A volunteer with the Strathmerton CFA (http://www.cfa.vic.gov.au/) has become a Captain at 24 years of age.
Full article at: http://www.cfaconnect.net.au/news/captain-at-24.html
I'm not sure how the rank structure compares to the US, but here, he is the Captain of the local volunteer brigade, and would be supported by a number of Lieutenants.
At 24 is it too young?
Does he have enough experiene in both life and the emergency services?