preparation of holds

CHAPTER 5

PREPARATIOru OF HOLDSGeneral considerations, disposal of cargo residues, preparation for cleaning, washing, clear'ing blocked bilge suctiong drying, sweeping, preparation of bilges and testing of fittings, holdinipections, time required for hold preparation, final preparations, hold coatings, ballast holds

suctions, non-return valves and bilge lines. The holdsmust be swept very thoroughly and the cargo residuesmust be lifted out of them before the holds are washed.

An alternative arrangement, found in some bulkcarriers of all sizes, is the fitting of port and starboardbilge eductors in each hold. These eductors dischargedirectly overboard through discharges at deck level.There are no filters or non-return valves in the lines,which can discharge lumps of cargo the size of applesprovided that the diameter of the discharge line isiuffrcient. As a result, thorough sweeping and removalof residues is much less necessary.

From the foregoing it is obvious that, whenpreparing to clean holds it is necessary to know whichtlpe of water removal system is installed.

Nature of cargo residues: Soluble cargoes such assalt will normally present no problems for holdwashing, and sweepings of granular cargoes like olivinsand or concentrates can usually be washed awaywithout difficulry provided that the pressure of thewashing water is maintained at 7 kg/ crli.' (100 psi) orbetter, and that the holds are drained by a directoverboard discharge bilge eductor system rather thana bilge pump system. \Arhere cargoes come in largerlumps, like quartz, for example, it is particularlyimportant to ensure a complete discharge of thesweepings since remnants cannot be drained from theholds and will have to be lifted out by the crew.

Disposal of cargo residues andassociated waste

The Marpol regulations"3 and national and localregulations govern the disposal of cargo residues anddetermine whether thev are released at sea or landedin port. These matters are discttssed in Chapter 25,while in this chapter each of the alternativeorocedures is clescribed.-

Alternative methods of disposal: Most cargoresidues are washed from holds, the washings beingdischarged into the water alongside the ship. \A4renresidues cannot be washe&from holds they must belifted from the holds for later disposal. A geared bulkcarrier equipped with her own derricks or cranes willbe able to use them if necessary to lift sweepings fromthe holds, provided that the ship is steady enough topermit the use of the ship's gear. The sameionsiderations apply to a mobile crane, such as iscarried aboard some large bulk carriers. If theweather is rough or if the ship is gearless and has nomobile crane, it will be necessary to use a muckingwinch (described in Chapter 22, and sometimesknown as a sediment hoist) and davit fixed to thehatch coaming, or access or trimming hatch, to raisesweepings from the hold.

Use of mucking winch: A mucking winch and theseamen who use it can only handle small quantities ofsweepings-for example, a full bucket or 20 litre

Cleaning of holdsgeneralconsiderationsWHAT cleaning is needed?: When the discharge of ahold is completed, the chief mate wil l need to decidehorv, when and if the hold is to be cleaned. Holdsshould always be cleaned in preparation for the nextcargo except when the ship is engaged on a shuttleserr,ice carrying the same cargo. For example, on acoastal serl'ice carrying coal between two Danish portsthe charterers found it cheaper to send the ship fromthe discharge port without emploving trimmers toclischarge the final sweepings. Turnround time wasreduced by two hours and the cost of employingtrimmers was avoided.

Similarly, a ship engaged on time charter for thecarriage of iron ore mav not clean the holds betweencargoes, even if different srades are carried, thoughthe holds will be 'shovel cleaned' by shore labour inthe discharge port. \Arhen a ship is on vovage charter,the normal requirement is for the holds to be cleanedleady for any cargo, or for the particular cargointended next voyage.

\A'hen on time charter it is advisable to askcharterers what they require by way of hold cleaningsince charterers understandably object to paying theo\\.ners for a wash costing US$l,000+ per hold whenall they require is a sweep, which is often free.

Need for complete discharge: Cleaning the holdsrvill be much more difficult if quantities of cargosn.eepings have been left in the hold, particr.rlarlv ifthe cargo is not soluble in water, so the ship's officersn'ill do all that the1, can to compel or persr.rade thestevedores and trimmers to discharge all thesrveepings. If a bilge cover plate has been displacedand cargo has filled the bilge, the trimmers will beunwilling to remove it. If they cannot be induced todo so it will be worthwhile to send the crew to get allthe cargo out of the bilge before the finish ofdischarge, so that the contents of the bilge can bedischarged along with the rest of the cargo.

Stevedores are often willing, if asked, to return to ahold where discharge has been completed, to removesrveepings gathered by the crew. They may even beprepared to leave a grab resting in the hold for a whilefor sweepings to be shovelled into. On a gearlessbulker such help is very welcome.

System for removal of water from holds: Bulkcarriers are usually provicled with a bilge suctionsystem, which uses a pump or an eductor in theengineroom to extract water from the holds. Thewater is drawn through the bilge lines to theengineroom and discharged overboard. Such a bilgesvstem is usually operated with the same pump oreductor as is used from stripping ballast, a processdescribed in Chapter 7.

