The US National Transportation Safety Board issued their final report on Norway's 2003 boiler explosion, which eventually caused the ship never to return to service.
While the report at the link mentioned above won't be for everyone, most of it is surprisingly "nontechnical" and interesting reading for those interested in cruise ships.
The Board found fault with the way the boiler was operated over the years, the way it was maintained and the way it was inspected.
It is important to note that NCL accepted responsibility for the accident right away. For those concerned about continued operation, NCL notes that no one who was directly responsible for operation, maintenance or inspection of Norway's boilers is any longer employed by the company, and the line has changed classification societies since the accident.
NCL issued the following statement:
Yesterday, the National Transportation Safety Board (NTSB) released its report on the 2003 S/S Norway steam boiler accident at the Port of Miami. NCL CEO and President Colin Veitch said "as evidenced by the highly technical nature of the discussion and the fact that it took 4½ years to complete the report, this was clearly a unique and unusual accident. NCL immediately accepted responsibility for the accident and compensated all of the victims. The Norway, which was the only steamship in the fleet, was sold in 2004. None of the management or contractors who were involved in the operation, maintenance or inspection of the Norway’s boilers are employed by NCL."
Veitch continued: "We appreciate the Board’s hard work and believe that the lessons learned from the report will benefit both shipping companies and classification societies. As evidenced by the lack of agreement among the investigating experts, NCL does not concur with all of the conclusions in the voluminous report, but we are hopeful that its publication will help bring to a close this tragic event."
As the NTSB noted in its report, in the months following the accident, NCL implemented a number of improvements and preventive measures to enhance its Safety and Environmental Management System (SEMS). NCL’s SEMS is now widely regarded as one of the best safety management systems in the maritime industry.