MOORING

What is Mooring of Ships?

Since childhood, we have been intrigued by this question: How are ships
‘parked’ upon their arrival in ports, jetties, and piers? Unlike cars, they can’t
simply be put off gear and parking brakes! Ships don’t have brakes in the first
place.
Ships need to be fastened and fixated soundly for conducting all kinds of
shore operations such as cargo loading/unloading, refueling, bunkering,
ballasting/de-ballasting, boarding/deboarding, maintenance, repairing, and
often for idle times based on voyage schedules and berth or workforce
availability. So, mooring or the system of securing a vessel soundly for the
purposes mentioned above is indispensable in studying ships and offshore
structures.

Differences between mooring, docking and

anchoring
It is common to get confused with the terms mooring, docking and anchoring
and may use them interchangeably. But there are stark differences between
them.

Anchoring is the system of securing a vessel amid the sea when the ship is
not near the vicinity of a permanent structure. In other words, when a vessel
requires to be fastened or stranded for various purposes in the deep waters,
anchoring is used so that the vessel does not drift away in the action of
hydrodynamic forces present in various forms. For anchorage or anchoring,
anchors, those heavy weights as old as the history of ships, have been used
for a very long time.

However, in recent times, vessels can be secured anywhere in the seas with
the help of in-situ dynamic positioning systems (DPS), which are automated
systems that can keep the vessel affixed to a particular coordinate without
the help of anchors.

In the traditional systems of anchors, the heavyweight is suspended from the

vessel and is allowed to settle onto the seabed. This fixity of the weight in the
seabed and the resultant high degrees of tension created in the strong
anchoring lines, which are heavy-built lock chains, helps keep the vessel in its
position. The size of the anchors depends on the size of the vessel.

Docking, on the other hand, alludes to the hauling of the vessel entirely away
from the water to a dry area adjacent to the surrounding waters for various
purposes such as maintenance, repair, refitting, or even disposing of an old
vessel. Here, for all practical purposes, the vessel is suitably shifted to an
enclosed area, and the water is then drained off, leading to a dry surface. The
term ‘dry docking’ is often used for repair and maintenance work.
Now, mooring again is the fastening of a vessel to any shore or land-based
structure with the help of suitable mechanisms such that the vessel is not
subjected to free motion. This land-based structure may include berths,
jetties, piers, wharves, quays, etc.

Components of Mooring
The basic components of a typical mooring system are as follows:

Mooring Lines
These are the main components of any mooring system. In earlier times,
ropes were mainly used as mooring lines. However, steel or high-grade
synthetic materials have been widely used. The main requirements of any
mooring line should be high strength and elasticity. The forces transmitted
from the ship structures are transmitted directly to these mooring lines.

The net effect on the lines becomes manifold from this static load coupled
with the random dynamic behavior from the tendency of motions or
environmental loads acting on the ship. So, these mooring lines’ material and
sizes are carefully chosen based on the vessel and the type of mooring
arrangement.
All mooring lines are characteristic of a Safe Working Load or SWL based on
their properties. Like all other structures, these mooring lines have a definite
breaking strength with a safety factor margin. Steel hybrids of high grades
are often used, and common materials such as Polyamide or HMPE are used
for synthetic.

Generally, lower elastic or higher rigid but greater strength lines are used for
larger vessels, and higher elastic or less rigid materials are used for smaller
ships. The reason is that heavier vessels, due to their greater inertia, have a
lesser tendency to respond to external forces and, thus, are less subjected to
random motion parameters than smaller vessels. Therefore, when these lines
have higher flexibility, they can cater to smaller ships more prone to motion
when moored. HMPE and steel have low elasticity, whereas other materials,
such as polyamide, have greater elasticity.

Mooring Winches
On the shoreside, the mooring lines are joined to the winches. These winches
act as end supports for these lines and help in handling and directing the lines
as per requirements. The winch system controls the tension and extension of
the mooring lines. The mooring lines are commonly operated by electro-
hydraulic power that uses hydraulic pressure to control the tension and
traction forces on the lines. The main component of the winches is cable
drums, either oriented horizontally or vertically. The size of the drum once
again depends on the ropes.
Driving Systems
The winches are operated by electrical and hydraulic mechanisms. These are
mainly dedicated engines or motors that supply the power to the winch
through torque. In turn, the power supply is from the shore supply main lines.
These systems’ capacity is as per the capacity and configuration of the winch
and related mooring lines.

