W6 may refer to: Worcester Cold Storage Warehouse fire In the US the symbol W6 is often affixed to firefighter helmets and apparatus as a tribute to the Worcester 6; 6 firefighters who died in a warehouse fire in 1999 London W6, a postal district in London W6 class Melbourne tram, a class of electric tram that operates in Australia SSSR-V6 OSOAVIAKhIM, also referred to as W6 Ossoawiachim, an airship constructed in the Soviet Union IATA code for Wizz Air airline a particular width for a structura… (More on W6)