Cargo Work

Draft, Trim and Stability

The Load Line Marks

LR the symbols of the classification society (Lloyds Register) by the side of the Plimsoll

mark

TF Tropical Fresh (water) F Fresh Water T Tropical (Sea Water)

S Summer (Sea Water) W Winter (Sea Water)

WNA Winter North Atlantic (Sea Water)

Criteria of Stability:

Extract from the Load Line Rule (1968)

The area under the curve of Righting Levers shall not be less than:

0.055 metre-radians up to an angle of heel of 30

0.09 metre-radians up to an angle of heel of 40

0.03 metre-radians between the angles of heel of 30 and 40

The Righting Lever shall be at least 0.20 metre at an angle of heel equal to or greater than 30

The maximum Righting Lever shall occur at an angle of heel not less than 30

The Initial Transverse Metacentric Height (GM) shall not be less than 0.15 metre

Ship Stability working with kg, TM, Draft, Displacement and Trim including LCB

and LCF

Method of working:

The following example shows how a ships stability booklet has pre-determined conditions of

loading and the consequent stability criteria.

The said condition is 12; each Departure condition has an Arrival condition.

In the Departure condition the vessel is assumed to be sailing out with a load of cargo and

with full bunkers and stores. The ballast is negligible.

In the Arrival condition the vessel is assumed to have arrived her disport/ way port (may be

bunkering for long voyage), here the cargo remains the same only change is in the bunkers

and FW.

The Arrival condition is to be worked out prior departure since the arrival condition

determines the loading of the cargo. Since no vessel would like to arrive a port in a critical

condition not satisfying the stability criteria.

The weight is multiplied with the kg of each compartment to obtain the vertical moments.

These are added up (all cargo, ballast, Bunkers and light ship) and the total of the V-M is

divided by the displacement to get the final KG

In the same way the weight is multiplied with the lcg of each compartment to obtain the

longitudinal moments. These are added up (all cargo, ballast, Bunkers and light ship) and

the total of the L-M is divided by the displacement to get the final LCG.

Noting the Displacement the tables are referred to obtain the LCB, Mean Draft and the

Trimming Moment. With these inputs the final drafts and the GM is calculated.

For obtaining the Fluid GM, the FSM of the compartments are read off from the tank data

sheets.

The total of the FSM when divided by the displacement gives the FSC that is to be subtracted

from the GM to obtain the GM (F).

The following shows the departure condition of a ship, the general particulars are given.

And the following gives the arrival condition for the same ship the cargo is the same, only

change being the fuel and the ballast.

The following are extract from the hydrostatic table of ship A.

Given that the morning draft in sea water of ship A is Forward: 8.92m and Aft: 9.12m

Ship A loads cargo throughout the morning shift and her sailing drafts are:

Fwd: 8.99m, Aft: 9.19m

To find the amount of cargo loaded. Note, during the morning the ship received H.O. bunkers

100MT and consumed 10MT of FW.

Morning Mean Draft: (8.92 + 9.12)/ 2 = 9.02m

Sailing Mean Draft: (8.99 + 9.19)/ 2 = 9.09m

Displacement at 9.02m: 20419

Displacement at 9.09m: 20604

Thus the difference in displacement would be: (20604 20419) = 185 MT

Bunkers received: 100MT

FW consumed: 10MT

Thus the cargo loaded would be: 185 100 = 85 MT (correcting for the bunker) and

85 + 10 = 95MT (correcting for the FW consumed)

For change of trim the earlier example is to be referred.

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Securing Cargo

Need for solid stow and securing of all cargoes

Cargo onboard a ship will tend to shift with the motion of the ship. This necessitates the cargo

to be lashed (secured) to the ship structure. However the lashing with ropes/ wire ropes/ iron

restraining bars is not very effective because of the fact that the tightened lashings have a

tendency to work loose with the motion of the ship.

On shore any nut which is fitted tightly on a bolt works loose with vibrations as such - spring

washers are used together with check nuts and split pins to prevent the working loose of

such nuts. This is not practical on shipboard lashings - except for turnbuckles and bottle

screws with restraint bars. Below deck lashings further are not attended to during sailing and

if they work loose it is practically impossible to do a very effective job to re-secure them.

Temporary measures are often adopted and these may not be very effective as stated

earlier.

Thus the only way to prevent the lashings from working loose is to stow the cargo very close

to each other and then to shore the cargo with timber. This would prevent the cargo from

acquiring momentum while swaying with the ship and thus prevent to a large extent the

working loose of the lashings.

For bagged cargo if the same is not stowed solidly and thus allowing too much of broken

stowage, would tend to shift with the motion of the ship, thus shifting the centre of gravity

laterally and inducing a list to the ship. This coupled with the heeling of the ship would make

the weather deck of a ship too close to the water line and thus endanger the safety of the

ship.

Bulk cargo on general cargo carriers are therefore saucered with the same cargo, in order to

prevent the cargo from shifting to one side.

Deck cargo due to the high KG is especially vulnerable lateral shifting and the lashings work

loose and also to part lashing. Especially since the transverse momentum gained by such

cargo during the rolling of a ship is liable to part lashings. Thus all deck cargo has to be

definitely shored and then also lashed to deny the cargo from gaining any momentum.

Deck cargo - Lashed

Deck Cargo - Shored and Lashed

Cargo liable to slide during rolling, such as steel rails, should be Stowed fore and aft

All long cargoes such as steel rails, pipes, long steel plates as well as steel coils are stowed

with their ends in the fore and aft direction. This again is necessary due to the fact that most

of theses cargo cannot be individually lashed they rather grouped into bundles and the

bundles are lashed to make many small bundles of pipes or rails as the case may be. This

prevents the individual pipes from sliding and since as mentioned the transverse momentum

is quite large when the ship is rolling, and the pipes are thus prevented from damaging the

sidewalls of the hold. This is severe since repeated banging has resulted in tearing holes in

the shipside plates below the waterline and the ship capsizing due the inflow of water.

If the pipes / rails are stowed in the fore and aft direction this is prevented.

Bundling of long cargo (pipes/ rails):

This is the first tier. It is important to place the dunnage to spread the load as well as to

facilitate the passing of slings at the disport. The lashing wires are also placed prior to loading

the cargo. The size of the bundles should be to the capacity of the derrick/ crane that would be

used to discharge the cargo. The number of lashing wires is dependent on the weight of the

bundles as well as the length of the cargo.

As each bundle is completed the lashings are closed and tightened. And subsequently

dunnage is again placed and the lashing wires again spread on top of the earlier cargo.

Stowage and securing for vehicles and trailers

Vehicle lashing on deck

Force parallel to and across the deck = 1.0 W

Force normal to the deck = 1.4 W

Force in the longitudinal direction = 0.3 W

The above forces are intended to represent the total force to be applied in each direction

i.e., the aggregate of the static and the dynamic forces.

Case 1 Vehicle stowed in Fore and Aft direction:

The forces preventing tipping of the vehicle are the vertical downward force and the lashings

holding the vehicle (FLT)

Taking moments about A (the outer edge of wheel i.e., fulcrum position)

FLT x L = (1.0 W x 2/3 H) (1.4 W X)

FLT x (X + Y) sin = W (0.67 H 1.4 X)

FLT = (W (0.67 H 1.4 X) / ((X + Y) sin)

Note the importance of the fulcrum position (A),

The height of the centre of gravity, normally taken as 2/3 H

is the angle of inclination of the lashings

To examine the force causing the vehicle to slide sideways:

For this example a trailer is supported by wheels on the one end and with a trestle at the

other end.

In both cases sliding is resisted by the frictional resistance between the tyre/ deck and

the trestle/ trailer frame and also lashings (FLS).

Case 1 Effect at the trestle end of trailer.

Note: Assuming total forces act at each end of trailer then effective sliding force = 0.5 W

0.7 W x Ls (assume 0.2)

= 0.5 W 0.14 W

= 0.36 W then the force in the lashing resisting sliding = FLS = 0.36 W / cos

Case 2 Effect at wheel end of trailer.

Effective sliding force = 0.5 W 0.7 W x (assume 0.4)

= 0.5 W 0.28 W

= 0.22 W

then the force in the lashing resisting sliding = FLS = 0.22 W / cos

Note the importance of the coefficient of friction and the angle of inclination of the

lashings. In the above it can be seen near vertical lashing is great to prevent tipping but is

useless for sliding whereas a near horizontal is great for sliding but is useless for tipping. So a

correct angle of inclination should be fixed appropriate for the cargo.

