Tanker Damage Stability Regulations Will you meet the Grade?

Executive Summary

At MEPC66 (April 2014) the IMO agreed amendments to MARPOL Annex I Ch.4

and the IBC/BCH Code concerning the need for tankers to be able to demonstrate compliance with damage stability regulations. Similar requirements were agreed for gas tankers and the IGC/GC Code at MSC93 (May 2014).

The impact of these regulations has generally been understated however the significance of complying with the amendments is only now being recognised more widely. While the implementation for existing ships is phased based on survey date, they nevertheless will come into effect from January 2016 onward.

This paper provides an insight into the requirements and likely problems to achieve compliance for tanker owners, operators and mariners. It describes the background to the amendments, their implications, and options for complying with them. It also highlights historical issues which may have significant influence on whether a ship can comply based on the existing documentation and systems aboard.

It is likely that many tankers – especially those contracted for construction prior to July 2005 (and thus prior to the IACS UR L5 requirements) - will need to have work done to meet the amended regulations.

The purpose of this paper is to identify ways in which this regulatory necessity may in fact provide benefits rather than simply being another burden on budgets and indeed generate a positive return on any investment needed.

The Regulatory Changes – at a glance

Class Societies including Det Norske Veritas (DnV) and Lloyd’s Register (LR) are issuing advice to owners and operators concerning the impact of these new regulations. DnV outlined the impact of the changes in ‘Statutory Update No. 04, 2015 / May’ as follows:

“New requirements for on-board stability instruments applicable to all tankers will be effective from 1st January 2016. MARPOL Annex I Ch.4, the IBC/BCH Code and the IGC/GC Code have all been amended, requiring tankers to be fitted with a stability instrument capable of handling both intact and damage stability.

The new requirement is retroactive and applies to both new and existing ships as follows:

• Ships constructed on or after 1st January 2016 – at delivery.

• Ships constructed before 1 January 2016 – at the first renewal survey on or after 1st January 2016, but no later than 1st January 2021.

DnV further advised that ships carrying on-board stability instruments already approved and certified by a recognized organization, and capable of verifying both intact and damage stability to a standard acceptable to the administration, may continue to use such an instrument but nevertheless:

It is… the responsibility of each manager to ensure that his vessels are compliant within the due date.”

Stability Regulations – how is compliance checked today?

Most mariners, ship operators and owners will be aware that their ships have aboard documentation to confirm compliance with the appropriate statutory stability requirements. This is normally provided in the form of a Stability Information Booklet (SIB), formally approved by the relevant Flag Administration.

The content of a SIB can vary considerably, is often driven by the planned operational profile of the vessel - and cost – and is usually prepared at the time of build. It will include a range of standard loading conditions but, depending on the vessel, these could cover a multitude of different loading scenarios or just a handful. Over a ship’s lifetime her operational profile may vary, and therefore even an approved SIB should be reviewed to ensure its relevance to the way the vessel is currently operating.

For vessels which carry fluid cargo, the issue of damage stability is complex. The behaviour of the vessel can change significantly depending on the density of the cargo being carried and the filling level in each compartment. Where individual load conditions are provided in the Stability Information Booklet, these are verified to meet the damage stability standard as a matter of course, but a small change to the fluids aboard can have significant effect on whether compliance is maintained.

Vessels which operate consistently on the same route with the same cargo – and therefore adopt the same loading conditions repeatedly – could operate based on the content of a SIB. But where this is not the case, to provide sufficient loading conditions in a SIB to cover all loading possibilities is usually prohibitive in terms of cost and volume of paperwork.

Some tankers are provided with damage limit KG/GM curves in their approved stability documentation. These provide some flexibility, but to make them practical to apply they tend to be derived in a conservative manner. As a result, for some ships the use of limit curves can restrict operability.

Beside the stability compliance issues, for any loaded condition there is also a requirement to demonstrate compliance with Classification Society strength limits. Since the 1970’s this has been accomplished by the provision on-board of a computer loading instrument. Over time the use of these on-board systems has extended to also cover stability aspects. Reference by hand to the approved SIB to verify stability compliance has now rather gone out of fashion, and reliance is instead placed upon these computerised tools – in recent regulations termed Loading Computer Systems (LCS) – to perform this task.

However, it is important to be aware that the formal wording of regulations states that any approved on-board LCS does not replace the Stability Information Booklet, but is a supplement to it. A key point to note here is that the LCS should be ‘approved’.

Your existing on-board LCS – an acceptable solution?

For many years, it has been the case that a loading instrument / LCS has required formal examination and approval by Class before it can be used on a specific ship for strength compliance checks. However the approval of any stability checks provided in those systems was not a requirement until recently.

As a result, many older vessels have systems aboard which have a formal approval certificate, but this may only cover Class strength aspects. Their suitability for use for stability assessment may never have been examined, but they are often considered as a suitable means to demonstrate overall compliance because they are ‘approved’.

