HME Go-Line/ Park-Ups. A Clear and Present Danger?

Over the years I have published many articles here on Linkedin, many of which related to poor understanding and management surrounding lightning related safety issues across higher risk industry sectors.

I would hope my posts will have highlighted to high risk sectors, that despite the best intentions, significant lightning related incidents still continue to occur, and that should dictate that 'risk re-assessments" be undertaken, where additional controls be investigated that would then address those evident gaps, and then appropriately deal with what are undiagnosed risk issues.

The recent injuries associated with a lightning initiated HME tyre pyrolysis, and tyre explosion at a Qld Coal Mine in Dec 2020, highlights yet another undiagnosed and potentially fatal risk, which I suggest may affect the majority of mining operations across Australia.

So the real question everyone should be asking is how can it be that two (2) workers situated within a so called 'safe shelter' could be injured from a lightning related incident?

HME tyre pyrolysis and tyre explosions have been a regular visitor to Australian and overseas mining operations in recent years, with several overseas incidents having proved to be fatal. Given the significant event last month, Australia now has 'skin in the game'.

Industry regulators are well aware of the pyrolysis risks associated with large rubber tyred HME, as are the resource companies themselves, who usually provide administrative hierarchal controls, that include;

• the development of Lightning Management Plans,
• the development of TARP,
• establishing tyre fire exclusion areas.

which all help address the issue, however it is the authors view, having visited over 100 remote mining operations, that the initial engineering and design aspects associated with the proximity, and orientation of HME go lines/park-ups to sensitive areas, is simply not catered to within mine design, and then later within Lightning Management Plans, and here lies the crux of what I perceive as an undiagnosed significant risk.

It is this authors view that very little consideration has ever been afforded to the potentially lethal debris radius, or pressure wave zone associated with a HME tyre explosion, and which typically surrounds a HME parked up at a go line/ park up area, in any event of a tyre explosion.

Recent significant tyre explosions (lightning initiated) had resulted in;

• A 1600 kg wheel assembly being ejected approx. 100 mtr's away from the truck.
• A 250 kg wheel flange being blown off landing on a stockpile some 300 mtr's away
• Window glass within nearby buildings shattered from around 230 mtrs away.

Given the perceived lack of proximity oversight, such a revelation should be vigorously taken up by the Australian mining sector, that they:

Investigate Go Line/ Park Up debris radius with regards to any close proximity to sensitive areas that include:

• crib huts,
• workshops,
• administration buildings
• refueling areas
• process plant
• major trafficable thoroughfares

Investigate all and any sensitive areas that may have any nearby exposure facing the side walls of large rubber tyred HME equipment at Go Line and park-up areas.

• what structures and populated work areas are facing the sidewalls of the tyres and are within the danger zone of any unintended pressure release.
• what operating corridors, haul roads, and general traffic areas are within the danger zone of any unintended pressure release.

The proximity and orientation of HME Go lines and park-ups need to be re-considered, as in many instances; crib huts, maintenance workshops, and admin structures, will be well within the debris zone and pressure wave of an exploding tyre.

Any lightning management plan MUST consider these, along with other related issues, that would cater to the unintended consequence associated with the random ejection of debris and massive pressure release upon nearby sensitive areas.

Image courtesy of Lightningman Pty Ltd Copyright

The above graphic highlights a recommended control which we suggest should form a mandatory design consideration within any go line/park up area, and simply involves the provision of freestanding lightning protection masts that provide a protective area coverage to HME, that would then sufficiently offer area protection to the go line/ park up areas, and thereby reduce the probability that any negative event could lead to unnecessary consequences.

The current Australian lightning protection standard AS1768 is currently in revision, to which a new Appendix M is to be a new inclusion that we understand will specifically cater to lightning risks on mines.

We understand that the issue of large rubber tyre pyrolysis and tire explosions forms an integral aspect of this new Appendix M.

Lightningman Pty Ltd have been applying similar area protection systems to Go lines, ROM, Accommodation Villages, and other sensitive areas for over 18 years.

We are specialist in lightning related risks to high risk industry sectors and can advise, design, and supply the correct risk mitigation solutions.

Grant Kirkby- Lightningman