A cruise ship design technical expert today dismissed suggestions that huge modern liners lacked stability.

    The sight of the 114,000-tonne Costa Concordia lying on its side off the coast of Italy has raised questions about the safety of such mega-liners.

    But such gigantic vessels are in fact safer than ever, according to Robert Ashdown, the European Cruise Council's technical, environment and operations director.

    He said today: ''It's just not right to say that the design of the hull of these big ships is unstable. These ships are more stable than they have ever been.

    ''They can stand up to anything the weather can throw at them. They are designed to strict international standards.''

    Ever since the Titanic disaster of 1912, the SOLAS (Safety of Lives at Sea) convention has governed ship safety and has kept the number of ocean tragedies to a minimum.

    Mr Ashdown said: ''There have been improvements to SOLAS over the years and one of the most recent ones was in 2006.

    ''Amendments were made to take account of the ultra-large ships that were being built. These amendments came into force in July 2010. Under the new arrangements a ship should be able to proceed to the nearest port of call after sustaining damage.

    ''If the damage is severe, the ship should be able to stay afloat for three hours so that an orderly evacuation should take place.''

    As well as examining the role the Costa Concordia's captain played in the Italian cruise liner tragedy, investigators will also want to know whether normal safety procedures were followed on board.

    For example, they will seek to find out if there were pre-disaster evacuation drills carried out - with passengers all reporting to muster stations so that they would know what to do and where to go in the event of an incident.

    The investigators will also look into the actions of the crew once the vessel began taking on water.