He grew up in the Perth suburb of Thornlie and later on a 200 ha (500 acres) farming property in Gidgegannup; he attended Eastern Hills Senior High School in Mount Helena, near Gidgegannup.[5][6] A veterinary surgeon by profession, Challen has made notable dives in Cocklebiddy Cave and Pearse Resurgence.[7] In 2010 he made a record-setting 194 m (636 ft) dive while caving in New Zealand.[8] In 2020 he made a second record-setting return visit to the Pearse Resurgence (New Zealand) and extended the Australasian depth record to 245 m (804 ft) with his dive partner Richard Harris.[9]
^"Australian Honours"(PDF). Government Notices Gazette. Canberra: Commonwealth of Australia. 24 July 2018. ISSN0819-7105. Archived from the original(PDF) on 24 July 2018. Retrieved 25 July 2018.