An Australian Federal Police check is primarily used for Visa, immigration and citizenship purposes. It is used for applicants who live outside of Australia, and also overseas adoption purposes. In addition, if you are employed in Australian Commonwealth facilities or work in the Australian Capital Territory (ACT), Jervis Bay Territory or external Commonwealth territories, a Federal Police check is needed.
For all other purposes an Australian national police check or as formally known a Nationally Coordinated Criminal History Check is acceptable throughout Australia. In most cases employers seek a national police check for volunteer and employment purposes.