Owners’ guide to CommonStructural Rules for Oil tankers

DNV Maritime

Information from the Leading Tanker Class Society

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DNV

25.1%

Others

74.9%

Tankers of 400 grt and above

Source: LR Fairplay and DNV databases

Estimated Market Share for Oil Tankers in

operation based upon GT as of 2006.04.01

DNV

26.1%

Others

73.9%

Estimated Market Share for Oil Tankers – orderbook

accumulated based upon GT as of 2006.05.01

DNV offers state-of-the-art competence and services for oil tankers

DNV has over the years accumulated unique oil tanker competence. On this basis we have also developed a wide

range of additional class notations to suit owners’ different needs for safe and reliable ship operations.

Our specialities are covering ordinary tankers of all sizes, harsh climate shuttle tankers and winterized tankers

specialized for cold climate operations.

Within all these segments DNV is market leader with highest market shares.

Now DNV is prepared to take this further, by offering our dedicated services to the tanker industry based on

the new Common Structural Rules (CSR), supported by updated and preferred software tools. The Nauticus Hull

software made by DNV Software provides unique support for CSR, combined with a highly efficient environment

for ship design. Its capabilities range from simplified rule-check and scantling calculations to advanced tools for

extended calculation procedures, including wave load and finite element structural analysis.

DNV Software is the commercial software house of DNV serving more than 3,000 customers in the marine,

offshore and process industries. DNV Software is a market leader in software development for design, strength

assessment, risk and information management.

We will be pleased to discuss new projects and share our experience with designers, yards and owners thereby

contributing to a successful end result.

For continuously updated information on the new Common Structural Rules, please consult:

www.dnv.com/maritime and www.dnv.com/software

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The IACS CSR for Oil tankersThe IACS Common Structural Rules (CSR) entered in to force 1st of April 2006.The new standard applies to all double hull oil tankers equal to or above 150meters in length.

DNV has expanded its activity world-wide to assistclients in implementing the CSR. An extensive train-ing program has been implemented for all approvalunits enabling our staff to be well prepared to provideefficient and local support to the industry.

We are also very pleased to introduce this practicalguide to the new Rules. The guide is primarily writtenfor use by shipowners and shipmanaging companies,with main focus on practical implications, and less onthe detailed technical scope of the Rules.

We hope this may prove a useful tool in your imple-mentation of CSR. We are looking forward to workingactively with you and being your preferred partner fornew oil tankers constructed/designed to the new CSRstandard!

Tor E. Svensen, COO DNV Maritime

The Common Structural Rules (CSR) arethe result of the combined knowledge,experience and latest technical expertiseof the world’s ten leading classificationsocieties, and they embody the very latestin practical experience and state-of-the-arttechnological knowledge.

Implementation of the new Rules The new Rules are applied by all the IACSmember societies, for double-hull oiltankers with lengths equal to or greaterthan 150m contracted for constructionafter 1 April 2006. Double-hull tankerscontracted for the carriage of oil and/oroil products are also defined as double-hull oil tankers in this respect. Chemicalcarriers designed to carry oil productsmust consequently also comply with theCSR.

The CSR cover the ship hull only. Fortankers below below 150 m and for mat-ters such as machinery, electrical andautomation systems, etc. the existing classRules still apply.

DNV-classed double-hull oil tankersbuilt to the Common Structural Rules will

be given the class notation @1A1 Tanker forOil CSR, with the additional CSR notationreplacing the existing NAUTICUS

(Newbuilding). Other notations will not beaffected, and hence additional notations

such as PLUS-2 and CSA-2, which includeextended calculation procedures andscope for fatigue analysis, will still be avail-able.

The existing NAUTICUS (Newbuilding)

notation still applies to oil carriers outsidethe CSR scope, such as Oil carriers below150 meters and chemical carriers withoutcertificate for oil carriers, as well as othervessels like container ships, LNG carriersand FPSOs.

Main characteristics of CSR The CSR were developed as a fine balancebetween new requirements, methods, cal-culation tools and existing empiricalrequirements developed and tested overseveral decades. The result is Rules updat-ed in accordance with new technology andknowledge, but at the same time incorpo-rating the experience gained through theoperation and survey of existing vessels inservice. The new key features of the CSRare:n transparency in development and

application.n new load model for strenght calculation.n net thickness approach.n coating.n enhanced fatigue standard.n buckling and hull girder ultimate limit

state assessment.

