FIRE TRIANGLE: IF ANY ONE SIDE OF “FIRE TRIANGLE” IS REMOVED, FIRE WILL BE EXTINGUISHED.
METHODS OF FIRE FIGHTING: THERE ARE FOUR METHODS OF FIGHTING FIRE
- SMOTHERING – REMOVING THE AIR.
- STARVING - REMOVING THE BURNING MATERIAL FROM THE SURROUNDING.
- COOLING – REMOVING THE HEAT.
- INHIBITING – RETARDATION OF THE COMBUSTION REACTION.
Types of fire
In the European Standard "Classification of fires" (EN 2:1992, incorporatiing amendment A1:2004), the fires are classified as:
Class A fire: Ordinary combustibles such as wood, paper, carton, textile, and PVC;
Class B fire: Flammable liquids and solids which can take a liquid form, such as benzene, gasoline, oil;
Class C fire: Flammable gases, such as butane, propane, and natural gas;
Class D fire: Combustible metals, such as iron, aluminum, sodium, and magnesium;
Class F fire: Cooking media, such as oils and fats, in cooking appliances;
A fire involving energized electrical equipment is not classified by its electrical property.
SMOTHERING
IF THE OXYGEN CONTENT OF THE ATMOSPHERE IN THE
IMMEDIATE NEIGHBORHOOD OF BURNING MATERIAL CAN BE SUFFICIENTLY REDUCED
COMBUSTION WILL CEASE. THIS PRINCIPLE IS INEFFECTIVE IN THE CASE OF
CELLULOID AND SIMILAR SUBSTANCES, WHERE BURNING OF THE MATERIAL CONTAINS
WITHIN ITSELF, IN A CHEMICALLY COMBINED FORM.
PRACTICAL ASPECT: ON A SMALL SCALE IT IS EMPLOYED IN A SNUFFING CANDLE. PERSONS CLOTHING CAN BE SMOTHERED WITH A RUG / BLANKET
ON
A LARGE SCALE, IN CAPPING A BURNING WELL. BATTERING DOWN OF A SHIP’S
HOLD WHEN A FIRE BREAKS OUT BELOW DECKS WILL OFTEN HOLD THE FLAMES IN
CHECK UNTIL PORT IS REACHED.
PRACTICAL APPLICATION OF SMOTHERING METHOD
- USE OF FOAM: THIS FORMS A VISCOUS COATING OVER THE BURNING MATERIAL AND LIMITS THE SUPPLY OF AIR.
- USE OF DRY POWDER: SODIUM BICARBONATE FROM A
PRESSURIZED EXTINGUISHER. CARBONATE WHEN FINELY DIVIDED ABSORB HEAT AND
THUS HAS COOLING AND FLAME INHIBITING EFFECT.
- USE OF INERT GAS: THE VIGOROUS DISCHARGE OF INERT GAS,
SUCH AS CARBON DIOXIDE & NITROGEN IN THE IMMEDIATE VICINITY OF THE
FIRE REDUCES THE OXYGEN CONTENT OF ATMOSPHERE BY PROVIDING A TEMPORARY
BLANKET EFFECT.
STARVATION
THE EXTINCTION OF FIRE BY STARVATION IS APPLIED IN
THREE WAYS. BY REMOVING COMBUSTIBLE MATERIAL FROM THE NEIGHBORHOOD OF
THE FIRE.
Ex: DRAINING OF FUEL FROM BURNING OIL TANKS, DISCHARGING OF CARGO AT A SHIP FIRE.
BY REMOVING THE FIRE FROM THE NEIGHBOURHOOD OF COMBUSTIBLE MATERIAL.
Ex: PULLING APART A BURNING HAYSTACK.
BY SUB-DEVIDING THE BURNING MATERIAL.
Ex: SMALLER FIRES PRODUCED MAY BE EXTINGUISHED MORE EASILY, SUCH AS EMULSIFICATION OF THE SURFACE OF BURNING OIL.