Vessel fittings or attachments

At the other end of the mooring lines, they must be tightly secured to the
vessel structure. These attachments are usually on the main deck but can
sometimes be placed in subsequent decks. Once again, based on the type of
vessel, the number, size, type, and configuration of these fittings are present.
The fittings associated with these mooring are all designed and constructed
per standard IACS guidelines based on the vessel and the related mooring
system. Usually, the fitting used are chocks, bollards, fairleads, bitts, etc.

Fenders
Now, despite the mooring lines, vessels often tend towards motion and, as a
result, can be prone to hit on the adjacent shore or dock structure to which it
is secured. Such impacts can result in damage to the shore structure as well
as the vessel. So, for the same reason, the vessel and the shore structure are
padded with a securing arrangement known as fenders, which absorb impact
energy in the event of a collision or strike. The design of the fenders is once
again based on the vessel type and size. They are usually made of rubber,
wood, or high-grade synthetic polymers.

Competence of a mooring system

Now, for a mooring system, the main job is to secure a vessel in its position
when berthed safely and also ensure that the vessel is kept sound from
collisions or damages due to vessel-structure interactions due to external
dynamic forces. Moreover, the mooring arrangement should be such that for
various port or dock operations, there is never a problem. So, for a good
mooring system for a given vessel, the main characteristics can be listed as
follows:

 Symmetrical nature of the vessel and uniformity of position

 Maximum possible resistance against the rotational and translatory
motions of the vessel.
 Uniformity concerning the shore connections or winches such that the
tension forces of the entire mooring arrangement remain more or less in
equilibrium without any mechanical imbalance on both the ship
structure and the shore.
 Maximum space to cater for the minimum motions of the vessel without
any hindrance, how sound the arrangement may be.
 Reliability
 Safety
  Ability to cater continuously round the clock for a single vessel stranded
for a long time or multiple ships coming to be secured at the same
arrangement without structural fatigue or failure.
 The capability remains intact under all weather conditions when the
forces imposed on the lines and the attachments are very high.
 Having provisions for surplus or spares when required or in the event of
a partial failure.

Types of mooring (Based on configuration)

Mooring can be of various types:

 Single-Point Mooring
 Multi-Point Mooring
 Standing Mooring
 Running Mooring
 Mediterranean Mooring
 Canal Mooring

How Baltic Mooring of Ship is Done?

What happens when there is a strong onshore wind and you have to berth a
ship without the assistance of tugs to a pier or jetty that is not strong enough
to bear the impact or is not sufficiently ‘fendered’?
In such a situation, the master or the pilot takes the recourse of using the
ship’s anchor as well as the wires available on board in a specific way to
minimize the impact of the fall. This is done by mooring ship in such a way
where a vessel is berthed alongside the quay by employing a stern mooring
shackled to the offshore anchor cable in the region of the ‘ganger length’.
When approaching the berth, the offshore anchor is deployed and the weight
on the cable and the stern mooring act in unison to hold the vessel just off the
quay.

Baltic mooring is a combination mooring of a vessel alongside the berth which

employs a stern mooring shackled to the offshore anchor cable in the region
of the “ganger length”. When approaching the berth, the offshore anchor is
deployed and the weight on the cable and the stern mooring act to hold the
vessel just of the quay. Baltic mooring is a safe option to berth a ship on a
windy day.
Now, there is a preparatory process to be undertaken before venturing for the
Baltic moor.

– At first a 30 mm wire is passed from the poop deck on the offshore side
from the outside of the hull and clear of any protrusions like the gangway, the
pilot ladder etc.

– The anchor is cockbilled, i.e., released a little from the hawse pipe before
finally letting it go, and a man is lowered with a bosun’s chair (a seat
suspended from the ship to perform any work outside the ship’s hull) to tie up
the wire to the anchor with a shackle at about the ganger’s length.

