The deaths of three crewmen on board a rig support vessel have once again highlighted the dangers of work in the offshore oil and gas industry.
December's Morecambe Bay crash killed seven people
It is less than four months since seven men died when a helicopter ferrying workers between gas rigs in Morecambe Bay, Lancashire, crashed into the Irish Sea.
A fortnight later, two gas production platforms off the coast of Lincolnshire came close to being hit by a cargo ship which had lost power and was drifting out of control in bad weather.
2006/07 No fatalities, 7 major injuries
2005/06 One fatality, 28 major injuries
2004/05 No fatalities, 27 serious injuries
Source: HSE (Does not include helicopter casualties)
According to the Health and Safety Executive, more than 20,000 people are employed in the offshore industry in the UK.
It says there have been major improvements in safety standards since the Piper Alpha disaster in July 1988, when a blaze on the North Sea oil platform killed 167 of its 226 workers.
"The statistics are a very good story, the way we've brought down injury figures," said Tom McLaren, operations manager with the offshore division of the HSE.
But the watchdog says fires, explosions and structural failures of the platforms remain ever-present risks with "the potential to cause major loss of life".
Human cost of oil
1980: Alexander Kielland platform capsizes with loss of 123 lives
1986: Chinook helicopter crashes into North Sea killing 45 workers and aircrew
1988: Explosion and resulting fire on Piper Alpha platform claims 167 lives
Just this year, the HSE warned that an increasing number of the floating rigs were now beyond their planned life by as much as 10 years.
While there was no question that they were in danger, they were needing increasingly regular maintenance, it said.
"There are long term issues," said Mr McLaren.
"There are bottlenecks in finding qualified personnel to do the work that's required, and the lead-in time for getting some of the equipment that's needed is also problem."
There are also concerns that the industry is facing increasingly tough times, with the cost of extracting the gas and oil left beneath British waters rising as reserves begin to run down.
Professor Mick Bloor of the University of Glasgow, who has studied the industry, described the North Sea oil rig support vessels as being "the quality end of the shipping industry."
But a study he was involved in found the dangers of work at sea were made worse by the long hours and irregular working hours of those in the offshore industry.
"That has implications for getting proper sleep and leads to the possibility of fatigue-related problems in what is an already demanding environment," he explained.
The industry has set itself a target of being the safest offshore sector in the world by 2010, and the Offshore Operators' Association says the number of safety incidents fell in the last quarter for which figures are available.
But earlier this month officials with the union Amicus pointed to an HSE report into accidents involving cranes as showing that operators were paying no more than lip service to concerns about safety.
Officials from the executive issued nine enforcement notices and made 173 written requests for action after carrying out checks on 70 platforms.
Graham Tran, the union's regional secretary said: "Amicus has been saying time and time again that safety must be a number one priority, but it appears to fall on deaf ears.
"The industry is not learning lessons and is paying lip-service to the safety and well-being of the workforce."