The mudslinging over who decided the Costa Concordia should sail within 150 metres of the shoreline of an Italian island in a manoeuvre known as a "salute" to show the ship off has exposed wider concerns over how such vast ships should be controlled and how safe they really are.

"During the past two decades, cruise lines have maintained the best safety record in the travel industry," the European Cruise Council reassured holidaymakers on January 14 in response to the capsizing of the Costa Concordia in which at least 16 people died.

Research by Reuters has revealed, however, that patchy safety data and poor accident reporting standards make it difficult to verify how safe the industry really is and impossible for members of the public to easily compare the relative safety standards of different operators.

The lack of a comprehensive, publicly available database of shipping accidents is just one symptom of a loosely regulated industry where international rules under the auspices of the United Nations are wide open to interpretation by national governments, operators and ship captains.

The reassurances given to cruise ship passengers in a second statement from the European Cruise Council on January 16 that "all our member lines are subject to the highest safety standards around the world according to international maritime requirements" may raise some eyebrows.

The blame game between the captain and ship operator Costa Cruises - a unit of U.S. giant Carnival (CCL.N) (CCL.L) - over whose fault it was that he sailed so close to shore as to run aground and passenger criticism of emergency procedures have prompted questions over industry safety standards, particularly as there would have been many more casualties had the ship gone down on the high seas.

Adding to the growing debate, Franco Gabrielli - head of Italy's Civil Protection authority which is coordinating the rescue operations - said over the weekend that a number of unregistered passengers may have been on board. Costa denied there were any stowaways on board.

Highlighting how open to interpretation international shipping rules are, Chapter 5 of the International Convention for the Safety of Life at Sea agreed in 1974 requires that member states ensure that "from the point of view of safety of life at sea, all ships shall be sufficiently and efficiently manned". There are no agreed minimum staffing levels.

The U.N.-affiliated International Maritime Organisation IMO.L did adopt additional guidelines for "minimum safe manning" in November 2011 but the principles are, in its own words, broad ones and put the onus on governments under whose flag the ships are sailing.

FULL OF HOLES

Rules on reporting accidents are also short on enforceable specifics.

The 1974 convention, for instance, only required governments to supply the IMO with "pertinent findings" from investigations in the wake of accidents and undertook that any reports or recommendations based on such filings would not disclose the identity or nationality of the ships concerned or apportion blame for any incident.

Guidelines on investigating and reporting casualties have been amended over the years but there's still plenty of wiggle room. Under resolutions adopted in 1999, operators were told only that reports into incidents should be "distributed to relevant parties involved and should preferably be made public" while pooled information on casualties was to be made available in an electronic format to governments but not to the general public.

Even under revised harmonised reporting procedures published in a Maritime Safety Committee circular dated December 18, 2008, governments are asked only to supply the IMO with "pertinent information" concerning the findings of investigations. The circular is characterised by words such as "requested", "urged" and "invited".

The result is that even the IMO's own database of Marine Casualties and Incidents is incomplete.

Costa Concordia owner Carnival, for instance, outlines in its 2010 sustainability report details of an accident in which another member of the Costa Cruises fleet - the Costa Europa - collided with a pier while docking in the port of Sharm el-Sheikh, Egypt, causing a hole in the ship, killing three members of the crew and injuring four passengers.

This accident does not appear on the IMO database. Nor, in fact, does another incident outlined in the same Carnival report when on July 12, 2010 a diver inspecting its Holland America Line cruise ship Noordam drowned.

The most recent Costa Concordia incident off the coast of Italy is recorded on the IMO database. So too is a near miss - a so-called close-quarter situation - involving the Costa Atlantica, which in 2008 came too close to the Panamanian registered car carrier Grand Neptune in the Dover Strait between Britain and France. The cruise ship was crossing a traffic separation zone which is shipping's answer to a one-way street and designed to reduce the chances of collisions in busy shipping lanes.

UNREPORTED

The IMO database lists 38 incidents involving passenger ships since 2005 in which more than 60 people died. The incidents, which include ferries, range in severity from momentary groundings with little damage and no injuries to the loss of the ship and several lives. What data there are, show Carnival as owner of 12 of the 38 ships to get into trouble while Royal Caribbean International was operator of three, as was Fred Olsen. The others have not been identified or belonged to smaller, local cruise or ferry companies.

