Working at a university has many benefits. One of them is that you get access to international standardization documents. And I managed to dig up a copy of "EN 13814: Fairground and amusement park machinery and structures, Safety". It actually doesn't require a specific number of hours of testing (or number of cycles, for that matter), but it does require a whole lot of different load combinations to be tested before the ride is allowed to open. Maybe local laws have time requirements before the ride is approved, but I really doubt it. After all, how much testing you get out of, say, 1000 hours depends entirely on the ride's cycle time.