During face loadout operation at a hard rock quarry, a large piece of stone (weighing approximately 6 tonnes) toppled a short distance from the side of the blast-pile and struck the nearside of a CAT 390 excavator, causing damage to the machine’s retractable access steps. No one was hurt in the incident.  

Key Findings

•            Although there was a suitable rock trap in front of the machine the rock trap at the nearside of the machine was not sufficient to contain the piece of rock.

•            The excavator operator was very experienced and fully qualified having had formal face excavator and geotechnical training – he had operated front line face machinery for many years.

• In accordance with QNJAC guidance, operators must ensure that; “there is a suitably designed rock trap in place, which as a rule of thumb should be ? of the face height in depth and ¼ of the face height in width” to capture and contain any rocks that fall from the face / blast pile during load out.


• The task specific E&T job cards are to be reviewed and reissued to all face operatives, along with re-training, to ensure safe working requirements are clearly understood and complied with at all times.


• If you are unable to comply with standard safe working practices ‘STOP THE JOB’ and speak to your supervisor or line manager to discuss and review the safest way forward.  


• You could led a Team Discussion (remember to involve colleagues, regular contractors and hauliers in your discussion) - Could a similar incident happen on our site and if so, what are we going to do to make sure it doesn’t?