The Rail Heritage Trust of New Zealand is spending about $70,000 on a new fire protection system, including sprinklers, inside the station.
Work on the new fire system began two weeks ago and was expected to be completed later this week, trustee Euan McQueen said.
The work was part of a wider refurbishment of the station and signal box, begun more than a decade ago.
The trust, which owns both buildings, was already beginning to plan the restoration of the station's interior, much of which remained in close-to-original condition, Mr McQueen said.
Both the station and signal box - which was refurbished in 2001 - were ''rare survivors of their kind'', he said.
The station opened in 1914 and was a busy stop for passengers commuting to work in Dunedin, freight and special trains delivering passengers to race meetings at the nearby Wingatui Raceway.
At its peak, 17 return services stopped at the station each day, but competition from bus services and increasing car use meant only a small number of people were using the station when it closed in the mid-1980s.
The station was the only surviving specifically suburban station on the former Port Chalmers and Mosgiel suburban train routes, Mr McQueen said.
The signal box was one of only four boxes still on, or close, to their original sites over the whole network - down from about 150 in use in the mid-1950s.
The trust hoped to restore the station's interior to how it was in the 1950s, which was ''probably the period of greatest use'', Mr McQueen said.
However, any opportunities for ''adaptive re-use'' would be considered, which could see a cafe, specialty shop or
other tenant in the building. That would mean more opportunities for the public to see inside and provide revenue for maintenance, he said.
The wider refurbishment had to date cost about $280,000. The cost of the interior work was not yet known, and was yet to be raised, with the hope design work would be completed by the end of the year, and improvements by the end of next year.
