Steel Worker is a reflex game that combines OH&S with the Japanese practice of just in time manufacturing. Each level starts with a mindless worker moving steadily from one side of the factory to the other along an incomplete gantry. To prevent the worker from falling to his doom, the player must select another piece of the gantry to be erected by the time the worker reaches the end of the current one. The process is repeated until the worker makes it to safety at the platform at the other end of the screen, or four workers have died. Complicating matters are a pair of elevators in the centre of the screen whose touch will be fatal to the steel worker.

There are five types of bridge that may be placed at any time: horizontal, slanting up, slanting down, staircase up and staircase down. A different selection needs to be made depending if the worker is moving left or right, giving a total of ten options. These are chosen using a cursor which can be moved left or right across the bottom of the screen and pressing the select button. There is also a reverse button which will turn the worker around, but this can only be performed a maximum of nine times in total. Points are awarded for adding parts of the gantry, and for the worker successfully crossing the screen.