Machine guard distance

Machine guard opening/distance-to-point-of-operation measuring tool/stick (these are available from many machine safeguarding suppliers/consultants)... 

A form of distance guard whereby access to the area of hazard of the machine is prevented since materials are passed into the machine via a metal enclosure or tunnel. It is commonly used on metal cutting machines and usually incorporates an interlock, so if the tunnel guard is raised the machine stops operating. 

Safeguards include guards, devices, distance, or location. Safeguards for machines fall into two major groups mechanical power transmission safeguards, and point-of-operation safeguards. 

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