Such a system cannot be used to wash large particlesof cargo out of the holds as cargo residues will clog the

BULK CARRIER PRACTICE 69

drum-at a time. The container is filled in the holdand carried to a position below the mucking winchwhere it is hooked on and raised to deck level. It isswung clear of the hatch coaming and landed on deckwhere it is immediately tipped over the ship's side, oris emptied on deck for later disposal, depending uponthe nature of the sweepings and the location of theship. Sweepings can be tipped on deck in front of anopen hydrant, where the water from the hydrant canbe used to wash them overboard. Inexperienced crewmembers must be reminded to tip or wash thesweepings over the lee side!

Sweepings left on deck: If the sweepings have toremain on deck they present problems for the ship,since residues are liable to be blown about the ship bythe wind and they may stain the deck and the ship'sside. For this reason they should be retained in thehold until such time as it is possible to tip themoverboard. \Arhen this is not possible the sweepingsshould be stowed on deck in drums. On larger vesselswhere the quantities involved are too great for the useof drums, the sweepings are usually stowed betweenhatches and slightly dampened down to prevent themfrom being blown around the ship. Lifting ofsweepings from the hold is a labour-intensive andpotentially dirty process. It is always preferable for theship to dispose of residues by washing, and thismethod is adopted whenever possible.

Sweepings left in hold: If it is not possible toremove sweepings from the hold before arrival at theloading port because ofadverse weather or because ofthe weight and volume of the sweepings, they shouldbe piled in an accessible part of the hold, in drums orsacks if possible, ready for rapid removal upon arrival.In the rare cases when this is done, it will be necessaryto give owners or charterers maximum warning toensure that facilities are ready on arrival and offhiretime and costs are minimised.

Preparation for hold cleaningMany ships' officers have experienced the

embarrassment of finding cargo residues on thetanktop when the hold is opened in the loading port,although a thorough hold cleaning, and inspection,have previously been undertaken. This can occurwhen full astern is ordered in the approaches to theberth, and the resulting vibration shakes down tracesof old cargoes from inaccessible and undetectedsurfaces high under the deckhead.

To reduce this problem, some masters put theengine to full astern, allowing the ship to vibrate andshake down the residues at the start of the ballastpassage, before the holds have been cleaned. Evenwhen this is done, it is prudent to reinspect all theholds a few hours before the loading port is reached,so that any unexpected problems can be found andcorrected before loading is due to commence.

\A/hen discharging sticky cargoes such as grain, it isoften worthwhile to send crew members into the holdsto clean positions high under the deckhead duringinterruptions in discharging. Whilst standing on thecargo during early stages of the discharge they canreach places that later become inaccessible. Suchn'ork must always be carefully supervised to guaranteethe safen' of crew members.

70 THE NAUTICAL INSTITUTE

Washing holdsHandheld hoses: The normal method of cleaning

holds is by washing with water drawn from the sea.This involves hosing down every part of each holdwith a water jet whilst the water is drained from thehold by the eductors or bilge pumps, and dischargedoverboard. Three alternative methods of hosing downthe holds exist-using handheld hoses, warer cannon,or a permanent installation.

The hosing may be done by handheld hoseoperated by a team of cwo or three seamen. One willbe on deck to operate the control valve where thehose is connected to the deck service line (or firemain) and will oversee operations, whilst the otherswill drag the hose around the hold and direct the jetat each par t of the compartment in turn.

On larger vessels it is important to use at least twomen to handle the hose, since one will be unable tocontrol the hose at full pressure and will do a poorjob, either because the hose has been badly directedor because the pressure has been reduced. Aboard asmall ship with holds which are not particularly dirty,a handheld hose is often the quickest and bestmethod of completing the job. Handheld hoses areless satisfactory in larger ships-it is difficult to achievegood cleaning in the more remote parts of the holdand the method recuires a lot of time and labour.

Water cannon: An alternative to using a handheldhose is to have the hose led to a high-pressure sea-water cannon, such as the Combi-gun, on a tripodplaced in the hold. The Combi-gun uses compressedair from the ship's deck line to inject greater pressureinto water from the fire main. This svstem. more likelvto be used on larger bulk carrierr, p.ouid.t u -o..powerful jet of water than can be achieved with ahandheld hose and results in better cleaning of thehigh extremities of the holds. The system takes longerto move from place to place and requires as muchlabour as does the handheld hose.

The washing sequence adopted when washing withhandheld hoses or water cannon starts at the top ofthe hold and works towards the bottom. First, hatchcovers are washed on all sides, as far as possible.Compression bars and rubbers may need scrubbing toremove cargo which is sticking to them. Next, thecoamings, hold deckheads and hold sides are washed,papng particular attention to non-vertical surfacessuch as hopper angles, pipe guards and brackets.Finally, the deck is washed and the bilges are flushed.

