Active Advanced Warnings Signs (AAWS) should be used in advance of traffic signals where sight distance to signals or a potential back-of-queue is limited. They are also used in locations where drivers have a lowered expectation of signals, for example, when driving from a rural to a built-up area. The process to determine the longitudinal placement of AAWS is related to the availability of stopping sight distance and is given in AS1742.14. 

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