Transparency in the Rules is providedthrough clear objectives, clarification ofthe scope of the Rules, the Rules’ designbasis and, consequently, the Rules’ rangeof applicability and limitations.

The new load formulations which areapplied consistently throughout the Rulesfor prescriptive requirements, finite ele-ment analyses and fatigue have been devel-oped using 3D hydrodynamic analyses vali-dated through model tests.

A net thickness philosophy has been adopt-ed for the new Rules, providing a directlink between the thickness used forstrength calculations during the designstage and the minimum steel thicknessaccepted during the ship’s operational life.The strength calculations performed dur-ing the design stage are based on netscantlings. Newbuilding gross scantlingrequirements are calculated by the addi-tion of an allowance for the expectedwastage during the design life of the vesselto the required net scantlings determinedin accordance with the Rule requirements.

The corrosion margins specified in theCSR for different structural elementsreflect the different rates at which the dif-ferent areas of the ship corrode, sincelocal areas corrode at rates that can differwidely from the average corrosion rate ofthe whole ship. This is therefore a more

The development of the new RulesThe development of the new Rules for Oil tankers was initiated early 2002 withthe objective of developing common Rules to prevent possible competition betweenClassification Societies on the minimum safety standards. Added to this was the callfrom industry bodies for robust ships and the IMO goal-based standard. Valuable inputwas given by the industry during extensive hearing periods, leading to refinements ofthe Rules and ultimately producing the Rules as they have now been published.

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realistic approach, which more correctlyallocates steel within the overall structureto those areas where it is most needed.Even if the overall scantlings are somewhatincreased, it is important to note that insome areas the corrosion margins may beslightly lower than according to the previ-ous practice.

Another new and important feature inthe CSR is the coating performance standard.The IMO is going to amend SOLAS Reg.II – 1/3-2 and introduce a ‘Performance

Standard for Protective Coatings for Ballast

Tanks and Void Spaces’. Although theamended SOLAS II-1/3-2 will come intoforce earliest by July 2008, this perform-ance standard will be applicable for CSRvessels contracted on or after the adoption

date of the revised SOLAS II-1/3-2The attending surveyor of the Society

will not verify the application of the coat-ings, but will review the reports of the coat-ing inspectors to verify that the specifiedshipyard coating procedures have been fol-lowed.

A review of damage records for existingdouble-hull tankers shows that althoughthe absolute number of incidents is notsevere, the portion of the damage that isrelated to fractures is significant. A studycarried out shows that approximately 70per cent of all damages recorded are relat-

ed to fractures. This input has been usedas the basis for the Rule development andis reflected in the final Rules through theincreased design fatigue standard of 25 years

North Atlantic (up from 20 years worldwidefor DNV Rules), increased scope for finemesh finite elements and requirements forspecific design details in critical areas.

Closed form empirical buckling codeshave traditionally been used in class Rules.With the new CSR, a more sophisticatedbuckling code has been added for use instrength assessment by finite elementanalysis. The new buckling procedure includespressure effects and also takes into accountinteraction between buckling modes andthe buckling strength of the plate and stiff-ener and thus gives a more correct repre-sentation of the buckling capacity.

The new rules adopt a direct calculationmethod and include a direct criterion forultimate strength. This entails looking at thestrength of the hull girder for yielding,buckling and progressive collapse modes,effectively considering what it would takefor the hull to catastrophically fracture.

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Corrosion additionincluding owners extra

Required net thickness

New building In service

Wastage allowance

2.5 years diminution

Renewal thickness

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What DNVcan offer toowners andyardsDNV’s goal is to serve the industry in the implem-entation process of CSR. We aim to do so withhigh competence in all our approval centres andthrough increased service level towards yards andowners.

DNV has been very active during the development of the CSR for Oiltankers, and has delivered software to support these Rules for a long timealready. We have continuously scaled up our activity world-wide to assistclients in implementing the CSR for Oil tankers. An extensive training pro-gram has been implemented for all approval units, enabling our staff to bewell prepared to provide efficient and local support to the industry.

DNV can offer dedicated presentations of the Rules to owners and yards.Information about the consequences compared to present DNV Rules is avail-able. DNV has also developed detailed training courses which include all thetechnical aspects of the new Rules and the background for the same. Thistraining can be tailor made based on clients wishes.

We have skilled and competent approval staff around the world prepared tosupport the designers in developing their new designs, optimized accordingto the new common procedures.

>>

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Example illustrationustration from Hull Inspection Manual.

