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FireFire theorytheory
Terms and definitions
Fire
The process of combustion of inflammable materials producing heat and light and
(often) smoke
Refers to combination brilliant glow and large amount of heat during exothermic
oxidation
Flames are body of gas that releases heat and light
Starts when fuel subjected to energy source
Sustained by further release until combustible fuel is consumed
Flame
Red or yellow burning gas seen when something is on fire
Combustion
The process of catching fire and burning / chemical activity, usually in presence of
oxygen, that produces light and heat
Non-combustible material: neither burns nor gives off flammable vapours @ 750C
Energy
Different types
o Kinetic
o Potential
o Heat
o Mass
First law thermodynamics: energy can not be created, nor can it be destroyed
Energy transformed usually with exchange of heat
Basic principles
Transfer of heat
Conduction (5%) = transfer through solids throughout contact of molecules
Convection (75%) = transport due to movement
Radiation (20%) = transport by energy waves
Sparks can travel meters and start new fires
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Flashover
o Most dangerous time
o Entire room into flame => flashover occurred
o Caused by radiation feedback of heat
Heat absorbed into upper walls and contents of room
Heating up combustible gases and furnishings to auto-ignition
temperature
o Several major changes
End effective search and rescue
End using portable extinguishers
End growth stage
Change from content to structure fire
Beginning collapse danger
Mechanism of a fire
Oxidation
o Slow: rust
o Fast: fire
o Very fast: deflagration
o Immediate: explosion
Gas fire
o Molecules of gas collide
o Higher temperature => higher energy
o Chain reaction
o Molecule splits in atoms and free radicals => react other combustible molecule=> reacts with oxygen => oxidation liberates new atom or free radical =>
Liquids
o Vapour will combine
o Liquid fire = gas fire at surface of liquid
o Temperature rises => more vapours come off
Solid
o Start as gas fire
o PYROLYSIS
Thermal decomposition
Temperature high enough + enough oxygen => carbon will burn Formation of CO
Spontaneous combustion
o Material ignites without external source of heat
o Heat generated by
Oxygen in air
Absorption moisture
Processing
Radioactive decay
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Explosives
Accelerated or divided chain reaction => explosion
Mechanical
o No chemical reaction
o Ex: breaking of cylinder containing compressed gas Chemical
o Fast exothermic chemical reaction
o Ex: polymerisation
Division in
o Deflagration
Most common
Speed flames between 1 to 1000 m/s
Pressure no more than some bars
o Detonations
Supersonic speed
Between 1500 to 2000 m/s
Shock wave of15 to 20 bar
BLEVE (boiling liquid expanding vapour explosion)
o Tank with gas under pressure
o Liquid + gaseous vapour
o Rupture in tank => drop in pressure => overpressure from point of rupture
o Violent boiling of liquid => large amounts of vapour
o Also caused by external fire nearby storage heating op contents and pressure
build-up
Fire risk
Fire risk = probability of a fire * potential damage
Probability
o Construction and material
o Content of area
o Activities
o Personnel
o External risks
o Possible growth potential depends on structure, ship design & compartmenting Potential damage
o Duration fire
o Highest temperatures
o Amount combustible material
o Characteristics combustible materials
o Oxygen supply
Combustible charge
o Indication of amount of combustible material per surface or volume
o Mass * caloric potential
o Not direct indication for fire risk Possibility of ignition => frequency
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Fire growth speed => potential damage
o Little influence on maximum temperature
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Influence ventilation
o Ventilation controlled fire
Combustible charge large
Air supply limited
Ventilation increases => temperature rises => fire duration decreases
o Fuel surface controlled fire
Combustible charge limited
Air supply large
Ventilation increases => temperature decreases => no influence on
duration
o Temperature highest in transition between ventilation and fuel surface
controlled fire
Development of a fire
Ignitiono Temperature rises rather slow
o Development depend on
Amount combustible material
Ventilation
Smoke
Caloric potential
Rate of heat development
o Caused by different mechanisms
Often thermal
Electric discharge Electromagnetic radiation
Ultrasonic vibrations
Growth stage
o Combustible materials incorporated one by one => chain reaction
Fully developed stage
o Starts with flashover
o Whole room on fire
o Temperature keeps rising
Natural decay
o Starts when temperature at 80% of maximumo All combustible materials given their heat
o Temperature will drop
Vapour pressure
Pressure of vapour in equilibrium with non-vapour phases
Indication of liquids evaporation rate
Non-linearly relation
Boiling point = temperature where vapour pressure equals atmospheric pressure
The higher the vapour pressure, the lower the boiling point
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Flammability
Inflammability
o Indication on possibility of ignition
Flash point: enough vapour to allow ignition when mixed with air and
ignition source present, ignition source removed => fire extinguishes Fire point: see flash point but fire will continue burning
Self ignition temperature: ideal conditions, heated to initiate self-
sustained combustion independent of any ignition source
o NO correlation between flash point & self ignition temperature
o Two basic types flash point measurement
Open cup
Closed cup
Speed (depends on)
o Concentration
o Proportion different componentso Dimensions and contact surface
o Temperature (logarithmic scale)
Flammable / explosion limits
Gases & vapours only flammable within certain limits
LEL
o Minimum concentration
o Below: too lean
UELo Maximum concentration
o Above: too rich
Change with
o Temperature (higher temperature => wider explosion limits)
o Pressure
o Purity substance
o Presence inert gas will influence UEL
Difference UEL & LEL gives flammable or explosive range
Explosion diagram: seep. 22
Fire triangle fire tetrahedron
Fuel, oxygen, source of ignition (heat/energy)
Removal any side => extinguish fire
Removal oxygen
o Fire smother when oxygen level < 16%
o Not possible for substances containing own oxygen
o Means
Foam
CO2 Dry powder
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Water mist and fog
o Temporary effects
o Inerting preventive measurement
Removal heat
o Rate larger than that produced by fire
o Cooling boundary bulkheads reduces possibility igniting material outside
affected compartment (fire cube!!)
