THE International Association of Classifications Societies (IACS) has announced rules to improve safety in containership building that arose from the June 2013 sinking of the 8,110-TEU MOL Comfort after it split in two in the Arabian Gulf.
IACS chairman Philippe Donche-Gay has introduced the new rules to the UN's International Maritime Organisation (IMO), saying: "Once again IACS stands ready to assist the IMO in all areas where technical expertise can advance our common goal of safer and cleaner ships."
Two years ago, sea loads aboard the doomed ship were too much for the hull girders to bear, resulting in the ship splitting two and sinking, said a Japanese government inquiry.
The report from the Japanese government's Committee on Large Container Ship Safety said computer simulation showed the hull was weaker than the lateral and vertical bending loads it experienced at the time of the cracking.
The report said that the hull fracture originated from the bottom shell plates in MOL Comfort's midship section.
Amalgamated within a single new Unified Requirement (UR S11A) rule are three new safety measures that provide a "robust, timely and complete response" to the accident.
Work on the rules resulted in the development of a longitudinal strength standard for containerships that addresses bi-axial stresses which would be induced by lateral loading, that is external pressure on the bottom shell of the hull.
This will now be recognised in the new IACS Longitudinal Strength Standard for Containerships, known as Unified Requirement S11A which will enter into force on July 1, 2016.
The whipping effect on containerships are now better understood, and it now required that the whipping component of hull girder loading is taken into account by IACS members by July 1, 2016.
A revised wave bending magnitude and longitudinal distribution has been included in the development of the new Unified Requirement S11A - full details of which will be made available on the IACS website shortly.
By developing a minimum set of common loading conditions amidships, a baseline for structural strength in a cargo hold in the midship region can be achieved, said IACS.
The new S34 rule is applicable to containerships from July 2016 and requires a Global (full ship) analysis for ships with length of 290 metres and a cargo hold analysis for ships with length of 150 metres.
In accordance with IACS commitment to safety and transparency these 50+ pages of new requirements are available on the IACS website along with the detailed technical background.
Source : HKSG.