A recent report by industry analysts Cruise Market Watch showed Carnival had a 49.2 percent share of the global cruise market followed by Royal Caribbean with 23.8 percent.

For the period since 2000, the IMO database has recorded just under 300 incidents involving passenger-carrying vessels ranging from near misses to sinkings although prior to 2005 the details available in relation to any given accident are often patchy.

Data compiled by sociologist Professor Ross Klein of Memorial University Newfoundland, who in 2007 testified before a U.S. congressional hearing into cruise safety but whose findings have often been disputed by the industry, indicates the rate of reportable accidents could be much higher, however.

Klein's data, which he posts on his website www.cruisejunkie.com, suggest that for cruise ships alone there have been 368 disabling events such as fires, 174 persons overboard, 75 groundings and 27 sunken ships, giving a total of 644 incidents since 2000. That's more than twice what the IMO data shows for cruise ships, ferries and other passenger vessels combined.

"No one keeps track of it and it's not really reported anywhere," Klein told Reuters. "I scour the world media every morning and look for what's been reported anywhere. I receive about 3,500 hits on my website every day, a lot of them are passengers and crew members and they send me information."

A presentation to The International Union of Marine Insurance's 2011 conference in Paris by Paul Hill, of marine consultancy Braemar (Incorporating The Salvage Association), indicated that the passenger shipping industry may be more accident prone than it cares to admit.

A table in Hill's presentation shows that passenger ships, including ferries, account for 9.9 percent of casualties at sea and just 6.3 percent of the global shipping fleet, meaning statistically they have the highest casualty rates of any type of shipping. Passenger shipping also accounts for 40 percent of the total cost of casualties at sea, the presentation shows.

Hill declined to speak to Reuters about his report's findings.

POWERLESS

The lack of global rules means there is little to stand in the way of the considerable autonomy that ships' captains have accumulated over the centuries and that there is nothing on a global level to prevent practices such as so-called showboating where ships sail close to shore to give tourists a better view.

Some inhabitants of the island of Giglio where the Costa Concordia now lies on its side, say they had been told beforehand that Captain Schettino would perform a salute which took the ship within 150 metres of the shore. Schettino is accused by prosecutors of multiple manslaughter, causing a shipwreck and abandoning ship before all the passengers were evacuated.

"There are no national or international rules that forbid ships steering close to shore," a spokesman for Italy's Coast Guard department which deals with maritime security told Reuters. "It's not that we knew about and allowed these salutes as you might suppose, it's that you can't really stop a ship from approaching within a minimum distance of the shore for tourism purposes."

The practice may have become common along the Italian coast. Enrico Scerni, former president of the Genoa-based RINA ship classification organisation, has said that it is difficult to believe Carnival's Costa Cruises division was unaware that captains often went close to Giglio to salute the island and give passengers a closer view. Schettino said Costa had told him to perform the manoeuvre but the company said it was unaware of risky approaches so close to the shore.

Many in the shipping industry have rejected the idea that "showboating" has become widespread, saying that captains should only depart from an agreed course when necessary.

"Sailing close to shore - for whatever reason other than for the safety of life, and especially not for entertaining passengers, crew or people ashore - is certainly not commonplace," said John Dalby, a former oil tanker captain who now runs Marine Risk Management. "The vast majority of masters, officers and owners are far too responsible to indulge in such potentially dangerous practice ... Neither do I know of any owners - including Carnival - who would advocate, propose, suggest or order such reckless, irresponsible actions."

Tracking data from shipping publication Lloyd's List has indicated not only that the Costa Concordia had already sailed within 230 metres of Giglio in August but also that it was the only large cruise vessel to sail so close to the island in the last six months, with others giving it a relatively wide birth as they sailed through the strait separating it from the mainland.

"The question is who authorised the order to go that close," said Mike Smith, a retired master mariner with 45 ship commands and over 34 years experience including as captain of a cruise liner. "There is always a temptation to get closer in to keep the passengers happy which is what the company wants the ship to do provided it remains safe."

He noted, however, that typically captains would err comfortably on the side of caution while others pointed out that for all the disagreements over how widespread or tacitly approved showboating had become, the high degree of autonomy enjoyed by captains brings with it a high degree of responsibility.

