Advance Marine Engineering

Qdestioas and Answers

Mum

bai

2.0'~ August,

2001

It .: 3 * --d

:r

Cf3,X evv-0lr-

3fety, on boaria a ship, is critically dependent on the s & e ~ , &ir values and the environmenr in which they live and work. Basic safety is inmporated in a ship though regufations and pr es.

As

&e

kGp7s s t r u a - e is exposed ro a highly corrosive environment, w d rriaiirte machinery is constantly subjected to very severe conditions, hazardous

coi:rlii;iufis can develop, misss the ship and its machinery is properiy maiutained. Mariners need to get a sufficient theoretical howledge, to srrpplemtnt their own practical experience.

3

is

nccessarj

far them to be pmperiy rrairied, both by lectures ashore, as we11 2s by self s k d y , w%k a; m.

> .

l o enabk stucle~ts to a d y , while at sea, the authors have prepared this text book in the form of a comprehensive s d of questions md answers, w5ic.h should supplement rfie riurnemrls standard textbooks already avai!abIe.

MI. Vikram Gokhaie 22;ld 34. Nmda are b ~ t h already well known in ihi: marine field. They a: Chief Engjneei-s, with e lot of practical experience, both as ship-board engineers, as welt as senior facu!ty in the LBS Coliege of Ar_lwam;ed Maritime Studies m d Research, one of the premier maritime imtitu.tions in India.

,l'%s book "Advanced Marine Engineehg Knowbrfedge - Volume 333 Qu&ions arsd A~swers" mitten by ?&. V i h m Gokhale and Mr. N. Nanda, iri1.s a co~omprehensive coverage of the t o p i ~ s required at- an advanced level for

. M F<fl Cefiifjatt% of Competency at Operation& and 7.iIanifgerneat Ievels.

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'L'hey have put in a lot of b a d work a n d 4 have mu& pleasure in payinrg rikj t i i i > ~ > t ~ io their dedication and sincere effortL All Mariners will find this

book of coisiderable v&re arid guidance I sincerely +sh them the best of st.~;i:i;ss i ;I this book.

Deputy Chief Surveyor with The Govt. of India, ?&inistry of Suriace Transport, Directorate General of Shipping.

arine Engineerjag Knowaedge - Volume

BX

Questions 2nd

Answers' cciiers *he following Functions / Subjects a: the Operatiand and

Functions :

1 . Marine hgincering ar Operariaad ! Managemen? level.

2. Bedrical, Efectronjc and Control Engineering at Operationai ! Managemerit kye!. 3. I./iainlenanse and Xepair at Operational i Management lwei.

4. Ccntroliing Operation cf the Ship and care for persons at Operational / Mmagement kvef.

Page Nos

5

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28.

29 - 60. 61

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95.

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Advanced &wine Engineering .Knowledge VoI. 111

Surveys, Reguiations a n d Environment Protection

Q.1. Describe the In-water survey, to classification requirements, of the

external underwarer structnre of a VLCC- k n s .

The Swvey planning should be worked otit well in advance of :he in-water stirvey, by the ship. in cooptratim 'virh Ihe classificaiion Society.

Preparation :-

Following documentation should be c o k c t e d and consulted wiih a view to seiectin~ areas and structural elements lo be examined.

Basic ship information; Documentation on board.

ivfzin structural plans including information of higher strengh steels Relevmr previous survey and inspeciion reports.

Infomratior: regarding corrosion protection level Location o f heated tanks

Informalion regarding relevant maintenance levels

To assist divers, coloar photographs should be provided. o f items s w h as ruddzr closing plates and wear-down gauge p!ugs.

The design of the ship %mt facilitate in-water inspec:ior, m d repair - e.g. Sea inlets must be capable of being blanked off and drained to biiges, shell gratings hinged, if practicable and the anodcs easily changed. The hull should be clean, to have meaningftil maintenance leve! during operation, besides h v i n s a heavy diity coating. This must be camerl out by approved diving company, in clear water, with good visibility.

~ ~ e r a t i b n :-

A self propelled, steerable survey vehicle fitted with a long range

T V

camera is used. To aid steering and to check

for

hull dis~oition, a d o s e up, high resvlution, TV coiour camera gives a true picture of the state of the coatings and we!d szams. In some cases, a 35 mm still camera is fitted. An ultrasonic probe :s provided to measure plate thicknesses and other equipment includes a depth meter and speed indicator. Power is supplied and information ieiayed by means of an unjbilical from the vehicle to ihe survey boat.

Survey Boat equipment:

Is usually housed in a console c0ntainingT.V. monitors, plate thickness print out. audio cassetze recorder, video recorder and play back unit, diver communication system, vehic!e control system and associated instrumentation.

The survey vehicle is taken to the staSing datum by a diver. With rhe aid o f one of the TV nionitors and using h e shell expansion plan as a map, the vehicle may

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Advancqd Marine Engineering Knowledye Vol. NI

be p,uided, from the control console, over the bottom and sides of the hull, by

foilowing weld runs and by reference to other features, such as inlets and tank

p l u g . Pictures and navigational information are relayed back and video

films

recorded,

along with plate thickness, giving the surveyor an integrated picture of

all the required and relevant information.

In addition to plate thickness, print-out

can be produced andlor an audio recording.

The vehicle will also provide pictures of such items as Stem frame, Rudder,

Fropcller, Bilse keels and hull ~penings.

A

diver may b s used. with a hanu held

camera. for closer inspection of these items and also for inspection of plating on

the tun? of the bilge.

It

should be ensured during this operation, that there is a

2

way co~mnunication

bctween diver a d

attending surveyor.

Q.2. Describe toe

h.;:l examination you would carry out on a ship in P r y

dock, making special r d e r e n c e to essential maintenance, that can be carried

out in

Dry

dock.

Preparation shouid be to a sufficiefit extent, as to facilitate an examination to

asccrt,~iir for an;r excessive corrosion, defomaticn, fractu~es,

damzges and other

s!ructucai deterioration.

Examination a n d testing

All sp-aces within the hull and superstructure are be examined.

In certain

circuiiistances, the internal examination of lubricating oil, fresh water, and oil fuel

tank:,

nlay

be waived.

in sp;ices iused for salt-water ballast, excluding double bottom tanks, where

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a protective coating is found in Poor condition,

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_{a protective coating is not renewed,}

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_{where a soft coating has t e e n zpplied or}

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_{where a protective coating was not applied, from the time of}

coiisil-iuction, Maintenance of class will be subject to the space in question being

irgte.rr~;il

ly examined and gauged, as necessary, at Annual surveys.

.

Double bottom compartments, peak tanks and all other tanks are to be tested

si.ifiicir,nt to give the maximum pressux that can be experienced in service.

T;trl!ts may be tested afloat, provided that their internal examination

is also carried

o~.it afloat. Where repairs are effected to the shell plating or bulkheads, any tanks,

in

way,

are to be tested to the Surveyor's satisfaction, on completion to these

reIjairs. 1r1 cases where the inner surface of the bottom plating is covered with

ccrrwi!, asphalt, or other composition, the removal of this covering may

be

c,.

