The Dayton Gems were a minor league ice hockey team based in Dayton, Ohio, and members of the International Hockey League from 1964 to 1977, and 1979–1980. In the fall of 1964 the lobby of their new arena, Hara Arena, had a natural gas explosion. The damage was minor and the expansion team was assembled from various cast-offs and young players looking for their first break in minor league hockey. Other teams in the league copied the uniform styling of the Gems. The Dayton Gems were the first adult team in North America to make helmets mandatory, long before the NHL adopted them.