– The other end of the wire is taken ‘on turn’ upon a mooring winch through a
bight.

– When the ship is abreast of the berth and falling on it rapidly, the anchor is
dropped keeping trickle headway so that the anchor holds.

– When the anchor is snubbed, the wire from the stern that goes in with the
anchor, gets taught and effectively holds the fall of the stern.

– The anchor chain is then slowly payed off and simultaneously the wire from
the stern, while the on-shore wind pushes the vessel horizontally to the berth.

– As soon as the vessel is close -springs, head and stern lines are passed
ashore with the heaving lines and the scope of the anchor adjusted
accordingly so as to bring the ship slowly alongside the berth.

– Normally the anchor is dropped 70-100 feet off the berth depending on the
wind force and the tonnage of the vessel.
Watch the video below to understand the process:

What is a Mooring Buoy?

A buoy is a type of object that floats in water and is used in the middle of the
seas as a locator or as a warning point for ships. Buoys are generally bright
(fluorescent) in color and made of PVC tubing. Some buoys have a sturdy one-
piece polyethylene shell and hard skin shells which act as Ultraviolet light
absorbers with a sandblasted finish.
Mooring buoys are a type of buoy to which ships can be moored in deep
oceanic areas. A mooring buoy weighs more than standard buoys. The
mooring buoy is designed in a manner that there is a heavier weight located
right at the bottom

of the sea. This weight is like an anchor holding the buoy afloat in the water.
A mooring buoy has loops or chains attached to its top that float on the water.
These chains are provided so that ships or boats can be effectively moored to
them.

It is essential to use the mooring equipment correctly. While approaching the

Buoy, the yellow pick-up line should be close. It can be retrieved using the
boat hook.

The vessel’s bow line should be fitted with the loop of the pick-up line. Cleat
the ends of the bow line to the vessel’s bow. The pick-up line should not be
tied to the vessel directly since it stresses the mooring system.

Size of Mooring Buoys

Mooring Buoys come in different sizes and features, depending on the
requirement. Their diameter ranges from 12′ to 30′. Top brands selling
mooring buoys and related accessories include Cal June, Jim Buoy and
Wholesale Marine’s taylor made traditional sur-moor mooring buoy which
supports the mooring line effectively. Taylor Made Shackle Buoys have a rope
nest design in a cup shape at the top of the buoy, enabling the anchor
shackle to remain under the buoy surface.

The entire application of a mooring buoy works in such a way that the buoy is
floating while the ships are moored to very firm support without using the
anchor system to halt a ship. In some parts of the world, mooring buoys are
also used to moor boats and ships away from areas where coral reefs thrive.

Ships using mooring buoys to protect coral reefs do so because when the
traditional types of anchors are used, they tend to dig and uproot the coral
that lies deep under the water’s surface. This would cause a huge loss to the
marine ecosystem.

By using a mooring buoy, two purposes are served – the ships are moored
appropriately and the loss to the marine life-forms is prevented. Such
mooring buoys in coral reef areas are located mainly in Australia, Asia, and
also in some parts of the United States.

The shipping tankers using mooring buoys have to follow regulations set by
the Oil Companies International Marine Forum (OCIMF). This is an official and
voluntary association of companies that engage mainly in oil extraction and
shipping across the world.

Oil tankers use mooring buoys because they are stable and easy when it
comes to unloading the cargo contained in these ships. Instead of a tanker
ship going to an oil rig for loading oil containers, it’s better if this procedure is
carried out on the high seas so that delays are not caused in the
transportation of cargo to the required areas.

A mooring buoy is more preferred to the traditional type of anchors in today’s

times. In the days to come, because of the increase in awareness towards
environmental protection, the system of a mooring buoy will be the most
relevant equipment in the shipping industry.

FAQs About Mooring Buoys

Here are some of the Frequently Asked Questions About Mooring Buoys-

1. What is the purpose of a mooring buoy?

Mooring buoys are placed in waters as warning points for ships, to guide or
warn sailors of dangers ahead, and for preventing the vessel from drifting by
fixing it firmly with the seabed using the mooring line. They also aid in coral
reef conservation.

