I am not a lawyer, and this is not official legal advice. In addition, laws vary between countries, so the situation can always be different for your country or the country you’re diving in.
A while back, I attempted to answer this question about getting sued for not helping divers. Mainly this applies to professionals, who are trained to assist divers in distress.
The question was prompted by dive professionals (divemasters, instructors, etc.) who go on vacation, and when asked in a dive shop flash their advanced open water certification cards---not letting the shop know they have more training. The thinking is that when I am on vacation I don’t want to worry about other divers, and especially don’t want to get sued for not helping.
I asked around, and apparently there is no precedent for this. Unless you’re an employee of the dive operation, simply being there does not place a burden of responsibility on you.
Reader Steven pointed out an exception in some countries, like in the U.K. If you are a diver’s buddy, and they get into trouble, a “duty of care” kicks in and you are responsible to assist them to the limits of your training.
Even if you don’t reveal your true certification level, if an accident occurs with your dive buddy, the shop (or the family’s legal council) will look into it and discover whether you acted to the limits of your training.
As an open water or even an advanced open water diver, simply saying “the situation was too dangerous so I went for help” is a valid excuse, since your limits of training are not very high. However, as a rescue diver, divemaster, or instructor, you are explicitly trained for these situations, so you better be prepared to help.
Again, this only applies in certain countries, so check on your diving region. And it only applies to your buddy---you are not responsible for everyone in the water.
Thanks again to Steven for the additional information.
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