,.iperr:jetl

;

with, provided that it is inspected, tested by beating or chipping, and

fijl.iii<i sound and adhering satisfactorily to the steel. All decks, casings and

si~pecs-structu~-es

are to be examined.

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t: ~ - f Advanced Marine Engineering Knowledge Vol. Ill ~.

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iVooCs

decks or sheathing are to be examined

-

if decay

o r

rsr

is

fosnd

or

ri;e

-

= f

~~. % . .

wood is excessiveiy worn, the wood is be renewed. %'her; a wood deck,

ialc 2 -

= ,

- . . .

stringen and lies, has worn by

15

WXI

or more, it is to b e

icncwed.

Alxen\ion is

~ ~

to

be given

10 the

condition of the plating under wood decks,

s5

eciqir;o

--:

'.

,

or

,~;:i:r

deck covering,

i f i t is

found that such coverings

are

broken, or are nct adhefizz

- < _-.

~

-.

closely to the plating, seciicns are to be remmed, as zecessary, to ascertain the

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3

%

condition of the plating.

!

Mechanically operated hatch covers

zrs

to

be resed, to confimi sarisfac:oT

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i

operation, including stowage, proper

51

of seakng

arrangements, operatjo1;al

=$

1

tesiing of power components, wire and chaias.

i

The anchors are to be examine&.

W.e%

&e chain cab!es are

rzngeii,

:hey are

[

to be examined, if any length of chain caSle is found io be r z h c e d in mean

i

diameter, at

its

most worn pa?, by i2

F/o

or more, from 2s nominal diamerer

-

i i

:

so, it

is

to be renewed. The Windlass is

to

be examined.

~~ ~

i

The chain cables are to ranged and examined on ail ships over five years

2 !

aid.

The

Surveyor

is

to be satisfied

-

that there are suitabi- mooring ropes .<,*he,;

these are Rule requirement.

!he hand parnps, s-oc?ions, warenight doors, air

\

and sounding pipes are to be examined.

Thickness

measurement

:

The Surveys may reqliire

to

measure the thickness of the material in ally

h

pxtion of the structure, where s i p s of wastage are evident or was:JSe is

x

normally fo~md. Any parts of the structure, which

are found

defective

or ~- - - ~- -

-

excessively reduced in

.

scantlings, are to be made good, by materiais of the

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:

_-

_-

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approved scantlings and quality.

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=

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i

Hail

Pain:iry (Essential rnaintenanee)

=

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?'he shell plating is examined

for

areas of paint work which must be repaired.

I

The whole surface of the shell

is cleaned and

prepared for re-coating with paint.

i

In some instances thz 'null mz;. be cleaned down to bar- metal and completely re-

:

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-

_-

_-

_-

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ccrated; in most situations, areas where paint is damaged and rus:ins has started.

the shell p!ate is cleaned dcwn to bare metal

and

rest of the areas are cleaned and

1

swfzce

prepared for re-coating. Surface preparation is done by m a n u ~ I wire

.. .~ ...

brushing and scraping with steel scrape~.s, power driven wire Snlshins, or high

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i

pressure water jetting

91

shot-blasting.

I

I

Compete surface is washed with fresh water and surface allowed to dry, before

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i

coinmencemeni of painting.

Any

scuppers, discharges or overflows, which may

direc: watiter on to t h e surface to be painted, should be biocked or diverted, before

f

paintjag is &+fled. The paint to be used should be compaiible with the previous

*

2

paint, un!ess the complete paint

is

being rcnewed.

i

f

Paint sprrcifiiations are to be piovided to the ~ & d

/

Painting sub-contractor. This

5

inciudps

nu;-.be;

o'cnzts,

f o r

touchup and complete coat, type of paint for each

coal,

t h i c l a e s s of t a r 5

coai for each section, i.e. bottom plating, boot top area

t

0

and toasid:s.

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Advanced Marine Eiigineering Knowhdge Vof. ill

1

%

& Q.3. As Chief Engineer briefly discuss the procedures you will follow :-

₈

When taking over as Cm of a large vessel.

"

₁

When taking ow; as C/E of a new vessel from a shipyard.

Ans.

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_I

Procedure : . Briefing at ofiice and Tzking-over on vessel j

A) Briefing at Office .<

I

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Superintendent I Tech. Manager will brief, as per ISM Cock . .

practices.

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I I T ~ ~ ~ M K ~

td;th

D

PA 9

Fill up appropriate check lists

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wherever required. ->

,k,hci~o-3

/ p o l

;ile- -

Read correspondence file. ' '

Find out I be aware of :

- Staius of surveys/certificates Conditions of class, if any

Take copirs and start planning for your stay on board vessel.

Read lzttcr prepared by outgoing Chief Engine?., giving all derails. nisciiss 1 Verify :

i;uel oil /diesel oil / lube oil soundings - c o n f i r m actual figures

match the logged figures, before acceping respmsibility from outgoing Chief Engineer.

* Voyage Requirements Bunkers expected

*

Consumptionpattern - a n y s p e c i a l i n s t r u c t i o n s . v b Oil record book.

9 Overdue Certificates I surveys, if any, and the company's

action plan in respect o f this.

,Maintenance status o f Main I auxiliay machinery Spares.

Stores

Vessel's sailing programme.

Random checks of alarms / instrumentation.< i' W S

)

Special tools on hoard

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,,,,,J;o~

LC ek

. i'ir & (.L:. h . c h e - +

% I e 3

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Advanced Marine Engineering Knowledge ibl. 111

Readiness for Port slate inspecri o n s - L S A / F F A . Check a]] files. f2i fFe-rent r h e c k f k t

- Drawings list.

- M a i n t e n a n c e canied out by ship's stafffworkshops.

~ . . ~ . .

. L i . .

- _{Meet 2/E, Elect~cal officer and other engineers/staff}

to corfinn any mcxe known or spzcific problems.

Siyrt and send a cornbind report, by incoming and outgoing Chief Engineers. to Head o f f i c e .

E) Taking w e r as Chief Engineer, for b r a d new vessel iron, tke Shipyard

The Objeciive shouid be to ensure th'dt

Efficiency of all systems is achieved b e f o r e a c c e p t a n c e . LiaLoil betwxn Vessei and shipyard is goad

P r o c e d u r e :

A ) Office : familiarize with the Vessel's contractual position

B)

At Sbipyard :

- Scrutinize progress reports Witness typical program

- Inspection afier t n a1 C ) Taking over (Final)

A ) O f f i c e

Famiharise with vessels contractuai position, viz. : Specifications and capacity.

Contract penalty clauses. Delivery date.

0 Speed and fuel consumption.

Status on class certificated. Guarantee period.

B) S h i p y a r d , .

Obtain working specifications covering changes, interpretations, additions and anicndments in respect o f :

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Advanced Marine Enginwring Knowledne Vol. 111

Progress reports.

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Random inspections of installed machinery. including switch gear.

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. . . Plant ~ balance ~ . ~ . - . hear balai&diagr&s., ...

:::,

~.

-1

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Crash stod ~ a l s . . ~.

. . . . . ~ . .

Inert gas t&t;&& &&& if applicable.' ' '

.. ~ . . .

{~djustment; for inte&ted bperations).