In general the safe working load (S.W.L.) of lashing wires is taken as 1/3 the Breaking load.

If chain is used for lashing then:

If made of H.T. steel then the SWL would be 40% of the Breaking load.

And if made of ordinary steel then the SWL would be 33% of the Breaking load.

Efficient securing of cargoes is essential for the safety of the ship as well as the cargo

Securing of cargo is of prime importance not only for the cargoes themselves but also for the

ship as a whole including the crew that sail on her.

Improperly secured cargo will shift in a seaway and can endanger the cargo as well as the

ship.

In the worst cases the cargo may fall overboard and may endanger other ships such cargoes

like logs and containers have been noted to have floated and come within the sea-lanes.

When a container falls overboard it must be remembered that it does so in spite of it being

secured on the ship as well as the opposition to this being offered by the ship structure. Thus

when it does go overboard it does after causing a great amount of structural damage.

There are many instances of cargo improperly secured breaking the lashings and punching a

hole at or below the waterline and the ship having been lost with casualties.

Deck cargos if they part their lashings are liable to cause extensive damage, which can

endanger the watertight integrity. Even minor movement of heavy cargoes has been known

to shear off air pipes and sounding pipes resulting in water entering the tanks or other

spaces below deck. Fire lines have also been damaged due to inadvertent movement of

cargo.

Accommodation ladders as well as companionway can be damaged due to the cargo

movement on deck in a seaway.

Even if the ship is not lost the damage such heavy cargoes can bring upon the structure of

the ship is very heavy. Crew has often been sent to re-secure such cargo in rough weather

with the crew suffering loss of limbs and other injuries.

Stowage and securing of deck cargo should be adequate for the worst conditions which

could be experienced

Good stowage and good securing arrangement should be foreseen prior loading the cargo. If

it is required extra lugs and eyes on deck have to be welded to provide lashing points for the

cargo- this is generally done for heavy lifts or cargoes of odd sizes.

Securing should be always for the worst weather that would be encountered. Many a ship

have suffered damage to cargoes and to their own structure by neglecting good and

adequate lashing while on a short voyage, failing to take into account diversions and

anchorage at open roadstead and cyclonic weather.

Hatches should be securely closed and cleated before loading over them

Once the cargo below deck has been loaded and all securing has been completed (securing

can continue after the hatches are secured provided there is adequate space for the crew to

enter and to lash), the hatches are closed and battened down and all cleats and centre

wedges should be in place.

Only after the above have been completed should any cargo be loaded on to the hatch tops.

If this is not done, and the hatch is battened down after the cargo has been loaded on to the

hatch tops the battening down and the fitting of the cleats as well as the centre wedges

would be ineffective since the weight of the cargo would not permit the hatch covers to be

correctly in place and the hatch would leak in a seaway or even in rain.

Deck Cargo

Cargo which are normally carried on deck include the following but are not limited to these

and many exceptional cargoes may be carried and also have been carried in the past.

Dangerous cargo IMDG cargo not permitted on deck

Large packages which due to any size restriction may have to be loaded on to the deck

The above includes engineering or construction equipment

Odd size package

Where the bulk volume far exceeds the weight of the cargo knocked down bridges, port

equipment not easily liable to weather damage.

Occasionally livestock in limited numbers

Onions or other perishables short voyages with the weather holding

Yachts luxury boats.

Cast iron goods man hole covers pipes.

The list is endless and it all depends on the routes, the trading pattern and the weather.

The cargo whether on deck or under deck stow has to be stowed well and the cargo should

be prevented from moving and gaining enough momentum to part lashings and damage the

ship structure.

Deck cargo is liable to damage itself fall overboard and thus be lost. However the misery

does not stop here in the act of parting lashing and going overboard the deck cargo

unleashes considerable damage to the ship structure as well as the crewmembers.

Small apparently insignificant items such as sounding pipes and air pipes are often torn out

and this may endanger the ship from the resulting chances of flooding lower down

compartments.

Crewmembers ordered to lash cargo where the lashings have parted have been seriously

injured and some have lost lives combating the shifting cargo.

The point is to have a good solid stow prevent the cargo from shifting and gaining

momentum with the shift. Since this would part any strong lashing. The lashing undertaken

should be for the worst sea condition that may be experienced.

Deck cargo loading on top of hatch covers should be carefully planned. All loading of under

deck spaces should have been completed lashing may continue with portable lights.

The hatch covers should be closed and battened down all side wedges as well as cross

wedges (centre wedges) should have been fitted. With the hatch cover sealed for sea, the

space should then be given out for loading of deck cargo.

The permissible load density of the hatch covers should be checked and timbers laid to

spread the weight of the cargo. The load density of the hatch covers are given for a new

vessel and as the ship ages the load density would reduce due to fatigue of the metal as well

as wear and tear. Thus the utmost need to spread the weight using timber.

Shoring and toming of the hatch cover from below deck is practically useless since the hatch

cover moves/ slides somewhat with the motion of the ship.

The height of the cargo on the hatch covers as well as that on deck should not be so high

that the view is obstructed from the Navigating Bridge.

Ice accumulation on hatch cover and on deck

The above photographs show the extent of the weight that Ice accumulation can pose for a

ship. The weight on deck may eventually lead a ship to progress to a condition of angle of

loll.

The weight of the ice may be in excess of a hundred tonnes, and thus the danger of a ship

regarding stability.

As with the above any deck cargo for that matter would have a very high KG as such the GM

(F) would be quite small. Especially in the case of GC vessels, which do not have a very large

GM (F) the loading of deck cargo, is bound to lead to further loss of GM (F). If the ship loads

the deck cargo with her own gear then the ship would during the loading operation have still

further low GM (F) due to the KG of the load being at the top of the derrick/ crane for part of

the loading sequence.

Containers on deck

Containers when they are loaded on deck are subject to the following consideration

barring stability, which would have been planned for.

The load density of the deck

Spreading the load of the container evenly

Chocking the container base to prevent shifting due to rolling or pitching

Lashing the container for the above as well to prevent the container from being bodily lifted.

Placing the containers in as close a group as possible

Safeguarding the sounding pipes and the air pipes within the periphery of the container

space.

Keeping the fire hose boxes clear as well as the passage leading to them, the fire hydrants

should similarly be kept clear.

No lashing should be taken which would damage or cause to be damaged the fire lines.

Checking that the leads for the lashing wires are adequate as well as that the chocking points

are well supported

Keeping a passage for crew members to check the lashings during g voyage.

In general the close stow is difficult on GC vessels where the container is usually loaded

between the hatch coaming and the bulwark. So the container should be loaded as close as

possible to the hatch coaming, as well as close to the Mast House structure. If few

containers are being loaded then the shelter offered by the Mast House structure should be

kept in mind.

The load is spread by having the container loaded onto timbers at least 4 x 4. The timbers

should be extended to well beyond the shoe of the container in all directions to spread the

load. Once this is done the chocking of the container is started. Again heavy timbers are used

and the container is first secured to prevent any lateral and transverse shifting. While

selecting chocking points all heavy framework should be selected. Bulwark stays are not

strengthened enough to be used as chocking points. Hatch coamings may be used and as a

last resort bulwark stays. After the chocking is completed the container is lashed. The lashing

is further to prevent the longitudinal as well as the transverse shifting. For this the base

shoes offer the best lashing points. To prevent the container being bodily shifted out the

lashings are continued to the top shoes.

All lashing should be separate in the sense that a single lashing wire should not be passed

over a few shoes and then lashed at the final point. Each lashing should have a turnbuckle or

bottle screw incorporated and there should be at least 60% free thread in them after

completion of lashing.

The bottom lashing and the top lashing should not be counted together fore the purpose of

assessing the total number of lashings taken for the container.

The top lashings are for bodily rise and as such should be counted separately.

As a thumb rule, if the SWL of the lashing wire is 2T then to lash the top of a 20T container

the number of lashings should be a minimum of 10 (all well positioned), similarly the bottom

should have 10. The bottom lashings may be reduced depending upon the chocking of the

container and the availability of the lashing point.

Note that a single strong point for lashing should not have more than 2 lashing wires the

preferred would be 1, however it is often impossible to find so many lashing points.

