Every vessel shall at all times…

'Every vessel shall at all times maintain a proper look-out by sight and hearing as well as by all available means appropriate in the prevailing circumstances and conditions so as to make a full appraisal of the situation and of the risk of collision.' So begins Rule 5 of the The International Regulations for Preventing Collisions at Sea, adopted by the International Maritime Organisation in 1972 and given legal force in the UK under the Merchant Shipping Regulations 1996. 

The rules (Colregs) are made available for free by the Maritime and Coastguard Agency to be learned by rote by anyone aspiring to take command of any vessel in a seaway, whether it be a 6-metre dayboat or a container ship. (My personal copy, with its rusty staples and faint smell of damp and paraffin, takes the form of a 64-page booklet priced at £2.50.) They are thorough, pedantic and leave no room for doubt or interpretation.

Rules 1-4 set out general principles of application, responsibility and definitions: 'Vessels shall be deemed to be in sight of one another only when one can be observed visually from the other.' The meat begins with Rule 5; it is followed by Rule 6, which begins 'Every vessel shall at all times proceed at a safe speed so that she can take proper and effective action to avoid collision and be stopped within a distance appropriate to the prevailing circumstances and conditions.'

Whether breaches of these rules caused the collision between the Solong and Stena Immaculate in the North Sea off the Humber Estuary on Monday morning we do not know. The full analysis will await the report of the Marine Accident Investigation Branch: an agency which, in the tradition of its aviation forebear, asserts that its reports are 'not written with ltiigation in mind' and are inadmissible 'in any judicial proceedings whose purpose, or one of whose purposes is to attribute or apportion liability or blame'. The arrest of a 59-year-old man on suspicion of gross negligence manslaughter must also curb speculation about potential criminal blame. 

What we do know is that the collision of two ships carrying hazardous cargo in a foggy busy anchorage is the kind of out-of-the-blue incident which changes rules. In the past, such disasters have been caused by combinations of mechanical defects, negligence by owners and incompetence on the bridge. Take the 1987 collision in the Philippines between the tanker Vector and the Ferry Dona Paz, in which some 4,400 people died. (Never heard of it? It remains the deadliest peacetime maritime disaster in history, but for British newspapers at the time it provided a handy way of filling an early foreign news page.) The tanker was found to be unseaworthy, with no-one on the bridge while the ferry was grossly overloaded and lacked lifesaving equipment and even a count of the number of souls on board.

Couldn't happen here? In that same year, the ferry the Herald of Free Enterprise capsised, with the loss of 193 lives, because of the 'tea tray' effect of water sloshing about because of bow doors negligently left open. And the following year the explosion on board the Piper Alpha oil and gas platform in the North Sea (167 dead) exposed a shocking culture of complacency in the running of a major industry. A key fallout from that disaster was the transfer of responsibility for offshore exploitation operations from the Department of Energy to the Health and Safety Executive. The fact that only one crewmember appears to have been lost in yesterday's collision and fires may be due to the safety regime involving standby safety vessels following Piper Alpha - on top of heroic work by an allegedly ill-equipped Royal National Lifeboat Institution crew.

For all this bitter experience, the sea remains a dangerous place. An unusual detail of yesterday's collision was that it occured between ships flying two respectable flags, Portugal and the USA, from which we should expect high standards of professional competence. Naturally the inquiry will look closely at any human failings that might have left no one on watch at the critical moment. 

Another factor is technology. Both ships would have been equipped wtih at least duplicate sets of radar on both the X-band and S-band frequencies as well as automatic identification transponders. But it was a sudden catastrophic power loss which seems to have caused last year's collision which destoyed the Francis Scott Key Bridge in Baltimore. Finally, given the nature of the Stena Immaculate's cargo and the fact that the world is teetering on the edge of undeclared cyberwar, the possibility of sabotage, crazy as it seems, cannot be ignored. 

That's enough speculation, for now. I'm off sailing at the weekend, I hope in a benign corner of the English Channel. I'll take with me a couple of quid extra for the lifeboat tin - and my old copy of the Colregs, too.

Michael Cross is the Gazette's news editor. He reported the Herald of Free Enterprise and Piper Alpha disasters for national newspapers.