. ~ .~ steering Sals. ~- . . . :: %~,~ Biack-out test. . . .. Turning circle.

Communication and navigation equipment to be demonstrated. Boiler safety vaive test.

Hull vibration, including Accomodation and Machinery spaces, esp.ecialiy when ship is in tke light condition and

: - .:~. .,mo,,jng @tern; ..:... ; - ;.. :. .- . . . .

.. ~ . . . . . ~

.~ .

#achin&y Vibration, over-speed & power ranges.

~. ,:. :

:,..

-. ... .~ .

. . . _,_/:<_: ..

:

~ i r b o i k now? suri;ey of accommodat&n, Machinery spaces, Bridge *~t@ne control room. _.~~

:

. . . Ventilation flow rates.

. . . ~~. .

Potable water ~ t m e n i piant, galley and pantry equipment.

I n s ~ e c t i o n after trials :

Certain eq6ipment may have to bc opened for inspection, if not satisfied with its performance, ~. with respect to safety of the ship and personnel.

. . . . . . ._{. . .} . . . ~ ~ . ~.

' ' ~ x . h i n & o n of Main engine crankcase.

A d v a n c e d Marine Engineering Knowledge Voi. I / /

Electrical generator windings to be clean and h u l a t i o n readings recorded. Bilges to be cleaned and repainted. 1 3 1 ~ L c - i n c c e

io

c h e c k

/ c i ~ q

C ) Taking over (Final) Ccmplete the sea trial data. Spare gear, Outfit.

F!~elr: and Lbbiicar,ts. Cei;ificatcs of ciass

Clezn Eilgc's repaicr if necessary

The Master and Chief E ~ g i n e t r will sign the Foim of Acceptance, for the Vessel and the Owner's Representative wi!: accept responsibility of rhc ship, after satisfactory corny;!etlon F F ail the hzucial ziiangernents.

1

J'Q. 4. With rcspzc! to Kegulstions and Pc!lction contrul, expfain Reguiatiens with respect ti, c o ~ t r o l of discharge of oif f r o m machintry spaces o f at: ships This regulation controls dumping of -11 victuals, don?estic and op~r3riozai waste oenerated by a ship and her crFw 1 passengers. Imposes a complete Ban on

a

dumping of Plastics e.g. Synthetic ropes, nets and garbaye bags. Deals \villi pcllittion from (i) Oil (ii) Noxious Liquids (iii) Eazardoiis packaged snbsrances.(iv) Sewage; (v) Garbas-.

Eve13 stricter coti:rcls for 'Special Areas' e.g. Mediterranean, Baltic & Black Seas. Here dumping is completely banned - even food waste cannot be dumped within I 2 miles cf iand. Contracting parties to the com'ention are oblized to -provide facilities in ports for reception c f gaibage~

MARPOL, Anriex V

Garbage type Outside Speeial Areas In Special Areas

Piastlcs Disposal

prohibiied.

Floating dunnage, lining > 25 miles off Disposal

and packing materiak. shore. prohibited.

Paper, rags, glass, metal > 12 miles. Disposal

bottles. crockery and pi-ohibited.

sin~ilar refuse.

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A]! other garbage including > 3 miies. Disposal

paper, rags, glass prohibited.

Advanced Marine Engineering Knowledgb Vol. !I/

. _{Control of discharge of oil from h h c h i n e r y spaces o:a!l ships I}

Oil or oily mixture should nc? be discharged into the sea, unless the following conditions are satisfied :-

Ship is proceeding on a voyage, i.e. en-route and not at anchor. Not within a Special area

The ship is more than i2 miles from the ne-rest cczst. The oil content is less thar I5 p.p.m.

The required oil separation, filterkg and monitonnz ~quipmeq! is in use.

Food waste not

i comminuted or ground.

I

Oi: Discharge Monitoring and Control system-

System to come into operason when there is any discharge of effluent into the

sea and automatically stop discharge when the oil content exceeds the permirtcd 'zvei. System to provide a continuos record ofoil content of the effluent. record io

be identifiable as to time and date and retained for three years. Any failure of

~cjuipment to be noted in the Oil record book and all discharse stopped. Defect to

.he rectified before commencing next voyage.

Comminuted or ground garbage must b e able to pass through a screen

wi&

mesh size no larger than 25 mm. Garbage disposal regulations for special a r e s

J

shall take effect in accsrdance with regulation 5[4)(b) of Annex

V.

> 12 miles.

0.5. With respect to Sewage treatment, discuss the foHowing terms :

Biochemical Oxygen Demand.(B.O.D.), C d i f o r m count, Recommended lev& &purnping-oui solids a n d Bio-chemical digestion of seivage.

> 12 miles.

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Ans.

Rlochemical Oxygen Demand (B.O.D.)

It is used to give a measure of the strength of sewage, i t identifies the iioiogicai decomposable substances and is a test that depends on the activity of bacteria, which in the presence of oxygen feed on and consume organic matter.

Results o i i h e test are expressed as the amount of oxygen taken by a one illre sample (diluted with aerated water) when incubated at 200 for five days. Can be defined as the amount ofoxygen utlised by micro-organisms in the stabilisation of organic matter, B.O.D. of iaw sewage is 300 to 600 mgllitre. I.M.O. recommend a B.O.D. of 50 mdlitre aiter treatment.

-~~ p-p- -~ p~p - ~.

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Advanced Marine Engineering Knowledge Voi.

in

Coliform Count:-

Coliform organisms are recognised as the Indicator Organisms c f sewage pollution. The numbers presenl in sewage are large, each person contributinz between 125 billion, in winter 10 400 billion, in summer.

9.

Colifonn are present in the human inteGme and their presence in water taken as an indication of the pathogen count. The pathogen count are disease causing organisms, responsible for TyFhoid, Dysentery; Poliomyeiiris, Cholera LM.0. recommend a Coliform count of 250IlOO ml. of effluent after treatmert.

i

Recommenr!ed Iweis ofpumping-out soiids

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i

Solids:. Dizsolved - Solids which are in soluiion

r

Suspended - Solids physically suspended in sewage, that can be removed by

d

i laboratory filmtion. Arc relatively Ngh in organic matter.

j

_{. ~ . Settleable--Suspended solids that wili subside in quiescent liquid in a reasonabii}

f _{period (usua!ly taken} as one hour). f

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Suspended level ofraw sewage is 300 to 400 mg/litre. 1.M.O. recomrnen6s i!

I

level, after treatment, of 50 mglitre.

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.

c

Residua! Disinfectant -

E

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Afler treatment the residual disinfectant should be as low as poss~ble. 3

f Canadian iestfictior is between 0.5 and !.0 mgflilre. I.M.O. prefers thc use o i

1 L Ultra-Violet exposure to the method of Chlorinaiion.

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5

Biochemical digestion of sewage

5

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i^

6 _-/ Anaerobic Process :-

Anaerobic bacteria can only multiply in the absence of free oxygt.;~, as tliey

-

use chemically bound oxygen to survive: in the anaerobic process, the bacteria

break down the organic matter into, water, carbon dioxid; methane, hydrogen sulphide and ammonia.

