1. INTERNATIONAL CONVENTION ON LOAD
LINES 1968
SHIP CONSTRUCTIONS
D1MC 34 / GROUP 2
Lecturer : Capt. Siva Vivekanandan
Prepared By: 1. Muhammad Fauzee Bin Abd Rahman / D1MC 461
2. Md Mizanur Rahman Parvez / D1MC 468

2. • The first international agreement for universal
application of load line regulations and applied
to seagoing ships in international trade and
• 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.
Introduction and history
1930 Load Line Convention

3. • The 1930 load Line Convention was an important
step in establishing universally applicable rules.
• the decades following the adoption of the 1930
Convention saw developments in ship design and
methods of construction which began to make the
Convention rules look outdated: ships, tankers,
grew in size; specialized ship designs to meet
different trades; machinery spaces in dry cargo
ships being located away from the traditional
midships; metal hatchway covers were replacing
wooden ones; and welding was replacing riveting.
Introduction and history
1930 Load Line Convention

4. • was held at IMO headquarters in London from 3
March to 5 April 1966 and was attended by
delegations from 52 States and observers from 8
States was adopted on 5 April 1966 and entered
into force on 21 July 1968.
• The terms of the convention stated it would
enter into force 12 months after at least 15
countries, 7 of which possessed not less than one
million gross tons of shipping had accepted it.
These conditions were met in a short time - one
reason being that the Convention provided for a
general reduction in freeboard allowance for
most ships compared to the 1930 Convention.
Introduction and history
1968 Load Line Convention

5. • The 1966 conference agreed that the revision
of the 1930 Load Line convention required re-
examination of a number of issues, including:
• prevention of the entry of water into the hull;
• adequate reserve buoyancy; protection of the
crew;
• adequate structural strength of the hull;
•and limitation of water on the deck.
Introduction and history
1968 Load Line Convention

6.  The minimum freeboard was designed to
provide a standard of "reserve buoyancy",
while the protection of openings in the hull
and superstructures, such as hatches,
ventilators, air pipes, scuppers, overhead
discharges and the access openings in the
end bulkhead of superstructures were an
important consideration in the assignment of
freeboard.
Another major concern was protection to the
crew by consideration of the strength of
gangways, guard rails, lifelines etc.

7. Load Lines Convention sets out rules for
calculation and assignment of freeboard and
takes into account the potential hazards
present in different zones and different
seasons.
The technical annex contains several additional
safety measures concerning doors, freeing
ports, hatchways and other items.
Introduction and history
1968 Load Line Convention

8. The main purpose of these measures is to
ensure the watertight integrity of ships' hulls
below the freeboard deck.
All assigned load lines must be marked
amidships on each side of the ship, together
with the deck line.
Ships intended for the carriage of timber deck
cargo are assigned a smaller freeboard as the
deck cargo provides protection against the
impact of waves.
Introduction and history
1968 Load Line Convention

9. 1966 Load Line Convention
The 1966 Convention is made up of:
• Articles - cover matters of contract between
governments, survey and certification.
• Annex I - Regulations for determining load
lines, is divided into four chapters.
• Chapter I - General -for example, strength of
hull, types of ships, definitions, markings.
• Chapter II - Conditions of assignment of
freeboard;

10. 1966 Load Line Convention
The 1966 Convention is made up of:
• Chapter III - Freeboards - evaluation of
freeboard in terms of geometrical and
physical characteristics of any ship.
• Chapter IV - Special requirements for ships
assigned timer freeboards.
• Annex II defines zones, areas and seasonal
periods appropriate to the various load line
markings.
• Annex III prescribes the form and scope of
certificates, including the International Load
Line Certificate and the International Load
Line Exemption Certificate

11. Considerations for calculating a ship's freeboard
Freeboard
The distance between the top of the hull and the
waterline. As the ship is loaded, it sinks deeper into
the water so the freeboard is reduced. The
positioning of the load line mark is aimed at
ensuring the freeboard is the minimum necessary
for the safety of the ship.
Keel
Statutory
Freeboard
Statutory
Draught
Moulded
Depth
Extreme
Freeboard
Extreme
Depth
Extreme
Draught

12. Structural Strength
The deeper the draft of a ship (the
amount of the ship that is underwater),
the greater are the loads imposed on the
ship's structure. So a ship with a deeper
draught requires a higher freeboard.

13. Deck Height
Platform height (the height of the weather
deck above the waterline) is a measure of
how the vessel may be affected by seas
which sweep across the deck.

14. Transverse Stability
While freeboard does not directly determine
the side to side stability of a ship, higher
freeboard will allow a ship to roll further before
submerging the deck.

15. Hull Form
Sheer describes the curve between bow and stern. A
ship with high freeboard at the bows and stern
compared to midships (where freeboard is
measured) has more reserve buoyancy.

16. Fullness
The underwater shape of a hull. A rectangular
cross section as on a tanker, is described as
"full" and has less reserve buoyancy with the
same freeboard than a more rounded hull like
that of tugboat or liner.

17. Length
A long ship, with only a few feet of
freeboard, has less reserve buoyancy than a
shorter ship with the same freeboard.

