1.6 Surveys and certification
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - International Codes - 2009 MODU Code - Code for the Construction and Equipment of Mobile Offshore Drilling Units, 2009 – Resolution A.1023(26) - Chapter 1 - General - 1.6 Surveys and certification

1.6 Surveys and certification

  1.6.1 Each unit should be subject to the surveys specified below:

  • .1 an initial survey before the unit is put in service or before the certificate is issued for the first time;

  • .2 a renewal survey at intervals specified by the Administration but not exceeding five years except where paragraph 1.6.11.2.1, 1.6.11.5 or 1.6.11.6 is applicable;

  • .3 an intermediate survey within three months before or after the second anniversary date or within three months before or after the third anniversary date of the certificate, which should take the place of one of the annual surveys specified in paragraph 1.6.1.4;

  • .4 an annual survey within three months before or after each anniversary date of the certificate;

  • .5 a minimum of two dry-dock surveys during any five-year period, except where paragraph 1.6.11.5 is applicable. Where paragraph 1.6.11.5 is applicable this five-year period may be extended to coincide with the extended period of the validity of the certificate. In all cases the intervals between any two such surveys should not exceed 36 months;

  • .6 radio station surveys in accordance with section 11.9; and

  • .7 an additional survey as the occasion arises.

  1.6.2 The surveys referred to in paragraph 1.6.1 should be carried out as follows:

  • .1 the initial survey should include a complete inspection of the structure, safety equipment and other equipment, fittings, arrangements and material to ensure that they comply with the provisions of the Code, are in satisfactory condition and are fit for the service for which the unit is intended;

  • .2 the renewal survey should include an inspection of the structure, safety equipment and other equipment as referred to in paragraph 1.6.2.1 to ensure that they comply with the provisions of the Code, are in satisfactory condition and are fit for the service for which the unit is intended;

  • .3 the intermediate survey should include an inspection of the structure, fittings, arrangements and safety equipment to ensure that they remain satisfactory for the service for which the unit is intended;

  • .4 the annual survey should include a general inspection of the structure, safety equipment and other equipment as referred to in paragraph 1.6.2.1, to ensure that they have been maintained in accordance with paragraph 1.6.6.1 and that they remain satisfactory for the service for which the unit is intended;

  • .5 the dry-dock survey and the inspection of items surveyed at the same time should be such as to ensure that they remain satisfactory for the service for which the unit is intended. An Administration may allow underwater inspections in lieu of a dry-dock survey provided that they are satisfied that such an inspection is equivalent to a dry-dock survey;

  • .6 the radio survey should be sufficient to assure compliance with the relevant provisions for cargo ships of SOLAS chapter IV; and

  • .7 an additional survey, either general or partial according to the circumstances, should be made after a repair resulting from investigations prescribed in paragraph 1.6.6.3, or wherever any important repairs or renewals are made. The survey should be such as to ensure that the necessary repairs or renewals have been effectively made, that the material and workmanship of such repairs or renewals are in all respects satisfactory, and that the unit complies in all respects with the provisions of the Code.

  1.6.3 The intermediate, annual and dry-dock surveys referred to in paragraphs 1.6.2.3, 1.6.2.4 and 1.6.2.5 should be endorsed on the certificate.

  1.6.4 As an alternative to the renewal and intermediate surveys provided for in paragraphs 1.6.2.2 and 1.6.2.3 respectively, the Administration may, at the owner’s request, approve a continuous survey programme provided that the extent and frequency of the surveys are equivalent to renewal and intermediate surveys. A copy of the continuous survey programme, together with the record of the surveys, should be kept on board the unit and the certificate annotated accordingly.

  1.6.5.1 The inspection and survey of the units, so far as regards the enforcement of the provisions of the Code and the granting of exemptions therefrom, should be carried out by officers of the Administration. The Administration may, however, entrust the inspections and surveys either to surveyors nominated for the purpose or to organizations recognized by it.