Hull Inspection Manuals for Oil tankersDNV has long experience in developing tailormade“Hull Inspection

Manuals for Oil tankers”. Such manuals are developed in closecooperation with the owner’s organisation, ensuring that theowner’s quality standard, maintenance strategies, key proceduresand experience are well reflected. Similarly, the involvement ofDNV hull experts ensures that our accumulated vessel and shiptype knowledge is incorporated. In the end, the owner will havea set of company- and ship-specific manuals that enable bettercontrol of the ships’ hull condition and thereby also the operatingrisks, maintenance costs and income.

The inspection manual provides clear guidance on how to carryout hull structure inspections and helps your technical personnelto focus on critical inspection areas, evaluate findings, and reportconsistently on the hull’s condition all through:n Detecting deficiencies at an early stage.n Being able to document the ship condition.n Maintaining a uniform standard across the fleet.n Reducing off-hire.

New Nauticus software with unique support for CSRThe new rule requirements for Oil tankers introduce a radicalshift towards more computerisation of the rule formulations andstructural assessment. Hence, good software support is critical forany Class to provide timely and rational support to ship-owners aswell as designers and shipbuilders. As a response to this, DNV’swell established Nauticus Hull® program has undergone a majorupgrade to provide efficient support for the new Rules.

Nauticus Hull is a powerful software package for the design andstrength assessment of ship structures. It provides a highly efficientenvironment for ship design, with capabilities ranging from simpli-fied rule-check and scantling calculations to advanced tools forextended calculation procedures, including wave load and finiteelement structural analysis.

In January 2006, DNV was the first company to launch completesoftware support for CSR for Oil tankers. During April 2006, DNVagain made a new release of its Nauticus Hull software, this timesupporting CSR both for Oil tankers and Bulk carriers, thus againbeing first, this time with software support for the new rules forboth ship types.

The software has been developed in close cooperation withmajor shipyards in Korea and Japan to ensure it supports thedesign process in a most efficient way. Therefore, the software hasbeen developed not only focusing on cutting modelling and inputtime, but rather cutting the total design and approval time.Especially, new tools have been developed to make Finite ElementAnalysis more efficient through automated post-processing andcode-checking, as well as generation of loads, net scantlings andboundary conditions. Also, a standardised report format has beendeveloped to ensure easy comparison between Prescriptive Rulesand direct strength assessment by FEA.

In the latest version, Nauticus Hull has also got radicallyimproved efficiency for generating local fine mesh FE models.

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Local fine mesh model of bracket toe for detailed stress assessment in

Nauticus Hull.

Cargo tanks FE model for strength assessment in Nauticus Hull.

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DNV welcomes the fact that the newCommon Structural Rules have beendeveloped using a consistent engineeringapproach that applies advanced analyticaland numerical methods based on engi-neering first principles to establish therequirements. This is in line with how theDNV Rules have been formulated for longtime already. However, similar to the DNVRules, also for CSR empirical and pre-scriptive requirements based on practicalshipbuilding considerations has beenincluded where appropriate.

In short, CSR may be summarized to yieldthe following characteristics:n Rules covering structural requirement

for Bulk Carriers and Tankers. n A Rule set utilising state of the art com-

putational methods for more extensivedirect strength calculations (FiniteElement Analysis).

n Vessels built to CSR shall have overallsafety of the hull structure equivalent toor better than that currently achievedby any current rules by any Class society,as illustrated in the figure below:

The reason for introducing CSR may besummarized as follows:n To obtain improved control over the

minimum safety level during the opera-tion phase.

n To eliminate competition between classsocieties with respect to structuralrequirements and standards.

n To employ the combined experienceand recourses of all IACS societies todevelop a single standard, or set ofRules.

n To ensure that a vessel meeting this newstandard will be recognised by theindustry as being at least as safe androbust as would have been required byany of the existing Rules.

What is CSR and why CSR?Many of the existing rules of IACS Class societies are largely prescriptiveand a result of an evolution from purely empirical requirements to acombination of empirically and theoretically derived requirements thatcompensate for the limitations of solely experience based rules.