This shows a container ship lashing; note that the container is loaded onto the ship shoe

slots which are strengthened, the rod lashings are only for the top of the containers.

Here the bottom shoes are not lashed since the ships sunken shoes and twist locks

effectively chock and lash the bottom of the container.

Stowage and Lashing of Timber deck cargoes as laid down by IMO code of Safe Practice for

Ships Carrying Timber Deck Cargoes

Purpose

The purpose of the Code is to make recommendations on stowage, securing and other

operational safety measures designed to ensure the safe transport of mainly timber deck

cargoes.

Application

This Code applies to all ships of 24 m or more in length engaged in the carriage of timber

deck cargoes. Ships that are provided with and making use of their timber load line should

also comply with the requirements of the applicable regulations of the Load Line

Convention.

Timber means sawn wood or lumber, cants, logs, poles, pulpwood and all other type of

timber in loose or packaged forms. The term does not include wood pulp or similar cargo.

Timber deck cargo means a cargo of timber carried on an uncovered part of a freeboard or

superstructure deck. The term does not include wood pulp or similar cargo.

Timber load line means a special load line assigned to ships complying with certain

conditions related to their construction set out in the International Convention on Load Lines

and used when the cargo complies with the stowage and securing conditions of this Code.

Weather deck means the uppermost complete deck exposed to weather and sea.

The stability of the ship at all times, including during the process of loading and unloading

timber deck cargo, should be positive and to a standard acceptable to the Administration. It

should be calculated having regard to:

The increased weight of the timber deck cargo due to:

Absorption of water in dried or seasoned timber, and

Ice accretion, if applicable;

Variations in consumables;

The free surface effect of liquid in tanks; and

Weight of water trapped in broken spaces within the timber deck cargo and especially logs.

Safety precautions to be taken as far as stability of the ship is concerned

The master should:

Cease all loading operations if a list develops for which there is no satisfactory explanation

and it would be imprudent to continue loading;

Before proceeding to sea, ensure that:

The ship is upright;

The ship has an adequate metacentric height; and

The ship meets the required stability criteria.

Ships carrying timber deck cargoes should operate, as far as possible, with a safe margin of

stability and with a metacentric height which is consistent with safety requirements but such

metacentric height should not be allowed to fall below the recommended minimum.

However, excessive initial stability should be avoided as it will result in rapid and violent

motion in heavy seas which will impose large sliding and racking forces on the cargo causing

high stresses on the lashings. Operational experience indicates that metacentric height

should preferably not exceed 3% of the breadth in order to prevent excessive accelerations

in rolling provided that the relevant stability criteria are satisfied.

This recommendation may not apply to all ships and the master should take into

consideration the stability information obtained from the ships stability manual.

STOWAGE

General

Before timber deck cargo is loaded on any area of the weather deck:

Hatch covers and other openings to spaces below that area should be securely closed and

battened down;

Air pipes and ventilators should be efficiently protected and check valves or similar devices

should be examined to ascertain their effectiveness against the entry of water;

Accumulations of ice and snow on such area should be removed; and

It is normally preferable to have all deck lashings, uprights, etc., in position before loading on

that specific area. This will be necessary should a preloading examination of securing

equipment be required in the loading port.

The timber deck cargo should be so stowed that:

Safe and satisfactory access to the crews quarters, pilot boarding access, machinery spaces

and all other areas regularly used in the necessary working of the ship is provided at all

times;

Where relevant, openings that give access to the areas can be properly closed and secured

against the entry of water;

Safety equipment, devices for remote operation of valves and sounding pipes are left

accessible; and

It is compact and will not interfere in any way with the navigation and necessary working of

the ship.

During loading, the timber deck cargo should be kept free of any accumulations of ice and

snow.

Upon completion of loading, and before sailing, a thorough inspection of the ship should be

carried out. Soundings should also be taken to verify that no structural damage has occurred

causing an ingress of water.

On ships provided with, and making use of, their timber load line, the timber deck cargo

should be stowed so as to extend:

.1 over the entire available length of the well or wells between superstructures and as close

as practicable to end bulkheads;

.2 at least to the after end of the aftermost hatchway in the case where there is no limiting

superstructure at the aft end;

.3 athwartships as close as possible to the ship sides, after making due allowance for

obstructions such as guard rails, bulwark stays, uprights, pilot boarding access, etc., provided

any area of broken stowage thus created at the side of the ship does not exceed a mean of

4% of the breadth; and

.4 to at least the standard height of a superstructure other than a raised quarterdeck.

The basic principle for the safe carriage of any timber deck cargo is a solid stowage during all

stages of the deck loading. This can only be achieved by constant supervision by shipboard

personnel during the loading process.

SECURING

General

Every lashing should pass over the timber deck cargo and be shackled to eye plates and

adequate for the intended purpose and efficiently attached to the deck stringer plate or

other strengthened points. They should be installed in such a manner as to be, as far as

practicable, in contact with the timber deck cargo throughout its full height.

All lashings and components used for securing should:

.1 possess a breaking strength of not less than 133 kN;

.2 after initial stressing, show an elongation of not more than 5% at 80% of their breaking

strength; and

.3 show no permanent deformation after having been subjected to a proof load of not less

than 40% of their original breaking strength.

Every lashing should be provided with a tightening device or system so placed that it can

safely and efficiently operate when required. The load to be produced by the tightening

device or system should not be less than:

.1 27 kN in the horizontal part; and

.2 16 kN in the vertical part.

NOTE: 1 Newton equals 0.225 lbs. force or 0.1 kgf.

Upon completion and after the initial securing, the tightening device or system should be left

with not less than half the threaded length of screw or of tightening capacity available for

future use.

Every lashing should be provided with a device or an installation to permit the length of the

lashing to be adjusted.

The spacing of the lashings should be such that the two lashings at each end of each length

of continuous deck stow are positioned as close as practicable to the extreme end of the

timber deck cargo.

If wire rope clips are used to make a joint in a wire lashing, the following conditions should

be observed to avoid a significant reduction in strength:

.1 the number and size of rope clips utilized should be in proportion to the diameter of the

wire rope and should not be less than four, each spaced at intervals of not less than 15 cm;

.2 the saddle portion of the clip should be applied to the live load segment and the U-bolt to

the dead or shortened end segment;

.3 rope clips should be initially tightened so that they visibly penetrate into the wire rope

and subsequently be retightened after the lashing has been stressed.

Greasing the threads of grips, clips, shackles and turnbuckles increases their holding capacity

and prevents corrosion.

Uprights

Uprights should be fitted when required by the nature, height or character of the timber

deck cargo.

When uprights are fitted, they should:

.1 be made of steel or other suitable material of adequate strength, taking into account the

breadth of the deck cargo;

.2 be spaced at intervals not exceeding 3 m;

.3 be fixed to the deck by angles, metal sockets or equally sufficient means; and

.4 if deemed necessary, be further secured by a metal bracket to a strengthened point, i.e.,

bulwark, hatch coaming.

Loose or packaged sawn timber

The timber deck cargo should be secured throughout its length by independent lashings.

The maximum spacing of the lashings should be determined by the maximum height of the

timber deck cargo in the vicinity of the lashings:

.1 for a height of 4 m and below, the spacing should be 3 m;

.2 for heights of above 4 m, the spacing should be 1.5 m.

The packages stowed at the upper outboard edge of the stow should be secured by at least

two lashings each.

When the outboard stow of the timber deck cargo is in lengths of less than 3.6 m, the

spacing of the lashings should be reduced as necessary or other suitable provisions made to

suit the length of timber.

Rounded angle pieces of suitable material and design should be used along the upper

outboard edge of the stow to bear the stress and permit free reeving of the lashings.

Logs, poles, cants or similar cargo

The timber deck cargo should be secured throughout its length by independent lashings

spaced not more than 3 m apart.

If the timber deck cargo is stowed over the hatches and higher, it should, in addition be

further secured by:

.1 a system of athwarthship lashings (hog lashings) joining each port and starboard pair of

uprights near the top of the stow and at other appropriate levels as appropriate for the

height of the stow; and

.2 a lashing system to tighten the stow whereby a dual continuous wire rope (wiggle wire) is

passed from side to side over the cargo and held continuously through a series of snatch

blocks or other suitable device, held in place by foot wires.

The dual continuous wire rope should be led to a winch or other tensioning device to

facilitate further tightening.