  1.6.5.2 An Administration nominating surveyors or recognizing organizations to conduct inspections and surveys as set forth in paragraph 1.6.5.1 should as a minimum empower any nominated surveyor or recognized organization to:

  • .1 require repairs to a unit; and

  • .2 carry out inspections and surveys if requested by the appropriate authorities of a port or coastal State.

The Administration should notify the Organization of the specific responsibilities and conditions of the authority delegated to nominated surveyors or recognized organizations.

  1.6.5.3 When a nominated surveyor or recognized organization determines that the condition of the unit or its equipment does not correspond substantially with the particulars of the certificate or is such that the unit is not fit to operate without danger to the unit, or persons on board, such surveyor or organization should immediately ensure that corrective action is taken and should in due course notify the Administration. If such corrective action is not taken the certificate should be withdrawn and the Administration should be notified immediately; and, if the unit is in an area under the jurisdiction of another Government, the appropriate authorities of the port or coastal State should be notified immediately. When an officer of the Administration, a nominated surveyor or recognized organization has notified the appropriate authorities of the port or coastal State, the Government of the port or coastal State concerned should give such officer, surveyor or organization any necessary assistance to carry out their obligations under this regulation. When applicable, the Government of the port or coastal State concerned should ensure that the unit should not continue to operate until it can do so without danger to persons, the environment or the unit.

  1.6.5.4 In every case, the Administration should fully guarantee the completeness and efficiency of the inspection and survey, and should undertake to ensure the necessary arrangements to satisfy this obligation.

  1.6.6.1 The condition of the unit and its equipment should be maintained to conform with the provisions of the Code to ensure that the unit in all respects will remain fit to operate without danger to persons, the environment or the unit.

  1.6.6.2 After any survey of the unit under this regulation has been completed, no change should be made to structure, equipment, fittings, arrangements and materials covered by the survey, without the sanction of the Administration.

  1.6.6.3 Should an incident occur, or a defect be discovered, which affects the safety of the unit or the efficiency or completeness of the structure, equipment, fittings, arrangements or materials, the person in charge or the owner of the unit should report the incident or defect at the earliest opportunity to the Administration. In addition, the nominated surveyor or recognized organization responsible, who should cause investigations to be initiated, should determine whether a survey is necessary. If the unit is in an area under the jurisdiction of another Government, the person in charge or the owner of the unit should also report the incident or defect immediately to the appropriate authorities of the port or coastal State and the nominated surveyor or recognized organization should ascertain that such a report has been made.

  1.6.7 A certificate called a Mobile Offshore Drilling Unit Safety Certificate (2009) may be issued after an initial or renewal survey to a unit which complies with the provisions of the Code. The Certificate should be issued or endorsed either by the Administration or by any person or organization recognized by it. In every case, that Administration assumes full responsibility for the certificate.

  1.6.8 Any exemptions granted under section 1.4 should be clearly noted on the Certificate.

  1.6.9 A Contracting Government to both SOLAS and the 1988 LL Protocol may, at the request of the Administration, cause a unit to be surveyed and, if satisfied that the provisions of the Code are complied with, should issue or authorize the issue of a certificate to the unit and, where appropriate, endorse or authorize the endorsement of a certificate on the unit in accordance with the Code. Any certificate so issued should contain a statement to the effect that it has been issued at the request of the Government of the State the flag of which the unit is entitled to fly, and it should have the same force and receive the same recognition as a certificate issued under paragraph 1.6.7.

  1.6.10 The certificate should be drawn up in the form corresponding to the model given in the appendix to the Code. If the language used is neither English nor French, the text should include a translation into one of these languages.

  1.6.11.1 The Mobile Offshore Drilling Unit Safety Certificate (2009) should be issued for a period specified by the Administration which should not exceed five years.

  1.6.11.2.1 Notwithstanding the provisions of paragraph 1.6.11.1, when the renewal survey is completed within three months before the expiry date of the existing certificate, the new certificate should be valid from the date of completion of the renewal survey to a date not exceeding five years from the date of expiry of the existing certificate.