o Water best cooling agent
o Effect 6 times greater when steam
o Even more when fog
o Cut off power supply when using water
o Foam also good cooling agent
o Heat absorbed by decomposition of dry powder or from CO2 => rather small
Removal fuel
o Not always possible
o Liquid fire cause by leaking => supply closedo Drain burning tank
o Shut down supply in gas fire
o Combustible materials removed from fire and surrounding areas
Breaking chain reaction
o Heat should be removed too (re-ignition possible)
o Means
Dry powder
Halon
Aerosols
Smoke
Dangerous aspect
Consists of
o Soot
o Burned gasses
o Unburned gasses
Important negative consequences
o Loss of orientation
o Irritation airwayso Production toxic and asphyxiating gasses
o Heat
o Flammable due to incomplete combustion
o Development flashover & backdraft
Backdraft
If oxygen used faster then added => fire dies out
Unburned gasses remain
Breaking window/ door opened => fresh air => explosive combustion
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Fire classes
Class A: solid fires
Class B: liquid fires
Class C: gas fires
Class D: metallic fires
Class E: electrical fires (not in Europe)
Class F: fat fires
Causes of fireCauses of fire
Introduction
Most fires result of acts of crew
Carelessness, irresponsible behaviour & lack of knowledge => important causes
Careless smoking
Smoking in bed / smoking and alcohol
Fall asleep when smoking in bed => smouldering fire started by touching tobacco to
bedding => asphyxiation before discovery
Drinking alcohol => careless => left cigarette can be forgotten => small fire easily
developing when in contact with flammable material
Smoking in the engine & boiler rooms
Large amounts of petroleum products
Vaporise and mix with warm air
Lighted match / glowing tobacco can ignite flammable mix
Fires in oily rags
Smoking on board tankers
Smoking inside
Visitors dont know this => ask for their cigarettes
Smoking in cargo holds
Break-bulk cargoes vulnerable to cargo-hold fires during loading
Late discovery => much cargo involved
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Spontaneous ignition
Often overlooked
Example: oily rag => oxidises and produces heat => chain reaction
Clean and tidy ship best prevention Pyrophorus substances capable of taking fire on exposure to air
Faulty electric circuits and equipment
Standard equipment not adapted to circumstances on board
Easily corrode, break, heat up or give sparks
Deteriorated material = same problems
Improvised electrical connections & circuits can cause short circuits and overcharged
fuses
Heat of lighted electrical bulb can ignite combustible material by indirect contact
Hot work
Sparks & production of heat inevitable
Most frequently made mistakes
o Absence fire fighting equipment
o Presence combustible materials in surrounding area
o Dust or gas mixtures at working area
o No or incompetent safeguard
o Atmosphere not gas freeo Gas cylinders not vertical
o Damaged material
Hot work permit: only aid, no guarantee
Galley
Open flames and high temperatures + garbage oils & grease & intense activity
Extra attention to feep fat fryers, galley ducts (accumulated grease and dirt), towels
(dry above stove), improvised electrical equipment
GOOD HOUSEKEEPING
Engine room fires
Most common cause: oil leaking hitting hot spots
All surfaces above 220: shielded or insulated
GOOD HOUSEKEEPING
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Ship repair and dry dock
Reparations including hot work
Alarm systems / protective installations switched off
Shore personnel with other safety standards Water supply limited
Cargo
Physical & chemical properties differ from ship to ship, voyage to voyage
Extra problem: shore personnel
Fumigation canisters should not be forgotten
IMDG code
Prevent overflow
Other causes of fire
Lightning impact
Cathodic protection
Collision
Funnel sparks
Static electricity
PreventionPreventionIntroduction
Combination measurements to prevent & elements to limit consequences
Order of importance
o Prevention (separation elements fire triangle)
o Measures at management level (safety policy, permit to work)
o Group protection (isolation, structural boundaries)
o Individual protection (PPE)
o First aid (sufficient & efficient fire extinguishing material) Design & construction phase very important
Legislation
o Comply
o Only a minimum
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Legislation
SOLAS Chapter II-2 (7 parts, 20 rules)
FSS Code
o
Fire and Safety Systems Codeo 15 chapters
Chapter 1: General
Chapter 2: International shore connection
Chapter 3: Personnel protection
Chapter 4: Fire extinguishers
Chapter 5: Fixed gas fire-extinguishing systems
Chapter 6: Fixed foam fire-extinguishing systems
Chapter 7: Fixed pressure water-spraying and water-mist fire
extinguishing systems
Chapter 8: Automatic sprinkler, fire detection and fire alarm systems Chapter 9: Fixed fire detection and fire alarm systems
Chapter 10: Sample extraction smoke detection system
Chapter 11: Low location lighting system
