dry chemical extinguishers put out

fires by coating the fuel with a thin layer of fire retardant powder, separating the fuel from the oxygen. The powder also works to interrupt the chemical reaction, which makes these extinguishers extremely effective.

Dry chemical extinguishers are usually rated for class B and C fires and may be marked multiple purpose for use in A, B & E fires. They contain an extinguishing agent and use a compressed, non-flammable gas as a propellant.


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Dry chemical extinguishers

ABC fire extinguishers are red in color, and range in size from five pounds to 20 pounds.

Dry Chemical extinguishers will have a label indicating they may be used on class A, B, E & F fires.


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Fire Blanket

Fires in small utensils containing cooking fats can be extinguished by smothering with Asbestos blanket or door mat (which has been wetted first!). Normally use to extinguish class K type of fire.


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Using a fire extinguisher The following steps should be followed when responding to

incipient stage fire: Sound the fire alarm and call the fire department, if appropriate. Identify a safe evacuation path before approaching the fire. Do not allow the fire, heat, or smoke to come between you and your evacuation path. Select the appropriate type of fire extinguisher. Discharge the extinguisher within its effective range using the P.A.S.S. technique (pull, aim, squeeze, sweep). Back away from an extinguished fire in case it flames up again. Evacuate immediately if the extinguisher is empty and the fire is not out. Evacuate immediately if the fire progresses beyond the incipient stage. C/E HANIF DEWAN 169


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Using a fire extinguisher Most fire extinguishers operate using the following P.A.S.S. technique: 1.PULL... Pull the pin. This will also

break the tamper seal. 2.AIM... Aim low, pointing the

extinguisher nozzle (or its horn or hose) at the base of the fire. Note: Do not touch the plastic discharge horn on CO2 extinguishers, it gets very cold and may damage skin.

3.SQUEEZE... Squeeze the handle to release the extinguishing agent.

4.SWEEP... Sweep from side to side at the base of the fire until it appears to be out. Watch the area. If the fire re-ignites, repeat steps 2 - 4. C/E HANIF DEWAN 170


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FOUR METHOD OF FIRE EXTINGUISHMENT


Provision for fire protection Ship division - main vertical zones by thermal & structural boundaries Inert gas protection tankers Lockers combustible materials Use of flame retardant materials flame screens and other devices for preventing the flame passage Use of steel Provisions wrt fire main - diameter, pressure (SOLAS minimum requirement)


Basic principles

Division into main and vertical zones by thermal and structural boundaries Separate accommodation spaces from the remainder by thermal and structural boundaries Restricted use of combustible materials Fire detection in the origin zone Containment and extinction of any fire in the origin space Protection by means of escape / access for fire fighting purposes Readily available of fire-extinguishing appliances Minimise possibility of ignition of flammable cargo vapour


Bulkheads & decks

Divide vessel into number of separate divisions Heat / flame must penetrate before can spread to another compartment Constructed from approved non combustible material steel with appropriate strength But heat of intense fire can cause exposed steel to wrap, buckle or fail SOLAS & regulatory bodies have stringent rules on this construction


Class divisions Ability of composite materials which are used as

load-bearing "A" or "B" class divisions to withstand the applied loads during and at the end of fire Adopted by the Organization Additional tests on small specimens to determine the high temperature strength properties of the material. Formed by bulkheads, decks, ceiling, lining Non combustible materials capable preventing smoke and flame passage when subject to standard fire test for a specified duration


Non-combustible material Material which neither burns nor gives off

flammable vapours in sufficient quantity for self-ignition when heated to approx. 750C Determined to the satisfaction of the Administration by an established test procedure Any other material is a combustible material


Standard time temperature curve At the end of the first 05 min 556oC At the end of the first 10 min 659oC At the end of the first 15 min 718oC At the end of the first 30 min 821oC At the end of the first 60 min 925oC


A lass diisio ulkhead ad dek Constructed from steel or other equivalent material Suitably stiffened Capable preventing passage of smoke and flammable to the end of the one-hour standard fire test Insulated with approved non-combustible materials


A lass diisio ulkhead ad dek Average temperature of unexposed side will not rise

more than: 139C above the original temperature 180C at any point including any joint, above the original temperature

within the time listed below: Class A-60 60 min Class A-30 30 min Class A-15 15 min Class A- 0 0 min The Administration may require a test of a prototype (original sample) bulkhead or deck to ensure it meets the above requirement for integrity and temperature rise


B lass diisio ulkhead, dek, eilig o liigs) Constructed to capable preventing flame passage

until end of the first half hour of standard fire test Insulated so that average temperature of the unexposed side will not rise more than: 139C above the original temperature 225C at any point including any joint above the normal

temperature

within the time listed below: Class B-15 15 min Class B- 0 0 min 4/7/2014 181


B lass diisio ulkhead, dek, eilig o liigs ot/ Constructed of approved non-combustible

materials All materials entering into construction and erection of B class divisions shall be non-combustible The Administration may require a test of a prototype (original sample) division to ensure that its meets the above requirements for integrity and temperature rise


Main vertical zones Those sections which the hull, super structure and

deckhouses are divided by A class divisions mean length on any deck does not exceed 40 meters

Accommodation Spaces Spaces used for public spaces, corridors, lavatories, cabins, offices, hospitals, cinemas, games and hobbies rooms, barber shops, pantries containing no

cooking appliances and similar spaces.


Public Spaces Public Spaces are those portions of the accommodation which are used for halls, dining rooms, lounges and similar permanently enclosed spaces

Cargo Spaces Cargo Spaces are all spaces used for cargo, cargo oil tanks, tanks for other liquid cargo and trunks to such spaces

Closed Ro-Ro Cargo Spaces Spaces which are neither open ro-ro spaces nor weather decks


Ro-Ro Cargo Spaces Spaces not normally subdivided and extending

to either a substantial length or entire length of vessel in which motor vehicle with fuel in their tanks for their own propulsion and/or goods (packaged or in bulk, in or on rail or road cars, vehicles (including road or rail tankers), trailers, containers, pallets, demountable tanks or in or on similar stowage units or other receptacles) can be loaded and unloaded normally in a horizontal direction


Open Ro-Ro cargo spaces Spaces that either open at both ends, or have an

opening at one end, and are provided with adequate natural ventilation effective over their entire length through permanent openings distributed in the side plating or deck-head or from above, having a total area of at least 10% of the total area of the space side


Machinery Spaces of Category A (1 July 2002)

Spaces and trunks to such spaces which contain either: Internal combustion machinery used for main

propulsion Internal combustion machinery used for other than main propulsion where such machinery has an aggregate total power output > 375 kW (500 hp) any oil-fired boiler or oil fuel unit or equipment other than boiler, such as inert gas generator, incinerator, waste disposal units, etc


WATERTIGHT DOOR

4/7/2014 188 Mohd. Hanif Dewan, Senior Engg. Lecturer, International Maritime Academy, Bangla

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