Testing, examination and certification

All lashings and components used for the securing of the timber deck cargo should be

tested, marked and certified according to national regulations or an appropriate standard of

an internationally recognized standards institute. Copies of the appropriate certificate

should be kept on board.

No treatments, which could hide defects or reduce mechanical properties or strength,

should be applied after testing.

A visual examination of lashings and components should be made at intervals not exceeding

12 months.

A visual examination of all securing points on the ship, including those on the uprights, if

fitted, should be performed before loading the timber deck cargo. Any damage should be

satisfactorily repaired.

Lashing plans

One or more lashing plans complying with the recommendations of this Code should be

provided and maintained on board a ship carrying timber deck cargo.

Personnel Protection And Safety Devices

During the course of the voyage, if there is no convenient passage for the crew on or below

the deck of the ship giving safe means of access from the accommodation to all parts used in

the necessary working of the ship, guard lines or rails, not more than 330 mm apart

vertically, should be provided on each side of the deck cargo to a height of at least 1 m

above the cargo. In addition, a lifeline, preferably wire rope, set up taut with a tightening

device should be provided as near as practicable to the centreline of the ship. The stanchion

supports to all guard rails or lifelines should be spaced so as to prevent undue sagging.

Where the cargo is uneven, a safe walking surface of not less than 600 mm in width should

be fitted over the cargo and effectively secured beneath, or adjacent to, the lifeline.

Where uprights are not fitted, a walkway of substantial construction should be provided

having an even walking surface and consisting of two fore and aft sets of guard lines or rails

about 1 m apart, each having a minimum of three courses of guard lines or rails to a height

of not less than 1 m above the walking surface. Such guard lines or rails should be supported

by rigid stanchions spaced not more than 3 m apart and lines should be set up taut by

tightening device.

As an alternative a lifeline, preferably wire rope may be erected above the timber deck cargo

such that a crewmember equipped with a fall protection system can hook onto and work

about the timber deck cargo. The lifeline should be:

.1 erected about 2 m above the timber deck cargo as near as practicable to the centreline of

the ship;

.2 stretched sufficiently taut with a tightening device to support a fallen crewmember

without collapse or failure.

Properly constructed ladders, steps or ramps fitted with guard lines or handrails should be

provided from the top of the cargo to the deck, and in other cases where the cargo is

stepped, in order to provide reasonable access.

Action To Be Taken During The Voyage

Tightening of lashings

It is of paramount importance that all lashings be carefully examined and tightened at the

beginning of the voyage as the vibration and working of the ship will cause the cargo to

settle and compact. They should be further examined at regular intervals during the voyage

and tightened as necessary.

Entries of all examinations and adjustments to lashings should be made in the ships

logbook.

Container Cargo

Sea Containers were invented in the mid 1950s by Malcolm McLean, a North Carolina

trucking owner who grew tired of wasting his trucking companys time with trucks standing

idle in line as ships were unloaded bit by bit by dockworkers.

McLean developed sealed truck trailers and the concept of loading and unloading the trailer

interiors only at the points of origin and destination.

The first ship modified to accept these containers on deck, sailed with 58 of them from New

York to Houston in April 1956. This was the start of McLeans company, the Sea-Land

Corporation.

The Matson Line (Hawaii) put the first fully containerized ship into service in 1960.

The International Standards Organization (ISO) first established container standards in 1961.

The ISO standard is not prescriptive and instead simply stipulates tests that the containers

must pass.

Modern container ships have only one problem when the ship arrives in port, the object is to

unload the containers quickly to get them on to their final destination and to get the container

ships back out to sea fully loaded heading for the next port.

To accomplish this, container ships are equipped with steel skeletons called cell guides.

A special lifting fixture is used with remote actuators, which engage the corner blocks on the

top of the container.

A recent survey indicates that port crane operators can execute full crane cycles to remove

and position containers at rates of between 30 and 60 boxes per hour.

Containers come in two basic sizes 20 Footer and 40 Footer and are commonly known as

TEU (Twenty Equivalent Units) and FEU (Forty Equivalent Units).

The external body of the container is made of corrugated sheet metal and is not capable of

taking any load. The four corners have shoes and are strengthened to take in load.

The inside bottom has a wooden ceiling. There are weather-insulted vents provided to

facilitate venting.

The weights marked on the containers are TARE weight and LADEN weight. TARE weight

is the weight of the empty container and is usually 2200KGS for a TEU, while the LADEN

weight may be anything from 20000KGS to 32000KGS (strengthened steel construction).

The container shoes fitted at the corners are hollow with 5 oval slots to facilitate the fitting of

container fittings as well as for lifting the container either by using conventional wire slings

or by spreaders.

Since the containers are concentrated weights the loading of the same require special heavy

dunnaging to spread the load evenly over the deck if carried as deck cargo on conventional

general cargo ships.

However the carriage of containers are primarily on container ships or on ships, which have

been built to take in general cargo as well as containers to a limited extent.

Lashing of containers on purpose ships are supplied from reputed lashing makers and have

been tested for the loads they are to lash. Various fittings are used and all of these are

generally carried on board.

Base stacker Twist Lock Double Stacker

Corner Eye Pad Side Stack Thrust Bridge

Fitting

Twist Lock Rod Lashing Bar Spacer Stacker

A spacer stacker is used where there is a difference between adjacent containers as loaded in

their heights, one being the 8ft and the other 8.5FT.

On normal ships where these fittings may not be available wire ropes are used however the

number of ropes to be used would be decided by the weight of the container.

On GC ships with no provision for built in shoes only single height loads are carried.

However on container ships the hold stacks may extend to 7 high and on hatch top/ deck to 5

high.

The hold and the deck/ hatch top being strengthened.

The lashings to be done are specified in the container-lashing manual supplied to the ship

from the building yard. This is not to be reduced since the stresses have been calculated and

the number of lashings incorporated.

The containers are loaded onto a container ship in a specified manner. The ship is divided into

BAYS or ROWS. Looking from the side the bays are marked from forward to aft.

The containers are stacked in tiers and are in general called the stacks.

This way ensures that any container can be located very easily knowing the bay number and

the row number isolates the location and the stack height give the exact position of the

container.

On container ships the containers are lowered onto slots inside the holds, the holds bottom is

provided with sunken shoes, twist locks/ stackers are fitted onto these and the container is

lowered onto them.

Cell Guides on Deck Open hatch concept:

Some containers are designed to carry refrigerated cargo, these special containers have their

own cooling plant in built on one end of the container, and all that is required for the ship to

provide is a power point for the electricity. The containers come with their own recording

device and card, the ships officers has to renew the card on the expiry of the same, and is to

see that the cooling plant does not stop functioning, manuals are provided whereby ships staff

can do some minor repairs to the plant.

Today a variety of cargo which previously was thought could only be loaded onto a general

cargo ship, is transported on container ships. An example is a tank, thus small parcels of

liquid is carried on container ships.

Lashing of containers is very important since a typical container ship has a low GM(F),

consequently the ship rolls quite a bit and the stresses developed by the cargo swaying is

liable to break the lashings and put the containers into the sea.

All lashings are to be done following the ships lashing manual. In general the following is a

typical lashing system, others may also be accepted if permitted by the manual.

The planning of loading of a container ship is normally undertaken ashore, but the officer in

charge of the watch should keep an eye on the loading to detect errors in stowage which may

occur. A particular watch should be kept for containers with dangerous goods placards to see

that their stowage satisfies segregation requirements as laid down in the IMDG code.

Other things to watch for are that container marked for underdeck stowage do not end up on

deck this is serious since the container may be for second port by rotation, also the heavier

containers are generally loaded underdeck to increase the GM. Thus in addition to a loss of

GM the ship would also have a mess up at the disport.

Refrigerated containers should be loaded where they can be connected to the ships power

supply and the duty officer is to ensure the same. While loading a slight slackening of watch

can become a liability since the gantries load very fast and to unload or to shift is expensive

and time consuming even if the fault actually is of the port.

Sometimes containers are loaded which due to the nature of the contents have to be

overstowed, in this case the container is loaded and the container is then blocked off so that

there would be no chance of any pilferage such containers may carry currency/ coins,

drugs, and mail or other high value cargo.

