D1 mc s & m topic 3 loadline

D1MC Semester 1 / Survey & Maintenance / January 2009 /Topic 3 – LOADLINE 1
To Be A World Class Maritime Academy
International Convention on
Load Line Rules 1966
D1MC

International Convention on Load
Lines 1966
The first International Convention on Load Lines, adopted in
1930, was based on the principle of reserve buoyancy,
although it was recognized then that the freeboard should also
ensure adequate stability and avoid excessive stress on the
ship's hull as a result of overloading.
In the 1966 Load Lines convention, adopted by IMO,
provisions are made determining the freeboard of ships by
subdivision and damage stability calculations.

• The Convention establishes limitations on the draught to
which a ship on international voyages may be loaded, in the
form of freeboards, which should ensure adequate stability and
avoid excessive stress and the ship's hull as a result of
overloading. It also deals with external weather tight and
watertight integrity, and provisions are made for determining
the freeboard of tankers by sub division and damage stability
calculations.
• The regulations take into account the potential hazards present
in the different zones and at different seasons. The technical
annex contains several additional safety measures concerning
doors, freeing ports, hatchways and other items. The main
purpose of these measures is to ensure the watertight integrity
of ship's hulls below the freeboard deck.

Application
• Convention shall apply to ships engaged on
international voyages, except:
* warships;
* new ships of less than 24 metres in length;
* existing ships of less than 150 tons gross;
* pleasure yachts not engaged in trade, and;
* fishing vessels.

• CONDITIONS OF ASSIGNMENT OF
FREEBOARD

Assignment of Freeboard
• Procedure for Assignment of Freeboard
• The Merchant Shipping (Load Lines) rules came into operation on
21 July 1968 and contact the requirements for the surveying and
assignment of freeboards to ships and the issue of Load Lines
Certificates. The assigning authorities are the Government (Ministry
of Transport, Malaysia) or Classification Societies such as Lloyd's
Register of Shipping (LR), ABS etc.
• Application for the assignment of freeboards to a ship and for the
issue of a Load Lines Certificate is made to an Assigning Authority
by or on behalf of the owners. The application must be accompanied
by plans, drawings and specifications that relate to the design and
construction of the ship.

The ship is then surveyed and the surveyor must ascertain that:
1. the construction of the ship shall be such that her structural
strength will be sufficient for the free boards to be assigned
2. the stability in all probable loading conditions will be
sufficient for the freeboards to be assigned; and
3. the construction of fittings and appliances for the protection of
openings (sills, hatch coamings, closing appliances, side
scuttles, freeing ports, scuppers, inlets and discharges),
Arrangements for the protection of the crew such as guard
rails (means of access), all comply with the specifications laid
out in the rules.

The surveyor provides the Assigning Authority with it report,
which gives the results of the survey, and if that proves
satisfactory freeboards are assigned to the ship. The owner is
then given particulars of the freeboards assigned and the
positions in which Load Lines, the Deck line and the load line
mark to be actually marked. The owner is also given two
copies of the surveyor's report and is issued with a 'Load Line
Certificate’.

Load line Certificate
• A Load Lines Certificates is valid for not more than 5 years after the
date of completion of the survey, subject to annual endorsements
(Annual survey) within 3 months either way of each anniversary
date of the certificate. This to ensure that alterations have not been
made to the hull or superstructures which would affect the
calculation determining the position of the Load Line and so as to
ensure the maintenance in an effective condition of fittings and
appliances for:
1. Protection of openings.
2. Guard rails
3. Freeing port, and
4. Means of access to crews’ quarters.

Load line Certificate
The authority may cancel a certificate if:
1. The ship does not comply with the conditions of assignment.
2. The structural strength of the ship is lowered to an unsafe
standard (that makes the ship unsafe)
3. The information on which the freeboards were assigned was
incorrect
4. A new certificate is issued
5. The ship ceases to be registered in the country (Malaysia)
6. The ship is not periodically inspected (the survey not done or
defects not corrected).

Surveys and inspections
• (a) An initial survey before the ship is put in service,
which shall include a complete inspection of its structure
and equipment in so far as the ship is covered by the
present Convention. The survey shall be such as to ensure
that the arrangements, materials and scantlings fully
comply with the requirements of the present Convention.
• (b) A renewal survey at intervals specified by the
Administration but not exceeding five years, which shall
be such as to ensure that the structure, equipment,
arrangements, materials and scantlings fully comply with
the requirements of the present Convention.

