The MODU Codes
There are three IMO MODU Codes with four major applicability dates relating to the date that a MODU was constructed (i.e., date the keel was laid, or the unit was at a similar stage of construction):
- The Code for the Construction and Equipment of Mobile Offshore Drilling Units, known as the MODU Code and commonly referred to as the 1979 MODU Code:
- applicable to MODUs constructed on or after 31 December 1981
- The Code for the Construction and Equipment of Mobile Offshore Drilling Units, 1989, also known as the 1989 MODU Code:
- applicable to MODUs constructed on or after 01 May 1991
- The Code for the Construction and Equipment of Mobile Offshore Drilling Units, 2009, also known as the 2009 MODU Code:
- applicable to MODUs constructed on or after 01 January 2012
- 2016 and 2017 amendments are only applicable to MODUs constructed on or after 01 January 2020.
Note: Any existing unit that complies with the requirements of a specific Code is eligible for issuance of a certificate under that Code. For example, a unit that was built prior to the implementation of the 1979 MODU Code (e.g. keel laid date of September 1977) can be issued a MODU Safety Certificate under the 1979 Code if it meets all of the requirements in that Code. Another example is a MODU that was originally constructed to meet the provisions of the 1989 MODU Code but has undergone modifications and complies with 2009 MODU Code requirements could be issued a 2009 MODU Safety Certificate.
The Purpose of the MODU Code(s)
The MODU Code’s purpose is to “provide an international standard for mobile offshore drilling units of new construction so that its application will facilitate international movement and operation of these units and result in a level of safety for such units and for personnel on board equivalent to that required for conventional ships engaged on international voyages by the International Convention for the Safety of Life at Sea, 1974 and the International Convention on Load Lines, 1966” as stated in the preamble to the 1979 MODU Code. The preambles to the subsequent MODU Codes read similarly.
The MODU Codes are used in place of SOLAS for MODUs. The Code of Safety for Special Purpose Ships is not intended to be applied in addition to the applicable MODU Code.
The MODU Codes refer to specific SOLAS regulations and additional IMO Codes such as LSA Code, FSS Code, FTP Code, and various resolutions and circulars. MARPOL applies separately.
MODU Codes amendments
As with other international instruments, build (constructed/keel laid) dates are a crucial factor in determining the MODU Code (’79, ’89 or ’09) and the respective amendments that apply to an individual MODU.
The attached timeline provides a visual representation for the dates associated with the MODU Codes and their amendments.
The “2024 editions” of the OCSNCOE-developed MODU Codes (1979, 1989 and 2009) were updated to include the 2023 amendments that go into effect on January 1, 2024.