Bulk Cargo (Not Grain)

Bulk cargoes (other than grain)

The officer of the watch should know the pre-planned loading procedure regarding quantities

to be loaded in each space, the order of deballasting tanks and shifting the vessel under

loading chutes. The procedure will have been worked out to keep stresses within acceptable

limits and to finish with a satisfactory weight distribution and trim. The officer of the watch

should see that the plan is followed, particularly at berths with only one loading chute, to

avoid over-stressing the ship.

Code of Safe Practice for Solid Bulk Cargoes BC Code is intended to set a standard for the

safe stowage and carriage of solid bulk cargoes.

This Code is a recommended guide for ship owners, shippers and masters and shall apply to

all shipments of bulk cargoes.

The list of products appearing in the Appendices of the BC Code, however, is by no means

exhaustive. Consequently, before any bulk cargo is loaded, it is essential to ascertain

(normally from the shipper) the current physical and chemical properties of the cargo, as

required under SOLAS Chapter VI.

General requirements

Before and during loading, transport and unloading of bulk cargoes, all necessary safety

precautions including any regulations or requirements should be observed, including the

following:

1. Dangerous Bulk Material Regulations

2. Safe Working Practices Regulations

3. International Maritime Dangerous Goods Code (IMDG Code)

4. Emergency Procedures For Ships Carrying Dangerous Goods

5. Medical First Aid Guide for Use in Accidents Involving Goods (MFAG)

6. IMO BC Code - Code of Safe Practice for Solid Bulk Cargoes

Poisoning and asphyxiation hazards

Certain bulk cargoes are liable to oxidation, which in t urn may result in oxygen depletion,

emission of toxic fumes and self-heating. Other bulk cargoes may not oxidize but may emit

toxic fumes.

It is important therefore that the shipper inform the master before loading of the existence

of any chemical hazards. The master should refer to Appendix B of the BC Code and take the

necessary precautions, especially those pertaining to ventilation.

Certain cargoes may emit toxic gases when wetted. In these cases the ship should be

provided with the appropriate gas detection equipment.

A flammable gas detector is only suitable for testing the explosive nature of gas mixtures.

Emergency entry into a cargo space should be undertaken only by trained personnel wearing

self-contained breathing apparatus, and protective clothing if considered necessary, always

under the supervision of a responsible officer.

In the event of emergency entry into a cargo space, in addition to the above requirement,

spare self-contained breathing apparatus, safety belts and safety lines should be readily

available.

Health hazard from dust

To minimize the chronic risks from exposure to the dust of certain materials carried in bulk, a

high standard of personal hygiene for those exposed to the dust cannot be too strongly

emphasized. The precautions should include not only the use of appropriate protective

clothing and barrier creams when needed but also adequate personal washing especially

before meals, and laundering of outer clothing.

Flammable atmosphere

Dust created by certain cargoes may constitute an explosion hazard, especially, during

loading, unloading and cleaning. This risk can be minimized at such times by ensuring that

ventilation is sufficient to prevent the formation of a dustladen atmosphere and by hosing

down rather than sweeping.

CARGOES THAT MAY LIQUEFY (section 7 of the BC Code)

Properties, characteristics and hazards

Cargoes that may liquefy include concentrates, certain coals and other materials having

similar physical properties. Appendix A of the BC Code contains a list of such cargoes, which

generally consist of a mixture of small particles in contrast with natural ores that include a

considerable percentage of large particles or lumps.

Section 5 of the BC Code - Trimming Procedures

At moisture content above that of the transportable moisture limit, shift of cargo may occur

as a result of liquefaction.

The major purpose of the sections of this Code dealing with these cargoes is to draw the

attention of masters and others to the latent risk of cargo shift, and to describe the

precautions deemed necessary to minimize this risk.

Such cargoes may appear to be relatively dry and granular when loaded, but may contain

sufficient moisture as to become fluid under the stimulus of compaction and the vibration

that occurs during a voyage.

In the resulting viscous fluid state, cargo may flow to one side of the ship when it rolls one

way, but not completely return when it rolls the other. Thus, the ship sways progressively

until it reaches a dangerous heel and capsizes.

To prevent subsequent shifting, and also to decrease the effects of oxidation of material

with a predisposition to oxidize, these cargoes should be trimmed reasonably level on

completion of loading, irrespective of the angle of repose.

Amended Extract from SOLAS Chapter VI

Part B

Special provisions for bulk cargoes other than grain

Regulation 6

Acceptability for shipment

Concentrates or other cargoes which may liquefy shall only be accepted for loading when

the actual moisture content of the cargo is less than its transportable moisture limit.

However, such concentrates and other cargoes may be accepted for loading even when their

moisture content exceeds the above limit, provided that safety arrangements to the

satisfaction of the Administration are made to ensure adequate stability in the case of cargo

shifting and further provided that the ship has adequate structural integrity.

Prior to loading a bulk cargo which is not a cargo classified but which has chemical properties

that may create a potential hazard, special precautions for its safe carriage shall be taken.

Regulation 7

Loading, unloading and stowage of bulk cargoes

To enable the master to prevent excessive stresses in the ships structure, the ship shall be

provided with a booklet, which shall be written in a language with which the ships officers

responsible for cargo operations are familiar. The booklet shall, as a minimum, include:

.1 stability data,

.2 ballasting and de-ballasting rates and capacities;

.3 maximum allowable load per unit surface area of the tank top plating;

.4 maximum allowable load per hold;

.5 general loading and unloading instructions with regard to the strength of the ships

structure including any limitations on the most adverse operating conditions during loading,

unloading, ballasting operations and the voyage;

.6 any special restrictions such as limitations on the most adverse operating conditions

imposed by the Administration or organization recognized by it, if applicable; and

.7 where strength calculations are required, maximum permissible forces and moments on

the ships hull during loading, unloading and the voyage.

Before a solid bulk cargo is loaded or unloaded, the master and the terminal representative

shall agree on a plan* which shall ensure that the permissible forces and moments on the

ship are not exceeded during loading or unloading, and shall include the sequence, quantity

and rate of loading or unloading, taking into consideration the speed of loading or unloading,

the number of pours and the de-ballasting or ballasting capability of the ship. The plan and

any subsequent amendments thereto shall be lodged with the appropriate authority of the

port State.

Bulk cargoes shall be loaded and trimmed reasonably level, as necessary, to the boundaries

of the cargo space so as to minimize the risk of shifting and to ensure that adequate stability

will be maintained throughout the voyage.

When bulk cargoes are carried in tween-decks, the hatchways of such tween-decks shall be

closed in those cases where the loading information indicates an unacceptable level of stress

of the bottom structure if the hatchways are left open. The cargo shall be trimmed

reasonably level and shall either extend from side to side or be secured by additional

longitudinal divisions of sufficient strength. The safe load-carrying capacity of the tween-

decks shall be observed to ensure that the deck-structure is not overloaded.

The master and terminal representative shall ensure that loading and unloading operations

are conducted in accordance with the agreed plan.

If during loading or unloading any of the limits of the ship are exceeded or are likely to

become so if the loading or unloading continues, the master has the right to suspend

operation and the obligation to notify accordingly the appropriate authority of the port State

with which the plan has been lodged. The master and the terminal representative shall

ensure that corrective action is taken. When unloading cargo, the master and terminal

representative shall ensure that the unloading method does not damage the ships

structure.

The master shall ensure that ships personnel continuously monitor cargo operations. Where

possible, the ships draught shall be checked regularly during loading or unloading to confirm

the tonnage figures supplied. Each draught and tonnage observation shall be recorded in a

cargo logbook. If significant deviations from the agreed plan are detected, cargo or ballast

operations or both shall be adjusted to ensure that the deviations are corrected.

At a moisture content above that of the transportable moisture limit, shift of cargo may

occur as a result of liquefaction.

Many cargoes may appear to be relatively dry and granular when loaded, but may contain

sufficient moisture as to become fluid under the stimulus of compaction and the vibration

that occurs during a voyage.

In the resulting viscous fluid state, cargo may flow to one side of the ship when it rolls one

way, but not completely return when it rolls the other. Thus, the ship way progressively

reaches a dangerous heel and capsize.

Ships other than specialist suited ones shall carry only those cargoes having a moisture

content that is not in excess of the transportable moisture limit as defined in this Code.

Specially suited ships

Specially suited ships may carry concentrates having a moisture content in excess of the

transportable moisture limit if the ship possesses a valid document of approval from her

administration, accompanied by such stability information as her administration may

require. The document of approval must clearly state For carriage of concentrates having a

moisture content in excess of the transportable moisture limit.