Chapter 12: Fixed emergency fire pumps
Chapter 13: Arrangement of means of escape
Chapter 14: Fixed deck foam systems
Chapter 15: Inert gas systems
STCW related item
SOLAS chapter II-2 reg 2 Safety objectives
o Prevent occurrence fire and explosion
o Reduce risk to life
o Reduce risk of damage
o Contain, control and suppress fire and explosion
o Provide adequate & readily accessible means of escape
Following functional requirements
o Division ship
o Separation accommodation spaceso Restricted use combustible materials
o Detection in zone of origin
o Containment and extinction in space of origin
o Protection of means of escape and access for fire fighting
o Ready availability of fire-extinguishing appliances
o Minimization of possibility of ignition of flammable cargo vapour
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DetectionDetection
Introduction
2 types
o Automatic
o Non-automatic (intervention human)
Fulfil following requirements
o Reliable
o Sensitive (without false alarms)
o Not sensitive for normal changes of temperature or light
o Possibility to test
o Easy maintenance
SOLAS
o Fixed fire detection & alarm in
Periodically unattended machinery spaces
Machinery spaces where
Installation of automatic and remote control systems &
equipment approved in lieu of continuous manning
Main propulsion & associated machinery provided with various
degrees of automatic or remote control & under continuous
manned supervision from control room
o Accommodation, service spaces & control stations protected by fixed fire
detection & fire alarm system and/or automatic sprinkler, fire detection & fire
alarm system as follows, depending on protection method adoptedo Fire round after watch
Odour
Unused cabins open
o General fire alarm activated from the bridge (no detecting system => alerting)
Extra requirements on passenger ships
Automatic detection
Thermal detectors
o Thermostatico Thermo differential
o Rate of rise
Smoke detectors
o Photoelectrical
o Ionisation
Flame detectors
Electrochemical detectors
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Thermal detectors
Thermostatic detector
o Melting or dilatation of solid, liquid or gas
o Preset to fixed temperature (60 C 80 C )
o Often in combination with other types of detectors / extinguishing systemo Some with noise: gas filled ball bursts at set temperature
Thermo-differential detectors
o React to change of temperature (between 2 rooms / 2 areas in same room)
o Almost always used in combination with fixed heat detectors
Rate of rise detectors
o React to speed of temperature change
o Bi-metals
o Air volume in hemisphere
Combination detectors
Smoke detectors
Optical
o Quicker in detecting smoke by smouldering fires
o Light source, lens direct light into beam, photodiode or other sensor at angle to
beam
o No smoke: light passes in front of detector in straight line
o Smoke: some light scattered by particles => directing at sensor
o Often used in cargo spaces
Ionisationo Quicker in detecting smoke by flaming fires
o Two plates with voltage across, along with radioactive source of ionising
radiation
o Small amount of electrical current
o Smoke enters chamber => disrupts current => drop in current detected
o Amount radiation extremely small => only dangerous when inhaled
Flame detectors
React to presence of flames Uses optical sensors
Electrochemical detectors
Smothering fires most difficult to detect
o CO formed
o People die before raising alarm
Electrochemical sensor = self powered micro fuel cell
o Casing containing gel or electrolyte and 2 active electrodes
o Top of casing has membrane permeated by gas sample
o Oxidisation takes place at anode, reduction at cathode
o Current created
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o Gases which can be oxidized (like CO) sensed at anode
o Gases which are reducible (like oxygen) sensed at cathode
Detector location and number
Legal requirements
o SOLAS Detect fire in space of origin
Provide alarm for safe escape and fire-fighting activity
General requirements
o FSS
2 sources of power supply
Flame detectors only with smoke or heat detectors
Smoke detectors stairways, corridors & escape routes working at 2
12,5 % smoke density
Heat detectors 54C 78C or1 C rise per minute (except in drying
rooms) Testing possible at all times without renewal of any components
Location important (min 0,5 m away from bulkheads)
Max space between detectors also stipulated
o Automatic detection system give visible & audible signal in local compartment
o Location possible from the bridge (visible & audible)
o Special signal to inform malfunctioning
Fire characteristics
o Temperature rise & smoke density depend on material burning & ventilation
o Cargo space: develops slowly, linear temperature rise, thick smoke
o Engine room: fast temperature riseo Accommodation: temperature rises slowly, large amount of smoke
Detector sensitivity
o Smothering fires: optical detectors faster
o Flaming fires: ionic detectors faster
