Unified Interpretations


Unified Interpretations are adopted resolutions on matters arising from implementing the requirements of IMO Conventions or Recommendations. Such adopted resolutions can involve uniform interpretations of Convention Regulations or IMO Resolutions on those matters which in the Convention are left to the satisfaction of the Administration or vaguely worded.

Interpretations are circulated to Administrations concerned or are sent to IMO for information, as appropriate.


  1. IACS, as an international Non-Governmental Organization having observer status at IMO, works in co-operation with IMO in order to endeavour that regulations developed at IMO are clear, unambiguous and can easily be applied without the need of interpretations.
  2. However, interpretations may still be needed in cases where IMO regulations contain only functional requirements, allow alternative solutions to prescriptive requirements, are left to the satisfaction of Administrations or are generally or vaguely worded.
  3. The following Unified Interpretations (UIs) have been developed by IACS to assist the unified implementation of IMO regulations falling in the above-mentioned cases. It should be noted that the development of IACS Unified Interpretations (UIs) is not aiming at introducing additional requirements but at achieving uniform application of IMO regulations.
  4. IACS UIs are to be applied by IACS Societies to ships whose flag Administrations have not issued definite instructions on the interpretation of the IMO regulations concerned, in the course of statutory certification on behalf of those flag Administrations.

The technical backgrounds (development histories) of Unified Interpretations since 2004 can be found by following this link.

A list of the IACS working groups responsible for each Unified Interpretation may be found here.

UI SC113 New

UI SC113 Emergency Towing Arrangements on Tankers - Prototype Test - (Resolution MSC . 35 (63), 2.10) - 1996

UI SC114 Rev1 CLN

UI SC114 Emergency Fire Pump Access (Reg. II-2/ - Rev.1 Nov 2005

UI SC115 Deleted

UI SC115 Fire detection system with remotely and individually identifiable detectors (FSS Code, Ch. 9, and Deleted Oct 2015.

UI SC116 Deleted

UI SC116 Fire detection system with remotely and individually identifiable detectors Deleted in Nov 2005 because of SOLAS 2000 Amendments.

UI SC117 Rev2 CLN

UI SC117 Fire detection system with remotely and individually identifiable detectors (FSS Code, Ch. 9, 2.1.4 and - Rev.2 Nov 2005

UI SC118 Rev2 CLN

UI SC118 Exhaust duct from galley ranges (Reg. II-2/ and - Rev2 July 2015 Clean

UI SC119 Rev1 CLN

UI SC119 Balancing ducts (Reg. II-2/ and Reg. II-2/9.4.2) - Rev.1 Nov 2005

UI SC120 Rev2 CLN

UI SC120 Access to forecastle spaces on tankers SOLAS regulations II-2/ and, IBC Code paragraph 3.2.3 and IGC Code paragraph 3.2.4 Restriction on boundary openings - Rev.2 Aug 2006

UI SC121 Rev1 CLN

UI SC121 Fire Pump Isolation Requirements (Reg. II-2/ - Rev.1 Nov 2005

UI SC122 Rev1 Corr1 CLN

UI SC122 Corrosion Prevention in Seawater Ballast Tanks (Chapter II-1, Regulation 3-2) - Rev.1 Corr.1 Oct 2008

UI SC123 Rev3 CLN

UI SC123 Machinery Installations - Service Tank Arrangements Reg. II-1/26.11 - Rev.3 Dec 2005

UI SC124 Rev1 Corr1 CLN

UI SC124 Emergency Source of Power in Passenger and Cargo Ships Reg. II-1/42.3.4 and II-1/43.3.4 - Rev.1 Corr.1 Oct 2007

UI SC125 Rev2 Corr1 CLN

UI SC125 B and C Class Divisions (Reg. II-2/3.4 and Reg. II-2/3.10) - Rev.2 Corr.1 January 2010 Clean

UI SC126 Rev2 CLN

UI SC126 Fire Protection Materials for Cargo Ships (SOLAS regulations II-2/5.3 and 6.2) Rev.2 Nov 2005

UI SC127 Rev2 CLN

UI SC127 Paints, varnishes and other finishes (Reg. II-2/6.2) - Rev.2 November 2005

UI SC128 Rev2 CLN

UI SC128 CO2 Discharge Time (Reg. II-2/, FSS Code, Ch. 5, - Rev.2 Nov 2005

UI SC129 Rev2 CLN

UI SC129 Fire Detection in Unmanned Machinery Spaces (Reg. II-2/7.4) - Rev.2 Nov 2005

UI SC130 Rev2 CLN

UI SC130 Fire Detection and Sprinkler Systems in Refrigerated Chambers and Similar Spaces (Reg. II-2/7.5.2 and Reg. II-2/ (Reg. II-2/41-2.5 as contained in MSC24(60), FSS Code, Ch. 8, 2.1.1) - Rev.2 Nov 2005

UI SC131 Deleted

UI SC131 Liquid Cargoes for which regular foam is not effective for Fire Fighting Deleted in Nov 2005 because of SOLAS 2000 Amendments.

UI SC132 Rev4 CLN

UI SC132 Release Operation of the CO2 System FSS Code, Ch 5, (as amended by MSC.339(91)) - Rev.4 November 2013 CLN

Forgotten Password

Please enter your email address here and you'll receive an email with instructions on how to reset your password.