COOLING
THE PROCESS OF REMOVING THE HAET FROM FIRE IS CALLED COOLING. THIS
IS NORMALLY DONE BY WATER, AS WATER HAS MORE COOLING EFFECT AND VERY
HIGH LATENT HEAT. APPLICATION OF JET OR SPRAY OF WATER TO A FIRE, EMULSIFICATION OF THE SURFACE OF OIL BY MEANS OF THE EMULSIFYING TYPE OF SPRINKLER HEAD.
INHIBITING
IN
THIS HEAT PRODUCING CHEMICAL REACTION OF SUBSTANCES IS CHECKED OR
STOPPED. THIS APPLIES TO ONLY FLAMING MODE AND NOT TO THE GLOWING MODE.
IN THIS FLAME INHIBITING EXTINGUISHING MEDIUM INTERFERES WITH THE ACTIVE
SPECIES IN FLAME CHAIN REACTION WHICH WOULD OTHERWISE FUNCTION AS
“CHAIN CARRIERS”. THIS METHOD EXTINGUISHES THE FLAME VERY RAPIDLY.
Ex: DCP OR HALON GAS – THESE ACT BY CHEMICAL INTERFERENCE WITH THE CHAIN REACTION OF FLAME PROPAGATION.
PROPERTIES OF FLAMMABLE MATERIAL
FLAMMABILITY: THIS
IS THE ABILITY OF SUBSTANCE TO BURN. IN THIS VAPOR GIVEN OFF BY
FLAMMABLE MATERIAL CAN BURN WHEN MIXED WITH AIR IN THE RIGHT PROPORTION
IN THE PRESENCE OF AN IGNITION SOURCE.
IGNITION POINT: IT IS THE LOWEST TEMP., TO WHICH A FLAMMABLE SUBSTANCE MUST BE HEATED TO IGNITE.
FLASH POINT:
IT IS THE LOWEST TEMP., AT WHICH THE VAPOUR OF THE SUBSTANCE ARE
AVAILABLE IN SUFFICIENT QUANTITY TO PRODUCE A MOMENTARY FLASH WHEN A
FLAME IS APPLIED.
FIRE POINT: IT IS THE TEMP.,
AT WHICH THE HEAT FROM THE COMBUSTION OF BURNING VAPOR IS CAPABLE OF
PRODUCING SUFFICIENT VAPOUR TO ENABLE COMBUSTION TO CONTINUE.
SPONTANEOUS / AUTO / SELF IGNITION TEMP:
IT IS THE LOWEST TEMP., AT WHICH THE SUBSTANCE WILL IGNITE
SPONTANEOUSLY i.e., THE SUBSTANCE WILL BURN WITHOUT THE INTRODUCTION OF A
FLAME OR OTHER IGNITION SOURCE.
UPPER FLAMMABLE LIMIT: IT IS THE CONCENTRATION OF FLAMMABLE VAPOUR IN AIR ABOVE WHICH THE MIXTURE BECOMES TOO RICH TO IGNITE AND PROPEGATE COMBUSTION.
LOWER FLAMMABLE LIMIT:
IT IS THE CONCENTRATION OF FLAMMABLE VAPOUR IN AIR BELOW WHICH THERE IS
INSUFFICIENT FLAMMABLE VAPOUR TO SUPPORT AND PROPAGATE COMBUSTION.
STATIC ELECTRICITY:
IT IS THE ELECTRICITY PRODUCED IN DISSIMILAR MATERIALS THROUGH PHYSICAL
CONTACT AND SEPARATION i.e., A SAMPLING APPARATUS LOWERED IN TO A TANK
CONTAINING CHARGED PETROLEUM LIQUID.
FLAMMABLE RANGE: IT IS THE RANGE OF CONCENTRATION OF A FLAMABLE VAPOUR IN AIR WITH WHICH THE VAPOUR AND AIR MIUXTURE IS FLAMABLE.