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k

. .~. This pro'cess is also called 2utrefaction. Theses-produced

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are both noxious -

t

and toxic. The effluent produced is of poor quality and o&er by-producrs are

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5

-highveorrosive. . -

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I

?-

2

s

z.

Aerobic Proc255 :-

f

g

_{Aerobic bacteria require free oxygen to survive. In the aerobic process the}

- 3

3

bacteria Lie& down the organic matter safely. The Aerobic Process lias end

g

- s products of fizO i C 0 2 + Inen Residue + Energy to synthesis new bacteria.

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Advanced Marine Engineering Knowledge Vot. Ill

4 . 6 . With respect t o Sewage pumping-our systems, describe briefly she Chemical sewage system and the Vacuum sewage system.

Ans.

Chemical recirculation or the Zero discharge system

Sewage enters thz chemica! dosage tank, where it is mixed with chemicals,

WL

break dom the sewage and improve the.colour. It thcn passes through

a

conimirtulor (wbich is a grindzr o r macerdtoi) that curs :he sewage into small paticies) and e n t m a chemicai treatment tank, in which a further chemical treaiment is added, to sierilise and deodourise the!iquid.

/'

e.-?-je

A";..':

r

liu Uiru iS+4cge

+

i i + - ' ~ A ) I-,m .-

-wG

C ~ ~ = ~ ~

f

'

A circulating pump draws un-treated sewage from this tank and delivers back l o

riw

dosagr rank, where :he txeatment is agGn qplied. The sewage remains in ' this sction for about 5 minutes before passing to the senling tank. After senIing,

It162 cleiu liqilid is dram through a filter to the Sanitary Hydrophore, which

proviilcs the water supply to the toilet flushes. As the level in the settling rank rises,ihe sterile sludge may be removed to

a

Sewage holding rank or incinerated.

V ~ C I Y U I ~ sewage system.

This system is based on a vacuum created by an Eductor, which is used to pull in t!ie sewage into the sewage tank. Calculations are based on a daily fiow oS say, 10 liircs per person - using 1.2 litres of water per flushing operation. The %>%%ge t a n k capacity varies h - o m 2.5 - 10 m3. The holding tank is at atmdsFheric pressure.

,A pccssure switch maintains vacuum in the line, from the toilets by auto stnrlislop of centrifugal pumps. The water in the sewage tank is used as driving walv i'nr tile ediictor. Float switches may be used to control the discharge from the 1ioItli11,r: lank to the sewage treatment plant, while still maintaining the vacuum i n

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Advanced Mannne Engineering Knowledge Val. 111

J

/~.7. Gnumerate the preventive measures you wot>ld take to avoid po!lution of the env;ii-,rnent, with respect to Bunkering. What instructions wil! you

issue to the p c r s a n ~ e ! under you, in this respect.

Ans.

Preventive measures to avoid pollu!ion, while bunkering

The responsible officer should be famiiiar with ai: aspects of bunkering and the ship's bunkering system, and shouid personally supervise the operation. He must be in ciose contact ~ ? t h she shore 1 barge crew, especially with respect to stopping

of

bunkers, in case o f emergencies. Bunkering Operations :

The vessei shouid be securely moored.

-

_Ail valves should be checked and those not to be used, must be securely closed.

. Scuppers should be sealed.

. _{Oil absorben: materiai (sawdust, sand) should be readily available}

<

_{S@ IT E P )}

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_{Communication systems should be checked.}

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AdvancedMarine Engi~zenng Knowledge Vol Iff

Bunkering should commence a! the i ~ n i n l u r n pumping rate so [ h a ~ any problems can be detected early.

Frequent sounding 1 &ages should be Taken

'Paflicular care taken when 90% filling, capacity of tank is strained, aud bunkering stopped.

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O n completion special care taken when disconnecting hoses, removing drip trays.

Note : A 'persistent' oil is one that wiil not disperse easily e.g.

-

Heavy Fuel Oii, Diesci oil, Lubricating oil - and will i q c i r s a solvent or emulsifier, to d i s ~ e r s e in case ail oil spili occurs. Volatile oils, like pztrol are not persistent.

S e G m any ;ransfer of product is undertakeq the O S c e r must w n f i n the ibi!owing items, with the person in-charge of bargdterminal bunkering. Each will sign this f o m (sarnule). to acknowle6ge~

T

1 akirig 05/er wztch personnel, will slso revie-# the subject matter as be:ow-

Pinrpiiig Data

-

Q~murtity and typc of stock t o bet:msferred - initial trmsfer iatc

-

Maxiinurn transf, =r rare

-

bfaximum transfer pressure

. Anticipated stoppages

-

_{I'he method of communication bemeen b x g e a ~ d ve~sellteminal has been} established

-

_{(! ~%ill be understood that except for emergenci?~, a} 15 minute stand-by i h i : for shutting d c w d transfer is required.

. _{Arc hoses in good condition?}

;be connections between the barge and vessel/terminal properly secured 7

-

_:ire scupper plugs in place ?

-

_{A continuous deck watch will be kept by barge and vesseU terminal crews}

-

In the event of an oil spill, a clear mderstanding exists on steps to be

tnken (conaainment, clean up, reports, etc) _{s o P C P} All unused manifold connections arc blanked O K

Rotii prtics should cany out constant sun-eiilance o f adjacent waters to deted and pii:v:rtt ariy leakage / spillage of oil.

Advanced Marlne Engineering Knowiedgc Vol. !it

Q. 8. A s a Chief Engineer, what procedures will you foilow, ivhen accepti~);: bunkers, to ensure that tiley conform, With respect to the quantity a n d required fuel specification a n d how will you ensure this ?

Ans

When accepting bunkers from a barge or a teimiaal, the Chief Engineci s h o & ~ always check the local supplier's C o c u m ~ , to make certain that the bunker

conforms, in tenns of quailtity, as well as file1 specification, with what has been actuzllv ordere6.

:'I

The Chiei Engineer, or his nominee, sh9uld al..vayz check that the bunkers, to be received, do net contain hn unacceptabie ?-age of water contaniination -

the maximum ailowa'uIe being 0.05 'A for 63s oil, 0.25% ibr-Diesel oil and i % for

cavy

oil (of IS0 Cst). In case of distillates, this can be established by rncaiis of a simpie test, involving water finding ;;ask applied on sounding tape. The tape should be smeared with paste (usually y e e n in colour), which will turn pink, i i any water is detected. The water depth should then be read off a!id iis volumc and weight calculated From the barge or storage tank calibration tables.

1~1iis rn~tk~od can a l s ~ be x e d %i Fue: Oli

-

but 11s accuracy may not always

Sc 100% The o d y safe way of checking, in the case of Heavy fuel 011, is for a sample to be taken and the water coatert ttsted in a water tesz kit.

in additioii to checking the tightness of the hose couplings, it is important that

rhe pumping rate between bunker ba:&lcmiina! and receiving Vessel is asrceii by the barge Master and the vessei's Chief Engineer. Excess pressure can cause

the hoses.to burst with the harbour becoming polluted resulting in claims. fines

and even vessel's arrest. ,$

Ensuring correct Quantity/L)elivery:

Claims of insufficient volume delivery are the cause of many disputes between owners and bunker suppliers. It is the ship's s!affs responsibility to ensure t i n t they ectually receive the quantity ihat has been ordered. If not, then a lalcr of proicst mus! be niade 311t.

