Quarantine "yellow jack" but this was also a name for yellow fever, which probably derives its common name from the flag, not the color of the victims (cholera ships also used a yellow flag). The plain yellow flag ("Quebec" or Q in international maritime signal flags) probably derives its letter symbol for its initial use in "quarantine", but this flag in modern times indicates the opposite—a ship that declares itself free of quarantinable disease, and requests boarding and routine port inspection. Australia has perhaps the world's strictest quarantine standards. Quarantine in northern Australia is important because of its proximity to South-east
Flag of Northern Ireland to show their support for a United Ireland. After the 1998 Good Friday Agreement, flags continue to be a source of disagreement in Northern Ireland. The Agreement states that: Nationalists pointed to this to argue that the use of the Union Flag for official purposes should be restricted, or that the Irish tricolour should be flown alongside the British flag on government buildings. Sinn Féin ministers in the power-sharing Northern Ireland Executive instructed that the Union Flag was not to fly from buildings operated by their respective departments. This power was removed from ministers by virtue of the Flag Regulations