FLAMMABILITY: IT
IS THE ABILITY OF SUBSTANCE TO BURN VAPOUR GIVEN OFF BY A FLAMMABLE
MATERIAL, WHEN MIXED WITH AIR IN RIGHT PROPORTION IN THE PRESENCE OF THE
IGNITION SOURCE. NORMAL AIR CONTAIN - 21% OF O2 AND 78% OF N2 AND
SMALL TRACES OF CO2 , WATER VAPOUR etc. IN CARGO TANKS AS THE PERCENTAGE
OF HYDROCARBON INCREASES, OXYGEN CONTENT DECREASES.
LOWER FLAMABLE LIMIT (LFL): FOR
A MIXTURE OF AIR AND THE FUEL TO BE COMBUSTIBLE, MINIMUM QUANTITY OF
THE FUEL VAPOUR SHOULD BE PRESENT IN THE MIXTURE. THIS IS EXPRESSED AS
PERCENTAGE OF FUEL VAPOUR IN THE MIXTURE OF AIR AND VAPOUR. THIS IS
CALLED LOWER FLAMABLE LIMIT. THE MIXTURE WILL NOT BURN UNLESS FUEL
VAPOUR CONTENT IN THE COMBUSTIBLE MIXTURE IS ABOVE LFL.
EVERY TYPE OF FUEL HAS DIFFERENT LFL.
POINT “F” – MINIMUM OF O2 REQUIRED FOR COMBUSTION ( 11% BY VOLUME).
LFL – LOWER FLAMABLE LIMIT
– 1% OF C2H2 AT POINT “A”
UPPER FLAMABLE LIMIT (UFL):
WHEN
THE PERCENTAGE OF FUEL VAPOUR IS INCREASED IN THE MIXTURE, THE
PERCENTAGE OF AIR AND HENCE THE PERCENTAGE OF OXYGEN REDUCES.
SINCE
THE OXYGENN CONTENT BELOW 11% IN THE MIXTURE DOES NOT SUPORT
COMBUSTION, A STAGE MAY BE REACHED WHEN THE PERCENTAGHE OF VAPOUR IN THE
MIXTURE IS SO HIGH THAT RESULTING PERCENTAGE OF OXYGEN IS TOO LOW TO
SUPORT THE COMBUSTION AND MIXTURE WOULD NOT BURN EVEN WHEN IGNITED. THIS
IS CALLED UPPER FLAMABLE LIMIT.
MIXTURE WILL NOT BURN IF THE FUEL VAPOUR CONTENT MORE THAN THE UFL.
UFL – UPPER FLAMABLE LIMIT
- 11% OF C2H2 AT POINT “B”
EVERY FUEL HAS A LFL and UFL AND THE PERCENTAGE OF FUEL VAPOUR RANGE BETWEEN BETWWEN THESE TWO LIMITS IS CALLED “FLAMABLE RANGE”
POINT
“A” – AT THE END OF BURNING IF THE PRODUCT OF COMBUSTION ARE ANALYSED,
IT IS FOUND THAT ALL OF C2H2 VAPOURS ARE CONSUMED, WHILE SOME “O2” IS
UNUSED AND STILL AVAILABLE.
POINT “B” – AT THE END OF BURNING, ON
ANALYSIS, IT IS FOUND THAT ALL OF “O2” IS CONSUMED AND SOME UNBURNT C2H2
IS STILL AVAILABLE.
SOURCE OF IGNITION (HEAT ENERGY)
- CHEMICAL HEAT ENERGY
- ELECTRICAL HEAT ENERGY
- MECHANICAL HEAT ENERGY
- NUCLEAR HEAT ENERGY
CHEMICAL:
- HEAT OF COMBUSTION
- HEAT OF PARTIAL OXIDATION
- SPONTANEOUS HEATING
- HEAT OF DECOMPOSITION (ONION, POTATO etc., IN CARGO HOLD)
- HEAT OF SOLUTION (MIXTURE OF TWO CHEMICALS)
- ELECTRICAL:
- RESISTANCE HEATING
- DI-ELECTRIC HEATING
- INDUCTION HEATING
- MECHANICAL:
- FRICTIONAL HEATING
- FRICTIONAL SPARKS
- HEAT OF COMPRESSION
CLASSIFICATION OF FIRE
FIRES
ARE CLASSIFIED ACCORDING TO THE TYPES OF MATERIAL WHICH ARE ACTING AS
FUEL. FIRES BURNING WOOD, GLASSFIBRE, UPHOLSTERY AND FURNISHINGS. FIRES
BURNING LIQUID SUCH AS LUBRICATING OIL AND FUELS. FIRES BURNING GAS FUELS SUCH AS LIQUIFIED PETROLEUM GAS. FIRES BURNING COMBUSTIBLE METALS SUCH AS MAGNESIUM AND ALUMINIUM. FIRES BURNING ANY OF THE ABOVE MATERIALS TOGETHER WITH HIGH VOLTAGE ELECTRICITY.
