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 New Zealand use of the flag. No permission is needed to fly the flag, and it may be flown on every day of the year—government and public buildings with flagpoles are especially encouraged to fly the flag during working hours. However, it should never be flown in a dilapidated condition. Unlike some other countries there is no single official Flag Day in New Zealand, and no pledge of allegiance to the flag. Flag flying may be encouraged on certain commemorative days, at the discretion of the Minister for Arts, Culture and Heritage. The flag can only be used as a vehicle flag