IACS CSR

Individual society Rules

Requirements

Safe

ty l

evel

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In summary, the new rules offer severalobvious benefits for the shipping industry:n The new Rules allow shipbuilders and

designers to work with one common setof Rules, instead of one set from eachclass society. All IACS societies will coop-erate to maintain a single Rule set.

n More transparent technical backgroundof the Rules.

n The intention of the new Rules is toencourage the design and constructionof robust oil tankers and bulk carriers toeliminate competition on scantlings.

n Common Structural Rules compliantships will be designed to rigorous analyt-ical criteria.

n Extensive prescriptive requirementshave been put into effect with respect tothe application of the new CommonStructural Rules and the manner inwhich the central Finite Element analy-sis is undertaken so that consistency inapplication and common scantlingsresult.

n Stringent and clarified requirements tocritical areas.

n The minimum fatigue design life hasbeen upgraded from the 20 year world-wide trading to 25 year North Atlanticwave environment.

n The Rules include design standards forthe net scantlings of a vessel meaningthat the renewal thicknesses for the inservice time is checked and known atthe newbuilding stage.

n The corrosion additions that have beenestablished take into account the loca-tion and the environment to which thestructural member’s surface is subjected.

Benefits of CSR The new Common Structural Rules represent a significant step forwardin the establishment of technical standards that will result in a newgeneration of robust, safe ships.

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Impact of new Rules on actual designs

and the design processThe IACS Common Structural Rules forOil tankers will provide benefits to theshipyards in terms of the number of Rulesets and software packages they need tobecome familiar with. Whereas the exist-ing regime provides ten sets of Rules, thenew regime will provide only one.Another effect of common Rules is thatthe chance of the Classification Societiesbeing played off against each other in a

process that leads to unsafe scantling opti-misation, will also be avoided.

The application of the CSR to existingdesigns shows that there will be changes.They will influence steel weights anddesign details. Compared to current DNVdesigns, typical increases are in the rangeof 3–5 per cent and occasionally evensomewhat higher. This will reduce thecargo-carrying capacity for the samedraught. For oil tankers, however, the free-board can be reduced and the cargo-carry-

ing capacity maintained as long as applica-ble stability requirements are compliedwith.

The change in steel weight and scant-lings depend on the size of the vessel, typeof profiles used and degree of high tensilematerial. In general, the majority of thechanges are seen in the cargo tank regionand, to some degree, the forward regionof the vessel. For the cargo hold region,the new Rules are seen to give a slightincrease in hull girder sectional modulus

Practical consequences of CSRThe IACS Common Structural Rules for Oil tankers will providebenefits to the shipyards a well as to the shipowners. The new Ruleswill result in more robust ships, with an increase in steel weight.

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– Robust web frames.

– Robust lomgitudinals.

– Specific requirements to end connection areas.

– Attention to web thickness.

– Re-arranged stiffening.

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New definition of loads, attention to:

– Web frames – thickness.

– Breast hooks.

Continuous ground bar.

Stringer heels

– Normally require back brackets.Flange terminations

– Nice tapering and not too steep angle.

– Stringer toe most critical.

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Corrosion margins for Oil tankers according to CSR.

– mainly through increased deck longitudi-nals, increased transverse bulkhead plating,side shell plating, bottom plating andwebframe plating due to buckling, and sideand bottom longitudinals due to fatigue.

It is further seen that, although high ten-sile material may be used, this material can-not be fully utilised in areas dominated bydynamic stresses due to the higher fatiguestandard. This is particularly so for NV36steel. A typical example is the deck area,where the dynamic loads account for twothirds of the total loading and, consequent-ly, the fatigue requirement limits the allow-able stress level.

The figures indicate some critical areaswith stringent requirements in the newCommon Structural Rules.

Impact of new Rules on Ships in ServiceThe CSR will result in more robust ships.When properly operated and maintained,the through-life repair and maintenancecosts should be reduced and safety marginsincreased. The most significant impact ofthe Rules from an operational point ofview is that the wastage allowance will bethe same regardless of which classificationsociety has classed the vessel, and will beavailable upon delivery of the vessel. Withthe new net thickness philosophy, theowner can even determine the allowanceprior to contracting the vessel and henceuse this to determine if additional owner’sextras are to be added. As all the calcula-tions performed during the Newbuildingassessment are on the net scantling, no fur-ther calculations are required to be per-

formed in service to determine the allow-able wastage.

It may be worth noting that many char-terers of oil tankers today require CAP 2rating as a minimum in connection withvetting. This is a higher standard than the“pre-CSR” acceptable class minimum stan-dard. According to the new CSR, tankerswill satisfy CAP 2 throughout their lifetimeas long as they satisfy the new CSR mini-mum.

The CSR also include additional Rule-required loading conditions to ensure acertain degree of operational flexibilityregardless of the owner’s specifications.The key items in this respect are additionalballast conditions, Rule hull girder bend-ing moments, Rule hull girder shear forcesand Rule cargo density.

