4.1 General
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - International Codes - 1989 MODU Code – Code for the Construction and Equipment of Mobile Offshore Drilling Units, 1989 – Resolution A.649(16) - Chapter 4 – Machinery Installations for all Types of Units - 4.1 General

4.1 General

  4.1.1 The machinery and electrical requirements contained in chapters 4 to 8 provide an acceptable degree of protection for personnel from fire, electric shock or other physical injuries. The requirements apply to both marine and industrial equipment.

  4.1.2 Codes and standards of practice which have been proven to be effective by actual application by the offshore drilling industry which are not in conflict with this Code, and which are acceptable to the Administration, may be applied in addition to these requirements.

  4.1.3 All machinery, electrical equipment, boilers and other pressure vessels, associated piping systems, fittings and wiring should be of a design and construction adequate for the service for which they are intended and should be so installed and protected as to reduce to a minimum any danger to persons on board, due regard being paid to moving parts, hot surfaces and other hazards. The design should have regard to materials used in construction, and to the marine and industrial purposes for which the equipment is intended, the working conditions and the environmental conditions to which it will be subjected. Consideration should be given to the consequences of the failure of systems and equipment essential to the safety of the unit.

  4.1.4 All machinery, components and systems essential to the safe operation of a unit should be designed to operate under the following static conditions of inclination:

  • .1 when column-stabilized units are upright and inclined to an angle up to 15° in any direction;

  • .2 when self-elevating units are upright and inclined to an angle up to 10° in any direction;

  • .3 when surface units are upright and in level trim and when inclined to an angle of list up to 15° either way and simultaneously trimmed to an angle up to 5° by the bow or stern.

The Administration may permit or require deviations from these angles, taking into consideration the type, size and service conditions of the unit.

  4.1.5 Jacking mechanisms for self-elevating units are in general to be arranged with redundancy so that a single failure of any component does not cause an uncontrolled descent of the unit.


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