In Europe, falls under the F-Gas directive which ban or control its use for several applications. Since 1 January 2006, is banned as a tracer gas and in all applications except high-voltage switchgear. It was reported in 2013 that a three-year effort by the United States Department of Energy to identify and fix leaks at its laboratories in the United States such as the Princeton Plasma Physics Laboratory, where the gas is used as a high voltage insulator, had been productive, cutting annual leaks by . This was done by comparing purchases with inventory, assuming the difference was leaked, then locating and fixing the leaks.