Distance between detectors
o Temperature decreases fast over7 meter
o Sensitivity very important within first 7 meter
Distance under hatch-coaming
o Cooling effect of coaming
o Highest temperatures => 5 10 cm under coaming Environmental conditions
o Reliability in different environmental conditions = important
o Humidity & other corrosive elements adversely effect reliability of sensors
Number of detectors
o Positioning remains difficult issue
o Often adapted after testing phase
o Unexpected air circulation or ventilation conditions affect functioning of
detector => might affect number of detectors
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Non-automatic detection
Call points
In accommodation, service spaces & control stations
Manually operated call point
Readily accessible in corridors of each deck so always within 20 m
Fire rounds
Great use in detecting fire
Fire risks observed & changed
Every officer after watch
ODOUR IS VERY IMPORTANT
Extra help from CCTV or surveillance cameras
ContainingContaining
Fire cube
Each compartment 6 adjoining areas
Each sides need to be controlled
o Removing combustible materials from walls
o Boundary cooling
o Safeguard posted at every side
Structural strength: fire resistance
Stability
Thermal isolation
Passage of smoke and flames
Standard fire test
Specimens of relevant bulkheads or decks exposed in test furnace to temperatures
corresponding to standard time-temperature curve in accordance with test method
specified in Fire Test Procedures Code
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Class divisions
A class (bulkheads & decks)
o Constructed of steel or other equivalent material
o Suitably stiffened
o Insulated with approved non-combustible materialso Average temperature unexposed side never more than 140 C above original
temperature
o Temperature never more than 180 C above original temperature
A-60: 60 minutes
A-30: 30 minutes
A-15: 15 minutes
A-0: 0 minutes
o Capable preventing passage of smoke and flame to end of one-hour standard
fire test
B class (bulkheads, decks, ceilings & linings)o Constructed of approved non-combustible materials except veneers
o Insulated
o Average temperature unexposed side never more than 140 C above original
temperature
o Temperature never more than 225 C above original temperature
B-15: 15 minutes
B-0: 0 minutes
o Capable preventing passage of flame to end of first half hour of standard fire
test
C classo Constructed of non-combustible materials
o Meet neither requirements relative to passage smoke & flame nor temperature
rise
o Combustible veneers permitted
FightingFighting
Introduction
Fire involves 4 elements
o Fuel
o Oxygen
o Energy
o Chain reaction
Removing one element extinguishes fire
o Removing fuel
o Suffocation
o Cooling fire
o
Interrupting chain reaction
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Extinguishing agents
Water
Working principle
o Cool down
o Produced vapour smothers fire
o Boundary cooling with water
o Injected as fog to form emulsion with oil to prevent oil from catching fire
Advantages
o Efficient
o Readily available
o Unlimited
o Cheap
o Non toxic
Disadvantages
o Water damage
o Stability
o Electric conductivity
o Can give dangerous chemical reaction
o Possible spreading class B fires
o Decomposition at high temperature feeds fire
Applications
o Best medium to extinguish class A fire
o Also for class B but can spread fire
o Boundary cooling
o Portable extinguishers
Not often on board
Almost always chemical added
o Main fire line
Provided with pumps, mains, hydrants & hoses
Avoid possibility of freezing
Suitable drainage provisions
At least 2 fire pumps & 1 emergency fire pump
Minimum capacity 25 m / h & supply 2 water jets
Two pumps simultaneously => following minimum pressures
> 6000 ton: 0,27 N / mm
< 6000 ton : 0,25 N / mm
Number & position so that at least 2 jets of water not emanating from
same hydrant, one from single length of hose, reach any part of ship
normally accessible for passengers / crew while navigating & any part
of any cargo space when empty
Fire hoses length at least 10 m, no more than
Machinery spaces: 15 m
Other spaces & open decks: 20 m
Open decks on ships with max breadth > 30 m: 25 m
Complete interchange ability of hose couplings and nozzles
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Diameter sufficient for discharge of140 m / h
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Nozzles approved dual purpose type
Jet
o Pressure can enlarge fire
o Cooling effect limited
o Smothering effect small
o Used to spread out class A fire
Spray
o Easily cool down fire
o Large amount of heat necessary to evaporate droplets
o Large amount of vapour will smother the fire
o Fixed water spray installation
To protect accommodation
o International shore connection
Ensure connection different ships & ship shore
At least one for every ship > 500 gross tonnage
Standard dimensions
o Sprinkler installation
Wet type (water readily available under pressure in the lines)
Combined with automatic detecting system
