Resultados del análisis de referentes de EDS

3. Watertight Integrity and Heavy Weather Precautions

Heavy weather can be defined as those conditions which pose an increased risk due to:

• Increased stress on the vessel’s structure;

• Difficulty in maintaining the intended course and speed;

• An increased hazard to personnel due to the movement of the vessel;

• Significant risk of inadequately secured objects moving and causing either damage or injury;

• Difficulty in operating machinery;

• Increased difficulty in detecting other vessels or objects in the immediate area;

• Increased fatigue for all seafarers.

The degree to which a vessel is affected by heavy weather is obviously determined by the size of the vessel and the particular combination of wind, sea and swell. The main objective is to ensure that the vessel is prepared before the onset of heavy weather. Ideally, the objective should be to avoid extremes of heavy weather, but frequently, due to the speed of approach of storms or limited sea room, it is unavoidable. All ships are designed to withstand heavy weather, within the limitations of their construction provided that the basics of good seamanship are observed beforehand.

The unexpected ingress of water into, and flooding of, compartments is more often than not caused by a lack of due care and attention and poor seamanship.

The maintenance of all parts of the structure where water can enter, such as door and vent packing, the dogging or sealing arrangements on hatches, and the provision of simple remedies such as on canvas covers where required, are fundamental and basic concepts of good seamanship.

Water ingress can result in a catastrophic loss of buoyancy and the subsequent risk of the loss of the vessel. It invariably results in a considerable amount of work restoring the spaces to their original condition, and in repairing and replacing equipment,

One of the main objectives of ship-handling in heavy weather is to prevent breaking seas coming onboard the ship itself.

3.1 Securing the Vessel for Sea

All seafarers have a collective responsibility to ensure that whenever necessary all spaces which could be subject to water ingress are adequately secured whilst the vessel is at sea, regardless of the current weather conditions.

Every vessel must be fully secured when proceeding to sea from port if there is any doubt as to the weather conditions outside the harbour. Every vessel must also be fully secured each night when the day’s work has been completed. There are to be no exceptions to this requirement.

It is the responsibility of the Chief Officer to ensure that either he or the senior deck rating personally ensure that all spaces have been closed and adequately sealed and that the fact is reported to the bridge. The Watch Officer must record the fact in the Deck Log Book.

In extended periods of bad weather, it is crucial that all spaces, particularly those forward and those accessed from the maindeck, are checked as being dry on a regular basis, and at least once daily. Bilge alarms must not be solely relied upon to warn of water ingress. Particular care must be taken with respect to those spaces not fitted with bilge alarms.

The Master is to take all necessary precautions to protect the welfare of those inspecting exposed areas in bad weather, including considering turning the vessel to provide weather protection. It

is for the Master to judge, in severe weather conditions, whether there is a risk in turning the vessel, and the more prudent course of action might be to delay the inspections.

3.2 Ingress of Water in Heavy Weather

Ingress of water is most commonly experienced in the foc’s’le space, and this area requires particular attention. However, all spaces with the potential for water entry in bad weather must be treated with equal importance and must be secured both each night at sea and on the onset of bad weather.

Water can enter in numerous ways:

• Doors, hatches or vents left open;

• Packing in poor condition. Hard, perished or deeply grooved packing must be replaced;

• Incorrectly fitted packing – the ends of packing must be cut diagonally, not square;

• Painted packing. Paint prevents adequate sealing;

• Incorrect packing. Very hard or very soft packing should generally be avoided;

• The packing retaining track in poor condition, allowing the packing to become dislodged;

• Dogging arrangement in poor condition, preventing the securing of hatches;

• Hatch hinges seized or poorly designed, preventing vertical movement of the hatch cover and resulting in an inability to secure the hatch;

• Vents in a wasted condition, resulting in the vent being washed away;

• Ingress into the chain locker through inadequately sealed spurling pipes, and subsequently through the anchor cable bitter end securing arrangement;

• The fracture or wastage of sounding pipes.

The Chief Officer is responsible for ensuring that all securing arrangements are maintained in good order, in accordance with the planned maintenance system.

The following should be checked at regular intervals:

• The physical condition of doors and hatches, including hinges, dogs and other securing arrangements;

• The condition of packing. Painted, perished, soft, very hard, or deeply grooved packing should be replaced;

• The sealing arrangement for the spurling pipes must be checked as being adequate to prevent water ingress;

• The sealing arrangements for the anchor cable bitter ends;

• The physical condition of ventilators, including the condition of securing arrangements of flanged connections on the vent standpipes.

Masters must ensure that whenever poor weather is expected the anchor cable spurling pipes are adequately sealed. There should be steel plates which fit securely around the cable above the spurling pipe, and these should be sealed with cement and a canvas cover secured over the whole to ensure that location and watertight integrity are maintained. The Chief Officer must ensure that such arrangements, or the equivalent, are both available and utilised.

The anchor cable bitter ends are often secured with pins within the foc’s’le space. These pins are provided with ‘O’ rings which require regular maintenance. Should the chain locker become water-full, then if these glands are not watertight water will leak into the foc’s’le space and may result in severe flooding.

The condition of foc’s’le head vents should be carefully checked, particularly those which are placed in exposed positions. Where internal corrosion is suspected with associated weakness then the most prudent course of action may be the use of protective covers.

