A railing is a quest item in the Dwarf Cannon quest. Captain Lawgof gives the player 6 of them. With a hammer, they are used to repair damaged fence surrounding the Coal Trucks. There are 6 damaged areas along the fence, which can be found by inspecting every section of the fence to see if the second bar is bent. This will require camera rotation, as the bars are difficult to see from a high angle.
There is a chance to fail when repairing sections of the fence, and the player may receive small amounts of damage which will deal 1-2 Hitpoints. The player will also receive a message saying either "You cut your hand on the rusty old railing.", "You strain your back trying to handle the railings.", or "You accidentally crush your hand in the railing.".