Permanent installation: The third option forwashing the holds is to use a permanent washinginstallation with water guns installed under the deck-head in the hold. Aboard a mini-bulker the hold wouldbe equipped with one water gun at each end. Eachgun is wound down into the hold from a recess in thedeckhead. Water at high pressure is provided by directline from the engineroom. If the full washing prog-ramme is selected, the gun will then automaticallymove through a full washing sequence with the hosedirected first upwards to the deckhead, then more orless horizontally on to the bulkheads and finally down-wards towards the tanktop. Alternative washing prog-rammes can be selected. A bottom wash is a wash ofthe tanktop only. The programme is designed to washtowards the after end of the hold, where the bilge

sucticlns are located.Water must not be allowed to stand: All of the

foreeoing systems of washing depend r.rpon the flow of\\-ater to wash anv dirt and residues down thebr,rlkheads and across the tanktop to the bilgesuctions. If the washins is to be eff'ective, it ispreferable that the water is pumped or educted fromthe holds continuouslv and that no pool of standingrvarer is a l lowed to form on the tanktop. Whi lsr inballast the ship rvill normally have a good stern trim,causing the water to flow across the tanktop andthereby assisting the washing process. On some shipsthe washing is found to be most effective if the ship isIisted l" with ballast water; if one bilge suctionbecomes blocked, the ship can be quickly listed theother way, allowing the use of the other suction topump out the water. This will permit access to theblocked suct ion to c lear i t .

An exception to the foregoing occurs u'hen it isrlecessarv to wash holds in port because of lack oftime, bui the washings cannot be pumped overboarclin port. In these circumstances the washings can beleft in the hold to be pumped out when the vesselreaches the open sea. This procedure is often adoptedrvith the ballast hold and can be followed with anotherhold. orovided that it is safe to do so. It will be safeonlv piovided that the water in the hold remains at alow level, say, up to one metre, and pror,ided thatcalculations show that the ship's stability will remainadequate despite the reduction in metacentric height(GM) from the free surface of the water. The requiredcalculation is described in Appendix 8.1.

Washing stubborn dirt: \Vhen the holds are washed:rfter particularly dirty cargoes such as petrolelrm coke(petcoke;, the washing time wil l be extended in anattempt to achieve a satisfactory standard ofcleanliness. If it is found that greasy or discolourednatches remain thev will be hand scrubbed withdetergent by crew members, or washed with aportable high-pressure washins machine before theentire hold is again washed.

Certain exceptional cargo residues must not bervashed at all. It is reported, for example, that copperconcentrate, if u'ashed, wil l form a'concrete' layer onthe hold sides which can only be removed withabrasive discs on disc sander/grinders. This cargomust be cleaned by thorough blowing withc , rmpressed a i r and by sneep ing .

Fresh water rinse: \Arhen holds are washed with sea\vater, traces of salt remain on all the surfaces withinthe hold. This is unacceptable to some grain surveyorsand is liable to contaminate cargoes such as steelproducts and u'oodpulp. Salt traces will alsoencourage corrosion and are to be avoided ifoossible't" '. For these reasons holds should be rinsedn'ith fresh water after full washing. One method ofachieving a fresh water rinse is to load fresh water in asuitable ballast tank, such as the forepeak orafterpeak, and then to pump the fresh water throughthe deck service line for use in hosing dolr'n the holds.

\\4ren usins this method it is important that thecrew members operating the hose understand thatthey are using fresh water and not the sea water whichnormally runs throush their hoses. The water must beused efficiently and with care to provide a quick rinse

of each compartment if all holds are to be properlywashed with the available supply of water. On a handy-sized vessel such as th'e Regina Oklendorff, rvhere thefire pump has a capacity of 200 tonnes/hour, tlvo orthree minutes spent rinsing each hold with fresh waterwill use a total of 50 tonnes for the entire ship andshould remove most of the salt from the structure. Analternative method of fresh water rinsing is to use aportable high pressure washing machine. This will useless fresh water, but will take much longer.

Fresh water has a cost in most ports, so, if sufficientwater for hold rinsing cannot be generated aboardship. care should be taken to ensure that water forhold washing is obtained where it is cheap or free, thebest sources of supply being those few places wherethe ship floats in clean fresh water. \4rhen appropriatethe receipt for fresh water should be claused 'Hold

Washing-For Charterer's Account', as it is theaccepted practice in some trades for charterers to payfor fresh water washing when required fbr cargopurposes.

Fresh water washing of holds is recommended, butis done less often than should be the case because of theshort-term cost in labour and fresh water, and becausethe benefits of reduced corrosion and reduced cargocontamination are not immediately apparent.

Hand hosing of holds only in sheltered waters:Washing of the holds with handheld hoses is mosteasily achieved with the hatch covers open andnormalh' commences with a hosing down of the hatchcoaming top and the undersides and cross-joints ofthe open hatch covers. Such washing can only becarried out in sheltered waters or in calm seaconditions, since mechanical steel hatch covers arelikely to be damaged if opened or closed when theship is pitching or rolling.