The Chief Engineer or his represenLalive must always check the supplier's bar$ terminal tank soundings, before and after pumping. Barge soundings should be checked by using sctinding tape, which are to be used with tank caiibration tables to verify the actual quZtity, both before and after pumping, ia ensure thai the correc: qilantity is received. Due care must be taken-to correct for tempeature variations, if my.

Note: In a quantity dispute, it is generally a mle with bunker suppliers, that ship's figures wi!l not be accepted. Measurements taken on tanks, barges and oil tmcks are accepted, as they are under the independent supervision of Csstoms. However,

a format letter.of protest must be made out, to keep the ship's staff in the clear. Flow melen should be checked, both before and afier bbunker delivery Mcters only rccard volume (no! weight) - either in 'US barrels' or 'Litres' - both of

Advanced Marine Engineering Knovrledge Vol. IN

wirkh c a n be convened into metric tons, by using the product's specific gravity and !lien adjuslins for lcmperature differences.

Tmt liils for checking fuel quality : Bunker quality on board can be checked wiih a fuel oil test kit. By carrying out a few simple tests on representative s:~mpi~?s, iiom the ship's bunker flange, and not the bunker barge o r shore tank, the C h k f Engineer can satisfy himself, that the prodact is indeed upto specification ant! compatible with existing~bunkers. Samples of the loaded product must he taken jointly.

'Thi: sample must be representative of the total delivery, and ideally taken by drill feed at t h e discharge side of thz manifold, during the course of the pumpin!: process. Samples should not be taken at the start or 3~ h e completion oC

bunkering, because then they will not be a re?resentative of the rota! t3nnage loaded. ALSO samples should pot be from just one t a k on the barge.

. . _{Sainpie bottles should be sealed, datzd andsigned hi - by boik the C h i d}

Tingineei- and the local supplier. Two identical samples should be taken. One silould :.hen be retained by the ship's staff, for about three months or at leas? until thc burtkeis loaded have been consr~mea without prohiem.

lit c;n;:: of any quaiiiy problem, a sealed sample must be sent by{ the Chief Lrigliieci asiinrc, so that a proper analysis can be carried out. In the event of :I

gcrwiiii: &icy problem insins, it

k

imperative that the supplier is advised as soot? as posslbi~. The supplier may decline to accept liability, i f this is not done witflin a specikd period. (The prribd for notification should he cie2ir:y stated I::

ihr: suppliefs terns and eocditions)~

lhm!ccrs are the rernsining products from varying world sources orcrude oil. and v w y i ~ ~ g methods 3f cracking, thus there is no 'standardised' heavy oil - each om: is corismng of different hydrocarbons from varying sources. Thc delivcrcd proiluck may conform to the specifications, but however when mixed in the lank with a pmdl.ict refined from a different crude oil source, incompatibility can occur. I hi: lr~ixed products will layer and could re;u!t in an ~un-pumpable s i u a g ~ anct wrisequent ?nor combustion in the main engine. Altemaiiveiy, the product could hecrime completely un-pumpable or unbumable.

. .. ~~. _{. . '1.0 ~t</oid rhese problems, bunkers should ideally be segregated, in srtparalc}

tanks, so iix>t no mixing occurs - although this is not always possible on smali ships.

Q.9. With respect to regulations, discuss briefly :

a) <:ontrot of discharge of oil from cargo tank areas of Oil tankers.

b) Con(!-01 of discharge with reference to Chemical Carriers. Ans.

/

Advanced Marrne Engineering Knowledge Vol. tll

-

-- Sea areas

C

i Wiihin a Special area I Outside a Special area Within 50 nautical miles from land. - More than 50 nautical miles from lrnd Discharge criteria i

No Discharge except clean segregated ballast

.-

No Discharge except cl&n segregated ballast

No Discharge except either : clean or segregated b;iliast; or when: tne tanker is en route; and the instantaneous m e of discharge of oi! doesnot exceed 30 litres per nautfcal mile. and

the total q-aiitity of 4 discharged does s o t exceed 1/30.000 ( f ~ r new - d e r s ) of the total quantity of cargo. which was camed on the previous voyage: and

the tanker has in oprrarion :

An oil discharge monitoring and coiiirol system and slop tank arrangements as required by Regulation 15 of Annex I of MARPOL 73/78.

'Clean ballast' is the ballast i~ a tank which has been so cleaned that the

. effluent from &ere does not create a visible sheen or the oil content exceed

!5

3pm . Regarding chemical carriers, Amex I1 of MARPOL 73/78 deals with poliution by noxioils liquid substances.

3-10 With respect to Oily water separators, justify the statenrent : Separation of oif a n d water depends upon the density difference behvcen oil and c*ater. Aiso comment on the use of z cna!escing device a n d heating coits.

Most designs of Oily water separators in use are of the gravity / coalescer type, i.e. rhe separation rakes place by gravity, and depends upon the density difference between oil and water. The coalescing device encourages the formation of large oil droplets from the dispersed pha$e.

i n .eneral. bilge water contzins a mixture of oil in water i.e. a small amount of oil in a large amount of water. The water is know? as the contini~ous phase and the oil is the dispersed phase. The oily water enters the separator and is slowcd down (ideally lo laminar flow). Thus the larger giobules oroil arc :illc.:~:c.d 10 rise due to the density difference.

Advanced Marine Engineering Knowledge Vol. NI

-i

'

P!ates cncouragc a laminar flow and act as coalescing suriaccs. Thc ratc

or

separa:ion depends upon the difference behveen the viscous drag at the oilfwater interface and the effect of gravity. As the size of the oil globules increases the viscou.; drag decreases and the gravity increases.

The fomiarion of larger gkbules is accelerated at the coalescing surfaces. Also as rhe rate of change in density, with respect to temperature, is geater for oil than

. - - twa!w, lire

----

rale oiseparation will increase with ternzerature. _{- -}

BgL2nlp3:

Shouid be matched to the application {must not exceed the intenzed capacil] ~ i ! h e separator).

Vane or screw type are the n o s t suitable pumps.

Provision f2r washirg out with sea water should be pl-ovidcd.

Heeiing Coils;

.-

@

Reciuce visco~ity fa: washins out.

Ilcdiice viscosiry o i the oil water - thus aiding sepaiation. ICcduce viscosity of oil -thus aiding pumpins.

lricrcase differential specific gravity.

'0.12 Oii poilution regulations require any transfer o r discharge o f o i l or oity mixiawes lo be recorded in :be

. . a. P o i i i ~ t i o n C o n t r o l record

b , Wsidge log

,>A:. Oii Record Book

4 . tMvsters log

e , None of above

Rrietly jristify your answer.

h s . ?'tic correct choice is the option c).

All ?egistered merchant vessels must eany an Oil Record Book.

. 8 . ,

1 ' 1 ~ s ii~r;!udes a11 Bilge transfer operations, Ballasting or cleaning of bunker fuel !ail!is and the discharge of dirty ballast or cleaning water, Disposal o f oil residue, i>ischaiy oveiboa~d of purihed bilge water from machinery spaces.