"Command of any ship means that the captain is ultimately responsible for all aspects of the ship's operations," said one senior shipping official who asked not to be named. "This is a necessary approach developed over hundreds of years of maritime trade and operations. The master operates autonomously within guidelines provided by the company, the flag and international regulation."

NO BLACK BOX

The official said the need for a ship's commander to make on the spot decisions meant it was important not to compare procedures with those of the airline industry. But for others the Costa Concordia affair has highlighted glaring differences.

"What needs to be done is the designated person ashore needs to be monitoring these ships all the time, and if they go off course they should get on the radio and ask 'why are you off course?'," said one senior marine underwriter at the Lloyd's of London insurance market.

"With aircraft, if you go 2,000 feet too high or too low, you have air traffic control on the radio immediately saying 'you're off course, get on course'. Maybe what they'll come up with is the equivalent of air traffic control for passenger ships."

Under IMO rules data recorders, known as black boxes, have been mandatory aboard passenger ships since 2004 but there is a get-out clause exempting ships built before July 2002 where it can be demonstrated that fitting one alongside existing equipment would be unreasonable or impracticable.

By contrast the flight data recorders have been widespread since the 1960s.

In the case of the Costa Concordia, Schettino has been quoted in the Italian press as saying the black box had been broken for two weeks and he had asked for it to be repaired, in vain.

The slow-moving nature of consensus-based global regulation means there is unlikely to be a revolution in the industry overnight but things are already starting to move on a local level.

CODE WORDS

The U.S. Congress, which over the years has resisted efforts to more closely regulate the cruise line industry, last week launched an investigation of industry safety practices with a hearing due next month, while Italian environmentalists and some politicians are demanding that big cruise ships be banned from passing too close to islands or shorelines, or entering environmentally delicate areas such as the Venice lagoon.

Vessel design changes may also follow the accident which has revealed how the problem of getting thousands of people off a cruise ship and into lifeboats quickly has still not been resolved 100 years after the Titanic disaster.

In some areas of ship safety, there have been suggestions that things have gone backwards in recent years as the cruise ship industry seeks to strike a balance between pressure to constantly refresh fleets with ever smarter vessels and making money. Most of the Costa Concordia's 1,023-strong crew were there to run the bars, swimming pools, theatres and casino rather than qualified seamen.

While entertainment and hospitality staff would have had training in emergency procedures, there have been questions over the quality of that training given that these days most of them will have been agency staff who came from around 40 different countries.

"On our ship it was really, really strict," one former waitress with Cunard prior to its takeover by Carnival in the 1990s told Reuters. "We had boat drill every single day, we practiced tying on people's lifejackets every single day. We had all these code words so passengers wouldn't panic - "niagara" was a flood, "starlight" meant somebody had died."

Some on the Costa Concordia have said they did not get a full safety briefing within 24 hours of boarding while a Reuters reporter who cruised on a sister ship of the Concordia last summer went nearly 36 hours without a briefing after boarding.

Carnival has defended its compliance with rules on safety drills but here, once again, there are grey areas. The Standards of Training, Certification and Watchkeeping Convention provides global guidelines on safety training for crew which were most recently amended in 2010 but the IMO has little authority to enforce those standards.

There has also been much debate around Schettino's decision to leave the ship before it had been evacuated but here too there are no rules governing a captain's behaviour.

"There is no basis in international law for the notion that the captain goes down with the ship, or that he is the last to leave the ship," said Vice Admiral Sir Alan Massey, chief executive of the UK Maritime and Coastguard Agency and a former senior Royal Navy officer. "There is more myth than reality to that notion."

Massey said that in certain circumstances, such as when communications systems go down on a stricken ship, it may be better for the captain to leave and to direct operations from another vessel.

The IMO has left the door open to reform, with Secretary-General Koji Sekimizu saying his organisation should seriously consider the lessons to be learnt.

"The frightening thing is how quickly the ship went on its side. If that had been out to sea there would have been a massive loss of life," the marine insurance underwriter said. "It's very similar to the Titanic disaster. The Titanic hit an iceberg and opened up like a can of sardines ... They will look at the disaster and there may be some changes, presumably vessel design changes."

(Additional reporting by Myles Neligan, Estelle Shirbon and Jonathan Saul in London; Ben Berkowitz in Boston; and Antonella Cinelli in Rome; Editing by Giles Elgood)

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