Precautions when washing within port limits: In anincreasing number of ports""' hold washing r,vithin theport limits is prohibited since the port authorities donot want cargo residues discharged into their waters,regardless of lvhether or not the commodity inquestion is a harmful or offensive one. If there isdoubt as to whether hold washings can be discharsedin port, it is pnrdent to obtain written permission viathe agent. A spoken assurance from a stevedore is noguarantee that the ship will not be penalised later.

\Alhen hold rvashing is permitted at the berth it isusually necessary to discharge the washings onlv onthe offshore side of the ship to avoid flooding theje tg . I f ho l c l wash ing i s pe rm i t t ed u i t h i n t he po r t .arrangements must be made aboard ship to ensurethat discharge of washing water can be stoppedimmediately if a pilot boat or other craft has reason toapproach. This will ensure that accidental flooding ofa boat can be prevented.

Hand hosing of holds is difficult at sea: If holdsare to be rvashed at sea with handheld hoses, theprocess can be carried out most safely by leaving thehatch covers closed and passing the hose down theaccess hatch. Unfortunately this makes manipulationof the hose more difficr,rlt and provides poorer lighting.It also interferes with easy communication betweenthe members of the washing partl'. In these circum-stances there are strong reasons for opening thehatches 1 metre, if no more. Since the ship wil l be inballast with a large freeboard, there is nbrmalll' no


realistic danger of foundering as a result of openinghatches. The danger lies in the hatch covers sufferingdamage whilst they are unsecured, as a result of theship working in a seaway.

Hatch covers should never be opened at sea, exceptin calm conditions, and the hatches when open mustbe well secured. If conditions start to become roughwhilst hatches are open, the vessel must be hove-to toprovide a steady platform whilst the hatches areclosed.

Use of permanent installations at sea: Permanentwashing installations are designed to be used with thehatches closed. There is no problem in using themwhen the vessel is at sea.

Clearing of blocked bilge suctionsOne suction blocked: Prevention is better than

cure, and the blocking of bilges can be avoided bysweeping of holds and lifting of sweepings prior towashing and by the use of bilge baskets to catch largerlumps of cargo residue. Portable bilge baskets (whichcan be manufactured aboard if not provided-Fig. 5.1)are perforated steel boxes which are temporarilyplaced in the bilge wells to collect sweepings. Theymust be emptied regularly during hold washing. Thisis easily done during a manual wash and can preventproblems with blocked bilges and bilge lines.

which drives the eductor is forced through the bilgesuction into the hold.

If the tanktop becomes flooded as the result of asingle blocked suction, the hold can be pumped outby way of the other, with the ship given a small listtowards the clear suction. Since the blocked suctionwill be located within a bilge well, and since the bilgewell is likely to be from 1-2 metres in depth, it will benecessary to remove most of the water from the wellbefore the suction can be cleared. If the bilge well issmall in volume it is possible to bale it out withbuckets, but if the bilge well is a large one a portablesump pump, powered by compressed air or water athigh pressure, will have to be lowered into the holdand led to the blocked bilge where it will be used topump the water across to the clear bilge.

Next, it will probably be necessary to unbolt one ormore sections of the suction pipe to locate andremove the blockage, and make the suction ready foruse again.

Both suctions blocked: If both suctions are blockedand the water is lying in the hold to some depth, amore serious problem exists. Portable sump pumpsmay be able to remove the water but the requirementto pump the water the full height of the hold fordischarge on deck may mean that the process is a slowone, or that it proves to be impossible. One alternativein these circumstances is to open a manhole cover inthe tanktop at the forward end of the hold to allowthe water to drain into a double-bottom ballast tank.This can be done provided that the water at theforward end of the tanktop is not too deep to allowaccess to the manhole covel and provided that thewater drained into the double bottom will notcontaminate it.

Drying of holdsThe charterparry frequently requires holds to be

presented 'Clean and Dry', and the requirement for adry hold is not always easy to meet if the ballastpassage is short and the hold has just been washed, orif sweat is forming in the hold. Holds can be dried byventilating them when weather conditions arefavourable and this is a useful test of the cargoventilation fans. Some ships are provided withventilators for natural ventilation but not with cargoventilation fans, and ships on bad weather routes mayhave the ventilators unshipped and blanked off. Twosteps can still be taken. The crew can mop up all thepuddles which form in the depressions in the tanktopwhen a hold is washed. If the weather is dry thehatches can be opened when the ship reaches smoothwaters in the port approaches, and the flow of air overthe ship will help to dry the holds.

It is clear that the requirement for a dry hold isunnecessary when the intended cargo is stored in astockpile in the open air exposed to the weather, andshippers will normally be realistic and raise no objec-tions if the hold is damp on arrival. This is not a reasonto permit puddles of water in the hold and holdsshould not be presented for cargo in such a condition.

