The IC class was converted from _I__ and _IA_ type wagons of both short and long underframe type.
The first IC's appeared in 1954. This may have been part of the electrification project to segregate brown coal traffic as a new electrified branch from Moe to the Yallourn opened in the same year.
By the 1970's, the IC traffic was Bacchus Marsh (Maddingley mine) and Fairfield with about 3-4 trains per week. The Yallourn IC traffic had stopped long ago. Briquette trains still ran to Newport Power station, though from the Morwell Briquette factory. Briquettes were originally planned for production with Morwell coal. However the coal was unsuitable and Yallourn coal was transferred to Morwell via the narrow gauge SEC railway.
There were three tipplers in the system: Newport Power Station; APM, Fairfield and the Heinz Co. plant at Dandenong whch was still working into the late 1990's before conversion to gas. The tippler was simply a large clamp that secured the wagon to a table. The table then rotated around to empty the wagon, then returned. Rotation involved uncoupling the wagon and placing it on the table. Axlebox oil levels needed to be checked after tippling to see if topping up was required.
Some conversions into the class involved other wagons with I / IA heritage.
All up, there were about 350 vehicles in this traffic between 1954 and late 1970's. For this traffic surplus open wagons had the doors welded closed or large steel plates placed across the door openings. Many of the conversions replaced wagons being removed from service.
The IC's were scrapped progressively from 1970 to 1978. There were some conversion to _HD_ for locomotive traction sand.