In 1976, Nadin joined the IIHF rules and referee committee, and was a referee supervisor at each Winter Olympic Games from 1976 until 2012. He travelled worldwide to assist, and evaluate officiating crews at IIHF events. He was responsible for writing, updating, and interpreting rules. Nadin said that, "the president of the ice hockey federation refers to me as the pope of the rules". He also conducted referee seminars in over 40 countries, and implemented regulations on ice hockey goaltending equipment at IIHF events. He was part of the committee which selected referees for the 1998 Winter Olympics in Nagano, and the 2006 Winter Olympics in Turin. He also supervised officials at the 2011 Asian Winter Games, the 2012 Winter Youth Olympics, the 2013 IIHF World Women's U18 Championship – Division I, the 2013 IIHF World U18 Championships, and the 2017 Asian Winter Games.