\A/hen commencing the loading of a cargo of grainin winter with holds which are sweating, it may bepossible to persuade the operator of the grain elevatorto blow some grain dust into the hold. This will stick

TANK TOP-----51- -r-t -=-U -,'' U-

BILGE 4.-- lglI|lLE BILGE -[

PORTABLE BILGE BASKET

co-ven q BASKET qilori' [- oo=.=cr.:]=,-crcf,REMOVED;RoM

-- BILGE wELL

HERE --

FIG 5.1

Hold washing should be monitored at all times todetect any build-up of water. If such a build-up occurs,washing operations should immediately be stoppedand the problem investigated. Directing a high-pressure hose into the bilge may be sufficient to clearthe suction. Alternatively, if it is a hold eductor suctionwhich is blocked, then 'flooding back' may be thequickest way to clear it. This is achieved by tempor-arily shutting the eductor discharge so that the water


BILGE COVER PLATE

DOUBLE BURLAPWRAPPING

L I N E N O RRAM-NEK

TAPE, OR CEMENT

EDGE OF PLATE PLATE EDGE OF PLATEIS FLUSH _ IS PROUD -SATISFACTORY WILL BE CAUGHT

Ftc S,2 BY BULLDOZER

to the moisture and will coat the hold, therebyreducing the contact befween grain and moisture.

Sweeping of holdsSweeping of holds when washing is not permitted:

There ire- at least three situations in which hold

as they can be landed or disposed of legally at sea. This

is work which the crew will be expected to do if timepermits, so the chief mate will make every effort toensure that the stevedores complete a good dischargeand leave the minimum of sweepings in the hold.Shore labour must be employed for cleaning if thereis insufficient time for the crew to complete the work

Sweeping of holds when washing is not necessary:Washing will probably not be required following a

clean cargo such as steel coils or steel slabs. It will be

sufficient to sweep up any debris and remove it fromthe hold.

Sweeping of holds in freezing conditions: Washingcannot be undertaken in freezing conditions. \A4renthe temperature is below freezing and the water isbrackish, as it is in the Baltic and approaches, washingrvater will freeze on bulkheads and coamings. In thesecircumstances holds can only be scraped and sweptclean, with all residues including ice having to belifted from the hold. If early warning is given, massivefan heaters can be hired in some Baltic ports to dryout holds if the ship arrives with a coating of ice in theholds to load a sensitive cargo such as chemicalf'ertilizer. The heaters are normally connected to a

rvhenever the stevedores will accept and discharge thesweepings before the vessel sails from the dischargeport- In addition the holds should be swept beforewashing, except when the residues are soluble orrvhen hold eductors which can remove the residuesare fitted.

Preparation of bilges and fittingsCleaning of bilges: When hold washing has been

completed, consideration must be given to cleaning ofthe bilges. Bilges are cleaned to ensure that theycontinue to function properly and do not becomeblocked with residues. In addition, they must bemeticulously cleaned with every trace of matterremoved and mopped dry, if foodstuffs such as grainor sugar are to be carried. Before carrying grain orother foodstuffs, the bilges should be sprayed with

insecticide and rinsed with disinfectant. \Alhenpresented for inspection they must be clean, dry andsweet smelling.

A bulk carrier bilge well normally consists of one or

two bays of double bottom space, anything from 2 m3

to 10 m'in volume. The space is usually cramped and

uncomfortable to work in. Any accumulation of

cargo should be removed and, when hold eductors

are fitted some of this can be achieved during the final

stages of manual hold washing by a man standing overthe bilge well and stirring the contents with a broom,so thai the maximum is drawn away through the

eductor.\Alhatever remains in the bilge must be dug out with

a hand shovel and lifted out of the hold by one of the

from entering the system and blocking the pump

strainers. The strum boxes must be taken apart,cleaned and refitted.

Flushing of sounding pipes and thermometerpipes: Hold bilge sounding pipes extend from theweather deck to the bilge wells in the hold, therenormally being one on each side, port and starboard.Hold bilge sounding pipes are essential for the

detection and measurement of any water in the holds,

blocked and unusable. This usually happens as a

result of cargo residues being left in the bilge well and

entering the bottom of the sounding pipe where, over

a period of time, they dry out and solidify.This problem can be prevented if the sounding

pipes are flushed out-i.e., hosed out with water fromdeck level after the hold has been washed and thebilge has been cleaned. This should be done asroutine, with the water being removed from the bilgewell by eductor or bilge pump. Some operators use an

air line instead of a hose to flush out sounding pipes,sealing the mouth of the pipe with rags wrappedaround the airline. The same alternatives are availablefor the flushing of hold thermometer pipes, whichmust also be kept clear.