.,. i ankers have additional entries to record

-

Loading, transfer during voyage and rlis<;har~;c of ori carso. Ballasting and cleaning of cargo tanks and the discharge ofdirty bi~llast.

lf;iny vessc! fails to carry an approved Oil record book or to make proper entries,

(1.13. How is discharge of oil monitored. Describe the general principles o f measurement or the following:

a) Ballast Monitor b) Bilge Monitor c) Turbidity meters

d) Clean Oi! System

e ) infra Red Absorption

r7

riitra violet detector

g) Light Absorption & gas measurement. Ans.

The oil pollution reguiaticns p t h i f a t i o n s on the quantity o f oil discharged into the sea. There is 3 requirement to monitor the overboard discharge from-.

A

ranker bc:last line as i i discharges directly overboard.

A tanker ballas; discharge afier an oiiy-water separator. ( s ~ o ! = ' < G b d P ?

A bilge Sischai-ge from the mxhinery space. (i 5- p (J m )

~~~

The equipmen! mxst be suitable for the marine environmeat (Xithough rilierc are many laborztory me:hods, which.are accurate; not all can be used on hoard shipj. The equipment must be suitable for reading both high and low levels of contamination 2nd tc respond quickly to sudden changes iit Lhose levels. There shoul8 be no appreciable loss of accuracy, due to the presence o f san;, rust and other debris, and must operate satisfactorily, irrespective of the rypc of oil used. The equipment must be easy to operate and maintain. Its working should be unaffected by considerable periods ofidleness. It must be accurate to i !0% . Principles of Measurement :

i

.

Infra Red Absorption. 2. Ultra Violct Absorption.

3. Visible Light Absorption. 4. Visible Light Scattering.

5. Ultra Violet Fluorescence

R e first four are al; poor with respect to sensitivity and would usually be used only to detect an oil-water interfaces (in an ci!y water Separator). Infra Red ~ .

absorption is a useful method, as_most*bsorb in the 3.3 Prn waveleggth. The vari&ns, in absorption rates, between heavy oils through to the iighc diesels is approximately 10%.

Advanced Marine Engineering Knowledge V o l 111

However, watcr also has a strong absorption at the same wave length and this makes detectors complex. It would be useful if the oil was extracted from the watcr with a suitable sclvent, the solvent having no absorption of tke infra re2 w e d s n g t h . However this would not allow a speedy response.

U t r a vioiet absorption does not encounter the water absorption problem as i t uses a wavelength of 0.25 Fm. but the requirement, for the opto-electronics to detect sniali c!~anzcs in a high light level, limits the low range capability. Absorptisn devices using any wavelength, on a system whcie the oil is present in tihc fonn of particles, suffers from the effects of sand and rust, distoning the accuracy. This is significant a i d adds geatly to the prsblen of inaccuracies.

. . . .

Devices using v r s ~ b h t y light are usually cheaper, simpler and are nowspecific with rzspect to 31: types. However, they also detect, without distinguishing between, oil and non-oil particles of similar diameter. Of the two visible light teciiaiques, absorption and scattcikg, the most sensilive is light scattering. tlltra violet fluorescence suffers from a wide variation in respcnse !o different types o f oil.

Caliasi Monitor :

.

-

h

icprcsentative sa7iple n u s t be extracted. This is achieved by a strengthened intrusion pipe in the ballast line and :he sample is ?her? con-eyed to the nlonitoi oy

2 puinp. 'Yo ensure a representative sample is obtained 2nd to encoiiiaze sood

mixing, the sample point is usually ,in the middle of the ballast pipe, near !he discliarze pump. Care niust be taken to ensure the ballast line is a:ways Cull of sea water, so that no settling-out occurs. If the response time of the monitoring system is Ioii:> ~ n s i d e r a b i e pollution can occur b e f ~ r e the large discharge valves can be closed. Additionaily it is important, that the operation of the valves shouid not be iniriarcd by a false alarm, caused by a small spike of oil exceeding the alarm level.

Geimaily the response d t h e m c n i t ~ r is instantaneous and most of the system respoilsc delay is in the sam.pling pipe-work. To reduce the delay, short length of samplc pipe with a minimum number of bends, utilizing a fast sample veIocity are iidopted. This pipe- work ofien becomes clogged during periods of inactivity and, when restarted, erroneous readings are obtained as oil, deposited during periods oi'idieness, strips off the pipe-work. Most monitors depend on an optical teciu~iqi,!i: and this leads to problems with the sealing and cleainp of the optical witldows. h fast sample flow rate helps in keeping the windows clean.

'Clilgz i\;lonitor :

. . .. ~ . ,

I iru~ailation and operational problems with a biige monitor are less than tt~os;: hi. the ballast monitor. The bilge monitor must provide an alarm at IS ~ . P . H I . 7 ' t ~ alarm, being within the engine room, does not have the installation probletr~s

of

the ballast monitor, as very short sample pipes can be used.

Wi!ii the bilge system the type of oil czn vary from fuel oils to lubricating oils, ilr:m:c the monitor should not be specific to an oil type. Additionally the wir~dow !)roblen> assumes greater importance ar the system may well have to operate with llic machinery space unattended.

ie

g

~ . .

-

f Advznced Marine Engineering Kncwledge Vol. ;;I

a

E

.;j$

: Q Turbid@ Meter (Scatterqd Light Detector) :

:~E

- _{If an oiliwater mixture with a low oil content is heavily agitated, s o that the}

oi! droplets become v e y small; the water will turn 'milky' to varyjng degrees, depending on the amount of oil present; the actual colour of the oil droplets is of no importance. This method can be used for indicating the oil content, provided the conditions for homogenizing thz sample are well contro!led. If a light beam

2

projected through a test cell containing sample water with well-homogenized droplets, pan of rht lighi passing through the czll will be scatiered.

f i e

intensity of light picked up by a photocell at the end o f a straight path through the cell will be reduced, whereas the intensity of scattered light sensed Ey a photuceli mounitd at an ang!e to the original path will increase.

_R

_7-t

c F . ~ [

-

$ i + - ~ ~ i ~ +-

I me&w.i&- c e i l

J

Mearming reif with

rwo P.E.celis ;Measuring ci:.cuil

c ~ , , , , . ~ :

LX..~. &-- ! .. r.. ,.. :,,.>~-- ::.. '-

-".,

. , .

_-

sj > : ~ .- . kc&, ..'- . . ~ : . ,,' Tub

c

r

~

~

c

<.

'*'

,,l,-

Laser light nray be used to obtain a well defined Ik*t bean] and a selective light-scattering effect. This principle is used in the Ci: content meter, in which the light beam and the s i p p i c k e d up - by the photocelis are transmitted via optical fibres -- to the electronic measuring circuit in the engine room, through-ne

- mom bulkhead, where the penetration is quite small. The Indicator, Alarm and controi panel are in the Engine room. A similar instrument, operating with infra- light, is also inuse. Another Lnsmtment, based on theturbidity prixip!e, operates only on the direct transmitted light through the test cell, in which the heavily agitated water circulates. instrument of this type can measure oils ranging from heavy cmde oils to gasoline, but some changes in the calioration are required, to cover the extremes of the range. As the instrument measures the number of pmicles in the water, it is rather sensitive to other contaminants such as rust or air bubbles.

Advanced Marine Engineering Knowledge Val. ill

Infra-red absorption :