THESE
CLASSIFICATIONS ARE ALSO USED FOR EXTINGUISHERS AND IT IS ESSENTIAL TO
USE THE CORRECT CLASSIFICATION OF EXTINGUISHER FOR A FIRE, TO AVOID
SPREADING THE FIRE OR CREATING ADDITIONAL HAZARDS. MANY FIRE EXTINGUISHER WILL HAVE MULTIPLE CLASSIFICATIONS SUCH AS A, B and D
FIRE EXTINGUISHING AGENTS
CARBON DIOXIDE:
AT NORMAL TEMP., CO2 IS 1.5 TIMES HEAVIER THAN AIR. IT IS EASILY
LIQUEFIED AND BOTTLED. IT IS STORED UNDER PRESSURE OF 50bar IN STEEL
CYLINDERS. WHEN CO2 IS APPLIED TO FIRE, THE LIQUID CO2 BOILS OFF RAPIDLY
AS A GAS, EXTRACTING HEAT FROM THE SURROUNDING ATMOSPHERE. IT
EXTINGUISHES FIRE BY SMOTHERING i.e., BY DISPLACING OXYGEN. ABOUT 20-30 %
OF THE ATMOSPHERE SHOULD CONTAIN CO2 TO EXTINGUISH THE FIRE. CO2 IS
QUICK AND CLEAN, NON-TOXIC, DOES NOT HARM MOST FAFRIC AND DOES NOT
CONDUCT ELECTRICITY. SO IT CAN BE USED ON ELECTRICAL IT DOES NOT DAMAGE
EXPENSIVE CARGO OR MACHINERY. IT LEAVES NO UNDESIRABLE RESIDUE TO BE
CLEARED OFF AFTER USE. SO IT CAN BE USED TO EXTINGUISH FIRE IN CARGO AND
MACHINERY SPACES BY PROVIDING FIXED CO2 INSTALLATIONS.
ADVANTAGES OF CARBON DIOXIDE:
- NON-CORROSIVE.
- DOES NOT CONDUCT ELECTRICITY.
- LEAVES NO RESIDUE.
- EASILY AVAILABLE.
- NOT SUBJECTED TO DETERIORATION IN QUALITY WITH AGE.
DISADVANTAGES OF CARBON DIOXIDE:
- TOXIC AND HAZARDOUS TO HUMAN BEING.
- LITTLE COOLING EFFECT & DANGER OF RE-IGNITION IF AIR IS READMITTED IN ROOM.
- SOLID CO2 PARTICLES GENERATE SPARK DUE TO STATIC ELECTRICITY, SO UNSUITABLE IN OIL TANKERS
WATER: IT
IS MOST EFFICIENT , CHEAPEST AND READILY AVAILABLE MEDIUM. IT HAS A
COOLING EFFECT AND NO-TOXIC. IT ABSORBS HEAT AND EXPANDS TO 1700 TIMES
OF IT’S VOLUME TO PRODUCE STEAM WHICH HAS SMOTHERING EFFECT.
IT IS SAFE TO USE ON MOST OF THE FIRES, IT CAN BE EASILY DIRECTED OVER A CONSIDERABLE DISTANCES.
DISADVANTAGES:
- IT CONDUCTS ELECTRICITY.