Testing of bilge suctions: If the hold has beenwashed out and the washing water has been

discharged by eductors or hold bilge pumps, there willbe no need for further testing of the hold bilgesuctions. If the hold has only been swept or has notbeen cleaned at all, it is necessary to test the bilgesuctions to ensure that water can be pumped out ofthe hold during the voyage if that becomes necessary.The testing of the bilge suctions can be combined

rvith the flushing of the sounding pipes. Putting the

water down the sounding pipe into the bilge well

confirms that the pipe is clear, and pumping the waterout of the bilge well confirms that the bilge pump or

eductor is working satisfactorily.The correct working of the non-return valves fitted


in the hold bilge-to-engineroom lines (but not in thelines of hold bilge eductors which discharge directlyoverboard) can be tested by stopping the bilge pumpor bilge eductor in the engineroom, and allowingwater to flood back through the bilge line. If noneenters the hold bilge the non-return valve is workingcorectly. High level bilge alarms, when fitted, musr betested by raising the float and obtaining confirmation,usually by walkie-talkie radio, that the alarm hassounded.

Hold inspectionsThe chief mate is responsible for ensuring that the

holds are ready for cargo, and will normally inspectthe holds himself when preparations are reported tobe complete, if not before. If the crew members takean interest in their ship, it is quite likely that damageand defects noticed by crew members will already havebeen reported to him. The amount of supervision forthe whole process of cleaning will depend upon theexperience of the crew as well as their attitude.

During the ballast passage, loose scale may form ina cleaned hold, leakage into the hold from a ballasttank may occur or undetected cargo residues may fallfrom high in the hold. It is prudent to reinspect theholds at the end of a ballast passage, some hoursbefore the vessel reaches the loading berth, to allowtime for correction of any new problems which mayhave developed during the passage.

Cleanliness: The chief mate's first concern will befor hold cleanliness. If he has been instructed, or hasread, or knows that the next cargo requires aparticularly clean hold, he will inspect flat surfaceshigh in the hold, such as the flanges of beams visiblefrom the hold ladder, for signs of cargo residues whichmust be removed. \4lhen at tanktop level he will findwhether the bulkheads, hopper sides and tanktop areclean to the touch. He will look for residues beneathmanhole cover plates and behind pipe casings. Thebilge wells must be inspected. If the chief mate findsany fault he will know that a surveyor could use it as areason to reject the ship for a sensitive cargo, and hewill ensure that further washing or local cleaning iscarried out to remove the fault.

Rusg, steelwork within holds is not a reason forrejecting a ship in normal bulk trades, but loose (rust)scale is not acceptable as it is likely to mix with thecargo and contaminate it. Loose scale should beremoved by scraping and/or high pressure washing.

Insect infestation: Any trace of insect infestation inthe hold or in the bilges is unacceptable with anedible cargo. The owners should be consulted as soonas possible for advice about the best way of eliminatingthe insects without making the hold unusable for thenext cargo. Spraying with a suitable spray may besufficient, or the hold may have to be fumigated (seeChapter 21) .

Loose scale is a favourite hiding place for insects(otherwise known as bugs) , and the inspection forthem should be very thorough before perishablecargoes are carried. If detected by the inspectors,insect infestation can result in expense, delay andoffhire whilst the ship is fumigated. If they areundetected, there is a danger that the cargo will bedamaged and massive cargo claims will be


experienced.Leakage from ballast tanks or other sources: This is

probably the most favourable time to detect leakagefrom ballast tanks since such tanks will be full.Leakage from ballast tanks is a regular problem withmiddle-aged bulk carriers. Even if the leakage isminor it is still inconvenient. Ballast must bedischarged from the leaking tank before any cargo isloaded, to avoid wet damage to the cargo, and thismay be inconvenient. It will also be impossible topresent dry holds at the loading port, except bykeeping the ballast tank empty. If the leak is a majorone it will be easy to detect. It will cause an additionaldifficulty; as water drains from the leaking tank intothe hold the ship will develop a list.

\A/hen leaks are found, the chief mate will note theirposition with great care for subsequent repair and willarrange to pump out or drop out the ballast from theleaking tank as early as possible before arrival.

Hold damage: The hold should have been checkedfor damage during discharge and again uponcompletion, but when the hold is dirq' it is stillpossible for damage to be overlooked. The chief matewill inspect for damaged hold ladders. airpipes.thermometer pipes and sounding pipes and theircasings, and damaged piping for any hold smotheringsystem which is fitted. Local workers in many parts ofthe world insist that hold ladders, with platforms,handrails and protective hoops, are to be in perfectcondition. It is sensible to make sure that all is safe forthe ship's creq too, if accidents are to be avoided.

Damage to frames, brackets and plating should alsobe recorded so that new damage can be shown to bethe responsibility of the correct port and/or thecharterers. The chief mate will also satisfy himself thatno cover plates for manholes or gratings for bilgewells are missing.

Time required for hold preparationThe time required to clean a hold and prepare it

for cargo will depend upon the dirtiness of theprevious cargo, the volume of residues, the size of thehold, the resources available for cleaning, thestandard of cleanliness required, and the number andexperience of the seamen available. A reasonableestimate is that it will take three-four men one day toclean one hold of a handy-sized or Panamax bulkcarrier to normal cargo-ready standard from time offirst entering the hold. Cleaning to grain standard willtake longer.

