During 1989, I did some dives at Guinas and Otjikoto lakes in the then called South West Africa (It is now called Namibia). These lakes are up north in Namibia close to a town called Tsumeb. At that time I was doing military service and our Sergeant Major was part of a diving team attempting a record breaking deep dive in Guinas lake. Four of us were granted leave to assist in that attempt. Well, our jobs were to set up camp and to do all dirty work.
My other job (I've been diving since 1984) was to dive down to the record breaking divers, during their deco stops, and assist the support divers during their filming. My task was to hold the spotlight to insure sufficient light during the filming period. The spotlight was actually powered by a surface generator. Remember, in those days technology wasn't what it is today regarding underwater cameras, etc!!
To make a long story short, one of the record attempt divers was a smoker. The 2 divers had to do about 6 hours of deco stops, and the smoker was really craving for a cigarette. We took a packet of cigarettes and a lighter down to him on his last leg of deco stops. He didn't think that was funny and showed us a few more hand signals that is not really applicable during diving. After surfacing and after he had a few puffs on his cigarette we had a good laugh though.
In any event the record divers were Boetie Scheun and Eben Benade. They were based in Windhoek, Namibia at that time and broke the South West Africa depth record. They did 130 meters (426 feet) that day!! It shows that even smokers can do it deeper.