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Change in local design

– Welding details and size.

– Attention to plating thickness.

Tripping bracket connections to trv. bhd. vertical stiffeners and

curved large flanges.

Buttress toe connection to inner bottom.

Transverse bulkhead stiffener toe connections to inner bottom.

– Soft toe type

– Limit in allowable hull girder stress - i.e.

NV36 not fully utilized due to fatigue life.

Assessment for fatigue aft of the collision bulkhead, but forward of

bulkhead is not covered.– Robust bottom longitudinals.

– Robust inner bottom longitudinals.

– Brackets at transverse bhds.

Clarifcation of the new Rule text and

DNV’s interpretation of the practical

consequences of the new Rules.

1. Will ship designed to the new rules be heavier

than the existing DNV designs?

One of the objectives with the new rules isthat they shall be at least as safe androbust as the existing vessels. It is intro-duced new hull girder ultimate limit statecriteria, a new net scantlings approachand in addition higher fatigue design life(25 years in North Atlantic operation).Based on this we expect a 3–5 % increasein steel weight. The change in steel weightand scantlings will, however, depend onthe size of the vessel, type of profiles usedand degree of high tensile material.

2. How is coating treated in the new rules?

Although the amended SOLAS II-1/3-2not will come into force by earliest July2008, this performance standard will beapplicable for CSR vessels contracted forconstruction on or after the adoption dateof the revised SOLAS II-1/3-2.

3. Will vessels complying with DNV

Nauticus(Newbuilding) meet the criteria of

the CSR?

No. For the Nauticus(Newbuilding)design parameter is 20 years world-widewhile 25 years North Atlantic is applied inthe CSR. In addition, different yieldingand buckling criteria is applied in CSR.

4. Will it be possible to modify an existing DNV

Nauticus(Newbuilding) approved vessel to

comply with the new CSR criteria?

Yes, but such modification would mostlikely enforce changes to the existingscantlings.

Changes in the approval process in

particular when the new common rules

are implemented.

1. Will approval procedures and site procedures

be unified or harmonised with the new rules?

No, the approval process and site proce-dure will not be further harmonised thanin the existing regime.

2. What measures are taken to ensure consistent

interpretation of the rules amongst the IACS

societies?

Two Project Teams have been establishedin IACS, consisting of two members fromthe permanent secretariat and 4 technicalexperts. These project teams will answerquestions and conduct the technicalassessment of potential inconsistent inter-pretations, which may eventually draw uprecommended Rule changes for approvalby the IACS Hull Panel.

3. Will DNV do approval of a vessel if she is

already approved according to CSR by another

IACS society?

As the design is already reviewed andapproved by an IACS member, no signifi-

cant difference in scantlings is expected.However, in order to verify such expecta-tion, DNV will carry out full planapproval. If discrepancies are revealed thiswill be addressed in the appropriate IACSforum.

General discussion related to the new

Common Structural Rules.

1. Why change a system that has been in place

for more than 100 years?

Traditional prescriptive Rules were basedon empirical experience. They tended tofavour the side of caution and no explicitconsistent safety goals for the rules werestated. Irrespective of this they workedwell for many, many years. With the emer-gence of advanced structural and hydrody-namics computational methods, designersbecame able to improve designs signifi-cantly over the years while more preciselymeeting the rule requirements. In this waydesigners have been able to optimise shipdesigns with respect to construction andoperation.

In March 2001 ABS, DNV and LR jointlyannounced that they would work to estab-lish common criteria for ship structuraldesign, including hydrodynamic loads andcorrosion margins for standard ship types,beginning with tankers. The IACS JointTanker Project (JTP) and the newCommon Structural Rules for tankers arethe culmination of that project.

The IACS Joint Bulk Carrier Project

Frequently asked questions/industry concerns

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The questions and answers you find below areprovided with the purpose to clarify issues relatedto the implementation of the new Rules.

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(JBP) is a comparable development, fordouble and single side skin bulk carriers,undertaken by BV, CCS, KR, NK, GL, RSand RINA. Following initial developmentand harmonization of these two “pilotprojects”, IACS Council adopted theresulting Rules as IACS Common Rulesfor tankers and bulk carriers.

2. Are the tanker and bulk carrier rules based

on the same technical approaches and criteria?

The two projects started at differentpoints and have followed different pathsbut IACS has recognized that the two proj-ects must deliver a harmonized approachto the fundamental assumptions of hulldesign, particularly since the approachwill also provide the foundation for possi-ble future projects to establish commonstructural rules for other ships types.