- IT CAN CAUSE DAMAGE TO CARGO & MACHINERY.
- LOSS IN STABILITY OF SHIP WHEN USED IN LARGE QUANTITY.
FOAM:
IT
IS MOST SUITABLE FOR EXTINGUISHING FIRES INVOLVING FLAMMABLE LIQUIDS.
IT EXTINGUISHES BY FORMING A LAYER OF SMALL BUBBLES ON THE SURFACE OF
THE LIQUID PREVENTING FUEL FROM VAPOURISING AND RESTRICTING THE OXYGEN
SUPPLY TO IT.
IT IS INSOLUBLE IN MOST OF THE LIQUIDS AND LIGHT IN
WEIGHT, SO IT FORMS A BLANKET TO COVER THE SURFACE OF BURNING LIQUID AND
THUS EXTINGUISHES THE FIRE.
FOAM CAN BE GERATED BY MECHANICAL OR CHEMICAL MEANS.
MECHANICAL
FOAM IS GENERATED BY AGITATION OF A DILUTED FOAM COMPOUND SOLUTION IN
PRESENCE OF AIR. THESE COMPOUND INCLUDE SOAPS, GLUE AND WETTING AGENT
MIXTURES. CHEMICAL FOAM IS GENERATED BY MIXING AN ALKALI (SODIUM
BI-CARBONATE) WITH A SOLUTION OF ALUMINIUM SULPHATE, IN PRESENCE OF A
STABILIZER (i.e., SOAP) THIS PRODUCES SKIMMED BUBBLES CONTAINING CO2
“HIGH EXPANSION FOAM” HAS A VERY HIGH EXPANSION RATION OF AROUND 1000 TO
1 INSTEAD OF 8 TO 1 FOR STANDARD FOAM. THIS TYPE FOAM IS USED FOR
DEALING WITH CARBONACEOUS FIRES IN COMPARTMENTS WHICH ARE INACCESSIBLE
AND WHICH LEND THEMSELVES TO COMPLETE FLOODING OF THE COMPARTMENT.
DRY CHEMICAL POWDER:
WATER
CANNOT BE USED ON MOST FIRES AS IT CAN BE EXPLOSIVELY DISASTROUS. IN
VIEW OF THIS OTHER MEDIUMS ARE USED. CHIEF AMONG THEM IS DRY CHEMICAL
POWDER. IN THIS SODIUM BICARBONATE IS USED AS BASIS ALONG WITH ADDITION
OF METALLIC STEARATE AS WATER PROOFING AGENT. DRY CHEMICAL POWDER IS
EXPELLED FROM CONTAINER BY GAS PRESSURE.
IT IS ESPECIALLY
EFFECTIVE ON BURNING LIQUIDS SUCH AS LIQUIFIED GAS, OIL ESCAPING FROM
LEAKING LINES AND JOINTS. ON ACCONT OF IT’S UNIQUE ABILITY TO QUICKLY
STOP COMBUSTION OF GASES, CHEMICAL PRODUCTS etc., IT HAS BECOME MOST
POPULAR MEDIUM IN GAS CACCIERS AND TANKERS. DRY CHEMICAL POWDER IS
ELECTRICAL NON-CONDUCTOR , THUS IT CAN BE UTILISED ON FIRES INVOLVING
LIVE ELECTRICAL EQUIPMENTS. IT INHIBITS THE COMBUSTION REACTION.
Solas convention
The
International Convention for the Safety of Life at Sea (SOLAS) is an
international maritime safety treaty. It ensures that ships flagged by
signatory States comply with minimum safety standards in construction,
equipment and operation.
1974 version
The
intention had been to keep the Convention up to date by periodic
amendments, but the procedure to incorporate the amendments proved to be
very slow,As a result, a complete new convention was adopted in 1974
which includes all the agreements and acceptable procedures. Even though
the Convention was updated and amended numerous times, the Convention
in force today is sometimes referred to as SOLAS, 1974.
