Mineral Mines & Quarries Inspectorate | Alert | No.421 V 1 | 16 December 2022

Tyre explosion on rear dump truck following lightning strike

What happened?

A short but significant storm passed across a mine during day shift operations. Surface trucking operations were halted and operators were instructed to park machines. Personnel were transported to crib and office facilities until the storm passed.

Upon returning to the parking areas to resume operations, workers discovered the tyres (positions 3, 4 and 5) on a rear dump truck had exploded. The explosion caused tyre fragments to project into the general park up area and nearby mine road, and a rock ejector was found approximately 10 metres away from the machine.

How did it happen?

It is believed a lightning strike during the storm caused internal pyrolysis on the tyres leading to the explosions.

Key issues

• Lightning
• Severe weather
• Emergency response procedures

Recommendations

Mines should:

• review site adverse/inclement weather Trigger Action Response Plans (TARPs) and procedures to ensure effective controls are in place to manage lightning strike hazards for mobile equipment:
• consider a risk-based lightning management plan as per appendix M of AS 1768 : 2021
• ensure all workers exposed to the hazards associated with adverse or severe weather are trained in the relevant TARPs and procedures.
• assess the most appropriate methods of protecting workers from the consequences of tyre explosions, including appropriate methods of preventing lightning strikes to mobile plant at park up locations.
• recognise that rubber tyred mobile plant cannot be considered as a place of safety during a lightning storm. Care must be taken where these vehicles are parked during a lightning storm so as not to create a hazard for persons, buildings or structures.
• ensure appropriate emergency procedures are in place for managing tyres involved in lightning strike events and hot tyres.

References and further information

A number of safety notices have been published regarding adverse weather and lightning strikes, including the following:

• Safety Bulletin 207 'Managing the risks of storm season' published 7 December 2022.
• Safety Bulletin 205 'Risk management during lightning events' published 7 October 2022.
• Safety Alert 383 'Tyre explosion following lightning strike' published 23 December 2020.
• Safety Bulletin 176 'Lightning strikes on rubber-tyred vehicles' published 27 November 2018.