The NSW Resources Regulator recently issued a safety alert following an incident in which a workbox detached and fell two metres from an integrated tool carrier.
The work box hit the ground and rolled 90 degrees onto its side, and two mine workers located in the work box, were partially ejected from the work box and suffered minor injuries.
The incident, which occurred on 9 January 2021, occurred when two workers were tasked with installing a secondary vent fan from the roof in the main decline of an underground metalliferous mine using an integrated tool carrier and combination fan lifting/work box.
The work box, with fan restrained, had been attached to the integrated tool carrier during the previous shift and parked in a nearby adjacent heading ready for the commencement of work. In line with the requirements of a prestart inspection, the operator believed he had confirmed engagement of the attachment locking pins by lifting the work box from the ground and tilting it forward. He did not visually inspect the locking pins to ensure they had fully engaged the work box attachment.
The hydraulic isolation valve was placed in the isolated position and all three workers placed personal isolation locks to stop any inadvertent operation of the locking pins during operation.
The fan was raised and secured to the roof before the work box was partially lowered. During this lowering, the work box detached from the integrated tool carrier and fell to the ground. Upon hitting the ground, the work box rolled 90 degrees onto its side, ejecting the two workers.
An inspector from the NSW Resources Regulator attended the site on the day of the incident and conducted an assessment which identified the following contributing factors:
The alert recommended mine operators review their safety management systems, particularly focusing on ensuring that: