A HiPo near miss occurred when interlocks were used as a form of isolation.
During aggregate processing, a blockage occurred within the chute under the secondary screen. To clear the blockage access to the area protected by distance guarding was required. The dedicated isolation point for the screen belt was not utilised, instead the interlock located on the access gate of the distance guard was relied on for the isolation, this was against the agreed SSOW and training.
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