DE 51 - 51st session of IMO's Sub-committee on Design and Equipment

Last week the 51st session of the IMO's Sub-committee on Ship Design and Equipment (DE 51) took place in Bonn, Germany. A large delegation from INTERTANKO was present to cover developments on a number of important issues on the DE 51 agenda – including the following:


Onboard waste treatment installations

DE 51 completed the revision of a number of relevant regulations in MARPOL Annex I and Annex VI regarding requirements for oily water separators and their installation, the Oil Record Book, and incinerators.


Incinerator capacity

It was agreed to suggest the removal of the Unified Interpretation 15.5 in MARPOL Annex I, which allows the reduction by 50% of oil residues (sludge) tank capacity if there is an incinerator on board. In other words, whether the ship is equipped with an incinerator or not, the capacity of the oil residue (sludge) tanks should be the same. This is in line with the views expressed by INTERTANKO in its submission to DE 51. We also suggested adding a new regulation which would define the performance of the incinerators should these be installed onboard ships. Unfortunately, this suggestion did not receive enough support.


This issue will be passed to the Maritime Safety Committee (MSC 83) for final approval. We do not rule out that there could be further papers submitted to the MSC with data showing that the incinerators are reliable devices and that a reduction in the sludge tank capacity to match the incinerator capacity is justifiable. It is therefore important that INTERTANKO receive factual arguments from members to support the DE 51 decision.


Some of the issues of which we are aware are:

  • lack of reliability of incinerators;
  • trade pattern and the introduction of more Sulphur Emission Control Areas (SECAs);
  • limits as to where the incinerators can be used;
  • whether a ship would be in breach of MARPOL if its incinerator is not working and its sludge tank capacity has been reduced by a volume corresponding to the incinerator capacity.


Draft amendments to the Oil Record Book (ORB)

Some amendments were agreed which would accommodate the clarifications suggested by INTERTANKO with regard to entries D (non-automatic overboard discharge) versus entries E (automatic discharge).


Draft amendments to MEPC.1/Circ.511

A large number of amendments were made to this circular, which contains the Revised Guidelines for Systems for handling oily wastes in the machinery spaces of ships, and which incorporates guidance notes for an Integrated Bilge Water Treatment System (IBTS). These amendments would result in an improved guide on how to design the waste treatment installation. A number of INTERTANKO's suggestions were incorporated into the final draft. INTERTANKO will issue a guide with further details of these changes.


Blanking off ships' discharge piping systems in port

DE 51 agreed with an suggestion by the International Association of Classification Societies (IACS) to strongly recommend that port authorities do not instruct ships to blank off their discharge piping systems in port. To do so could have serious safety consequences in an emergency situation. DE 51 drafted a joint MSC and MEPC circular to be approved by the two main IMO Committees and circulated to Governments.


Paragraphs 27 & 30 - The INTERTANKO DE 51/18/3 proposed IBTS flow chart was explained and received support. However, this flow chart was found to be much more difficult to modify electronically compared to the flow chart originally presented by Japan. It was agreed to do some changes to the Japanese IBTS flow chart and include in the text, e.g., the option of separating the oil flow into one of lube oils and one of fuel oils.


The INTERTANKO suggestion of having an inspection tank in the line for "clean drains" was fully explained and understood, but not supported. The reasons given for the lack of support was that clean drains do not require an inspection tank, and to suggest an inspection tank would only raise suspicion that there is a loop-hole in the regulation. It was further argued that an oil detector in the clean water discharge could be an option.


Possible phase-out of existing Oily Water Separator (OWS) installations

DE 51 did not reach a conclusion on a proposal to consider the phasing out of old oily water separators that cannot handle emulsions.


The reasons in favour of a phase-out were that new equipment is better; that the cost is worth the benefit to both the environment and the ship (it was suggested that a new oily water separator would reduce the amount of oily bilge water pumped ashore); that the operating costs of new equipment is lower; that some makers of the old systems are not in business any longer so that an upgrading of these old systems is not possible, etc.


Those sceptical to the phase-out proposal stated that there was no guarantee that a new oily water separator is always fit for purpose (an example was given of one of the best and most expensive pieces of equipment that clogged up after no more than one hour's operation); the new oily water separators are larger in size and need more space; a phase-out proposal needs to include a proposal for the time frame for certification and class approval. It was also suggested that to do the installation of the new equipment with a ship in service would require a waiver from the administration. Existing systems cannot be changed without approval (Res. A.444).


The United States, which suggested the phase-out, promised to make a resumé of the discussions and revert. We anticipate that this item will come up again at the next Marine Environment Protection Committee (MEPC) meeting. INTERTANKO therefore suggested items that need to be identified before decisions are taken. We would appreciate input from members which would assist INTERTANKO's further participation in these discussions. However, it should be noted that the year 2016 was mentioned as a potential deadline.


Protective Coatings

DE 51 included in its agenda a number of issues related to coating of spaces on ships, the outcome of which was as follows:


- Draft SOLAS regulation for coating of cargo oil tanks

DE 51 did, in practice, conclude on this issue. However, its finalisation is scheduled for 2009, and therefore the issue may be again discussed at DE 52 in February 2009.


The standard (PSPC) for the cargo tank coatings was also completed, but the testing routines for the selection of coatings will be completed next year at DE 52. Click here for an updated version of this draft regulation. The major change from the previous version was the removal of specific language identifying corrosive resistant steel as an alternative means of coating. DE 51 agreed that any alternative means should be allowed as now provided for in paragraph 3.2 of the draft regulation.


- Guidelines for coating maintenance and repairs

Annex 1 of this report includes the latest version of the Guidelines for maintenance and repair of the coatings. These could not be concluded because they do not identify the "areas of concern" on ship types other than oil tankers. IACS was invited to consider and revert with suggestions. As far as tankers are concerned, the work could be considered completed.


- Coating standards for means of access

Annex 2 of this report gives the final mandatory standard for coating of means of access. The standards are now in line with the INTERTANKO approach.


INTERTANKO representatives at DE 51 that dealt with the issues given in this report were Johnny Eliasson, SNTG; Bjarne Thygesen and Dr. Timothy Gunner.  

Contact: Dragos Rauta