Ready for immediate operation
Min 2 sources of power supply for pump & alarm and detecting system
Resistant to corrosion & freezing
In operation between 68 C & 79 C
o Steam installation
Only on board tankers
Completely closed from outside air
Injected steam pushes oxygen away
Only small drop in temperature => danger for re-ignition
Extinguishing = rather slow
Damage by moisture & heat large
Water mist
Working principle
o Cooling
Removing heat because latent heat of vaporisation
Droplets enough momentum => penetrate the gases => absorb heat
from flame environment
o Oxygen displacement
Some water evaporates
Expands
Dilutes oxygen concentration by displacing air
o Radiant heat dilution
Suspended water vapour reduce radiant heat transfer between flame &
unburned fuel
Restrict fire growth & spread
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Advantages
o Fast
o Safe for people, environment & property
o Unlimited water supply
o No decomposition possible
o Minimal fire, smoke & water damage
o Minimal space & weight requirements
o Very efficient
o No electric conductivity
Disadvantages
o More expensive than fixed CO2 installation
o IMO restriction for volume difficulties to extinguish small fires in large spaces
Applications
o Replaces HALON
o Fixed installation
In machinery spaces & cargo pump rooms
Gains territory => also accommodation, service spaces, galleys &
laundries
o Piercing nozzle
High pressure water jet cuts small holes in door, wall, floor of word,
steel, concrete
Blows powerful mist into compartment
Cooling down
No opening of compartment => reduces risk of Backdraft
Foam
Working principles
o Cooling: 90 % water => vaporises
o Covering: prevent transformation to gas phase / lower vapour pressure
o Isolation: fuel separated from heat & oxygen
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o Different classes
o High quality foam
Attaches easily to form firm blanket
Stable
Flame suppressing
Heat resistant
Good flow
Fuel intolerance
o Two types class B flammable liquids
Non polar
Immiscible in water
Examples: gasoline, heptane, crude oil
Polar
Mixable with water
Examples: isopropanol, methyl ethyl ketone
All foams designed to be used on non-polar solvents but only polar
solvent / alcohol resistant concentrates effective on polar solvents
Some examples
o AFFF (Aqueous Film Forming Foam)
Contains fluoro-chemical surfactants
Control physical properties of water
On hydrocarbon liquid
o AFFF Polar
Contains pseudo plastic material
Forms polymeric layer only on polar solvents
On water soluble products
o Protein foam concentrate
Based on proteins with added chemicals
Exceptional stable, cohesive, heat resistant &
cheap
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Disadvantage: rather slow
Advantages
o Low expansion foam
Relatively cheap
Easy maintenance
o High expansion foam
Cheap
Easy application
Stable
Non toxic
Non asphyxiating
Escape through foam is possible
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Disadvantages
o Low expansion foam
Instable
Effectiveness deteriorates
Solution may crystallise
CO2 development may be dangerous in small enclosed area
o High expansion foam
Irritating for eyes and airways
Electrical conductive
Can cause important damage to equipment
Soluble in some products (can also be advantage)
Very light & can be blown away
Applications
o Portable extinguishers
Minimum capacity of9 litres
Most extinguishers mechanical foam
Foam forming product stored in separate container inside
extinguisher
Activating extinguisher => cylinder CO2 pierced
Water mixed with foam & CO2 before leaving
Expansion rate up to 1000
Chemical foam
Turn extinguisher upside down before use
Rare on board
Specific type for class F fires
Layer between burning grease and air
Cool down the product => temperature below self ignition
temperature
o Main fire line
Portable tank of min 20l + spare tank (FSS Chapt 4)
Nozzle capable of producing effective foam for extinguishing oil fire at
rate of at least 1,5 m/min (FSS Chapt 4)
Inductor connected to main fire line => Venturi effect mixes water &
product
To add air => aspiration holes
o Fixed installations High expansion
Capable of filling greatest space to be protected at rate of 1m in
depth per minute
Quantity available min 5 times volume of greatest space to be
protected
Expansion rate smaller than 1000
Low expansion
Discharging in 5 minutes a quantity of foam sufficient to cover
to a depth of 150 mm the largest single area over which fuel is
liable to spread Expansion rate smaller than 12
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Seldom used
Chemical powder
Working principle
o Inhibition Exact mechanism not understood
Remove chain reaction of fire tetrahedron
o Smothering
Layer between combustible and oxygen
o NO COOLING EFFECT => RE-IGNITION POSSIBLE
Advantages
o Not toxic
o Can be used neat electricity
o Used inside & outside
o Not dangerous to human life Disadvantages
o Damage to electrical & electronic equipment
