#7 LIFERAFTS: SOLAS REQUIREMENTS, SAFETY FEATURES & LAUNCHING PROCEDURE
Life rafts are survival equipment provided as a life-saving appliance on every seagoing merchant or passenger ship, in addition to the lifeboats.
Life rafts are much easier to
launch than lifeboats. In emergencies, evacuation from the ship can be done
without manually launching any of them, as the life rafts are designed with an
auto-inflatable system.
Where Are Liferafts Located On Ships?
Life rafts are stored in a
fibreglass container, with a high-pressure gas used to inflate life rafts
during an emergency.
A Hydrostatic Release Unit
(HRU) is connected to the raft container and ship, which releases the raft even
after the vessel sinks in water.
The
particulars of the raft are stencilled on the container, which includes the
capacity, manufacturing date, servicing date, company name etc., along with
the launching procedure with a
photogenic display for easy understanding.
The essential survival items are already stored in the raft, including rations, pyrotechnics, life jackets etc.
Some ships carry a davit launching system that allows the crew to inflate and board the raft on the deck, avoiding the risk of entering the seawater.
Important Solas Requirements For Life Rafts
All liferaft provided
on ships should be bestowed with its painter permanently attached to the
vessel.
Each liferaft or group
of liferafts should be stowed with a float-free arrangement complying with the
requirements so that each floats free. If it is an inflatable raft, it should
inflate automatically when the ship sinks.
Liferafts should be
stowed to permit the manual release of one raft or container at a time from the
securing arrangements.
Davit-launched
liferafts should be stowed within reach of the lifting hooks unless some
transfer is provided, which is not rendered inoperable within the limits of
trim and list as required or by ship motion or power failure.
Liferafts intended for
throw-overboard launching should be stowed to be readily transferable for
launching on either side of the ship.
Servicing of Liferafts
All liferafts shall be
serviced:
- at
intervals not exceeding 12 months (if impracticable, the administration
may extend this period to 17 months)
- at
proper service stations with proper servicing facilities and trained
professionals
Davit-launched liferaft
automatic release hooks should be maintained following instructions for onboard
maintenance
Essential Requirements for Liferafts and
Carrying Capacity
The liferaft of any ship needs
to follow the regulations mentioned in SOLAS. Some of the important points
regarding liferafts are:
- The
lift raft should be capable of withstanding exposure for 30 days afloat in
all sea conditions
- When
dropped into the water from a height of 18 metres, the life raft and all
equipment in it will operate satisfactorily.
- The
floating life raft should be capable of withstanding repeated jumps on it
from a height of at least 4.5 metres above its floor, both with and
without the canopy erected
- It
can be towed at 3 knots with its complete equipment, complement of persons
and one anchor streaming.
- Canopy
to provide insulation and protection against heat and cold by two layers
of material separated by an air gap
- Interior
to be of a non-discomforting colour
- It
shall admit sufficient air for the occupants at all times, even when the
entrance is closed
- It
shall be provided with at least one viewing port
- It
will be given with a means of collecting rainwater
- It
shall be provided with a tool to mount a survival craft radar transponder
(SART) at the height of at least 1 meter above the sea level
- It
shall have sufficient headroom for the sitting occupants under all parts
of the canopy
- The
minimum carrying capacity must be at least six persons
- The
maximum weight of its container, as well as the equipment, should not
exceed 185 kilos
- The
life raft shall be fitted with an efficient painter of length equal to the
minimum of 10 metres plus the distance from the stowed position to the
waterline in the lightest seagoing condition or 15 metres, whichever is
greater
- A
manually controlled lamp shall be fitted on the top of the canopy, and the
light shall be white, and it must operate for at least 12 hours with a
luminous intensity of not less than 4.3 candela
- If
the flashlight is fitted, it shall flash at a rate of not less than 50
flashes and not more than 70 flashes per minute for the 12 hours that it
burns
- A
manually controlled lamp shall be fitted inside the life raft, capable of
continuous operation for at least 12 hours
- When
the liferaft is loaded with a full complement of persons and equipment, it
should be capable of withstanding a lateral impact against the ship side
at an impact velocity of not less than 3.5m/s and also drop into the water
from a height of not less than 3 metres without damage
- CO2
does inflation with a small quantity of N2, which acts as an anti-freezing
element. Also, CO2 is non-flammable and weighs more than air, adding
buoyancy to the raft. The freezing point of CO2 is -78 degrees so that it
can inflate life rafts at shallow temperatures
- Location
on a ship:
– Forward
– At embarkation stations on both port and starboard sides - The
painter breaking strength should be:
– 15kN for 25 people and more
– 10 kN for 9 to 24 people
– 7.5 kN Rest (6-9)
Safety Features on a Life raft
Some of the main safety
features on a life raft are:
- Pressure
relief valve
- Stabilizing
pocket
- Insulated
canopy with two layers for protection against heat and cold
Important life raft Equipment
All life rafts on ships are
fitted with the following equipment:
- Rescue
quoits with minimum 30-metre lines
- Non-folding
knives with buoyant handles
- For
12 persons or less, one bailer. For more than 13 persons, 2 bailers should
be kept.