In 2005, the International Association of Classification Societies (IACS) began to address this issue through Unified Requirement (UR) L5. For any vessel contracted for construction after July 2005, it became a Class requirement for any stability function provided in an on-board LCS to undergo formal approval. Moreover, the included stability functions would need to cover all the aspects of stability compliance relevant to the ship. This requirement was subsequently echoed by IMO in the 2008 Intact Stability Code.

However neither the IACS or IMO requirements require mandatory inclusion of stability checks. Consequently, while the majority of recently built vessels are likely to have aboard an LCS which is formally approved for use for stability verification, some vessels may have been provided with an approved LCS which only covers strength aspects.

Clearly then, there is no guarantee that a tanker will have aboard anything other than a Stability Information Booklet, and even if an LCS is in use aboard the functionality could vary significantly from that required to demonstrate regulatory compliance. More importantly, some or all of the stability functions may never have been formally examined and approved for use.

Created in Paramarine®

A Quick Assessment of your Ship’s Compliance

START

Does your ship operate only to the specific loading

conditions shown in the Approved Stability Book?

NO

What does this mean for your ship?

In 2010 the Paris MOU undertook a Concentrated Inspection Campaign, and this found that some tankers were operating with loading conditions which did not meet the relevant damage stability regulations. In order to negate this, the amendments to the regulations will now require tankers to have an approved means aboard to verify damage stability compliance.

Clearly the variability in the approved scope of existing on-board tools means their breadth of application needs to be well understood by their users. Those on- board in particular need to have a thorough understanding of what any approval certificate covers, if they have one.

Class Societies are issuing advice to owners to confirm the status for each ship, but this may take time. The attached flow chart is provided to permit a quick assessment prior to receiving any formal notification.

If found to be non-compliant, there are a number of ways in which a vessel could meet the amended regulations, depending on existing documentation, systems and ship operational profile.

The simplest approach is to operate only to the approved loading conditions in the SIB. However, this is rarely practical. Any new loading conditions would require formal case-by-case approval from Class and Flag, which involves time and expense.

Alternatively a range of additional loading conditions could be added to the SIB, or a set of wide-ranging limit KG/GM curves could be developed. But there may still be limitations, it will be voluminous and potentially awkward to use, and again there is a cost to develop the content and gain formal approval of it.

Either way, a computer model of the vessel will be needed to generate the new data. Considering this, the most effective solution would appear to simply have the computer model on-board, to allow new conditions to be generated and verified as needed. This, of course, is the role of an approved Type 3 Loading Computer System.

In this respect, Lloyd’s Register (Class News No.17/2015) advised that:

“To avoid complications associated with developing suitable KG/GM limit curves and their potential restriction on operational capacity, we strongly recommend that Type 3 stability software is fitted on board.”

Does the Approved stability book include damage stability

limit curves covering all operational loaded conditions?

NO

Does your ship have an on-board Loading Computer System (LCS)

which can carry out damage stability calculations?

NO

Either the stability booklet should

be updated to include all operational loading scenarios (either by additional loading

conditions or with damage limit KG/GM curves covering the

operational range of loading) or by providing an on-board

Type 2 or Type 3 LCS.

Flow chart to enable an initial assessment of whether your ship will comply with the amended Regulations.

YES

YES

No further action formally necessary unless benefits can

be seen in procuring efficiency and operational support tools.

YES

YES Do you have an approval

certificate for the on-board LCS (from Flag or designated Class)?

YES

Does the certificate confirm that the on-board LCS is approved for carrying out damage stability

calculations?

NO NO

Many old LCS systems

performing stability calculations are unapproved for that scope. Approval is now mandatory. Some

older systems may not meet current standards and a replacement

Type 2 or Type 3 LCS may be needed (or updates made to the

SIB conditions/limit KG/GM curves).

Approval is now mandatory. Some older systems may not meet current standards for

damage stability calculations and a replacement Type 2 or Type 3 LCS may be needed

(or updates made to the SIB conditions/limit KG/GM curves).

A Solution – with added benefits?

One would assume that it should be cost- effective to simply update any existing on-board LCS system. But, as we have seen, for historical reasons there is no guarantee that an existing on-board LCS will have all the functions needed, or have approval.

Some older LCS systems do not perform damage stability calculations to the standard necessary to meet the current Regulations, and consequently those systems will not be fully upgradable. Many LCS products are described in sales material as ‘Approved by Class’ but the functions actually approved vary significantly from product to product.

To ensure they meet the amended Regulations, all vessels will require a thorough review of systems aboard, and in many cases for older tankers this is likely to highlight a need to procure a new LCS system. While initially this might be viewed as regulatory-driven additional expenditure, it does in fact provide an ideal opportunity to add value to the systems on-board, and in many cases promote a tangible saving in operational costs.

Trends in on-board software development are moving away from performing discrete tasks to providing an integrated system which can exploit opportunities from aspects which traditionally have been treated in a mutually exclusive manner. For example, use of a full 3D model in an LCS enables the cargo deadweight to be maximised and tools within the LCS could allow detailed cargo load and unload planning optimisation to minimise port time: more cargo, less port costs.

