15 foot swells is way too much for me. Biggest swells I had to dive in was on the north side of Maui. I’m going to guess they were about 7 feet. It was pretty sketchy trying to get back in the boat at the end of the dives. We were the only boat I saw go out that day.
Imagine that being one of your first dives after training. It was wild to be able see out the side of the wave during the safety stop. Timing the ladder was the biggest problem on getting on board. Glad I did it before I turned 50.