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We now have two major regulations addressing the safety aspects, the new IGC Code applicable to all gas- carriers and also the draft IGF Code applicable to gas fueled ships with propulsion and auxiliary systems.
IGC Code
The new IGC Code has been approved by IMO with the Resolution MSC.370(93) and applies to ships whose keels are laid, or which are at similar stage of construction where construction identifiable with the ship begins and assembly of that ship has commenced, comprising at least 50 tonnes or 1% of the estimated mass of all structural material, whichever is less, on or after 1 July 2016. Gas carriers, in particular LNG carriers, have excellent safety records, With the tremendous increase of the gas transportation at sea, with the increase of players in this market, it is essential to assure that these records are maintained even in the future and that measures are taken to extend as far as possible the safety using the collected experience, near misses and new technologies. The new IGC Code introduces new requirements for advanced analysis, including dynamic loads, buckling considerations, crack propagations analysis, detail fatigue analysis, etc. Risk Analysis, according with the new IGC Code is a very important tool to assess new designs, new concepts and also to verify the overall safety to existing designs and practices.
A “high level” guideline on a sound risk analysis process is given in Chapter 1 of the new IGC Code as it follows:
- Methodology and standard applied
- Potential scenario variations
- Validation of risk assessment process
- Quality System used for the risk assessment process
- Know-how of persons performing the assessment
- Distribution system of the results
- Results validation
Identification of risks is to be considered, but not limited to, for ships engaged in the above operations:
- Fire and explosion
- Evacuation
- Extension of hazardous areas
- Pressurized gas discharge to shore
- High pressure gas venting
- Process upset conditions
- Storage and handling of flammable refrigerants
- Continuous presence of liquid /vapor cargo outside the containment system
- Tank over / under pressure
- Ship to ship cargo transfer
- Collision during berthing and validation
IGF Code
IMO issued on 24 April 2014 a new draft IGF Code which is not mandatory. The IMO MSC is supposed to discuss again the IGF Code in their meeting of mid-November 2014. Gas Carriers and LNG Carriers, in particular, have excellent safety records compared with other categories of vessels. The main concern about the possible growth of a large number of dual fuel vessels is that the present safety level assured by vessels complying with IGC Code might not be continued with the increase of gas fueled vessels. This concern is mainly coming from the following considerations:
- Dual fuel vessels are likely to be used everywhere in the world, including very congested areas, restricted areas, close to city and in highly populated areas, rivers, etc.
- Dual fuel vessels will require a large number of bunkering operations; many will actually be transshipping operations which are potentially dangerous.
- The lack of knowledgeable, skilled and appropriately trained officers and crew
- These concerns are delaying the issuance of the new IGF Code, which drafts have been reviewed several times. While the first draft where less severe that the IGC Code, it appears the some aspects of the latest draft are even more severe than the IGC Code.
- As an example the minimum distance of the gas tanks from side shell has been increased in the last draft IGF with respect to the requirements of the new IGC Code. Now for dual fuel vessels other than gas carriers it is required a minimum distance similar to the one required by the IGC Code for type 1G vessels, which are vessels intended for toxic products.
- Considering the many modifications of the draft IGF Codes so far published and some disagreements still existing between certain Administrations on certain requirements of the Code, it is premature at this stage to make a more detailed analysis on the content of the new IGF Code, as many present requirements might be changed in the next couple of months.
Above article is an edited version of Raffaele Piciocchi’s presentation during 2014 SAFETY4SEA Forum
More details may be found by viewing his Presentation video
