6.4 Preliminary design description
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Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC.1/Circular.1455 – Guidelines for the Approval of Alternatives and Equivalents as Provided for in Various IMO Instruments – (24 June 2013) - Annex – Guidelines for the Approval of Alternatives and Equivalents as Provided for in Various IMO Instruments - 6 Documentation Requirements - 6.4 Preliminary design description

6.4 Preliminary design description

  6.4.1 A design description comprises the material available on the design, including any risk-based features, describing the project to the extent possible in this phase, as follows. Such a description comprises many elements which are of importance in relation to the understanding of the approval procedure. This section provides guidance on documentation to be submitted as well as considerations by the Administration upon receipt.

6.4.2 Procedural intent, initial considerations

  6.4.2.1 Description of the alternative and/or equivalency design

 High-level description of the design submitted for approval, including the documentation quoted in the documentation section. Definition of the design basis comprising various environmental conditions, intended goal (objectives) of the design and operational scheme (including operational limitations) should be clarified.

  6.4.2.2 Functional description

 The scope of the design in operation must be described in detail.

  6.4.2.3 Identification of interfaces between the alternative and/or equivalency and other systems/operations

 This applies only to project categories 2-4, table 2.

  6.4.2.4 Design approval basis documents

 The design approval basis documents outline how initial owner requirements are met and provide information on tools applied, statements of preliminary tests/simulations performed and ensuing decision support processes.

  6.4.2.5 Preliminary general arrangement drawing

 Provides an overview with dimensions of the project (identical to conventional process).

  6.4.2.6 Preliminary detail drawing of subsystems

 Provides an overview of the systems and their function within the ship (identical to conventional process).

  6.4.2.7 List of codes and standards applied

 The list of codes and standards applied is needed for transparency. If ambiguity exists on the applicability of any codes and standards adhered to, statements of further intended examinations to document applicability of such standards or intentions of testing to marine codes or standards may be submitted with the documentation as per below.

  6.4.2.8 Risk assessment plans

 This applies only to project categories 2-4, table 2. This describes risk assessment as deemed necessary by the Submitter. This allows the Administration to evaluate whether the detail level contemplated is sufficient. The effort applied and the detail of assessment and analysis depend on experience with the design (or similar designs) in the intended application.

  6.4.2.9 Testing and analysis plan

 This applies to project categories 1 to 4, table 2. Any plans for testing or analysing materials, structures or systems which require documentation beyond what is currently available. Tests may be substituted by documentation of the material or system having a track record in another but relevant field.

  6.4.2.10 High-level conclusion

 Provides a brief summary, conveying the options to commence the detailed process.

6.4.3 Documentation to be delivered

 Description of the alternative and/or equivalency design

  6.4.3.1 The Submitter supplies (the examples below refer to risk-based ship design):

  • .1 preliminary main dimensions, preliminary overall shape and configuration, calculations of weights, hydrostatics, stability calculations, etc.;

  • .2 speed, capacity and any further relevant particulars;

  • .3 material data sheets for materials planned for use during construction, particularly where restrictions on the application of such materials exist; and

  • .4 a list of regulations challenged at this stage, if any, to the best knowledge of the Submitter.

  6.4.3.2 The Administration previews to provide verification of the documentation on:

  • .1 whether the description supplied is sufficient information to commence the process; and

  • .2 whether agreement exists on the identified list of regulations challenged.

 Functional description

  6.4.3.3 The Submitter supplies:

  • .1 description of modes of operation and intended area of service;

  • .2 specific operational parameters, including estimates of limitations bearing in mind any novel characteristics;

  • .3 function statements and planned inherent safety features (electric/hydraulic, power packs, redundancies, overload switches), main pressures and voltages where applicable; and

  • .4 drawings, wiring diagrams and piping plans as well as presumed maintenance and operating requirements.

  6.4.3.4 The Administration previews to provide verification of the documentation on whether all safety critical functions and processes have been included and described concisely.

 Identification of interfaces between alternatives and/or equivalencies and other operations

  6.4.3.5 The Submitter supplies a description of the items where alternative design features are deemed to interact with conventional features.