o Can stick together when in contact with humidity
o Some react with water => corrosive products
o No cooling effect
Applications
o Mostly ABC powder, also BC powder and special D powder
o Sodium, potassium / ammonium phosphate base
o (semi) Portable extinguishers
Often powder stowed in extinguishers Min capacity of5 kg
Bottle of driving gas activated by opening valve / pushing pin
Distance of3 to 4 m
Directed to base of flames
Class A: shots of powder
Class B/C: continuous jet
Shake extinguishers before use
o Fixed installations
Powder stowed in air-tight compartment
CO2 stored in one or more cylinders connected to powder Lines made of rust proof steel & lead to discharge heads
Same flow from every head
After use, lines & heads can be flushed with air
Control of system: manual / automatic
Important: adequate detecting system => powder released in early stage
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CO2
Working principle
o Smothering
CO2 = inert gas
Lowers oxygen levelo Small cooling & blowing effect
CO2 snow released when product expands
Leaves with positive pressure => pushes flames away
Rather limited & negligible compared to smothering reaction
Advantages
o Easily available
o Covers fire
o No electric conductivity
o High rate of discharge
o No decompositiono No damage
Disadvantages
o Can cause thermal shock
o Danger of asphyxiation
o Expensive installation & use
o Special area for storage of fixed installation
o Less effective in open air
o Possibility of re-ignition
Applications
o Portable extinguishers Combat of class B fires
Easy & reliable
Approach fire to 1m
Before use, extinguisher must be tested
Hand at insulated handle
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o Fixed installation
Different components
CO2 cylinders
Collecting line
Switchboard
Lines connecting installation with area to be protected
Discharge valves
Mechanically / pneumatically / electrically
Area must be evacuated
Sometimes perfume added to alert in case of leaking
Installation requirements (FSS chapt 5)
Gas available at least certain percentage of volume to be protected &
85% injected in less than 2 minutes
o 30% cargo area
o 40% machinery areas
2 separate controls provided before CO2 is released
o Open valve of piping
o Discharge gas from storage containers
Sound alarm
Installation must be protected for over pressure
Never as a preventive measure!!
o N2 installation
Odourless, colourless & tasteless
Heavier than air
Only used in fixed installation
Must be as effective as CO2o Inert gas generator
Not toxic
Asphyxiating
Seldom used for fire fighting
Quantities needed higher than CO2
Applications more preventive
Fire blanket
Made of non flammable material Readily available in galleys
Smothering fire
NO COOLING DOWN
Sand
Prevent / combat beginning oil fire
Contain overflow
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HALONS
HALogenated hydrocarbONS
Forbidden as fire fighting agent because they attack ozone layer
Lot of alternatives
Inergeno Advantages
No ozone depletion
No evacuation needed
Non toxic to human health
Same density as normal atmosphere
Electrically non conductive
No fog created
o Disadvantages
Does not liquefy => more storage space needed
No worldwide coverage for refilling
Replacement of40 50 % of space needed in a short time to be
effective => creates large amount of pressure
Need for special area for storage of fixed installation
Less effective in open air
Possibility for re-ignition
Argonite
Novec 1230
New fire fighting products
Personal equipment
General
Components fire-fighters outfit (FSS code chapter 3)
o Breathing apparatus
o Protective clothing that protects from heat radiation & burns & outer surface is
water-resistant
o Boots of non conducting material
o Rigid helmeto Electrical safety lamp, min 3 hours burning period
o Safety line (min length 30m, fire proof, min strength 3,5 kN for 5 min)
Every ship at least 2 complete outfits with BA
Tankers 4 sets
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Respiratory protection
General
o Particles in the air
Solid compounds mixed with air
Small particles most dangerous
Damage to lungs / absorbed into blood chain
Dust, mist & smoke
o Gasses and vapours
Act similar to air & easily integrate into atmosphere
Long & short term health effects
Deadly concentrations / asphyxiation
Gasses formed at room temperature
Vapours are vaporised products
During cleaning, painting & using solvents
o Oxygen deficiency
At oxygen concentration < 19,5 %
Levels of oxygen deficiency
17%: increased breathing volume & higher heartbeat
14 16%: increased breathing volume, accelerated heartbeat,
poor muscular coordination, rapid fatigue & intermittent
respiration
6 10%: nausea, vomiting, inability to perform &
unconsciousness
< 6%: spasmatic breathing, convulsive movements, death
within minuteso Extreme temperatures
Cause lung damage
Self contained breathing apparatus
o Volume min 1200l / enough to be capable of functioning at least 30 min
o Theoretical consumption = 40l / min