The
latest Convention in 1974 included the "tacit acceptance" procedure
whereby amendments enter into force by default unless nations file
objections that meet a certain number or tonnage.
Types of Bulkheads.
'A' Class Divisions
Class
differences "A" are the bulkheads and decks of steel or any other
equivalent material which is capable of preventing the passage of smoke
and flames to the end of the test standard of the hour of fire. They are
well reinforced. They are insulated with unauthorized combustible
materials so that the average temperature of the un-exposed side does
not rise above the initial temperature or temperature at any point above
140 ° C, including any junction, rise above 180 ° C above the original
temperature, Within the time, specified below:
"A-60" 60 minutes
"A-30" 30 minutes
"A-15" 15 minutes
"A-0" 0 minutes.
A
prototype or platform partition should be tested according to the
FireCode test procedure to ensure that it meets the above requirements
for integrity and temperature rise.
Class A fire protection doors
The
construction of the doors in the class A walls and the fastening means
in the closed position provides a fire resistance, such as the passage
of smoke and flames, as far as possible, similar to the bulkheads in
which they are located.
Class A fire-resistant doors, made of steel or an equivalent material.
In These doors should be capable of being opened and closed from each side of the bulkheadby one person only.
Fire
doors in main vertical zone bulkheads, galley boundaries etc., other
than power operated water tight doors should be (1) self closing and and
be capable of safe operation with an angle of inclination of upto 3.5
degrees opposing closure, and in no more than 40 sec. and no less than
10 sec. with the ship in upright position. (3) the doors except for
those for emergemcy escape trunks Shall be capable of of remote release
from the central control stations and should also be capable of release
individually from a position at both sides of the door. Release
switches shall have an on-off function to prevent automatic resetting of
the system. (4) hold back hooks not subject central control station
release are prohibited, (5) a door closed remotely shall be capable of
being reopened locally from both sides of the door and after such
opening, the door shall automatically close again.(6) there should be
fire door position indicator on the indicator .
Indicator
panel in the central control room and the release mechanism shall be so
designed that the door will automatically close in the event of power
supply failure. (7) local power supply accumulators for power operated
doors shall be provided in the immediate vicinity of the doors to enable
the doors to be operated at least 10 times (open and close) after
disruption of the control system or the central power supply using local
controls. (8) the components of the local control system shall be
accessible for maintenance and adjusting.
(9) In the
event of a fire, the control system shall operate the door at the temp.
of at least 200 deg. For at least 60 min. served by the power supply and
the power supply for all other doors not subject to fire shall not be
impaired, and (10) at temperatures exceeding 200 deg. C the control
system shall automatically be isolated from the power supply and shall
be capable of keeping the door closed upto at least 945 deg.C.
'B' Class Divisions
Class differences "B" are the bulkheads, decks, blankets and coatings
Approved
non-combustible materials to prevent sufficient flame to pass through
the end of the first half hour of the standard fire test. They have an
insulation value so that the average temperature of the un-exposed side
does not exceed 140 ° C above the initial temperature or the temperature
at any point, including any junction, rises more than 225oC to the
initial temperature, the following phases:
Class "B-15" 15 minutes
Class "B-0" 0 minutes.
A
prototype or platform partition should be tested according to the
FireCode test procedure to ensure that it meets the above requirements
for integrity and temperature rise.
Class B fire protection doors
The
construction of all doors in the partition type "B" and the means in
the closed position represents the equivalent of fire as far as possible
bulkheads in which the doors of the exception that can lie vent
openings in the lower part of the doors, with a total area of the
lower opening Or equal to 0.05 m2. (1) These doors must be closed.
Retaining hooks are not permitted. The doors of class B fire must be
built with non-flammable materials approved. Class B fire protection
doors built with approved non-combustible materials in accordance with
the test method Code for fire.
Class differences, C '
Class
differences "C" are the non-flammable materials, the bulkheads, decks,
ceilings and linings, which limit requirements for the passage of smoke
and flames or temperature rise. Door Class "C" is the type of doors
installed in the class partitions "C". The approved noncombustible
materials must be constructed.