• (c) An annual survey within 3 months before or after each
anniversary date of the certificate to ensure that:
(i) alterations have not been made to the hull or superstructures
which would affect the calculations determining the position
of the load line;
(ii) the fittings and appliances for the protection of openings,
guard rails, freeing ports and means of access to crew's
quarters are maintained in an effective condition;
(iii) the freeboard marks are correctly and permanently indicated;
(iv) the information required to be supplied to Master is provided.
Surveys and inspections

Definitions
1) Length. The length (L) shall be taken as 96% of the total
length on a waterline at 85% of the least moulded depth
measured from the top of the keel, or as the length from the
foreside of the stem to the axis of the rudder stock on that
waterline, if that be greater.
2) Perpendiculars. The forward and after perpendiculars shall
be taken at the forward and after ends of the length (L). The
forward perpendicular shall coincide with the foreside of the
stem on the waterline on which the length is measured.
3) Amidships. Amidships is at the middle of the length (L).

4) Breadth. Unless expressly provided otherwise, the breadth (B)
is the maximum breadth of the ship, measured amidships to
the moulded line of the frame in a ship with a metal shell and
to the outer surface of the hull in a ship with a shell of any
other material.
5) Moulded depth. This is the vertical distance measured from the
top of the keel to the top of the freeboard deck beam at side.

9) Freeboard deck. The freeboard deck is normally the
uppermost complete deck exposed to weather and sea,
which has permanent means of closing all openings in the
weather part thereof, and below which all the openings in
the sides of the ship are fitted with permanent means of
watertight closing. In a ship having a discontinuous
freeboard deck, the lowest line of the exposed deck and the
continuation of that line parallel to the upper part of the
deck is taken as the freeboard deck.
A lower deck may be designated as the freeboard deck,
provided it is a complete and permanent deck continuous
in a fore and aft direction at least between the machinery
space and peak bulkheads and continuous athwartships.
Definitions

When a lower deck is designated as the freeboard deck, that
part of the hull which extends above the freeboard deck is
treated as a superstructure so far as concerns the application of
the conditions of assignment and the calculation of freeboard.
It is from this deck that the freeboard is calculated.

Deck Line (Regulation 4)
• The deck line is a horizontal line 300 mm in length and 25
mm in breadth. It shall be marked amidships on each side
of the ship, and its upper edge shall normally pass through
the point where the continuation outwards of the upper
surface of the freeboard deck intersects the outer surface of
the shell plating

However, the deck line may be placed with reference to
another fixed point on the ship on condition that the freeboard
is correspondingly corrected and that the reference point
location and the identification of the freeboard deck is
clearly indicated on the International Load Line Certificate.
This is typical in the case of a ship having a radiused
sheerstrake (rounded gunwale)

Regulation 5
Load Line Mark
The Load Line Mark shall consist of a ring 300 mm
in outside diameter and 25 mm wide which is
intersected by a horizontal line 450 mm in length and
25 mm in breadth, the upper edge of which passes
through the centre of the ring. The centre of the ring
shall be placed amidships and at a distance equal to
the assigned summer freeboard measured vertically
below the upper edge of the deck line.

Load Line Mark
300 mm
450 mm
25 mm

If timber freeboards are assigned, the timber load lines are
marked in addition to the ordinary load lines as shown in figure:

Minimum free boards are assigned so that a vessel remain
seaworthy when loaded and to provide reserve buoyancy so
that:
1. The vessel will not be in danger of foundering in heavy seas
2. In the event of major damage the vessel will still remain afloat
or will sink slowly enough so as to enable the crew to get clear
International convention has divided the world into zones the
least dangerous 'Tropical' zone and the most dangerous
'winter, North Atlantic'. The winter in the North Atlantic is
notoriously rugged and so that is where the ship needs the
greatest amount of intact space above the waterline.