2. How Does a mooring Buoy work?

Mooring Buoys are floating structures required for mooring cruise ships,
fishing vessels, cargo carriers, and private ships when they are in deep waters
or even shallow waters. The Buoys are fitted to the seabed through mooring
chains or ropes.

3. What does a mooring buoy look like?

Generally, a mooring buoy is circular in shape, painted white with blue or
orange stripes.

4. How are mooring buoys marked?

Mooring Buoys are white with blue horizontal bands allowing ships to moor in
public waters. It is unlawful to tie the vessel to any boat, light markers,
beacons, stakes, flags, or other navigational aids apart from designated
buoys.

5. How are mooring buoys anchored?

Mooring Buoys are designed in a way that the heavyweight is located right at
the sea bottom. This weight acts like an anchor, keeping it afloat on the
water. It has loops and chains attached to its top.

6. Which colours on a mooring buoy?

Mooring Buoys are usually yellow in color along with white with a blue
horizontal band.

6 Common Mooring Methods Used For Ships

Each vessel has been designed with mooring arrangements such that ropes
and wires of recommended strength can help it moor safely alongside a berth,
floating platform, buoy or jetty. Fundamentally a vessel has to be positioned
alongside a jetty or a berth, between mooring buoys, to a mooring buoy, to
another ship or barge and then made fast using her own anchors, mooring
lines or shorelines.

Some very common methods of mooring are Mediterranean mooring,

Baltic mooring, running mooring, standing mooring, Spider mooring
buoys, Single-point or single buoy mooring, Conventional or multi
buoy mooring, Ship to Ship Mooring

While Moored alongside a fixed or floating jetty or a sea berth there are
various forces acting on the vessel such as wind, current, tide, wave action,
swell, surging induced due to passing ships and trim of the vessel.

The spring, breast and headlines prevent the vessel’s movement against the
action of these forces. The directional effect of these need not be
unidirectional. It can be multi-directional or at various angles to the vessel.

The resultant direction of these forces often changes with changes in

direction of onshore/offshore winds or tidal streams, currents upriver and
down streams. Thus, a combination of breast ropes, head ropes and spring
ropes is the best method to counter these forces and keep the vessel safely
alongside.

Often mixed moorings are observed as some terminals based on local

conditions and experiences require vessels to use more lines than they are
designed for. Thus, the method in which wires in conjunction with soft ropes
with different SWL and construction are used as well is termed Mixed
mooring.
The simplified resultant of these forces would tend to move a vessel in the
transverse or longitudinal direction with respect to the jetty. Thus, spring lines
prevent the longitudinal motion and the breast lines check the transverse
motion.

It is always preferred to avoid mixed moorings due to variable loads and

elasticity of various kinds of ropes and wires which lead to different strains or
weights on the lines. This can result in excessive loads on some lines than
others and eventually part them putting the vessel in danger. However, for
safety reasons or in a desperate situation shipmasters or pilots may have to
resort to mixed moorings.

Vessels sometimes also use the seaward anchor in conjunction with

mooring lines to haul the vessel out of the jetty while casting off or
while making fast the vessel alongside use the seaward anchor to
assist the control of the rate of lateral movement towards the berth.
This maneuver can be carried out with or without the assistance of
tugs.

Ship to Ship transfer operation involves mooring alongside two different or

same sized ships for cargo transfer. During this operation, either one of the
ships is at anchor or both are underway.

The mooring arrangement depends on the size of the ships. A vessel either at
anchor or stopped and maintaining a constant heading is approached by the
maneuvering ship at an angle of approach as smaller as practicable. The
region of approach is usually abaft the beam of the constant heading ship.

During the approach as the maneuvering ship comes closer, it steers a course
parallel to the heading or course of the other ship and reduces the horizontal
distance between ships to less than 100 meters. Once this state is achieved
the maneuvering ship uses engine and rudder movements and reduces this
distance further until the fenders touch each other.

The two ships thus then make parallel contact and the lines are passed
respectively as per the mooring plan. As a common practice during the
approach, the wind and sea are preferred to be from ahead or at very small
angles to the bow.
Single buoy or single point mooring: Often larger ships that cannot
approach ports and terminals are berthed outside the port limits or in
sheltered anchorages and the cargo transfer carried out with the help of
Single-point or single buoy moorings.

