Tanker at Loading Terminal
1 Jan

IMO Tanker Damage Rules


Resolution MEPC.248(66) entered into force as of January 1st 2016, so each tanker has to be equipped with a loading instrument which is capable of verifying compliance with intact and damage stability requirements approved by the Administration having regard to the performance standards recommended by the Organization.

In the 66th session of the Marine Environment Protection Committee (MEPC 66) of IMO, the amendments to MARPOL Annex I Ch.4 and the IBC/BCH Code regarding the compliance of the oil tankers to damage stability regulations were agreed. The Resolution (MEPC.248[66]) which was adopted on April 2014 entered into force on 1st January 2016. Similar resolutions (MSC.369[93] and MSC.377[93]) were adopted on May 2014 for tankers carrying dangerous chemicals and liquefied gases.

According to the new rules:

All tankers should be fitted with a stability instrument, capable of verifying compliance with intact and damage stability requirements, approved by the Administration.

The new requirement is retroactive and applies to both new and existing ships as follows:

  • -Ships constructed on or after 1st January 2016 – at delivery
  • -Ships constructed before 1st January 2016 – at the first renewal survey on or after 1st January 2016, but no later than 1st January 2021

Stability Requirements. Ships in operations have some aboard documentations to confirm the compliance with appropriate and applicable stability requirements. These documents which should be approved by the administration can be called as Stability Information Booklets (SIB). The SIB is usually prepared at the time of construction and provides limited information about some standard and possible loading conditions. There are thoughts such as the damage stability criteria can be met by an Approved SIB which has all anticipated conditions, for the vessels on a dedicated service, with a limited number of permutations of loading. However, in practice, it is not always possible to operate the exact same condition which approved in the SIB. For ships carrying liquid cargoes, even a small change in the filling level of the tank or the density of the liquid, can have significant impact on whether compliance is maintained. It is also not possible to prepare an approved SIB including all possible loading scenarios that a ship may operate. The only way to make it possible to check all the loading conditions that a vessel may operate is a computerized instrument onboard.


A Loading Computer is an onboard computer based system for calculation and control of the actual loading conditions for compliance with the applicable stability and strength requirements. It does not mean a loading computer is an alternative to the Approved Stability Information Booklet. It is a supplement that allows the user to instantly calculate and control of every loading condition that a ship may operate in her lifecycle. According to the International Association of Classification Societies (IACS) there are three types of calculations performed by stability software are acceptable depending upon a vessel’s stability requirements. Type-I Software calculating intact stability only (for vessels not required to meet a damage stability criterion), Type-II Software calculating intact stability and checking damage stability on basis of a limit curve (e.g. for vessels applicable to SOLAS Part B- 1 damage stability calculations, etc.) or previously approved loading conditions and Type-III Software calculating intact stability and damage stability by direct application of preprogrammed damage cases for each loading condition (for tankers etc.).


AydenLoad is a new generation ship loading and cargo management software. The Direct Calculation Algorithm of AydenLoad uses the 3D model of the vessel as basis for the calculations. By using the full geometrical definitions of the vessel as the basis for computation, the precise status for condition is being simulated. Additional features based have been developed for a flawless load planning and condition handling. It is the Type-III Software and compliant with the IACS UR L5 requirements for approved onboard Loading Computers that makes it capable of verifying compliance with intact and damage stability requirements for all types of vessels. AydenLoad has been developed to meet the demands of ship owners and ship operators. It is equipped and optimized with all the essential tools for usage of the onboard crew so it does not only ensure that your vessel is compliant with the applicable requirements, it will also provide you to maximize the cargo without compromising safety. Therefore with AydenLoad, you will be in possession of a powerful and versatile cargo planning and stability program that will remain up-to-date at all times.

Ayden Marine - your solution partner with specialized staff and support

As a result of the new rules entered into force on January 1, 2016, it is the responsibility of ship owners or ship operators to ensure that their vessels are compliant within the due date. The situation for vessels built on or after January 1, 2016 are quite clear (should be compliant at delivery) while the situation for existing vessels may seem a little more complicated. Existing vessels which do not have a loading software must have a software that meets the requirements within the terms granted to them. Vessels currently operating with an approved loading program must be sure that their program is capable of verifying compliance with the new requirements. It is known that the old programs used in most of the existing ships can not meet the new requirements. It would be a mistake to think that such programs (or the programs which are authorized only to check whether a loading condition is in compliance with the strength limits, not authorized to check stability requirements) would be compliant with the new regulation, just because they are 'Approved'. Ayden Marine is proposing to work with you to ensure that this process goes smoothly. In addition to delivering products compliant with the damage stability regulations to new vessels, Ayden Marine also provides information to already-operating vessels about where their vessels are in terms of compliance and what to do to comply with the regulations. While the implementation for existing ships is based on survey date, it should be noted that the process is time-consuming, such as the customization of the software for the vessel and approval by the administration. Please do not hesitate to contact us for more detailed information about your vessel.