More than 200 staff from the firm converged at Lynford Hall, Thetford, for the family day, when company cars and vans were exchanged for new vehicles.
Norfolk-based Briton Fire has switched from Godfrey Davis (Contract Hire) to Toomey Hire and Leasing as its contract hire supplier for new vehicles.
At the event, the firm took on 26 new Toyota Hiace vans, 16 Vauxhall Astravans and 16 Volkswagens, shared between Passats and Boras.
In a change of tradition, Briton Fire's new vehicles will be metallic silver, instead of red. The remainder of the 88-vehicle fleet will be changed over the next few months. Vans, replacing the current fleet of Toyotas, will be run on three-year/105,000-mile contracts, while cars, which are replacing Volvos, will operate on a three-year/90,000-mile arrangement.
The firm's managing director Mike Knight said: 'It is a company tradition that every three years we change over to a new fleet this way.
'We are a company with family values and believe it is important for staff and their families from our depots in Norfolk, West Yorkshire, Kent, Bristol and Falkirk to get together.'