- Two
sponges
- Two
buoyant paddles
- Three
tin openers
- Two
sea anchors
- One
pair of scissors
- One
first aid waterproof kit
- One
whistle
- One
waterproof torch for communicating morse code with one spare set of
batteries and bulb
- One
signalling mirror/heliograph
- One
radar reflector
- One
life-saving signal waterproof card
- One
fishing tackle
- Food
ration totalling not less than 10000 kJ for each person
- Water
ration- 1.5 litres of fresh water for each person
- One
rustproof graduated drinking vessel
- Anti-seasickness
medicine is sufficient for at least 48 hours, and one seasickness bag for
each person.
- Instructions
on how to survive (Survival booklet)
- Instructions
on immediate action
- TPA
is sufficient for 10% of the number of persons or two, whichever is
greater
- Marking
shall be SOLAS ‘A’ Pack
- 6
Hand Flares
- 4
Rocket Parachute Flares
- 2
Buoyant Smoke Signals
Markings on a Liferaft Container
Important markings provided on
a liferaft container are:
- Maker’s
name and trademark
- Serial
number
- Name
of Authority
- Number
of persons carried
- SOLAS
emergency pack enclosed
- Date
of the last service
- Length
of painter
- Maximum
height of stowage
- Launching
instructions
Markings on an inflatable Liferaft
Important markings provided on
an inflatable type of liferaft are:
- Maker’s
name and trademark
- Serial
Number
- Date
of manufacture
- Name
of approving authority
- Name
and place of the last service
- Number
of persons permitted
Launching of a liferaft when the ship sinks
and HRU activates (Auto)
A general overview of the
launching procedure of a liferaft when the ship sinks are:
- When
the ship sinks up to 4 metres, the water pressure will activate a sharp
knife in the HRU
- It
will cut the securing rope around the container/canister of the raft, and
the raft will float free
- As
the ship sinks further, the painter line will stretch, and it will inflate
the life raft
- Due
to the increase in buoyant pressure, the weak link will break at around
2.2 kN +/- 0.4, and the raft will be on the surface.
Launching the life raft manually
- Take
out the painter of the raft
- Fasten
it to the ship side at a strong point
- Remove
the railing and check overboard for any obstructions
- Unfasten
the hook from the cradle
- Two
people can lift the life raft and throw it overboard
- After
its thrown, pull the painter sharp until the life raft inflates
- With
the painter, pull it towards the ship’s side
- Lower
the embarkation ladder or jump directly onto the life raft, depending on
the situation and the time at hand
- Sit
wide order face to face to prevent any imbalance
- Ensure SART and EPIRB have been
carried
- Take
a headcount
- Cut
the painter using the knife, paddle, or anchor, clear away from the ship.
If the life raft inflates and
is upside down, the raft has a righting strap capable of stabilizing it. Climb
onto the CO2 cylinder and pull it in the same direction as the wind to do so.
Launching the life raft by the davit
- Remove
the ship’s handrail
- Remove
lashings from the container
- Lower
the davit and lock it with the lifting shackle
- Secure
canister lines outboard
- Secure
browsing line
- Pull
the painter out approximately 5-6 metres
- Secure
the painter’s line
- Pull
the entire length of the painter
- Now
lift the life raft canister to some height
- Pull
the painter sharply and let it inflate
- After
it inflates, secure the liferaft
- One
person should go in and make some checks
- Collect
the SART and EPIRB
- Go
inside and sit evenly
- Release
the bowsing line and pass to the raft
- Check
if the launching area is clear
- Lower
the raft using the brake release
- Operate
hook release 1m above the water or allow the raft to ride a crest of the
wave to put the load on the water, and it will automatically release
- Cut
the painter and clear away
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