Travel insurers will normally cover jet-skiers themselves for injury or loss of, say, their watch when they take a tumble. But the vast majority of policies will not cover jet-skiers for injury to other people or damage to whatever they collide with. Furthermore, insurance experts say few if any companies will offer it as an add-on, even where they have an "adventurous sports" upgrade, and in many cases cover will not be available abroad.
Without such third-party liability cover, jet-skiers could face compensation bills of up to hundreds of thousands of pounds for crashes they are responsible for.
Of 15 travel insurers contacted by the Independent on Sunday only one - Columbus - has a policy that offers third-party liability cover for people going jet-skiing; the others exclude it. Most insurers lump jet- skis in with a standard exclusion they have for "motorised vehicles" (land or waterborne). Many see the combination of most jet-skiing being done on rented bikes, in many cases by people with little experience, and the fact that the bikes are powered as putting jet-skiing in a different category to most other beach-based activities. As one insurer puts it: "It's all kids beered up to the eyeballs. It's a silly risk to take on."
Insurers admit that in most cases this means jet-skiers will not be insured at all for third-party damage. People renting on a faraway beach are unlikely to be required to take out, or even be offered, insurance. Anecdotal reports suggest that some rental firms ask holidaymakers to sign a waiver that they already have liability insurance, although the reality is jet-skiers will almost certainly not have third-party cover under any other existing policy.
If the jet-skis are provided through a tour operator then that company may have some cover, and equally some reputable rental firms may have insurance. But a spokesman for the Association of British Insurers says: "The short answer is to be careful."
Certainly there is little indication that holidaymakers are aware of the financial risks they are taking with what is an increasingly popular holiday pastime. Over 50 per cent of holidaymakers surveyed recently by Columbus Travel Insurance said they had no idea if jet-skiing or other "hazardous" sports they had tried were covered by their travel insurance policy.
Columbus was the only insurer uncovered in our research to confirm that it offered third-party liability cover for jet-skiers. But, bizarrely, the same policy excludes liability cover for windsurfers, which most people would regard as less dangerous. The insurer says the difference probably reflects a bad claims history with windsurfers.
Our research also highlighted travel insurers' different attitudes to adventurous activities generally. Most give personal cover (as opposed to liability) for jet-skiers as standard, although one of the most recent entrants to the market - Direct Line, which includes Tesco's new policies - can be more restrictive. But fewer than half of insurers offer personal cover for bungee jumping as standard.
Where possible, therefore, the advice for holidaymakers thinking they might try adventurous activities is to check whether a chosen travel policy includes them, or whether they can be included at reasonable cost - before they go. Where there are exclusions that cannot be overcome - such as with third-party liability for jet-skiers - holidaymakers would be well advised to try to find a rental company with insurance.
q Research by Louise Hancock.