His NHL officiating career began in 1969 and included 19 Stanley Cup Finals. In 1984, he became the first NHL on-ice official to wear a helmet; four years later, the NHL later made helmets mandatory for all on-ice officials (however, any official who was not wearing a helmet at the time of the ruling could continue to go helmetless if they so desired). Subsequently, several officials followed his lead and beginning with the 2006–07 NHL season, all NHL on-ice officials were compelled to wear helmets. He also officiated 1,557 regular season games and 227 playoff games. Van Hellemond has been the NHL's #1 referee 14 consecutive times. He also officiated in two All-Star games, the 1979 Challenge Cup, and Rendez-vous '87.