18. Type of Vessel and Cargo
Tankers and timber carrying ships with
buoyant cargoes require less freeboard than a
passenger liner or containership.

19. Season and Zone
Weather conditions normally encountered along a
ship's trade route effects its seaworthiness. Ships
sailing the North Atlantic in Winter are exposed to
much more severe conditions than one sailing
around the South Seas.

20. LTF - Lumber, Tropical Fresh - This is the draft to
which the vessel can load when carrying lumber in
the Tropical Fresh designated zone.
LF - Lumber, Fresh - This is the draft to which the
vessel can load when carrying lumber in the Fresh
designated zone.
LT - Lumber, Tropical - This is the draft to which
the vessel can load when carrying lumber in the
Tropical designated zone.
LS - Lumber, Summer - This is the draft to which
the vessel can load when carrying lumber in the
Summer designated zone.

21. LW - Lumber, Winter - This is the draft to which
the vessel can load when carrying lumber in the
Winter designated zone.
LWNA - Lumber, Winter, North Atlantic - This is
the draft to which the vessel can load when
carrying lumber in the Winter North Atlantic
designated zone.
F - Fresh - This is the draft to which the vessel
can load when not carrying lumber in the Fresh
designated zone.
TF - Tropical, Fresh - This is the draft to which
the vessel can load when not carrying lumber in
the Tropical Fresh designated zone

22. F - Fresh - This is the draft to which the vessel can
load when not carrying lumber in the Fresh
designated zone
T - Tropical - This is the draft to which the vessel
can load when not carrying lumber in the Tropical
designated zone
S - Summer - This is the draft to which the vessel
can load when not carrying lumber in the Summer
designated zone
W - Winter- This is the draft to which the vessel
can load when not carrying lumber in the Winter
designated zone

23. WNA - Winter, North Atlantic - This is the draft to
which the vessel can load when not carrying
lumber in the Winter North Atlantic designated
zone
LR - Lloyds Register - The initals of the
Classification Society which assigns the marks.
Other possible Initials are: BV - Bureau Veritas,
GL - Germanischer Lloyd, AB - American Bureau
of Shipping, and so on.

24. Amendments 1971, 1975, 1979, 1983
The 1966 Convention provided for amendments
to be made by positive acceptance.
Amendments could be considered by the
Maritime Safety Committee, the IMO Assembly
or by a Conference of Governments.
Amendments would then only come into force
12 months after being accepted by two-thirds
of Contracting Parties. In practice, amendments
adopted between 1971 and 1983 never
received enough acceptances to enter into
force. These included:
· the 1971 amendments - to make certain
improvements to the text and to the chart of
zones and seasonal areas;

25. · THE 1975 AMENDMENTS - TO INTRODUCE THE
PRINCIPLE OF 'TACIT ACCEPTANCE' INTO THE
CONVENTION;
· THE 1979 AMENDMENTS - TO MAKE SOME
ALTERATIONS TO ZONE BOUNDARIES OFF THE COAST OF
AUSTRALIA; AND
· THE 1983 AMENDMENTS - TO EXTEND THE SUMMER
AND TROPICAL ZONES SOUTHWARD OFF THE COAST OF
CHILE.

26. The 1995 amendments
Adopted: 23 November 1995
Entry into force: 12 months after being
accepted by two-thirds of Contracting
Governments.
Status: superseded by 2003 amendments
The 2003 amendments
Adopted: June 2003
Entry into force: 1 January 2005

27. The amendments to Annex B to the 1988 Load
Lines Protocol include a number of important
revisions, in particular to regulations
concerning: strength and intact stability of
ships; definitions; superstructure and
bulkheads; doors; position of hatchways,
doorways and ventilators; hatchway coamings;
hatch covers; machinery space openings;
miscellaneous openings in freeboard and
superstructure decks; cargo ports and other
similar openings; spurling pipes and cable
lockers; side scuttles; windows and skylights;
calculation of freeing ports; protection of the
crew and means of safe passage for crew;
calculation of freeboard; sheer; minimum bow
height and reserve buoyancy; and others.

28. Regulation 27
Types of ships
(1) For the purposes of freeboard computation
ships shall be divided into Type "A" and Type "B".
Type "A" ships
(2) A Type "A" ship is one which is designed to
carry only liquid cargoes in bulk, and in which
cargo tanks have only small access openings
closed by watertight gasketed covers of steel or
equivalent material. Such a ship necessarily has
the following inherent features:
(a) high integrity of the exposed deck; and (b)
high degree of safety against flooding, resulting
from the low permeability of loaded cargo spaces
and the degree of subdivision usually provided.

29. (3) A Type "A" ship, if over 150 metres (492
feet) in length, and designed to have empty
compartments when loaded to its summer load
waterline, shall be able to withstand the
flooding of any one of these empty
compartments at an assumed permeability of
0.95, and remain afloat in a condition of
equilibrium considered to be satisfactory by
the Administration. In such a ship, if over 225
metres (738 feet) in length, the machinery
space shall be treated as a floodable
compartment but with a permeability of 0.85.

30. Type "B" ships
(5) All ships which do not come within the
provisions regarding Type "A" ships in
paragraphs (2) and (3) of this Regulation
shall be considered as Type "B" ships.