Load line Zones
• The seasonal zones, areas and periods that determine the
appropriate load line in a particular sea area at a given time of
year are by way of the chart.
• The Tropical, Summer and Winter freeboard zones are based
upon the following weather criteria:
• Summer Zones – Regions where not more than 10% of wind
speeds exceed force 8 Beaufort (34 knots).
• Tropical Zones – Regions where not more than 1% of wind
speeds exceed force 8 Beaufort (34 knots) and not more than
one tropical storm in a ten-year period occurs in an area of 5º
latitude/longitude square in any one separate calendar month.
• Winter Zones – Are all other regions.

• Tropical Zone: - The permanent tropical is colored 'green' on
the zone chart, the boundary north and south of it may be seen
on the zone chart. The ships are allowed to load up to tropical
Load line when they are in this zone through out the year.
• Seasonal Tropical or Summer Zones or Areas: - these zone
or areas are found on the zone chart with 'Light Green colors',
which lies between the permanent tropical, and summer zones.
The ships loading in these areas are required to load according
to the" season. Seasonal period for this is as:

Seasonal Tropical or Summer Zones
• North Atlantic Tropical : 1st
November - l5th July
• North Atlantic Summer : 16th.July- 3rd
October
• Arabian Sea Tropical : 1st
September – 3rd
May
• Arabian Sea Summer : 01st
June - 3Ist August
• Bay of Bengal Tropical: 01st
December - 30th.April
• Bay of Bengal Summer: 01st
May - 30th
November
• China. Sea Tropical : 21st
Jan – 30th
April
• China Sea Summer : 01st
May – 20th
January
• South Indian Ocean North Pacific & South Pacific Tropical: 01st
April – 30th
November
• South Indian Ocean North Pacific & South Pacific Summer. 01st
December
– 31st
March

• It is a criminal offence for the Master and/or shipowner to allow a
vessel to be operated in a zone, when in the upright condition, the
relevant amidships zone load line would be below the still load
waterline. Such an action would immediately invalidate all
Classification Society and Load Line certification and will lead to
criminal prosecution.

Regulation 10
Information to be supplied to the master
(1) The master of every new ship shall be supplied with sufficient
information, in an approved form, to enable him to arrange for the
loading and ballasting of his ship in such a way as to avoid the
creation of any unacceptable stresses in the ship's structure,
provided that this requirement need not apply to any particular
length, design or class of ship where the Administration considers
it to be unnecessary.
(2) The master of every new ship which is not already provided with
stability information under an international convention for the
safety of life at sea in force shall be supplied with sufficient
information in an approved form to give him guidance as to the
stability of the ship under varying conditions of service, and a
copy shall be furnished to the Administration.

Loadline Survey

Preparation for loadline survey
1) Check that all access openings at ends of enclosed structures
are in good conditions. All dogs, clamps and hinges to be
free and well greased. All gaskets and water-tight seals
should be crack free. Ensure that the doors open from both
sides
2) Check all cargo hatches and access to holds for weather
tightness
3) Check the efficiency and securing of portable beams
4) If portable wooden hatch covers are used check that they are
in good condition
5) If tarpaulins are used at least two should be provided for
each hatch and in good condition

6) Inspect all machinery space opening on exposed
deck
7) Check that any manholes and flush scuttles are
capable of being made watertight
8) Check that all ventilator openings are provided with
efficient weather tight closing appliance
9) All air pipe should be provided with satisfactory
means for closing and opening
10) Inspect any cargo ports below the freeboard deck
and ensure that all of them are watertight

11) Ensure that non return valves on overboard valves
are operating in a satisfactory manner
12) Side scuttles and openings below the freeboard
deck must have efficient internal watertight
deadlights
13) Check that all freeing ports are in satisfactory
conditions
14) All guard-rails and bulwarks should be satisfactory
condition
15) De rust and paint the deck line, loadline marks, load
line and the draught marks

Quick Info
Deadlight - steel, hinged cover to protect the porthole's glass in
heavy weather or to prevent lights inside the ship from
showing outside; it can be mechanically secured by screws
and nuts
Scuttles - small opening in a ship's deck, side or compartment
which can be closed by a shutter when required
Freeing ports - openings cut in the bulwark to free the deck of
water
Bulwark - shell plating about one metre in height built around the
outboard edge of upper deck from forecastle to poop to protect
men and cargo against rough seas
Gunwale - the upper edge of the side of a small ship or boat, or
upper edge of bulwarks in bigger ship

THANK YOU

D1 mc s & m topic 3 loadline

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