The basic principle of the buoy is to keep the position of the vessel with
respect to the buoy steady and at the same time allowing vessels to swing to
wind and sea.

Often a tug is provided at the aft to keep the ship at a fixed angle and
distance from the buoy. The buoy is fixed by positioning it in the center of
four anchors connected to it. The ship is made fast to the buoy with the help
of a single chain or two which is secured onboard to the bow stopper.

In general, while approaching Single point or single buoy moorings weather is

a major criterion in determining whether to berth the vessel or not. Calm seas
with low swell and wind force below 15kts are considered favorable to make
an approach. Presence of strong tidal current limits the interval for berthing
and unberthing.

The headway approach has to be slow often less than while at the same time
approaching at a smaller angle to the buoy and then gradually hauling in the
buoy messenger rope and pulling the vessel slowly towards the buoy using
engine kicks at short intervals to control and maintain headway along with
mooring winches to haul in the vessel when she nears about 150-200 meters
from the buoy.

For unberthing the chain is released from the bow stopper and a short kick on
the engines going astern swings the bow to starboard for right-handed
propellers thus clearing the vessel of the buoy. Tug’s assistance can also be
sued to pull the vessel astern and clear it of the buoy.
 Conventional buoy or multi buoy mooring: In this method, the bow
of the ship is secured using both her anchors whereas the stern is secured to
buoy around it. In the approach firstly vessel approaches the final berthing
position from forward at an angle of 90 degrees to her final direction of
berthing.

The starboard anchor is then let go first at a pre-decided spot while the ship is
making headway. The required amount of cable is paid and the astern
propulsion too operated simultaneously to stop the vessel. Once the vessel is
stopped in the water port anchor is let go and thus vessel positions her stern
along the centerline bifurcating the buoys.

For aligning the vessel along this centerline port cable is paid out and
starboard cable heaved in with astern propulsion. The helm and engines are
to be carefully used during this maneuver to ensure the stern is swinging
clear of any of the buoys.

During unberthing, the anchor cables are heaved in to move the vessel
forward and the weight is taken on windward lines while casting off other lines
to prevent swinging of the stern into the other buoys. This maneuver requires
skill and efficient operation of the ship’s crew as well as of the mooring
equipment as often weight of the lines can be immense.

Mediterranean mooring: For this type of mooring, a pre-calculated position

is determined and approached using engine movements. The bow initially is
made to can’t towards the berth and the starboard anchor is let go in that
position.

After this, the engines are run astern and the port anchor is let go at the
designated spot. The vessel falls astern and swings to starboard. Thus, vessel
is held by both the anchors as it approaches the quay. Stern lines are then
passed. Moorings are kept tight by using the anchor cables.

The positioning of the vessel is such that mooring is completed with around
four shackles on each anchor. Often tide is used to control the drift of the
vessel towards the quay while positioning it by heaving or paying out on one
of the anchors.

Running Mooring: This manoeuvre takes a relatively short duration

compared to the Mediterranean mooring and offers more control of the
vessel. The vessel’s starboard anchor is let go at a position approximately
four to five shackles from the final position of the bow and around 9 shackles
paid out while moving ahead on engines.

Then as she falls astern with the tide the port anchor is let go and the
starboard anchor is heaved onto five shackles. This method restricts the
swinging room and reduces the load on the windlass.

Standing Mooring: This is practised during crosswinds. As the vessel is

stopped the port anchor is let go and with the tide around 9 shackles are paid
out. The starboard anchor is let go and simultaneously port anchor heaved
on.

Thus the port anchor is kept on 4 shackles being generally the flood anchor
and starboard on five as it is the ebb anchor. This vessel takes longer duration
and provides less control over the vessel. The load on the windlass is more as
compared to running moor.

