Abstract: Known traffic barriers require heavy duty motors to raise and lower the arm. Accordingly, a traffic barrier arm operating mechanism comprises a component for raising and lowering an arm connected to a drive shaft. A crank arm is mounted on the drive shaft and a draw rod is connected to the crank arm, the draw rod passing through a bearing in which it is slidably pivoted. A spring guide is mounted at the bearing, the draw rod extending into the spring guide. The end of the draw rod remote from the crank arm carries a spring compression element engaging one or more springs contained within the spring guide and is arranged to compress the or each spring within the spring guide on rotation of the drive shaft in the first direction which, in use, causes the barrier arm to be lowered.