Fire dampers
Valves
are penetrating into the ventilation ducts installed bulkheads and
bridging the class "A" to maintain the division of fire resistance
capability and prevent the spread of smoke and flames in adjacent
compartments through the ventilation system.
fire integrity
Resistance
to fire is to keep the grounding element's resistance with a bulkhead
or deck intact for a period of time, 60 minutes for class "A" and 30
minutes for class "B".
Fire Detection Systems
The
PURPOSE of this regulation is to detect a fire in the space of origin
and to provide for alarm for safe escape and fire fighting activity.
For this purpose :
(1) Fixed Fire Detection and fire alarm
system installations shall be suitable for the nature of the space,fire
growth potential and potential generation of smoke and gases, (2)
manually operated call points shall be placed effectively to ensure a
readily accessible means of notification and (3) fire petrols shall
provide an effective means of detecting and locating fires and alerting
the navigation bridge and fire teams. Fire Detection Systems. – General
Requirements.
A fixed fire detection and alarms system shall be provided as per this regulation.
A
fixed fire detection and alarm system and a sample extraction smoke
detection system required as per regulations mentioned in Chapter II-2,
Part C, of SOLAS shall be of an approved type and comply with Fire
Safety Systems Code.
The function of such systems shall be tested under varying conditions of ventilation after installation.
Such
installed systems shall be periodically tested for proper functioning
under simulated fire conditions to the approval of Administration.
Detection in Machinery Spaces:
A
fixed fire detection and fire alarm system shall be installed in (i)
periodically unattended machinery spaces and (ii)m/c spaces containing
all automatic and remote control systems and equipment approved in lieu
of continuous manning of the space and also in continuously manned
spaces having a central control room.
This system shall be so
designed and installed that all the fire detectors of suitable type
will be capable of detecting the smoke or fire rapidly in any part of
the spaces under working varying condition of temperature and
ventilation.
Detection in Accommodation and Service Spaces and Control Stations:
(1)
Smoke detectors shall be fitted in all stairways, corridors, and escape
routes and if found necessary, special purpose smoke detectors shall be
fitted within ventilation ducting.
Fire Extinction Systems. – General Requirements
This system is brodadly divided in three parts:
Regulation
8 of Part C of Chapter II-2 of SOLAS. Control of Smoke spread : For
this purpose, means of controlling smoke in atriums, control m/c spaces
and concealed spaces shall be provided.
For example, in most
cargo ships of any type of all the supply air fans (usually 4) for
machinery spaces, at least one fan is reversible and can be used as an
exhaust fan in the event of fire and generation of smoke in the m/c
spaces.
In accommodation, gallies, Navigation Bridge, Steering
Flat a provision for exhaust fans is made to expel smoke from the
concerned spaces.
(2) Regulation 9 of Part C of Chapter II-2 of SOLAS.
Containment of Fire: For this purpose (i) the ship shall be subdivided by thermal and structural boundaries,
(ii) thermal insulation of boundaries shall have due regard to the fire risk of the space and adjacent spaces,
(iii)
The fire integrity of the divisions shall be maintained at openings and
penetrations by using approved materials and methods by adhering to the
relevant regulations of the SOLAS.
(3) Regulation 10 of Part C of Chapter II-2 of SOLAS.
Fire
fighting: For this purpose, following functional requirements will be
met : (A) fixed fire extinguishing systems shall be installed, having
due regard to the fire growth potential of the protected spaces, and (B)
adequate number of approved type of fire extinguishing appliances shall
be readily available.
(C) Water supply systems with approved
type and sufficient number of fire pumps, fire mains, hydrants, hoses
and nozzles complying with the regulations of the SOLAS requirements
shall be provided.
(i) Fire mains and hydrants materials readily rendered ineffective by heat shall not be used.
(ii)
Their arrangement shall be such as to avoid the possibility of
freezing, with adequate provisions for the drainage of the mains.
The
number and position of hydrants should be such that at least two jets
of water from two different hydrants may reach any part of the ship.