When concentrates are loaded that have a moisture content in excess of the transportable

moisture limit, the whole surface area of each cargo space shall be trimmed level.

Cargoes having a moisture content in excess of the flow moisture point shall not be carried

in bulk.

Before loading, the shipper or his appointed agents shall provide to the master and the port

warden, if requested, details, as appropriate, of the characteristics and properties of any

material constituting bulk cargo, such as flow moisture point, stowage factor, moisture

content, angle of repose, chemical hazards, etc. so that any necessary safety precautions can

be put into effect.

To do this the shipper shall arrange, possibly in consultation with the producers, for the

cargo to be properly sampled and tested. Furthermore, the shipper should provide the ships

master and the port warden, if requested, with the appropriate certificates of test, as

applicable for a given cargo.

Before and during loading, auxiliary check tests of the moisture content may be carried out

using instruments designed specifically for that purpose, such as the SPEEDY MOISTURE

TESTER. Tests conducted with this instrument indicate a precision of 1% compared with

the laboratory method, i.e., with a laboratory reading of 10%, the SPEEDY reading could

range from, 9% to 11%. If the readings obtained by this method are consistently higher than

those shown on the certificate, loading of the cargo should cease and a further laboratory

test be conducted.

If the master has doubts as regards the appearance of condition of the cargo for safe

shipment, the following auxiliary method may be used on board ship or at the dockside to

perform a check test for approximately determining the possibility of flow:

Half fill a cylindrical can or similar container (0.5-1 litre capacity) with a sample of cargo.

Take the can in one hand and bring it down sharply from a height of about 0.2m to strike a

hard surface such as a solid table. Repeat the procedure twenty-five times at one or two

second intervals. Examine the surface for free moisture or fluid conditions. If free moisture

or a fluid condition appears, make arrangements to have additional laboratory tests on the

cargo conducted before it is accepted for loading.

COAL is very liable to spontaneous heating. If there is sufficient oxygen available,

combustion is liable to take place. The amount of heating that takes place depends on the

type of type coal and how much heat can be dispersed by ventilating the coal. Ventilation

can be a double-edged weapon as although it takes heat from the coal it also allows

unwanted oxygen into the coal. To keep the coal as cool as possible it should be stowed

away from hot bulkheads. To keep oxygen away from the coal only surface ventilation

should be allowed.

All spar ceiling or cargo battening should be removed as besides the liability of it to damage,

it can give unwanted air pockets in the coal. Unwanted air may also get into a cargo through

a temporary wooden bulkhead. If such a bulkhead has been constructed all cracks should be

sealed, preferably by pasting paper over both sides of the bulkhead.

Freshly mined coal absorbs oxygen, which, with extrinsic moisture, forms peroxides. These in

turn breakdown to form carbon monoxide and carbon dioxide.

Heat is produced by this exothermic reaction causing further oxidation and further heat. If

this heat is not dissipated ignition will occur. This is called Spontaneous combustion.

As this is essentially a surface reaction the smaller the surface available for the absorption of

oxygen the better. Every attempt should be made to prevent undue breakage of the coal

whilst it is being loaded. It may be noted that 1 MT of coal in an unbroken cube has a surface

area of about 3.72m2, whereas if it is broken up to pass through a 1.5mm mesh screen its

surface area is nearly 4000m2. If a large amount of breakage occurs the small coal with the

large surface area is found in the centre of the hold, whilst the large coal will roll down the

sides. This aggravates the situation, as the large coal gives a good path for air to flow to the

smaller coal where the spontaneous heating is most liable to occur.

Most coal fires in cargo occur at about tween deck level and this is the area where the

greatest attention should be paid to temperature and the restriction of through ventilation.

The following are recommendations for the carriage of coal.

The ventilators to the lower holds should be so arranged that they might be opened or

closed at will during the voyage.

As the critical temperature at which the process of spontaneous heating in coal becomes

greatly accelerated is in some varieties of coal as low as 36C, and generally is not much

higher, the need of keeping the exteriors surface of the hull, and thereby the interior of the

tween decks and holds, as cool as possible is manifest.

The iron decks of ships carrying coal in the tropics can be covered with dunnage to lessen

heating.

Suitable means should be provided for ascertaining from time to time the temperature of

the lower mass of coal, particularly below the hatchways, and this might be done by means

of two pipes leading down to the bottom of the coal at each hatchway.

The temperature tubes should have closed ends to prevent admission of air into the cargo.

The temperature of the coal at three heights should be taken daily.

Gas from the holds or tween decks space may find its way into shaft, peaks, chain lockers or

similar space unless the bulkheads and casings are maintained in gas tight conditions.

Naked lights should not be used in holds or other spaces in which gas may accumulate until

the spaces have been well ventilated.

Full use should, when necessary, be made of the breathing apparatus or smoke helmet and

the safety lamp, which form part of the ships statutory fire appliances.

The employment of the crew in chipping and painting below decks during the voyage should

be avoided. The danger from smoking should be realized and no oily waste, wood, old rope,

sacking etc. should be left below where it can become ignited by spontaneous heating

On arrival at the port of discharge the hold ventilators should be unplugged and the lower

hold well ventilated before commencing to work cargo.

Coal is frequently loaded from a single tip and earlier it was necessary to drift the vessel fore

and aft so that all holds may be filled. To keep these shifts to a minimum No.2 was first put

under the tip.

After about one third the capacity of the hold was loaded the vessel was shifted so that No.

3 was loaded to about one third of its capacity. Likewise the remaining after holds were

loaded and then the tip was shifted astern to reach No. 1, half the capacity was put in,

before shifting to No. 2, which was then filled.

The other after holds were now filled in order excepting the aftermost. The aftermost hold

and the No.1 were now worked so that the vessel would complete loading in a good trim.

Coal is sometimes graded, when this in so, care should be taken to prevent undue breakage.

Lowering the first few truckloads into the hold helps as do control of the rate of tipping

down and chute.

Some ports have conveyor belts and an endless bucket system for loading; this is excellent

for graded coal and also keeps the dust down with the ordinary coal.

Fortunately it is mainly the better coals, which are graded, and in generally these are not so

friable.

Coal will need to be trimmed and its angle of repose is quite high, especially if large coal is

loaded.

There is no danger for coal shifting unless it is the very small stuff known as mud coal, slurry

or duff.

This is very fine coal, almost dust, and if the moisture content is high it behaves almost like a

liquid.

Bulk Cargo (Grain)

Loading and Stowage of Bulk Grain

Before loading bulk the following preparations should be done:

Holds and tween deck thoroughly swept down.

All dunnage removed from cargo spaces or stowed at one and covered.

Bilges should be cleaned and sweetened

Bilges suctions should be tested

Tween deck scuppers should be covered with double weave separation cloth, edges to be

fixed with cement.

Any cracks between limber boards to be covered with separation cloth nailed down to

prevent the cargo from going into the bilges.

All pipelines passing through the bilges should be tested and any leaks discovered should be

fixed esp. fire mains, water ballast lines and bilge pumping out lines.

After the holds are swept and if required hosed down, the holds/ compartments are to be

inspected for any infestation.

The inspection should include all easily accessible areas together with inaccessible areas

including under the beams and hatch pontoon frames. In case fumigation is carried out prior

loading then the compartment has to be swept and again inspected for any dead insects and

rodents. The fumigant used should be compatible with the cargo to be carried.

For loading of Rice the fumigation may be carried out twice prior loading and on

completion of discharging.

The inspection for infestation should be very thorough since apart from later claims, some

ports especially in the US, the USDA inspectors would have to clear the ship for loading and

these inspectors are known to be very thorough.

Shifting of cargo

Certain bulk cargos have a tendency to shift and precautions must be taken to counteract

this tendency. These precautions are dealt with below:

Recommendation are made about the stowage of the cargo:

Weight = db (3L+B) tonnes

4.6

where d is the summer load draft

b is average breadth of lower hold

L is length of lower hold

B is the maximum moulded breadth

The height of the cargo pile peak should not exceed:

1.89 x d x S. F. (m3/tonne) metres

Angle of repose

This is the greatest angle from the horizontal to which a substance can be raised without it

shifting. Cargoes most liable to shift are those having a small angler of repose.

Angle of repose of 35 is taken as being the dividing line for bulk cargoes of lesser or greater

shifting hazard and cargoes having angles of repose of more or less than this figure are

considered separately.