The absorption o f infra-red !ight by oil can also be m e ~ u r e d . As infra-red absorption by the background water is aiso high, am oil-kee reference water of relevant quality must be obtained at all iimes; this is done by purifying a small part of water in a micro-filter. T t e inka-red absorption by the oily water and by oil-free water can then Se measured. The difference is caused by absorprioii by the oi! and, the s i p a l can be calibrated in oil content.

T h e Ultra Violet Detector :

The Principle used here is that of Uiha Fluorescence. This is the phenomenon

. _{- of the emission of light from a molecule which has absorbed light. In the brief}

period, before the emission can occur, some energy is dispersed and the emitted light is of a longer wave-length :ha? thr absorbed light. For a given oil-in-water concentration, the instrument response depends on a) the particie size and b) the

florescent efficiency of the oil.

The effect of particle sizc is minimized by the sample conditioning unit which reduces the oil particles to a uniform size. The fluorescent efficiency of the oil is based on the phenomenon that - molecules of "unsaturated" hydrocarbons become excited, when illuminated with ultraviolet li@t of a certain wavelength.

They radiate light in the visible spectrum. Different oils contain different amounts of msaturated hydrocarbons, so that the instrument must bc calibrated each time, for the type of oil being monitored. The instrument is simple in dcsign, and has be& installed in tankers.

Advanced Marine Engineering Knowledge Yo/. NI

Q.14. Sketch and describe a Sludge Incinerator ? H o w is the waste disposa:

effected. Ans

An Incinerator is capable of dealing with waste oil, oil and water mixtures u p to 25% content, rags, waste and soiid matter from sewage plants, if required. The figurc below shows a small combined water tube iype boiler cum incinerator plant which gives a compact unit with good economy.

S i " d ~ r / , , i l I;*:::,$ ,c7m-

Spinning cup bu

Incinerator

Wasit: i oily-water mixtures, suitably homogenised, produce a well-dispersed emulsion. These are supplied to

a

rotsry cup burner. Solid waste f n m ?Ite galley and accommodation is collected in bags and placed in a chamber adjacent to thc main combustron chamber. There is a safety device, which prevents the doors being opened, if the burner is 'on'. Hydrocarbcn gases are formed, duz to the low air supply to this compartment, which pass throtigh a series c i s m a l l h ~ i e s in the furnace. Dry ash has to be removed pcriodicaliy through the ash pit door.

Solid matter from sewage systems is also incinerated in this unit by homogenizing it with the oily-water mixture, befjre supp-;;ring thc rotary cup bfirner. The incinerator is capable of burning liquid waste or wet g a r b q e . Combustion o i solid p a i c l e s requires a considerable dwell time and this is usually achieved by angling the burner to give a 'cyclone' effect.

One of the main problems is to dispose-off items like glass and metal containers, which tend to soften in the flame, but do not readily bum. It is necessary to prevent these agglomerating into a mass that is difficult to extract. For this reason many incinerators bum refuse on a grate. The burning process for liquid waste requires that there are no rapid changes in content. Hence it is necessary to ensure an efficient homogenising process in the sludge tank.

Cost 05 the incinerating process must be considered. Since incineration is iniriaied using diesel oil, lo sran with a stable flame, i t is using up fuel. In an effort io rccovcr t5is cost, combined boiler cum iccinerstor units are used, as shown abmve, which may not be economical on a cargo ship, with a small crew, but is a econnmica! unit on passenger ships, which incinerate a large quantity of garbage

~, daiiy.

Q.15. Discuss hriefly the methods used for the measoremeot of Noise levels

and t h e recommended limits for noise levels.

Sour~d is generated by vibration o f surfaces or by turbulence in air streams, sciiing-up rapid prssure variations in the surrounding air. The n o m a l human ear is sensitivz to frequexies between 20 Hz and Z0,OOO

Hz.

The human ear is pai-;iciiIarly sensitij~e to noise in the 1000 - 4000 Hz [ 1 - 4

kHz)

range, which is objeciionabie and m+y lead to hearins impaimcnt.

f?ieasilren,m; of Noise :

P-loisc is measxed in terms cf thc 'sound pressure level' excressed in decibeis WG), 01 k e 'A - weightzd sound level' dB(A).

Rwuoxriei~ded Noise Level timiis :

Unrnarinzd machinery spaces (UMS) 1 l o dR(A)

Con!inuousiy manned machinery spaces 90 dB(A)

Ensine control room ( E C X ) 75 dB(A)

Mess moms and public spaces in Accomrnodatio,l - 75 dB(A)

Day rooms, offices 65 dB(A)

Cabins and hospital . 60 dB(A)

?fk?hodo 02' controlling Noise exposure : S.?pi!a-:l?iou of Noise sources.

(i)

W t w e practicable, noisy machines should be sited in spaces, thar do not r q w c c continuous attendance.

(ii) Provision of suitable partitions, bulkheads to reduce the spread of noise. ?sovision oi'sound absorbing material in certain spaccs.

(i) 111llow and discharge ducts should be arranged, such rhrt !hey are remote Smru spixes frequented by personnel (such as Fan rooms) and be fitted witit i:fkc!ive silencers.

(ii) Siicncec; shooid be reg-zlarly inspected and cleaned, to ensure sr~fficient air iniakc i:; possibie, with theminimum of noise levcl.

Advanced Marine Engineering .Knowledge Vd. 111

Machinei-y Enclosul-es.

. (i) In continuously manned mschinery spaces, which contain machinery emitting noise above the prescribed leve!s and where i t is not practical to isolate this, consideration should be given to the fitting o f sound insulation enclosures (acoustic hoods).

Use of e a r protectors

Where noise ievels in any space are above the prescribed limits, signs should be posted, advisins the use of suitable ear prolective measures. Ear protectors shauld be provided for personnel entzncg such spaces, viz. duty engineers making r~urine inspections.

Manufacturers siiould supply i n f o r m a t h on expected noise lzvels and r e c o ~ m ~ e n d appropriate ins~allalion metho&; to reduce theK, as f2r as practicable.

Q.16. Discuss what precautionary practical measures wouid you fo!lo~v oil

baard vessel, as Chief Engineer, w i t h rzference to lke ccatrol ana

m;tnasemznt of the ship's Baffast water. Enumerate t h e basic safety

precautions to be taken, in your opinion. Ans.

Minimising iniake

-

~ of harmful axtttiatic

-

o z n i s m s , =hogens a n d sediments :

When loading ballast, every effort should be made io avoid the intake of potentially harmful aquatic organisms, patbogens and sediment that may contain such organisms. Avoid baliasting, ifpossible, in a r e s and situations such as:

-

in very shallow water;

ir, dadmess - when bottom-dweiiing or2amsns may rise up: where propellers may stir up sediment.

&move baflast sediment on a timely basis :

Where practicable, routine cleaning of the baI!asi iank to remove sediments should be canied out in mid-ocean, or under controlled arrangements in port or dry dock, in acwrdvlce vv3h the provisions o f the ship's ballast water management plan.

If it is necessary to ballast or discharge ballast water in the same port to facilitate safe cargo operations, care should be taken to avoid unnecessary dischharge ofballast water, that has been taken up in another port.

Ship's engaged in Ballast water exchange a t sea should be provided with

procedures, which account for the following, as applicable:

Avoidance of over and under pressurization of ballast tanks;

Free surface effects on stability and sloshing loads in tanks ihat may be slack at any one time,