There will be an isolating valve and a relief valve on the fire main line as approved by the regulations.
Pressure at the hydrants: For cargo ships above 6000 grt it should be 0.27N/mm2.
(vi)
Fire pumps : For cargo ships of 1000 grt and above, there will be at
least two independently driven fire pumps, which will have the
provision for being started and stopped by local and remote switches
(normally situated on the Bridge).
Emergency fire pump : The
space containing the emergency fire pump shall not be contiguous to the
boundaries of the m/c spaces or those spaces containing main fire
pumps. There will be no direct access between the m/c space and the
emergency fire pump spaces.
The emergency fire pump shall have two
sources of electrical power supply, one from the power mains and the
other from the emergency generator bus bars.
Ventilation
arrangements to the emergency fire pump spaces shall be such as to
preclude the possibility of smoke from m/c space fire entering or being
drawn into the space.
(viii) Fire hoses shall be of non perishable
material approved by the Administration and should have a length of at
least 10 mtrs, but not more than 15 mtrs in m/c spaces and not more
than 25 mtrs for open decks on ships with breadth in excess of 30 mtrs.
(ix)
Standard nozzle sizes shall be 12mm, 16mm and 19 mm. For accom. Spaces
a nozzle size greater than 12 mm and for cargo spaces a nozzle size
greater than 19 mm need not be used. The size should be adequate to
obtain the max. discharge possible from two jets at the approved
pressure. Nozzles shall be of approved dual purpose type( i.e.
spray/jet) incorporating a shut off.
(x) Portable fire extinguishers: Their type and design shall comply with the requirements of the Fire Safety systems Code.
Ships
of 1000 grt annd above will have at least 5 portable fire extinguishers
in accom. Spaces, service spaces and control stations. CO2 fire
extinguishers shall not be placed in accom. Spaces. In control stations
and other spaces containing electrical or Or electronic equipment,
only those fire extinguishers whose extinguishing media are not
electrically conductive or harmful shall be used.
Spare charges
shall provided for 100% of the first ten extinguishers and 50% for the
remaining fire extinguishers capable of being recharged on board.
Instructions for recharging shall be carried on board.
(xi) Fixed
fire extinguishing systems: These systems for m/c spaces may be any of
the following types: Fixed gas fire extinguishing system, a fixed high
expasion foam fire extinguishing system or a fixed pressure water
spraying fire extinguishing systems, all complying with the provisions
of the Fire Safety Systems Code.
Here fire extinguishing systems using Halon 1211, 1301, and 2402 and perfluorocarbons shall be prohiibited.
(xii)
There shall be at least one portable foam applicator unit complying
with the provisions of the Fire Safety Systems Code. In addition, in
each space, approved foam type fire extinguishers each of at least 45
ltr capacity shall be provided. Additionally, there shall be provided a
sufficient number of portable foam extinguishers so located that no
point in the space more than 10 m walking distance from an extinguisher
and that there are at least two such extinguishers in each space.
(xiii)
Paint Lockers shall be protected by (i) Co2 system designed to give a
minimum volume of free gas equal to 40% of the gross volume of the paint
locker, (ii) a dry powder system giving at least 0.5 kg powder/m3 of
the space, (iii) a water spraying or sprinkler system connected to
ship’s fire mains designed for 5 ltr/m2 /min. All above systems shall
be operable from outside the protected space.
(ivx) Fire
Extinguishing systems for cargo spaces: Fixed Co2 or inert gas system
complying with the provisions of the Fire Safety System Code. For cargo
tank protection on Tankers a fixed deck foam fire extinguishing systems
complying with provisions of the Fire Safety System Code shall be used.
(xv)
Approved Fire Fighter’s Outfits (atleast two in nos.) shall be carried
by all ships. Additionally, on tankers two extra sets will be carried.
# The article was written by two author and then merged before publishing. Various books are used as reference before writing this article but no part is being reproduced but stated in a different easy way.
# Cover image credit: Pintrest (If you have any problem regarding the post contact us!)
Author Arpit Singh & Amit
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