  6.4.3.6 The Administration previews to provide verification of the documentation on:

  • .1 whether all potential items of interaction are included and described to a comprehensive level of detail; and

  • .2 whether all identified rules challenged as shown in the list are addressed and the potential impacts described.

 Design approval basis documents

  6.4.3.7 The Submitter supplies:

  • .1 identification of the design parameters, addressing the nature of operational requirements;

  • .2 the principles underlying the design; and

  • .3 calculations and descriptions of assumptions made, including limitations.

  6.4.3.8 The Administration previews to provide verification of the documentation on:

  • .1 whether the design approval basis documents are considered to be complete;

  • .2 whether safety has been considered and included as a design parameter;

  • .3 whether simplifications applied when analysing the design provide an adequate level of accuracy; and

  • .4 whether tools applied in the process are approved or subject to approval.

  6.4.3.9 Preliminary general arrangement drawings: identical to conventional approval process.

  6.4.3.10 Preliminary detail drawing of subsystems: identical to conventional approval process.

 List of Codes and standards applied

  6.4.3.11 The Submitter supplies:

  • .1 codes or standards adhered to;

  • .2 scope of codes and standards adhered to;

  • .3 requirements challenged in the alternative and/or equivalency ship design;

  • .4 type approvals achieved for components or subsystems, if any; and

  • .5 documentation of applicability of any code or standard, as well as any exemption, deviation or non-compliance.

  6.4.3.12 The Administration previews to provide verification of the documentation on:

  • .1 whether standards complied with are relevant and sufficient;

  • .2 whether applicability is documented to the satisfaction of the Administration;

  • .3 whether certificates or statements of compliance are available and up to date; and

  • .4 whether required examinations are carried out by accredited bodies or labs.

 Risk assessment

  6.4.3.13 The Submitter supplies:

  • .1 risk assessment as deemed necessary by the Submitter in accordance with the assessment of deviation from a conventional design;

  • .2 a description of proposed risk evaluation criteria;

  • .3 a description of risk assessment with regard hereto, including statement on techniques of choice, the applicability of techniques, tools, and proposed preliminary depth level; and

  • .4 a list of proposed participants in the risk assessment team and their qualifications.

  6.4.3.14 The Administration previews to provide verification of the documentation on:

  • .1 whether the risk assessment planned by the Submitter would provide an adequate level of assessment and analysis;

  • .2 whether the evaluation criteria chosen are acceptable;

  • .3 whether the techniques chosen by the Submitter are adequate for the scope of assessment/analysis; and

  • .4 whether the aggregate qualifications of the risk assessment team are considered adequate for the task.

 Testing and analysis plan

  6.4.3.15 The Submitter supplies:

  • .1 tests and analyses plans to validate the applicability of materials or systems for their intended use; and

  • .2 statements of methods and details of labs performing tests and analyses to validate materials or systems.

  6.4.3.16 The Administration previews to provide verification of the documentation on:

  • .1 whether all relevant materials and systems will be tested or analysed;

  • .2 whether methods are acceptable; and

  • .3 whether the labs performing the tests are recognized and accredited or subject to accreditation within a reasonable time frame.

 High-level conclusion

  6.4.3.17 The Administration supplies the following to the Submitter:

  • .1 high-level conclusion of the preview (acceptable/conditionally acceptable/not acceptable);

  • .2 statement of areas which may contain further challenges;

  • .3 terms of adherence to intended approval method (viability considerations); and

  • .4 evaluation of the time frame for approval, if possible.

  6.4.3.18 Queries by the Administration, preceding preliminary approval:

  • .1 Does the design description supply sufficient information to give a broad understanding of the project?

  • .2 Does the Approval Authority agree with the rules applicable and challenged (potential further rule challenge)?

  • .3 Is it possible to initiate the process on the basis of the documentation submitted and available?

  • .4 Have provisions for dealing with any instances yet to be evaluated been considered?

  • .5 Do these provisions appear adequate?

  • .6 Do all stakeholders participating in the process understand the implications in terms of resources assigned, time limits, etc.?


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