US Nuke boat crews wear a dosimeter badge on the boat.
The Navy has plenty of info related to low-level exposure if they ever want to share it.
This study looks to be more concerned with the old A bomb tests. Warheads and reactors produce different kinds of contamination and vastly different amounts. I had some valves I was responsible for when I was on watch that were located on the reactor compartment's forward shield. If I was worried about getting contaminated, I'd rather hang out next to those valves than hang out in Las Vegas.