Some vessels have the facility to remove ventilator cowls and blank them. It is for the master to decide whether to use this facility when bad weather is expected.

3.3 Heavy Weather Precautions

The overriding consideration is the state of the sea – both the wave height and the swell height;

wind speed is of a secondary consideration as far as the prevention of water ingress is concerned.

It follows that the interpretation of the term ‘heavy weather’ will be different for vessels of different size, and will also depend upon the state of loading. It is the responsibility of the Master to decide under what weather conditions these procedures need to be applied, and to what extent. The larger vessels in the fleet will obviously consider that these procedures will require implementing only in more severe conditions than the smaller vessels in the fleet. However, Masters should bear in mind that the onset of bad weather can happen extremely quickly and seas can build rapidly.

When heavy weather is expected the following procedure must be complied with to the extent deemed necessary:

• Crew members should be prohibited from proceeding to exposed areas;

• All watertight openings must be securely closed;

• All mooring ropes either stowed on drums or off the deck;

• Anchor securing arrangements and spurling pipe covers checked;

• Cranes and davits properly secured;

• Stores and equipment on deck, and in store rooms, the accommodation and the engine room properly secured;

• Additional securing fitted to equipment such as liferafts and lifeboats;

• Covers fitted to equipment which require it, such as exposed vents, winch controls, mooring wires on drums etc.;

• Removal of lifebuoys, or additional quick-release lashings fitted;

• Where necessary, the free surface effect in ballast and other tanks reduced to an acceptable level;

• Consideration given to reducing the amount of fuel in high wing tanks to avoid overflow during rolling;

• Freeing ports and scuppers checked as being free of obstructions;

• Sufficient bunkers aft available to avoid having to transfer during bad weather;

• Lifelines rigged as appropriate;

• Consideration given to menus which avoid the need to use the galley ranges.

3.4 Bilges and the Sounding of Compartments

There must be a daily routine for the checking of the foc’s’le space, chain locker, bow thruster compartment, cofferdams and holds, and any other space where unexpected water ingress might occur. Where bad weather prevents the checking of such spaces daily they should be checked as soon as possible after the weather moderates. In prolonged periods of bad weather consideration should be given to turning the vessel to allow access to spaces at least every two days. The record ECF7 - Non-Cargo Compartment Sounding must be maintained.

Regular testing of bilge alarms, where fitted, must be carried out. In addition, bilge alarms should be tested prior to the forecast onset of bad weather.

3.5 Vents and Sounding Pipes

3.5.1 Marking of Vents and Sounding Pipes

All vents and sounding pipes must be clearly marked to indicate which spaces they serve.

3.5.2 Maintenance of Vents and Sounding Pipes

Vents, whether on ballast, bunker, lubricating oil or other tanks, work on the principle that a float of some sort, when immersed in water, seals the aperture from which air normally enters or exits from the tank during filling and discharging. This prevents the ingress of water.

It is important that these vents are properly maintained; they must be regularly dismantled and the operation of the float or flap proved to be in good order.

Where flame screens are fitted, these must not be painted over or in any other way blocked. If they are, or if corrosion is evident, then they should be replaced.

3.6 Hatches and Watertight Doors

Ingress of water into compartments such as the foc’s’le space is often a very serious event and can have disastrous consequences. The cause is invariably a lack of attention to the watertight integrity of the hatches and doors.

3.6.1 Maintenance of Hatches and Watertight Doors

The packing and securing arrangements of all hatches and watertight doors must be maintained in good order at all times, including:

• The packing should be checked for condition;

• Dogs and securing arrangements must be well greased and free to move;

• Hinges must be greased and free to move;

• Hinges should be checked to ensure that they are free to move in the vertical – if not then no amount of tightening of the dogs will ensure water tightness.

With respect to packing, the following must be taken into account:

• The ends of packing must be cut at an angle of 45 degrees, and must not be square cut;

• The ends of the packing should be placed in the most sheltered position from the effects of waves;

• If packing is hard, cracked, deeply grooved or painted over, it must be replaced;

• The packing retaining track must be in good order. Corroded or wasted packing track should be repaired at the earliest opportunity.

The requirements for ensuring the watertight integrity of spurling pipes and anchor cable bitter ends are contained in the Mooring Procedures section.

3.7 Ventilators

Ventilators, particularly those on the foc’s’le, are prone to damage by wave action when heavy seas are shipped. The cause may be either poor design, poor protection from wave action, or corrosion. The result of a ventilator being damaged can be a rapid ingress of substantial volumes of water, with significant consequences.

3.7.1 Maintenance of Ventilators

The most significant issue with ventilators is that corrosion invariably commences from the inside is virtually undetectable unless the vent is removed from its base. However, in view of the significant amount of water ingress which can occur if a ventilator is damaged, it is prudent to check the condition of the internal parts of every ventilator exposed to heavy seas. This should be carried out on an annual basis.

Each ventilator will have a flap to allow the vent to closed in case of fire. The flap does not serve to provide any useful watertight protection. These flaps should be regularly maintained and kept free to operate easily by hand.

Some vessels have the facility to remove ventilator cowls and blank them. It is for the master to decide whether to use this facility when bad weather is expected.