  1.6.11.2.2 When the renewal survey is completed after the expiry date of the existing certificate, the new certificate should be valid from the date of completion of the renewal survey to a date not exceeding five years from the date of expiry of the existing certificate.

  1.6.11.2.3 When the renewal survey is completed more than three months before the expiry date of the existing certificate, the new certificate should be valid from the date of completion of the renewal survey to a date not exceeding five years from the date of completion of the renewal survey.

  1.6.11.3 If a certificate is issued for a period of less than five years, the Administration may extend the validity of the certificate beyond the expiry date to the maximum period specified in paragraph 1.6.11.1, provided that the surveys when a certificate is issued for a period of five years are carried out.

  1.6.11.4 If a renewal survey has been completed and a new certificate cannot be issued or placed on board the unit before the expiry date of the existing certificate, the person or organization authorized by the Administration may endorse the existing certificate and such a certificate should be accepted as valid for a further period which should not exceed five months from the expiry date.

  1.6.11.5 If a unit at the time when a certificate expires is not in the place in which it is to be surveyed, the Administration may extend the period of validity of the certificate but this extension should be granted only for the purpose of allowing the unit to proceed to the place in which it is to be surveyed, and then only in cases where it appears proper and reasonable to do so. No certificate should be extended for a period longer than three months, and a unit to which an extension is granted should not, on its arrival in the place in which it is to be surveyed, be entitled by virtue of such extension to leave that place without having a new certificate. When the renewal survey is completed, the new certificate should be valid to a date not exceeding five years from the date of expiry of the existing certificate before the extension was granted.

  1.6.11.6 In special circumstances, as determined by the Administration, a new certificate need not be dated from the date of expiry of the existing certificate as provided for in paragraph 1.6.11.2.2 or 1.6.11.5. In these circumstances, the new certificate should be valid to a date not exceeding five years from the date of completion of the renewal survey.

  1.6.11.7 If an annual or intermediate survey is completed before the period specified, then:

  • .1 the anniversary date shown on the relevant certificate should be amended by endorsement to a date which should not be more than three months later than the date on which the survey was completed;

  • .2 the subsequent annual or intermediate survey required by the relevant regulations should be completed at the intervals prescribed by this regulation using the new anniversary date; and

  • .3 the expiry date may remain unchanged provided one or more annual or intermediate surveys, as appropriate, are carried out so that the maximum intervals between the surveys under paragraphs 1.6.1.3 and 1.6.1.4 are not exceeded.

  1.6.11.8 A certificate issued under paragraph 1.6.7 or 1.6.9 should cease to be valid in any of the following cases:

  • .1 if the relevant surveys are not completed within the periods specified in paragraph 1.6.1;

  • .2 if the certificate is not endorsed in accordance with paragraph 1.6.3;

  • .3 upon transfer of the unit to the flag of another State. A new certificate should only be issued when the Government issuing the new certificate is fully satisfied that the unit is in compliance with the provisions of paragraphs 1.6.6.1 and 1.6.6.2. In the case of a transfer between Governments that are Contracting Governments to both SOLAS and the 1988 LL Protocol, if requested within three months after the transfer has taken place, the Government of the State whose flag the unit was formerly entitled to fly should, as soon as possible, transmit to the Administration a copy of the certificate carried by the unit before the transfer and, if available, copies of the relevant survey reports.

  1.6.12 The privileges of the Code may not be claimed in favour of any unit unless it holds a valid certificate.


Copyright 2022 Clasifications Register Group Limited, International Maritime Organization, International Labour Organization or Maritime and Coastguard Agency. All rights reserved. Clasifications Register Group Limited, its affiliates and subsidiaries and their respective officers, employees or agents are, individually and collectively, referred to in this clause as 'Clasifications Register'. Clasifications Register assumes no responsibility and shall not be liable to any person for any loss, damage or expense caused by reliance on the information or advice in this document or howsoever provided, unless that person has signed a contract with the relevant Clasifications Register entity for the provision of this information or advice and in that case any responsibility or liability is exclusively on the terms and conditions set out in that contract.