10 Important Points For Ship’s Mooring

Equipment Maintenance
Correct operation of the mooring equipment onboard is indeed important for
the overall safe operation of a vessel in port. Mooring, being such a critical
operation, reminds us of the fact that any unforeseen event could
prove dangerous and sometimes fatal.
In order to implement safety and avoiding lives to be at risk, it’s imperative
for ship’s personnel to maintain high standards of integrity of the mooring
equipment. A better way will be to incorporate all the parts of the mooring
equipment into the ship’s planned maintenance system.

Let’s see how to adhere to the maintenance of the mooring mechanisms

onboard –

1. Make Checks Prior Mooring – After an extended sea passage or a

passage undertaken in heavy seas and prior to mooring operation, ensure to
check the following

i. Any physical damages to the mooring mechanism.

ii. All controls, linkages and the operating levers are well oiled, greased
and free / easy to use.

iii. Ensure that all the brake drums and linings are suitably dried and clean
of salt deposits.

2. Do Frequent Greasing of Moving Parts – All rotating parts of the

mooring equipment, which would include rollers, fairleads, winch drums, deck
stands etc. must be moved and lubricated on a frequent basis. Multipurpose
grease is the best lubricant for such applications (check the vessel’s
lubricating chart for the right application). Normally, high pressure grease
guns are used for this kind of work. Particular attention must be given to the
roller fairleads and deck stands as these often suffer from little use and
thereby are neglected. Rollers should turn smoothly and must be checked for
integrity as corrosion may have weakened them.

Tip – Always check the grease nipples before application and make
sure the nipples are free of rust, salt and grit. Change the nipples if
necessary.

3. Check Brake Liners – Regular inspections must be made of the winch /

windlass brake linings for wear and tear. Oil, heavy rust and moisture on the
brake linings or the drums could seriously reduce the brake holding capacity
of the winch and in some cases as much by 75%. To remove the moisture in
the linings, apply the brakes lightly while running the winch (remember to
avoid excessive wear and tear during this operation). Oil has the tendency to
get impregnated into the lining itself which is difficult to remove. Thus the
only option would be to change the lining as early as possible. Remember that
the brake holding capacity of the winch is dependent upon the type of
mooring pattern used.

4. Check Break Drums : Whenever brakes are opened up for any reason,
ensure that the brake drum is thoroughly checked / examined for build up of
rust or other worn out brake material. The part to be de-scaled and fitted with
the replacement as required.

5. Check Brake Linkages – The brake linkages should be checked for free
movement. If the linkages are not free then there would be a loss of brake
holding capacity. This would create a wrong impression to the operator that
the brake has been applied fully, but in fact has not or the brake mechanism
is hardened up from lever bars ,which have a tendency to build up high
stresses on some mechanical parts of the brakes.
6. Inspect Gear / Hydraulic Oil – Inspect the gear oil regularly through the
inspection cover in the winch / windlass. Whitish color of the liquid means the
liquid is contaminated and requires to be changed immediately. Use the
replacement oil that is recommended by the manufacturers.

7. Carry Out Regular Visual Inspection: Ensure that regular inspection of

the synthetic mooring hawsers, heaving lines, messenger ropes, etc. is
carried out for damages, chafed areas, kinks and loose ends. Also make sure
that each mooring rope carries a certificate from the manufacturer.
Additionally, check that the ID number of each certificate is conspicuously
marked / embossed on an identification plate and subsequently attached to
the end of the corresponding mooring hawser. If the hawser is not supplied
with the certificate, then the vessel has all the right to reject such a supply
and inform the office / purchasing department.

8. Clear Walkway: An important part of the mooring operation is to have the

deck completely free of obstructions and oily residues. Therefore, it is
essential to keep the decks clean, dry and if possible have anti-slip paint
coatings over the deck surface, as and how required. Often there have been
cases where the support brackets for the gratings (for winch operation) have
been found neglected and therefore are heavily corroded making the area
most unsafe to step on. Officers should include such neglected yet critical
areas for planned maintenance in order to prevent an unforeseen event when
least expected.

9. Do Proper Marking and Labeling: Marking the mooring equipment is

another important aspect for a safe and effective operation. The ship’s
officers should ensure that the bollards, fairleads, rollers, etc. are marked with
their safe working limits. Additionally, the winches and windlass shall be
marked for rotating direction of the drums (render / heave), braking capacity,
test dates and ID numbers of the equipment subsequent to the certificates
carried onboard.