~ d v a n ; e d ~ w i n e Engineerhg Knowledge Vol. I11

To take account of weather conditions;

W e a t h ~ r routing in areas seasonably effected by cyclones, typhoons, humkanes, or heavy icing conditions;

Maintenance of adequate 'intact stability' in accordance with an approved trim and stability bookiet;

Pemissibie seagoing strength Iimits of shear forces and bending moments in accordance with an approved loading manual;

Torsions! Forces, where relevant;

Minimum/maximurn forward and aft drailgk:~; Wave-induced hull vibration;

Documented records of ballasting andlor de-ballasting;

Contingency procedures for situations which may affect the ballast water exchange at sea, including deteriorating weather conditions. pump faliure, loss of power;

Time to complete the ballast water exchange or an appropriate sequence thereof, takine into account that the ballast water may represent 50% of the t ~ t a l cargc capacity for some ships; and

Monitoring and contro!iing the mount'of ballast water.

I f the 'flow-though' method is used, caution shoukl be exercised, since:

Air pipes are not designed for conrinuous ballast water o v d o w ; Pumping of at !cast three full volumes of the tank capacity could be needed to be effective, when tilting clean water from the bottom and overflowing. from the top; and certain watertight and weather-tight closures (e.g. manholes) which may bc opened during

ballast exchange should be re-sewred, Ballast water exchanges at sea should be avoided in freezing weather conditions;

However, when it is deemed absolutely necessary, par;icular attention should be paid to the hazards associated with the freezing of overboard discharge an-angements, air pipes, ballat system valves together with their means of contro!,

ar~d the accretion of ice on deck.

Some ships may need the fitting of a loading instrument t o perfom. calculations of shear forces and bending moments induced by water

- -,exchange at sea and to compare with the permissible strength limits.

An evaluation should be made of the safety margins for stabi!ity and strength contained in allowable seagoing conditions specified in the approved trim and stability booklet and the loading rnanual, relevant to individual types of ships and loading conditions. particular account should be taken o f Stability, which is to be maintained at all times, to values not less than those required by the Administration.

Fire

and

Ships Safety

Q.1. With r e f e r e n c e t o C o n t r o l s t a t i o n s a n d F i r e p a r t i e s , d i s c u s s t h e i m p o r t a n c e of: a) M u s t e r l i s t b) F i r e c o n t r o l PIan c ) Essentirrl R e q u i r e m e n t of F i r e P a r t i e s Ans.

The muster list shall be pemanentiy positioned and displayed throughout the vessel and shei! q e c i f y definite signais or, th: whistle o r siren, for calling the crews to their emergency stations. The muster list shall also specify the means of indicating when !he vessci is bc aSandoned.

The muster !is: shall show the duties assigned to c.ew m e m b e r s i n rcspec: of -

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a. :he d o s i n g of watertight dgors, fire cloijrs, side scuttles, valves a n d other ope~;in_gs in :he vessels superstructure.

b. The equipping o f the lifeboais and other lire saving s?pliances. C . The iacnchir.2 o f lifeboats and liferafts.

d. General preparations o f any other boats and life saving a~;.liances. e. The niuster o f passengers (if any).

f. The sxtinctiun o f fire. F i r e Controt Plan

For the extinction of fire, a -5re conlro! plan should be drawn u p and be p e r m m e n ~ l y on display, showing the following detaiis.

a. Sections o f the vesse! enciosed by Oje resisting bulkheads.

b. Section o f the vessel enclosed by f ~ e - r e t a r d i n g bulkheads.

C . T h e fire cor.lro1 plans should be annotated, showing the fire alarm call

points. sprinklers, fixed insiaiiations, poriabie extinguishers, equipment, breathing apparaius and fireman's outfits. At

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glance, the complete fire

a r r a n ~ e m e n t and distribution can be seen.

: @: Means of access to and escape from compartments and decks. e. ventitition systems, fan controls and dampers erc.

f Location o f the international ship to shore ccnnectidn(s)

g. Locations of all machinery stops, fuel oil remote shut o f f vaIvcs and e n ~ i n e room skylight closure points.

Fire Parties I Drills

The essential requirement o f a good fire drill is that it is made ? s realistic as possible and nevcr al!owed lo become monotonous o r routine. Fire drills shouid be held in rotation to include :-

a. All crew members.

C. All fire righting equipment to bcutilised.

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d. Fire drills to b e c a r r i e d b u t a t different times and, on occasions, the drill should be carried out without an advance warning.

Fire drills shousd be carried out in the following way :

i. One officer from each department, i.e. Engine and Dcck, should be put

n s Fire Drill Officer, whose duly i s 1s submit typical fire drill situations relevant to his department. These to include details of extent of fire, scurce of ignition, equipment to be used, personne: to be involved and a full de-brief peiiod afterwards, which is equally important to the learning process.

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1 1 . Fire drills should be conrlucted in different areas oF:he vessel, s o a s to

include accommoda:ion area, cergo, and machinery spaces. ...

i ~ i . Use blacked out Breathing appaiatus face =asks o r safety smoke generators lo give B. A. wearers the benefit of experiencing zero visibility, as worild be expected in rzal life sitcations.

. Fill up an old boiler suit v:ith rags, to simulate a 'body', for search an<: xescue Teams to get p:ac!ice, in evacuatins personnel.

Apart from the need to conduct fire drills invo!ving the entire crew. ik:e is a strong case ibr ifivoiving s p e c i a l i ~ e d fire parties, hand picked men, >wiio have a particuiar aptilude, skil: and knowledge for fire fighting s o a s to m g e n d c r team spirit, confidence and communications as on efficient ream. Iluring these drills, breathing apparatus should be - worn and coii~mnnications/!ine signals difigenily practiced, until the B. A. teams can iiiiiy understand and be understcod.

Fire drills should be varied every time and hypothetical fire situations weatcd to co.jer every possible contingency. Try t o visua!isc a g i - e n fire and adopt boundary cooling accordingly . All equipment should be brought to a

::\ate o f rcadiness, i.e. fire pumps started, fire mains charged, hoses run out in position and charged. It is very important for the p-rsonnel t o get t h e feel of

itre equipment during practice, rather ihan in action for the first time.

Before any fire drill is actually starled i t is mosr important that a roll call is taken and 211 persocnel accounted for. This is especially. significant when the case of an engine room fire, before the vessels ~SXST-W CO, fixed instal!ation can b e actuated into the space, the area must be fully evacuated.

Many such fires have, in the past, been allowed to grow in intensity because of the confusion and delay caused by a lack of positive knowledge regarding the whereabouts of all the staff.

The following ~ o i n t s a r e considered to be necessary to a good shipboard fire or-pnisation.

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. . The organisation should be simple to understand by all onboard.

11. It should be easily adaptable, to keep ilp-to-date.

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