A report on the grounding of the Napoli has suggested a review of the rules used in container ship design.The storm-damaged 53,000-tonne vessel - carrying 2,318 containers - was grounded a mile off Sidmouth, east Devon, in January last year.The crew of 26 abandoned ship and were rescued by two Royal Navy helicopters.The Marine Accident Investigation Branch investigation report said the failure to the hull in the region of the Napoli's engine room was due to the vessel's design rather than her material condition or construction."The MAIB concluded that this, along with the ship's speed and her loading, caused the vessel to break her back as she headed directly into high seas."It has therefore recommended a review of the technical rules used in container ship design."The report continued: "As part of the ongoing investigation the MAIB identified that container ships of similar design could potentially have the same design flaw and have identified that out of 1,500 vessels screened, 12 require work to bring them up to acceptable safety standards."Chief Inspector of the Marine Accidents Investigation Branch, Stephen Meyer, said: "I am very pleased that, at the request of the MAIB, the International Chamber of Shipping and the World Shipping Council have already started work on the development of a Code of Best Practice for the container ship industry."This work will take into account the lessons identified by the MAIB investigation and should lead to a much safer industry."The MAIB has made a series of recommendations to the International Association of Classification Societies to improve the current technical rules regarding container ship design, and to the International Chamber of Shipping and the owners of the vessel Zodiac Maritime Agencies Ltd to make the operation of container ships safer.The 1991-built Napoli was in the Channel en route from Antwerp to Portugal when the engine room flooded after a hull failure about 45 miles south of Lizard Point, Cornwall.The MAIB report said after the Napoli hit "several large waves," there was a "large crashing or cracking sound."The hull failure was due to "lack of buckling strength in the engine room region," said the MAIB report.It said the Napoli was making 11 knots at the time, and a reduction of speed would have "significantly reduced the risk of hull failure."