Information about injuries is normally derived from event reports. These may be required by maritime accident investigation authorities or by ship operators or their insurers. Case reports can be valuable if the case has been investigated in detail and the lessons from it identified. Maritime accident investigators in a number of countries produce such case reports, either as a result of their investigations into a major incident, or as summaries of the event reports they receive. Companies or insurers may do the same, although the latter often have more information about the financial consequences of an event than about causation, provided they have accepted to pay out.

The source data on injuries is heavily dependent on assiduous reporting by ship officers, with or without the prompting of crewmembers, or their safety representatives. There can be reasons, such as company incentive schemes for safety performance that encourage under-reporting. Also considerations about insurance or compensation may lead to miss-attribution of the cause of an injury to a non-controversial one rather than one that the ship operator could have to assume liability for. Individuals may also not report injuries for fear of criticism or losing their job.

 Academic investigators may sometimes mount studies of injury incidence and causation but most of the available data comes from official sources such as maritime authorities, with just the analysis undertaken as a science-based project. The pattern of reports is dependent on the criteria for inclusion, for instance which locations are covered, and the reporting criteria used: fatal, requiring hospital admission, unable to work for more that three days etc. Also measures of incidence need to be analysed separately from measures of the duration of incapacity. Incidence measures depend on reliable documentation of the population at risk; something which is difficult with mobile populations like seafarers or those - such as workers in fishing - who are self-employed and often only work a limited number of days a year.(1) These population measures need to be handled with caution as a seafarer will spend part of their day working and being exposed to one pattern of injury risks, another part also on board, and still adjacent to the workplace, and some time engaged in work tasks in port.

 Fatal accidents in merchant seafarers are the subject of statutory notification procedures in many countries and most investigations have used such information as the basis for their analysis. Probably the longest series of consistent analyses come from Britain, where the rate in merchant seafarers has dropped from 208 per 100,000 person years in 1921 to 11 per 100,000 in 1996-2005.(2) During this time ships, and hence risks, have changed hugely. Around 50% of fatalities in most studies arise from ship disasters.(3) There are large differences in reported fatality rates between countries, many of these are likely to be explained by different inclusion criteria for reporting, for instance whether fatalities while travelling to or from work are included. Fatality rates among seafarers are far higher than the average for onshore workers, sometimes as much as 10 times.(4)

 Studies of non-fatal injuries use data from a variety of sources, statutory notifications, insurance claims, company records. The downward trend is less clear than for fatal accidents, and most studies are essentially limited to personal injury records, excluding ship disasters.

 Ratings usually have a considerably higher incidence of injuries than officers.(5) As on land; slips, trips and falls are major causes of injury, with movement between ship and shore as a significant contributor.(6) Human factors, notable fatigue, are probably just as important antecedents to personal injuries as they are to ship disasters

 Injury rates are generally even higher in the fishing industry than in merchant seafarers. The industry uses a huge range of vessels, from large factory trawlers to dug out canoes. Each type of vessel and method of fish catching has its own pattern of injury risks.(7) These are also modified by factors such as weather, water temperature and the presence of harmful or predatory marine life. Fishing has been consistently shown to be among the highest risk of industries.

 Fatality rates in developed countries, mainly in NW Europe, where studies most studies have been conducted, have been reducing in recent decades.(8) Around half of all fatalities were attributable to vessel disasters. Some of these were a consequence of instability either from unsafe modifications or from fishing activities, but it is likely that human factors and especially fatigue, which is commonly at high levels in fishing crews, were major contributors.(10)

 Fish farming has its own pattern of injuries, some from the use of small boats and some from diving incidents.

 Risk management strategies can be shown to be effective. For example, in Alaska fatal accident rates have fallen from 4.2 per 1,000 person years in 1980-4(11) to 1.16 in 1991-8(12). During this period part of the fleet was renewed with larger and safer vessels. Better personal protection including immersion suits with radio beacons were also required.

 In recent years there have been important improvements to protective clothing for fishing with built in insulation and buoyancy and aids to casualty location.

 While data are available from a very limited number of countries there is no available evaluation of risks on the large number of almost certainly less safe boats in use in the developing world. But it is clear that fishing everywhere has a high risk of accidents and that there is considerable scope for better prevention, given the resources and will to intervene.

 

 The available studies show:

 - the high overall rates of injury compared with most other occupations, with fishing as the most extreme.

 - the contributions of vessel disasters, occupational injury and injury in non-occupational settings to the total.

 - the limited sources of the available data, with none from other than developed countries with established maritime regulation and academic centres

 - the problems of comparability because of different recording criteria

 - the lack of follow up studies to explore the consequences of injury for the persons affected, their rehabilitation and subsequent working ability.