Taking this further, these tools can provide a means to perform whole voyage planning, working beyond the load/unload planning stages and assessing the voyage itself, incorporating trim optimisation and ballast water exchange planning in conjunction with weather routing and associated speed/fuel optimisation – striving for ultimate voyage efficiency.

Therefore if an LCS is the preferred solution it should be seen as an investment rather than a cost, as the long term benefits of a quality system, set up optimally for each ship in the fleet, could far outweigh the initial capital expense.

Summary

Amendments to MARPOL Annex I Ch.4, the IBC/

BCH Code and the IGC/GC Code concerning damage stability compliance verification come into force from January 2016. It is likely that many tankers – particularly those contracted for construction prior to July 2005 – will require

updates to existing stability documentation and/ or any systems on-board which are used to assess stability compliance. These will require formal Flag Administration approval.

In many cases, the most cost-effective approach will

be to update (where possible) any existing Loading Computer System. However not all systems can meet the new standards required by Regulations,

and a new LCS may need to be procured. While all options will require capital expenditure, selection of the right LCS could offer significant added benefits.

Owners, operators and mariners need to be aware

of the status of compliance of their existing systems and documentation for each ship in their fleet, and be aware they may need to invest promptly to meet the Regulations.

It should be noted that there are a limited number

of suppliers of suitable LCS systems, and many tankers may need upgrading. Therefore timescales may become a factor, particularly as the work requires both preparation of the LCS and formal

approval by Class or Flag, and so a prompt review is imperative.

About IMCS

QinetiQ International Maritime Consultancy and Software is part of the QinetiQ Group. We provide a range of proven services and solutions to ship builders, ship owners and ship designers covering the entire maritime industry including cruise ships, dry cargo vessels, fast and conventional ferries and offshore support vessels, tankers and gas carriers.

With thirty plus years of maritime experience, we have invested over £100m in test facilities and equipment including one of the world’s largest ocean basins, a 270m towing tank, a cavitation tunnel and super computing capabilities all operated in a highly secure environment.

Our expertise has helped our many customers to solve a wide spectrum of challenges including;

• building requirements and developing concepts for new ships

• optimising vessel performance

• assessing regulatory impact and insuring regulatory conformity

• maintaining and increasing safety levels

• maximising the financial return of operations

Our services include:

• Ship Concept Design Services

• Ship Design Performance Assessment Services

• Ship Design Optimisation Services

• Through Life Capability Support Services

• Maritime Safety & Regulatory Advice Services

Our services are delivered by a team of highly qualified experts in hydrodynamics, naval architecture and ship design, marine engineering, computational fluid dynamics, ship safety, propeller design, complex ship testing and evaluation and human factors.

About SeaWeigh

The QinetiQ SeaWeigh Loading Computer System is an ideal solution to meet the amended Regulations, and be a core element in an integrated system. SeaWeigh is based on a full 3D model of the vessel, and is compliant with the latest standards for stability assessment. It is used extensively on naval vessels, and has gained Lloyd’s Register Class approval accordingly. It is an ideal solution to meet the new tanker damage stability requirements, and has a proven track record.

But SeaWeigh can offer far more than just the means to confirm damage stability compliance. It includes a sophisticated routine for efficient planning of a voyage, and incorporates a range of other practical tools for those on-board.

The QinetiQ products are supported by a dedicated team of Naval Architects and Software Developers, and customer focus is a main driver. Ongoing developments within SeaWeigh have been influenced by input from major tanker operators and on-board system suppliers, and the focus is to add value for clients. Bespoke development work for unusual projects is commonly undertaken.

About the author

Philip Royal graduated with First Class honours in Naval Architecture from The University of Newcastle Upon Tyne in 1987. After 10 years working in the offshore sector, both for design contractors and offshore installation contractors, he took up a role in the Statutory Computational team within Lloyd’s Register (LR) in London.

Over the course of 15 years at LR he gained experience on the approval of stability aspects for a range of ship types, in particular tankers. He was responsible for defining LR’s standards for approval of on-board LCS systems, and was the subject matter expert for Stability Loading Computer Systems.

Philip took up a post with QinetiQ in 2014 to support and promote the development of the SeaWeigh LCS system, working with industry partners to create a client focused on-board system. Given the concerns with tanker damage stability compliance, his aim is that SeaWeigh will become the on-board tool of choice to ensure regulatory compliance, but with added benefits that will also make it the practical tool of choice.

Ultimately the intent is that the efficiency opportunities available through use of SeaWeigh’s practical tools will ensure the cost of procurement to be insignificant compared to the potential financial benefits from use.

QinetiQ Cody Technology Park Ively Road, Farnborough Hampshire, GU14 0LX United Kingdom Tel: +44 (0)2392 334003 Email: IMCS@QinetiQ.com www.QinetiQ.com

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