Nzoungou, 24, was forced to bring an end to his seven-year playing career due to a string of injury problems.
The former prop has since spent 15 weeks training to kick off his new career as a firefighter and is now set to join the Cheshire Fire and Rescue Service.
Nzoungou said he wanted to pursue this career path as he wants to "feel part of a team" - emulating his time spent in rugby league.
"My last two years in rugby was the hardest part as that's when I started picking up the injuries," he said via the BBC.
"After I snapped my Achilles, I just said that was enough.
"I'm so happy I have (become a firefighter)," he added.
"The fire service does a brilliant job helping people and I wanted to be part of that."
Nzoungou's rugby league career started at St Helens before spending time with Melbourne Storm in Australia, Toulouse Olympique in France and Salford Red Devils.
He endured loans at Oldham, Whitehaven and Swinton before joining Hull FC in 2018.
A loan to Doncaster followed and then moves to Albi Tigers, Bradford Bulls and most recently Widnes Vikings before his retirement.
