1.1 Alternative and/or equivalent design
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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 - 1 Introduction - 1.1 Alternative and/or equivalent design

1.1 Alternative and/or equivalent design

  1.1.1 Prescriptive regulations may sometimes restrain the level of innovation that is feasible in design. An essential prerequisite for widespread use of innovative and the use of alternative and/or equivalent design is a predictable and reliable process of submitting and approving the design making full use of state of the art risk assessment tools and techniques.

  1.1.2 There may be different levels of approval depending on how challenging the proposed alternative and/or equivalent design is in light of prescriptive regulations. Such designs may deviate from prescriptive requirements related to certain components, systems or functions or the whole ship. Alternative and/or equivalent design and approval is expected to be carried out only for ship functions, systems or components that either directly or indirectly proposes alternative ways of compliance with prevailing regulations.

  1.1.3 One approach to the approval of an alternative and/or equivalent design is to compare the innovative design to existing designs to demonstrate that the design has an equivalent level of safety. In order to demonstrate an equivalent level of safety, functional requirements and performance criteria should be established for essential ship functions, which should be met by the alternative and/or equivalent design. An alternative approach could be to carry out a risk analysis of the alternative and/or equivalent design and compare it to overall risk evaluation criteria.

  1.1.4 A structured approval processes is necessary in order to confirm that the alternative and/or equivalency design can obtain the required approval along with the necessary certificates related to statutory requirements for their intended operation. The Guidelines presented herein describe such a structured process that is predictable and reliable. By adhering to these Guidelines, Submitters and Administrations would be working in cooperation to evaluate that all aspects of safety and environmental protection are adequately assessed and controlled to an acceptable level. Furthermore it will facilitate innovation.

  1.1.5 Currently, there are provisions in many IMO conventions for acceptance of alternatives and/or equivalents to prescriptive requirements in many areas of ship design and construction. In this context, the Organization has issued several guidelines, such as Guidelines on alternative design and arrangements for fire safety (MSC/Circ.1002), Guidelines on alternative design and arrangements for SOLAS chapters II-1 and III (MSC.1/Circ.1212) and Interim guidelines for the approval of alternative methods of design and construction of oil tankers (resolution MEPC.110(49)).


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