Trimming

In compartments entirely filled with bulk grain the grain shall be trimmed so as to fill all the

spaces between the beams and in the wings and ends. In compartments partly filled with

bulk grain the grain shall be levelled whenever practicable.

The provision of a shifting boards or longitude bulkheads within 5% of the vessels moulded

breadth from the centre line or two or more longitudinal bulkheads or shifting boards with a

distance between of not more than 60% of the vessels moulded breadth. In the latter case

suitable sized trimming hatches are to be provided in the wings at intervals of not more than

7.62m., the end hatches being not more than 3.66m from transverse bulkheads.

In holds the shifting boards must extend downwards from the deck at least 2. 44m or

depth of hold whichever is the greater. In tween decks and in feeders, unless there is some

exemption they must extend from deck to deck. If the compartment is only partly filled with

grain, the shifting boards must extend from the bottom of the compartment to at 0.6m

above the surface of the bulk grain, however no shifting boards are necessary if the bulk

grain does not occupy more than of the hold or of the hold where there is a shaft

tunnel.

The Shifting boards must not be less than 50mm in thickness and are to have a 80mm

housing at the bulkhead. They must be adequately supported by wood minimum size

250mm x 50mm or metal uprights with a maximum spacing of 3.96mm and set in 80mm

housings top and bottom. The jointing of 50mm shifting boards must overlap by at least

230mm in way of the uprights.

If the uprights are made sufficiently strong and the length is not too great, shoring or staying

may be unnecessary. If wood shores are used they must be in a single piece securely fixed at

each end and heeled against the permanent structure of the ship, but not directly against

the side plating. The angle between the shore and the horizontal should be kept as small as

possible and must never exceed 45.

The size of the shore is dependent upon its length; a shore over 6.1m in length would be at

least 200m x 150mm. If stays are used they will be fitted horizontally and will consist of

75mm 6 x 12 galvanised flexible steel wire rope, secured with 25mm shackles to uprights

and frames and fitted with 32mm rigging screws in accessible positions.

If the uprights are not secured at the top, the uppermost shore or stay is to be not less than

0.46m from the top.

The vertical spacing of the shores or stays is obtained from tables in the rules.

GM

If a GM after correction for FSC of not less than 0.31m is maintained throughout the voyage

in one or two deck ships or 0.36m in other ships longitudinal bulkheads or shifting boards

are not required in the following positions, (except when linseed in bulk is being carried

therein)

Below and within 2.13m of a feeder which contains not less than 5% of the quantity of grain

in the space it feeds, but only in way a hatchway,

In feeders as above provided that the free grain surface will remain within the feeders

throughout the voyage allowing for a sinkage of 2% of the volume of the compartment fed

and a shift of the free grain surface to 12,

In way of the hatchway where the bulk grain has been saucered, provided that the hatchway

is filled with bagged grain or other suitable bagged cargo. The minimum depth of the bagged

cargo in the centre of the saucer to be 1.83m below the deck level. The grains to be stored

tightly up to the deck head in the other parts of the compartment,

In way of a hatchway in a compartment partly filled with bulk grain.

The surface of grain in a partly filled compartment is to be saucered with a minimum height

of 1.52m of bagged grain or other suitable cargo over the portion where there are no

shifting boards and 1.22m where there are shifting boards. This latter height is also required

when the bulk grain does not occupy more than 1/3 of the hold or of the hold where there

is a shaft tunnel.

The bagged grain shall be carried in sound bags, which shall be securely closed and well

filled. The bags or other suitable cargo shall be supported on suitable platforms which

consist of strong separation cloths with adequate overlapping or 25mm boards spaced not

more that 100mm apart laid on bearers not more than 1.22m apart.

Feeders are to be fitted to feed compartments entirely filled with bulk grain, except in deep

tanks not over moulded breadth of vessel in case GM c above.

They are to contain not less than 2% of the quantity of grain carried in the compartment,

which they feed. The boarding may be horizontal or vertical but must be sufficiently

supported by binders, shores or stays as laid down in the rules. Feeding holes are to be

provided about 0.61m apart in coamings, which extend more that 0.39m below the deck.

The diameter of the hole is 50mm or 88mm depending on coaming depth. Feeders are

assumed to be capable of feeding a distance of 7.62m.

If any part of the compartment is more that 7.62m (measured in a fore and aft line) from the

nearest feeder, the grain in the space beyond 7.62m is to be levelled off at a depth of at

least 1.83m below the deck and the space above is to be filled with bagged grain or suitable

cargo.

Loading two different cargoes in the same hold

Very occasionally, different types of grain are loaded into the same hold. The heavier grain is

loaded first and trimmed level over the entire area of the hold. The surface is covered with

separation cloths/ canvas, allowing for ample overlaps, at least 1m. The cloths are carried

well up the sides and ends of the compartment so that the next grain loaded will force them

against the plating between the frames and stiffeners, it has to be ensured that adequate

leeway is allowed for the separation cloth being taken up the sides and ends of the

compartment, since the lower cargo would settle down during the voyage and if this leeway

is not allowed for the cloth would exert a pull and tear off from the side moorings. This

would result in the cargo being mixed.

The lighter grain should be loaded carefully at first to avoid displacing the separation cloths.

Once the lighter cargo has been leveled off to a height of 0.5m all over the loading may

begin at the usual rate, care being taken to see that it is constantly leveled by adjusting the

loading chute inflow direction.

When bulk grain is carried in the tween deck of a two deck ship or in the upper tween deck

of a ship having more than two decks or above deck the following are to be complied with:

Either the GM shall not be less than that specified in paragraph GM or the total quantity of

bulk grain or other cargo carried in the specified space shall not exceed 28% by weight of the

total cargo below the tween deck.

Partly filled deck area in the above space is not to exceed 93m2,

The spaces which contain bulk grain are to be divided into lengths of not more than 30.5m

by transverse bulkheads, or if not so divided the excess space beyond 30.5m is to be

entirely filled with bagged grain or other suitable cargo.

Vessels having a GM less than that specified in paragraph GM are not permitted to have

more than two holds or compartments partly filled with bulk grain wherein the overstowing

cargo does not fill the space to the deck head. Feeders are not compartments and so they

are exempted from this requirement.

Double bottom tanks used to meet a stability requirement are to be adequately subdivided

longitudinally unless the width of the tank at its length does not exceed 60% of the

vessels moulded breadth.

A grain-loading plan may be supplied to certain ships, which may then be exempted from

some of the provisions outlined above due to their special construction (such as tanker and

bulk carriers), which prevents shifting of the bulk cargo. However, the resulting list of the

vessel must not exceed 5 if the grain settles by 2% and shifts to an angle of 12 from its

original position.

Cargo Care

Inspection of Holds prior Loading:

All holds should be inspected prior commencing loading this may be done while the ship is

enroute or just after completion of discharging and prior loading at the same port.

A thorough cleaning of the hold is undertaken; the bilges are cleaned and tried out with an

amount of water. If required the hold is hosed down and the water pumped to holding

tanks.

This ensures that there is no refuse lying within the holds and that the bilges after loading

would if necessary be capable of being pumped out.

The bilges if with offensive smell have to be sweetened.

This is again a necessity to prevent any food cargo from being tainted.

All other lines in the hold are to be pressed up and checked for leaks. Air pipes and sounding

pipes passing through the hold spaces are to be checked up with a head of water.

The above ensures that ingress of water into the hold is minimized.

The hold bottom has to be inspected for any dents in the plating.

Some DBs may be dedicated for fuel oil/ ballast as such this would give a fair idea if the

plates have set in or if their appears to be a deep indentation/

All spar dunnage at the ship sides are to be fitted and the frames at the sides have to be

inspected.

This is done so that if bale cargo is loaded the shipside steel does not come in contact with

the cargo.

The used lashing material has to be removed including all temporary eyes, which had been

made.

And if this is not done then the same eyes may be inadvertently be used for new lashing

lashing wires are for one use only and the risk of parted lashing arises by using old lashings.

Use of Dunnage

There are basically a few reasons why dunnage is so necessary on general cargo ships while

loading general cargo.

Of prime importance is to keep the cargo away from the steel bottom of the hold. The steel

bottom condenses the moisture in the air and these droplets of moisture over a period of

time can damage cargo. This is known as ship sweat. And only by dunnage can the cargo be

safeguarded against this. Good ventilation certainly helps but some amount of sweat is ever

present.

