Australia Disability Standards for Accessible Public Transport 2002 9.1: Allocated space dimensions: 800 by 1300 mm per wheelchair to clause 6.1 of AS 1428.2 (1992), 1500 mm unobstructed height with only grabrails, request devices, overhead handrails and excursion barriers projecting, at least one space in every accessible taxi with 1410 mm head room (1500 mm for taxis entering service from 1 January 2013), and a contrasting sign beside each space stating it is priority for a mobility aid user and must be vacated

What does 9.1 require?

The minimum allocated space for a single wheelchair or similar mobility aid is 800 mm by 1300 mm in accordance with clause 6.1 of AS 1428.2 (1992), on all conveyances other than dedicated school buses and small aircraft and in premises and infrastructure. On conveyances other than dedicated school buses, small aircraft and taxis the space must be clear for 1500 mm above its floor and only a grabrail, a boarding device request signal, overhead handrails or handgrips, or an excursion barrier complying with AS/NZS ISO 10865.1 (2015) may project into it. Every accessible taxi must have at least one allocated space with minimum head room of 1410 mm, or 1500 mm for a taxi entering service on or after 1 January 2013. On buses (other than dedicated school buses), ferries, trains, trams and light rail a sign immediately beside or as close as possible to each allocated space, with at least 30% colour and luminance contrast against its background, must make clear that the space is provided as a priority for a person with a mobility aid and must be vacated if such a person needs it.