Three class societies – ABS, DNV andLR – jointly worked to develop the newtanker rules. The other seven IACS mem-ber societies jointly worked to develop thenew bulk carrier rules.

The two projects have progressed inparallel in order to proceed as quickly aspossible. In the same manner that currentclass rules may take different philosophi-cal and engineering approaches to theestablishment of Rule requirements, thenew Common Structural Rules for tankersdiffer in some respects in their technicalapproach to those that have been devel-oped for bulk carriers.

Both approaches are technically sound.Neither is considered technically superiorto the other. Each will result in commonscantling requirements for a given design.Both are expected to result in vessels thatare at least as robust as those currentlyapproved to existing Rules. And thedegree of transparency regarding thetechnical justifications for the Rules ismore open and complete than at any timein the past.

The IACS members have recognizedthat for clarity and simplicity, the harmo-nization of the different technical app-roaches taken by the Common Structural

Rules for tankers and those for bulk carri-ers is ultimately desirable.

A long term plan has been adopted tooversee this transition. The key element ofthis project is that a vessel built to thefuture harmonized rule sets will be direct-ly comparable to a tanker or bulk carrierbuilt to the first iteration of the CommonStructural Rules that entered into forceon 1st of April 2006, as amended in theinterim to reflect experience.

3. Will the text of the Rules be the same for all

societies and therefore will the result, i.e. the

scantlings, be the same?

The new Rules have been developed toachieve the stated objective of eliminatingthe competitive element from the establish-ment of structural standards by producingcommon scantling requirements, regard-less of which IACS member society is select-ed to class the vessel. The text adopted intothe individual Rules of each society is iden-tical and future updates will also result inidentical amendments to that text.

4. Are the new Rules based on those of any one

society?

The development of the CommonStructural Rules drew on the collectiveexperience of the societies engaged in therespective tanker and bulk carrier projectteams, supplemented in inter-project dis-cussions and development with all IACSmember societies. The new Rules are notdirectly based on the Rules of any onesociety. They are reflective of the com-bined knowledge of all the memberswhich have contributed to their develop-ment. The Common Structural Rules dif-fer significantly from existing Rules.Therefore, making direct comparisons onan item specific basis is difficult and likelyto give rise to misunderstandings or misin-terpretations.

5. How to handle a contract signed prior to 1st

of April 2006 where construction will not

commence until 2007?

Ships or series of ships signed for construc-

tion prior to 1st of April 2006 is not sub-ject to CSR even if the construction is tak-ing place later than 1st of April 2006. Suchships will be subject to current DNV Rules.

6. A ship building contract signed prior to 1st

of April 2006 includes options for additional

ships. To which rules should the optional ships

be constructed?

Options included in contracts signedprior to 1st of April 2006 are not subjectto CSR if the option is exercised within ayear of the initial contract signing.

7. A ship building contract signed before 1st of

April 2006 is amended. To which Rules should

the additional ships be constructed?

Amendments are subject to the Rules inforce at the date of signing the amend-ment. If the amendment is signed on orafter 1st of April 2006, the ships are sub-ject to CSR.

8. How will the new common Rules be

maintained in the future so that they take

account of in-service experience and new

technologies?

Amendments is subject to the Rules in thesame way that existing Rules are updated,expanded or otherwise modified to reflecta deeper understanding of technical issuesand the proven results of applied researchand analysis, so too will the CommonStructural Rules be amended in future sothat they will embody the technically vali-dated knowledge that becomes available.

Relevant issues related to in-serviceexperience with the new Rules will also beshared within IACS, which has establishedan internal mechanism for the evaluationof relevant data. Two additional staff posi-tions have been created within IACS tocoordinate this process and technical pan-els of experts for the tanker and bulk car-rier rules respectively have been estab-lished. It is these panels that will conductthe technical assessment of the data anddraw up the recommended Rule changesfor approval by the IACS Hull Panel.

9. Is it likely that IACS will introduce common

survey Rules?

IACS is currently developing new UnifiedRequirements for the survey of new con-struction.

10. Is it likely that IACS will introduce

common Rules to other areas and ship types?

It is possible, depending upon the successof the new tanker and bulk carrier com-mon rules, that consideration could begiven to other ship types and possibly tothe machinery rules.

Sources: DNV interpretations, JTPRules.com

and IACS Press release of 28th of March,

2006.

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