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Interlocking Guards


               Interlocked guards work by cutting power to the
               machine when the guard is opened. They are a good
               guard to use when a machine needs to be accessed
               often.  An interlocked guard may use electrical.
               mechanical, hydraulic, or pneumatic power or any
               combination of these.

               Interlocking guard which has a movable part so
               connected with the machinery controls that:


               •  the parts of the machinery causing danger cannot
                  be set in motion until the guard is closed.

               •  the power is switched off and the motion braked before the guard can be opened sufficiently
                  to allow access to the dangerous parts.
               •  access to the danger point or area is denied while the danger exists.

                                Advantages                                   Limitations

                •   connected to machine controls, hence     •   required careful adjustments and
                    machine does not operate when a guard        maintenance.
                    remain open.                             •   do not assume that they are reliable.
                •   easy for frequent access.                •   difficult to do inspection or testing.
                •   any failure or loss of power does not    •   gate system can be easily by-passed by
                    expose people to danger.                     stepping inside the gate.




               Adjustable and Self-Adjusting Guards


               Adjustable guards are made up of a fixed guard with
               adjustable elements that are moved to suit each task.


               They can be:

               •  self-adjusting – guards that are forced open by the entry
                  of work

               •  distance guards – barriers that can be moved to a safe
                  distance from the danger zone.











                 POSHE V2 |                                                                                                                                                       Unit IG2 – Element 9 – Work   15
                  Equipment
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