o Consumption very personal
o Safety margin of50 bars
o Consists of
Fully adjustable harness
Compressed air cylinders Pressure reducing valve
Pressure gauge
Whistle warning unit (warning at 50 bars)
Medium pressure hose
Positive pressure facemask with instant demand valve
Closed circuit breathing apparatus
o Oxygen cylinder gives supply into breathing bag (mixed with exhaled air)
o Filter to dry and clean exhaled air
o Inhaled air feels very dry and warm
o Autonomy up to 2 hours Fresh air supply
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o Air supplied from outside toxic atmosphere
o NOT allowed on board
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Emergency escape breathing device
o Obligatory since July 2002
o Minimum 2 sets in accommodation area
o In machinery spaces: located directly for use at easily visible places
o Number & location indicated on fire control plan
o Minimum capacity of10 minutes
o ONLY FOR ESCAPE
Mask with filter
o Not used for fire fighting
o Doesnt supply oxygen
o Removes toxic components from the air
o Filter capacity = limited
Nominal protection factor
o Indication of protection given by mask
o The higher the NPF, the higher the protection
o NPF = concentration toxic air outside the mask / concentration toxic air inside
the mask
o Examples
Half mask with filter: 20
Full face mask with filter: 2 000
Mouth/nose clip with filter: 10 000
Full face mask overpressure: 50 000
Fresh air supply: 2 000
Fire control plan On strategic places on the ship
o Bridge
o Control room
o Every floor in accommodation
Watertight container near gangway
UPDATE THE PLAN
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EvacuationEvacuation
Legal requirements
In SOLAS chapt. II-2
Regulation 12: general emergency alarm system & public address system (available
throughout accommodation, service spaces, control stations & open decks) shall be
provided on every ship
Regulation 13: more info about means of escape (safe, accessible without obstacles &
clearly marked & illuminated)
o Accommodation
At least 2 means of escape
No dead-end corridors longer than 7m
EEBD available
o Machinery space At least 2 means of escape with self closing doors
EEBD available
Special requirements for passenger & ro-ro passenger ships
Aids to evacuation
Emergency signs
Continuous marking of escape routes with indications of direction
Posted at eye height
Low location lightning
Good visibility near the floor
Directions given with low location lightning
Photo luminescent material with pigment absorbing light & emitting over a period of
time
Pigment is rechargeable
Auditive signals
Directional sound directors
Necessary
o Timing (< 1 000 Hz)
o Intensity (> 3 000 Hz)
o Direction in relation to the head (> 5 000 Hz)
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Crowd and crisis management
Special training requirements for personnel on certain types of ships
Crowd reacts as follows
o 10% rescues himself
o 5% combats the emergencyo 10% will help
o 60% will wait for others to take initiatives
o 12 14% will freeze and do nothing
o 1 3% will panic heavily
Items of crowd management training
o Awareness of life-saving appliance and control plans including
Knowledge of muster lists & emergency instructions
Knowledge of emergency exits
Restrictions on use of elevators
o Ability to assist passengers Ability to give clear reassuring orders
Control of passengers in corridors, staircases & passage ways
Maintaining escape routes clear of obstructions
Methods available for evacuation of disabled persons & persons
needing special assistance
Search of accommodation spaces
o Mustering procedures
Importance of keeping order
Ability to use procedures for reducing & avoiding panic
Ability to use passenger lists for evacuation counts Ability to ensure that passengers are suitably clothed & have donned
lifejackets correctly
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Organisation / strategyOrganisation / strategy
Fire muster list
Similar to ship muster
Optimise chances of successful combat
Selection of members for parties done on basis of experience, physical condition, age
& knowledge
Each unit has specific duties
o Support party
Back up fire fighters with additional equipment
Stop spreading of fire
Preparing lifeboats & other life saving appliances
o Bridge party
Keep overall sight of situation
Directing of internal & external communication
Starting of fire pump
o Engine room party
Responsible for maintaining power supplies
Ensuring main engine available
Isolating affected electrical circuits & equipment
Ensure all fire pumps are fully operational
o Attack party
Fight fire
Asses situation & keep in contact with the bridge
Location nearby hazards
BA & protective clothing necessary
Fight / contain
Which apparatus
Direction of attack
o First aid team
Collects stretchers, blankets, first aid kit & resuscitator
Often join support team
FLEXIBILITY
Elements of command and control
Locating the seat of the fire
Can be very difficult
Rely upon heat & flames!
