What U.S. courts will look for is an industry standard for safety, even if implicit, and then see if you are meeting or exceeding that standard.

In the U.S., for climbing gyms, part of the standard is a belay test. In the article, Mayfield talks about trying to get the industry self-regulating before the government steps in. This is basically how that works: industry founders or leaders establish some procedures for safety, prove them out over time, then insurance companies implicitly adopt them and everyone else follows.