Cleaning of a hold of a mini-bulker and preparingfor loading can normally be achieved by two or threemen, to a grain-ready standard, in four-five hours,whilst a routine hold wash and rinse of the bilge wellscan be completed in one-two hours. It is normally onlypossible to wash one hold at a time, though othertasks in an adjacent hold can be completed whilst thehold is being washed, if sufficient labour is available.

Final preparationsBurlapping of bilges: Bilge wells are usually

provided with cover plates consisting of gratings orrobust steel perforated plates set flush with thetanktop. (Fig. 5.2) They are designed flush with thetanktop to reduce the likelihood that they will be

from falling into the well.Smaller particles of cargo can still fall into the bilge

well so whenever dry bulk cargoes are to be carried it

Resealing of manhole covers: Double-bottom tanks

are located beneath the cargo holds and theynormally contain ballast water or fuel bunkers. The

access to each tank is by manholes set into the tanktopin the hold, though larger bulkers have additionalmanholes in the stool spaces. Each manhole is closedwith an oval steel lid fitted with gaskets and secured

Such a seal is achieved by using a gasket which is ingood condition, and by ensuring that the gasket andihe steel surfaces of manhole and manhole lid are allabsolutely clean, smooth and free of particles of rust

or cargo. \Alhen this has been ensured all the nutsmust be tightened hard. \4lhen closing of the manholelid has been completed the tank, if a ballast tank,should be pressed up (i.e., filled to overflowing) totest whether the closed manhole leaks.

It is not pmdent to press up a fuel tank, except bygravity, beiause the consequences of an overflowivould be so disastrous, so it may not be possible toDressure test the manhole lid of a fuel tank. For thatieason it is all the more important to ensure that theIid is fitted carefully and expertly if there is reason toopen it. Fortunately, reasons for opening fuel tanksaie much more rare than are those for opening ballasttanks.

\Alhen a manhole lid is in place, a portable steelcover plate, flush with the tanktop, is normallyprovided to protect the recess. If the cover plate is in

place it should be unshipped and any residues found

beneath it should be removed. Grain has been seensprouting from beneath these plates! During dischargeii is easy for the cover plates to become dislodged andlost. If thev are not fitted the manhole and its nuts andstuds are in clanger of being damaged. One method forprotecting them if the cover plate is missing is to cleanthe recess thoroughlv, spread old cloth over the nuts,

and then fill the recess with cement, smoothed off flush

with the tanktop. The purpose of the cloth is to preventthe cement from setting hard onto the nuts. Cementmixed to a strength of three parts sand to one partcement is suitable. When the manhole cover has next

to be opened, the cement can be removed with a

power cirisel or with a cold chisel and mallet.- Isolation of electric circuits: If the intended cargo

can burn or gives off gas which might explode, then

any electric Circuits such as hold lighting or forced

ventilation circuits which pass into or through the

Hold coatingsLimewashing: The shippers of most cargoes will be

unconcerned about the condition of the coatings of

the hold surfaces, provided that those surfaces areclean and free from loose rust, but for some cargoesrust can be a problem. One such cargo is salt used for

the preserving of fish; rust on the surfaces in the hold

will discolour the salt with which it comes into contact.If this is a possibility it will be necessary to limewashthe hold-to coat the bulkheads and the tanktop withlime-to prevent the salt from coming in contact withthe rusty surfaces. Sulphur is another cargo for whichthe holds have to be limewashed.

Limewash is made by mixing one part by weightof slaked lime (hydrated calcium hydroxide-CA(OH)r) with three parts fresh water' This job can

be done in the hold, the product being mixed in a

200litre drum. The limewash can be applied to thebulkheads with the hose of a portable sump pump,the pump being used to draw the wash out of thedrum. It will be necessary to limewash the bulkheadsto whatever height the cargo is expected to reach in

the holds, but should not be necessary to limewashthe deckhead. The aim must be to cover bulkheadsand tanktop with a good, thick even coat of limewash.

receivers and authorities in importing countries are

becoming increasingly determined to ensure thatfoodstuffi are not contaminated with any harmfulsubstance.

When foodstuffs are to be loaded and when a holdhas been recently painted, the authorities in somecountries insist on seeing evidence that the coating willnot harm foodstuffs. The paint compliance certihcatedescribed and illustrated in Chapter 14 is an exampleof the sort of evidence that may be required.

If the ship possesses no certificate for the paint andthere is doubt about the wisdom of painting, ownersshould be consulted. If they wish the ship to proceedwith hold painting they can, if necessarli consultcharterers and paint manufacturers.

Ballast holdsBallast holds can be used either to hold ballast or to

carry cargo. \Alhen cargo is to be carried it is essentialthat the proper steps are taken to ensure that ballastwater cannol be admitted to the hold by accident.