Stopping heat and fire from spreading
Ship conducts heat very well
Boundary cooling = essential
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Boundary starvation (often time consuming)
Containment
If fire cannot be beaten back / access impossible
Putting fire in fire cube
Ventilation
Ventilation control is one of most difficult challenges
Needs depend on stage of fire and way being fought
Ways of ventilation
o Position of vessel to take advantage of the wind
o Vertical ventilation
o Horizontal ventilation
o Assisted ventilation
Stability
Limit amount of water
Manage effects of water used
Keep scuppers clear
Guarding against re-ignition
Particular with class A fires
Watch of 24 hours in area after extinction Other areas should be searched for hidden pockets of fire
Fire drills
SOLAS
Planned so that consideration given to regular practice in various emergencies
Include
o Reporting & preparing for duties
o Starting fire pump, using at least 2 jets of water
o Checking firemans outfit & other personal rescue equipmento Checking relevant communication equipment
o Checking operation watertight doors, fire doors, fire dampers & main inlets &
outlets of ventilation systems
o Checking necessary arrangements for subsequent abandoning of ship
Equipment used immediately brought back to fully operational condition
On-board training not later than two weeks after crew member joins the ship
Instructions in use of fire-extinguishing & life-saving appliances at same intervals
Recorded in logbook
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Pre-fire survey form
Contains information pertinent to fire response in any given space
Combination of forms gives comprehensive reference overview of vessel
Not compulsory on board
Flashover
Indicates transition between growth stage & fully developed stage
Delay flashover in 3 ways
o Venting
Release build up of heat
Slows down flashover
Improving visibility in smoke-filled room
o Not venting Starve fire of oxygen
Slows down combustion rate
Slows down build up of heat
Done when delay in stretching a hose & all persons out of the burning
room
o Portable extinguisher
Discharge can cool heat down
Warning signs
o Heat
Mix heat & smoke => forces fire-fighter to crouch down
o Rollover
Sporadic flashes of flame mixed with smoke at ceiling level
Caused by heated combustible gases in smoke
Ignites into flashes of flame when mixed with oxygen
Precedes flashover
Smoke coming out of tops of doorways or window openings
Attack
o Using fire hoses
o Point to ceiling above with short pulses water, slowly descending to base of
fire
Backdraft
Limited ventilation => fire in compartment producing fire gasses containing
significant proportions of partial combustion products and un-burnt pyrolysis products
Sudden ignition when this accumulates and air is let in
Some indicating signs
o History of the fire (died from oxygen starvation)
o Holes and doors (smoke pulsing out, whistling noise)
o Door and handle are hot No prevention for backdraft
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Backdraft can be delayed!
Entry
General techniqueo Min 2 people
o Stay together
o Use breathing apparatus handle as connection
o Largest person first
o First = leader
o Good communication
o In touch with fixed object
o Memorise route & take same way back
o Count doors
o Count steps
o Follow same hand throughout complete entry
Reasons
o Search a fire (close to the walls)
o Search a victim (all areas inspected in systematic way)
Moving forward
Back of the hand to screen wall
Hand up & down
Other hand screen for obstacles
Weight on foot closest to the wall
Other foot to check for ground stability & obstacles
Opening a door
General
o Check temperature door handle
o Look for hinges to know opening direction
Opening towards you
o Door protect you
o Kneelo Foot against door
o Open few cm
o Enter when all clear
o Close door, if door handle exists
Opening opposite side
o Wall protect you
o Kneel
o Open few cm, remove hand
o Enter when all clear
o Close door, if door handle exists
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Stairs
More stable at sides than in middle
Check every step for stability
Downstairs => backwards
Searching for the floor
Contact to fixed object as wall or wardrobe
Tactical guidelines by type of vessel
Bulk and break bulk vessels
Spontaneous ignition
Dust explosion Fire detection delayed due to size & configuration of the vessel
If fire occurs, trying to limit the damage
Actions
o Boundary cooling
o Determine best extinguishing procedure for cargo type
o Fill wing tanks & double bottoms with seawater (displace vapours & improve
stability)
o Cooling streams over hatch covers
o Flood or soak burning material but consider following issues
Steam explosions Water reactive material
Swelling or expanding of wet cargo
o Close hold & proceed to nearest appropriate port for handling cargo
o Monitor temperatures in adjacent compartments
o Activate fixed fire suppression system if available
Check proper discharge
Allow adequate soaking time
Monitor interior conditions & temperatures
Often impossible to extinguish bulk fire (class A fires)
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Container vessel
Difficult access situation
Multiple cargoes & dangerous goods
Smoking containers treated as having large fire potential
Actionso Identify cargo in affected & surrounding area
o Isolate hold/cell, secure openings
o Fixed fire suppression system
o Fire boundaries & inert adjacent spaces
o Proceed to nearest port
Above hatches
o Make access if possible
o Manoeuvre vessel to advantage of fire teams
o Cool containers on all 6 sides
o Piercing nozzles dangerous if content is unknown
RO/RO, car carrier and ferry fires
Vehicle fires
Large open decks
Ships stability = major consideration
Cars themselves serious fire problem
Hydraulic systems can change into 3 dimensional spray => slip hazard
Small fires
o Portable fire extinguisher to control fire in individual vehicleso Pre establish an escape path
o Provide backup fire hose teams
o Keep ventilation running
o Alert for potential running fire
o Disconnect batteries of burned vehicles
o Use absorbents to control fuel, lubrication oil & transmission fluids spills
o Approach from upwind
o Stay clear of air bags & shock absorbers
Medium fires
o Easiest way to access burning vehicles (advancing dry hoses easier)o Keep ventilation running & monitor situation
o Apply short bursts of agent & reassess
o Consider use of fixed fire suppression systems
Large fires
o Confine the space
o Shut of all ventilation & power supply
o Evacuate passengers
o Follow procedures for use of fixed fire suppression systems
o Control stability!!
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Passenger vessel fires
Large life safety problem
Large scale fires
Most important responsibility = management of people / crowd control
Tanker fires
Commonly class B
Hazardous materials / toxic cargoes
Specific procedures must be followed
Gas carrier fires
Release of large vapour clouds