Australian Road Rules
The Australian Road Rules define a bus lane as: a marked lane, or the part of a marked lane:(a) beginning at a bus lane sign (whether or not there is also a bus lane road marking) and ending at the nearest of the following:
(i) an end bus lane sign;
(ii) a traffic sign that indicates the beginning of another special purpose lane; or
(b) beginning at a bus lane road marking (if there is no bus lane sign) and ending at the next intersection.