This is usually achieved by bolting a warertightcoverplate over the ballast suction in the hold and thismay be reinforced in the engineroom by fitting ablank, padlocking a valve or posting a notice. Blanksor cover plates which were fitted to the bilge and COrsmothering lines must be removed, so

-that these

systems can operate whilst cargo is being carried.These processes may have to be done, hurriedly, in

the loading port since the hold may have been usedfor ballast during the previous ballast voyage.

There is likely to be a conflict of interests betweenthe requirements for cargo and ballast, particularlywhen low density cargoes are carried, filling all cargospaces including the ballast hold. At such times it maybe difficult to find time and opportunity ro clean rheballast hold at the start of the ballast voyage, beforethe hold is ballasted. \Alhere possible the hold shouldbe washed or, failing that, swept. If a hold is ballastedwithout removal of sweepings as a result of pressure oftime, problems with blocked suctions will almostcertainly be met at the time of deballasting, when thehold may be urgently required, for loadin$.

Before ballasting it is, of course, essential to removeany blanks or coverplates which have been fitted toballast suctions within the hold and to seal the CO,lines.The bilge suctions must also be sealed to preventballast from leaking through the bilge system. Aboardsome ships, the same coverplate is used for the bilgeand the ballast suctions and must be unshipped fromone position and bolted in place in the alternativeposition.

Because of the time pressure which often existswhen ballast holds have to be cleaned and ballasted, itis useful to consider the priorities:. Before a ballast hold is ballasted the ballast line must be

unsealed and the bilge line and COz injection must besealed.

o Any sweepings or rubbish which could block the ballastsuction must be removed from the hold.

o If time permits and the next cargo will or may require ahigh standard of cleanliness, the hold should bemeticulously cleaned.

o If there is insufficient time to clean the hold thoroughlyor if the ballast water is dirty, there may be anopportuniq' to deballast the hold and clean it during thevoyage, refilling with clean sea water thereafter ifnecessary.

o If there is no opportunity to clean the hold at sea and aclean hold is required quickly in the loading port, thecrew can usually commence hosing down the open holdfrom deck level whilst the ballast is still discharging andcan enter the hold to continue washing down when thewater level reaches 30-40 cm over the tanktop.

Sources93. Marpol 73/78. Consolidated Edition, 1991. IMO.

150. Bulk Carriers: Cnidance and Information to Shipouners andOpnators. International Association of ClassificationSocieties. April 1992.

153. Baldwin, K. G. 'Hold Washing and Pollution'.Seaways, Jluly 1992.


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CfrECIgJST-Items for attention when ptepating holds fot car$o! Encourage stevedores to discharge cargo sweepings as far as possible.

! Have crew or stevedores sweep down deckheads and bulkheads as discharge proceeds-forexample, with €Fain cargoes.

tr If cargo has fiIIed a bilge have crew clean it before completion of discharge, so contents can bedischarged.

n Sweep holds before washing to remove bulky cargo residues, if required.

n Holds wiII not be washed if:Same cargo is to be camied again and charterers want no cleaning.Clean cargo like steel coils has been carried.Freezing conditions do not, permit washing.Vessel will remain j.n areas where discharge of washings is not allowed.

tr Decide if full wash or bottom wash is requlred, and if washlng is to be done by automated washingor by handtreld hose.

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Decide if washing is to be done at berth, withln port limits or outside limits, takin$ accountany restrictions on discharge of cargo residues and anticipated weather and sea state.

Obtain written permission from port, authority to discharge hold washings if intend to washpoft.

Wash holds:Wash hatch covers, top, bottom and sides.Scrub hatch cover compression bars & rubbers if necessary to remove cargo traces.Wash hatch coamings.Wash hold deckheads.Wash hold sides, paying particular attention to hopper angles, pipe €luards, brackets and othernon-vertical surfaces.

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. Scnrb locally and/or rewash to remove stubborn dirt.

. Wash deck, scrape up loose rust scale.

. Flush bilges.Rinse holds with fresh water when possible to reduce comosion and to prepare for cargoes whichcarrnot contact salt.Dry holds by ventilating, by openlng holds and/or by mopping up puddles, as necessary.

Sweep holds instead of washing when washing is not necessary.

Scrape and sweep holds and lift residues from hold when washing is not possible.

Clean and disinfect bilge wells.

Flush sounding pipes and thermometer pipes.

Test bilge suctions if not already used for washing.

Test bilge non-return valves, when fitted.

Test bilge high level alarms, when fitted.

Inspect holds for cleanliness, lnsect, infestation, Ieakage and damage. Remedy defects wherenecessary.Wrap bilge cover plates with burlap a,:rd seal with tape or cement.

Reseal any manhole covers which have been opened or disturbed.

Isolate hold lighting and lighting in compartments connected to the holds, when this precautionis required for intended cargo.Limewash bulkheads and tanktop if required for next, cargo.

If holds are painted, or touched up, before a cargo of foodstuffs is carried, ensure that a paintcompliance certificate can be produced for the paint used'

n In ballast holds, close and secure cover plates for ballast suctions, and open bil$e suctions andCOe i4jection lines.

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preparation of holds

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