The second reason why dunnage is spread about on the holds is to bring about some amount

of frictional resistance between the cargo and the steel bottom. Thus lashing becomes

easier. Another factor is the dunnage helps in spreading the cargo weight evenly.

In the event of small ingress of water the dunnage helps in channeling the water into the

bilge wells, if this were not prevented then any accidental ingress of water would be

absorbed or retained in pools by the cargo.

If the hold bottom is dirty due to stain and hard coating of earlier cargo and hosing down is

not possible then a double layer of dunnage would prevent the cargo in coming into contact

with the stain.

In general holds are laid with double dunnage while tween decks are layered with single

dunnage.

The size of the dunnage may vary but usually they are about 6 X 1 X 6 feet. These are laid

about 6 to 10 apart, though the gaps may again vary depending upon the nature of the

cargo. The bottom tier of the hold dunnaging may be laid in the fore and aft direction and

the top tier in the athwart ship direction. At the aft of the hold a clearing of two feet is laid

with the bottom tier in the athwart ship direction. This helps in the water/ condensation

from trickling to aft and then subsequently finding the bilge well.

Tween deck dunnaging is of one tier exceptionally may be two tiers and it really doesnt

make much difference if the dunnage is laid out in the fore and aft direction or in the

athwart ship direction.

For heavy cargo where spreading the weight takes precedence over other hazards, the

dunnage or timber used is generally 4 X 4 X 6 feet (they may be also of stouter variety).

These heavy timbers are laid out in the fore and aft direction in order that the load is spread

on as many frame spaces as possible.

Dunnaging also forms a very important factor when ventilation is of primary concern

especially when loading a consignment of Rice. Extra channels are created within the bagged

cargo to allow good ventilation. Together with double dunnaging being provided between

stacks of 4-6 bags. If this is not done then the cargo sweat that may be generated is not

removed and condenses on the cargo itself allowing the cargo to rot.

Dunnage is used primarily for the protection of the cargo from sweat related damage and

consequently it is used so that the cargo does not get too closely packed thereby obstructing

to the flow of air.

Special cargoes use more dunnage where air channels have to be kept so that the airflow is

not hampered. Rice is one such cargo.

Advantage of dunnaging is also from the fact that it spreads the weight of the cargo evenly

all across the tank top or tween deck top, but this advantage is a side benefit, the main

reason is protection from sweat. And to some extent from heat from the boiler spaces in the

engine room.

Dunnage is thus primarily for the prevention of sweat damage to cargo.

The structure of the ship is made of steel, this steel being a good conductor of heat cools

down faster than wood as such the temperature of the steel may fall below the dew point of

the air within the compartment leading to sweat. However if this steel can be prevented

from coming into contact with the cargo by a layer of wood, which being a poor conductor of

heat does not cool down so drastically, then the effect of the sweat coming into contact with

the cargo and thus damaging the same may be limited.

If despite precautions being taken, sweating does occur, the damage caused may be

minimized by adequate dunnaging of the boundaries of the compartment.

The permanent dunnage of the ships side is known as SPAR Ceiling or CARGO BATTENS. It

consists of timber about 150mm x 50mm fitted over the side frames. It is usually fitted

horizontally into cleats on the frames. There is a vertical distance of not more than 230mm

between the battens. On some ships the spars are fitted vertically and this gives better

protection to the cargo as well as it suffers less damage and is thus more long lasting. Spar

ceiling may also be fitted on the bulkheads at the ends of the compartment; this is especially

the case where the bulkhead is the engine room bulkhead.

The tank top should be covered with a double layer of dunnage. The bottom layer is usually

100mm x 50mm or 150mm x 50mm spaced about 300mm apart and laid athwart ships to

ensure free drainage to the bilges. If the ship has only bilge wells then it is preferable to lay

the dunnage in the fore and aft direction.

The upper layer consists of 25mm boards about 150mm in width laid at right angles to the

bottom layer, about 150mm - 300mm apart.

Occasionally burlap/Hessian is laid over the dunnage - this improves the appearance of the

hold but restricts air circulation through the cargo,

A permanent wooden ceiling more than 65mm thick is often laid on the tank top in the

square of the hatch; this is to protect the tank top and does not replace the dunnaging.

A similar arrangement of dunnage will be found in the tween decks, although double

dunnaging is not so commonly found here. Care should be taken to have a good layer of

dunnage at the ships side over the stringer plate, as water tends to accumulate there.

Secondhand timber is frequently used for dunnage. It should always be inspected to ensure

that it is free of stains, odour, nails and large splinters. New timber also has its drawbacks; it

should be free of resin and should not have a strong smell of new wood.

The top of the cargo is protected by a covering (especially under the stringer plate) by

matting, wood dunnage or some sort of waterproof paper, or plastic sheets.

Single Fore and Aft dunnaging the most common dunnaging:

The second Layer

Contamination of Cargo

Cargoes -which taint easily, e.g. tea, flour, sugar, should be kept well away from strong

smells. If a pungent (strong smelling) cargo e.g. cloves, cinnamon has been carried

previously, deodorizing of the compartment will be necessary.

Dirty Cargoes should never be carried in the same compartment as clean cargoes.

A very general classification for dirty cargoes could include paints and oils, steelwork,

animal products other than foodstuffs. Similarly a general classification of clean cargo could

include food products and manufactured vegetable products e.g. clothing. Naturally there

will be exceptions to both of the above groups.

Reasons for a general inspection of holds

All holds should be inspected prior commencing loading this may be done while the ship is

enroute or just after completion of discharging and prior loading at the same port.

A thorough cleaning of the hold is undertaken; the bilges are cleaned and tried out with an

amount of water. If required the hold is hosed down and the water pumped to holding

tanks.

This ensures that there is no refuse lying within the holds and that the bilges after loading

would if necessary be capable of being pumped out.

The bilges if with offensive smell have to be sweetened.

This is again a necessity to prevent any food cargo from being tainted.

All other lines in the hold are to be pressed up and checked for leaks. Air pipes and sounding

pipes passing through the hold spaces are to be checked up with a head of water.

The above ensures that ingress of water into the hold is minimized.

The hold bottom has to be inspected for any dents in the plating.

Some DBs may be dedicated for fuel oil/ ballast as such this inspection would give a fair idea

if the plates have set in or if their appears to be a deep indentation.

All spar dunnage at the ship sides are to be fitted and the frames at the sides have to be

inspected.

This is done so that if bale cargo is loaded the shipside steel does not come in contact with

the cargo.

The used lashing material has to be removed including all temporary eyes, which had been

made.

And if this is not done then the same eyes may be inadvertently be used for new lashing -

lashing wires are for one use only and the risk of parted lashing arises by using old lashings.

Bilge and Suction Wells

Bilges and bilge wells should be thoroughly cleaned prior loading any cargo and especially if

the previous cargo was oil cakes or such other cargo.

Bilges should be cleaned, the suctions tried out and then the bilges should be sweetened

with pine oil or such. The bilges should be finally dried.

Prior loading of cargo all bilge wells should be cleaned and then filled with water and the

water then pumped out.

Timings for pumping out the water should be noted and compared with the pump efficiency.

While filling the bilge well the sounding as measured by the sounding rod should be checked

against the actual as observed inside the bilge well.

The sounding pipe should be checked for any blockage.

The striker plate underneath the sounding pipe also should be checked for wear down.

Deep Tanks

Deep tanks are tanks on general cargo ships, which are accessible from the hold. The lines

leading to such tanks are to be blanked off since a slight leakage in such lines can damage

cargo in the holds. The man holes to these tanks also has to be ensured that they are water

tight. If any liquid is loaded then the thermometer conduits should be checked for any

leakage as well the heating coils have to be tested prior loading. The pumping out

arrangement has to be tried out before hand.

Covering of Bilge Wells

These suction filters are very easily taken care of. Hessian is used to form a pad comprising

of a double layer and this is wrapped around the loose filter covers of the drain wells. The

pad should not be so thick that it would absorb water and prevent the water from draining

into the wells.

For limber boards the same pads are nailed down between the adjacent boards. And they

then serve the same purpose, that is prevent any debris from clogging up the suctions.

Care of Ballast Lines

This is very important, since the inadvertent ballasting of the deep tanks would damage

cargo loaded in the deep tanks.

There are