Fail safing human factors

Industrial equipment design must include safe methods to allow access for either maintenance or operational intervention. The removal of motive electrical power from a machine prior to operator intervention is a process that includes actions to stop the machine, remove motive power, establish personal control (lockout) of the device that has been used to remove the motive power, and verify that the motive power has been removed. This article demonstrates some of the problems encountered using traditional methods to disconnect the power from an industrial machine. A developmental concept has been proposed that is being used in newer designs to disconnect electrical power.