When we did it, they’d make an announcement when we showed up for morning muster (Navy). You weren’t allowed to leave till you peed. We would literally have to stay in an area drinking water till it happened. Weren’t allowed to go work till we did, couldn’t have contact with our buddies who already did and we’re allowed to leave. Only knew about 2 people, not in my department, who failed in my three years on my boat. Know people smoked or did limes now and again, but don’t think it was a huge problem. Think it was just precautions so it didn’t become a problem as they probably learned their lesson about being lax early on.