I occasionally did contract maintenance welding for concrete block plants and was sometimes required to crawl into and among the parts that could move to make necessary repairs...
I carried my own safety placards and padlocks, painted bright red and nobody else ever had the key...Used to placard, shut down and lock off the power box then verify power off to all related machinery personally before ever entering the work area...
Never did trust a switch and red tag alone...Some knucklehead might just come along and wonder “why isn’t this machine running?”, and restore power...
Human body versus machinery, the machine wins every time...