10. Maintenance of Steel Wire Mooring Ropes – It is essential to grease

and lubricate the steel wire mooring ropes at regular intervals as rust will
reduce the strength of the wire in a very short period of time. Lubricating
such ropes require special grease, normally oil based compounds. An
effective greasing is carried out by removing the entire wire out of its stowed
position and applying the lubricant generously throughout the length of the
rope. It is also important to note that the wire should be turned end to end
regularly to reduce wear and prevent corrosion. Visual inspections are equally
important and should be carried out regularly with special attention to areas
with dark patches. Any wire shall be replaced if it is damaged to the extent
that more than 10% of the visible strands in a length of a wire equal to 8
diameters are broken.

10 Important Points to Remember During Mooring

Operation On Ships
Mooring operation is one of the important tasks that seafarers have to
perform on ship’s deck. Technically, the operation may seem simple but there
are several dangerous associated with it. As a seafarer, you must have heard
about “Death Traps” on ships and how crew members have lost lives during
mooring operation.
Working on the ship’s deck is not an easy task. Deck crew has to consider
various safety precautions and understand working of deck machinery and
systems, along with cargo operation equipment. When it comes to mooring
operations, additional precautions need to be taken to ensure personal and
crew members’ safety.
1. Don’t Allow Any Extra Crew Member on the Deck: Ensure that no
extra personnel are present at the mooring station except those who are
involved in the operation. Anyone who is not assisting in the mooring
operation must be asked to leave the mooring station for his/her and other’s
safety.

2. Consider Weather Condition: Before planning the mooring operation,

consider the weather condition by taking factors such as wind and current.
The ship’s master and responsible officer must have the details of current and
future weather data before commencing the mooring operation.

3. Have knowledge of Snap Back Zone and Rope Bight: All personnel
involved with the mooring operation should be aware of the snap back zones
and rope bight. Click here to know more about this.

4. Check All the Mooring Equipment: Check all the equipment (mooring
winch, drums, windlass etc.) involved in the mooring operation for any kind of
problem. Proper routine maintenance is the key to ensure smooth running of
mooring equipment and systems. Don’t forget to check the load sensors of
mooring winches.

5. Check the Tail of Mooring Line: If the mooring wire line is provided with
tail (short lengths of synthetic fiber rope which are placed in series with the
vessel’s winch-mounted wires to decrease mooring line stiffness and thus to
reduce peak line loads and fatigue due to vessel motions) ensure same size
and material of tails are used for all lines in the same service (breast, spring
and head lines). Different tail size and material would lead to uneven load in
the mooring line.

6. Tend One Line at a Time: Only one line should be tended at a time
during mooring operation. If this is not done, it may increase the load in the
other tended lines. If two lines are tended together it may lead to overloading
and breakage. Follow the orders of the master or responsible ship officer
properly to avoid any kind of mishap.

7. Keep a Check on the Mooring Line Load: Ensure that the allowable
breaking load in any of the mooring lines does not increase 55% of its
Maximum Breaking Load (MBL). This is to prevent the line from breaking.

8. Avoid Mixed Mooring: Mixed mooring is extremely dangerous. Generally,

mooring lines of the same size and material should be used for all leads, if
this is not possible due to the available equipment, all lines in the same
service, i.e. breast lines, spring lines, head lines and stern lines should be of
the same size and material. The use of mixed moorings comprising full length
synthetic ropes used in conjunction with wire should be avoided. If a
synthetic rope and a wire are used in the same service the wire will carry
almost the entire load while the synthetic rope carries practically none.

9. Keep a Continuous Check: Load on the mooring lines must be checked

continuously even after the mooring operation is over. If there is any change
in the ship’s ballast condition, the lines must be slacked or tightened
accordingly. The condition of the rope material should also be checked to
foresee unfortunate accidents.

10. Arrange Mooring Lines Symmetrical: All mooring line must be

arranged as symmetrical as possible with the breast line. The breast line
should be perpendicular to the longitudinal centre line of the ship and the
spring line should be parallel to the longitudinal centre line.