In June 2012, the World Health Organisation (WHO) released findings that classed diesel exhaust emissions as carcinogenic (capable of causing cancer) to humans, to the same extent as cigarette smoke and asbestos. The underground mining industry now faces its most significant challenge yet: eliminating the deadly threat of diesel particulate matter, emitted from plant, machinery and light vehicles in the confined underground environment.

The WHO investigation exposed for the first time the stark reality of this danger, based on sufficient evidence that sustained exposure to diesel is associated with an increased risk for lung cancer, particularly among underground miners.


The WHO’s week-long summit of international experts, in conjunction with the International Agency for Research on Cancer (IARC), produced these key discoveries:

  • “In March 2012… a large US National Cancer Institute/National Institute for Occupational Safety and Health study of occupational exposure to such emissions in underground miners…showed an increased risk of death from lung cancer in exposed workers.”
  • “It was concluded that there was sufficient evidence in humans for the carcinogenicity of diesel exhaust”
  • “The Working Group found that diesel exhaust is a cause of lung cancer (sufficient evidence) and also noted a positive association (limited evidence) with an increased risk of bladder cancer.”
  • “Standards drive technology and new technology enables more stringent standards. For diesel engines, this required…reductions in emissions through exhaust control technology. However, while the amount of particulates and chemicals are reduced with these changes, it is not yet clear how the changes may translate into altered health effects…In addition, existing vehicles without these modifications will take many years to be replaced.”

In summary – emissions from diesel engines in vehicles and machinery are a life-threatening hazard to Workplace Health and Safety in the underground mining space. So what can be done to cleanse the air, protect the livelihoods of mining workers and sustain the future of one of Australia’s largest industries?

Diesel Particulate Filters (DPFs) are one popular option. These devices are fitted to light vehicles to physically capture diesel particulates from the exhaust, preventing their release to the atmosphere. However, while these can trap ‘heavy’ solid particulates such as carbon (soot), DPFs can be totally ineffective in controlling the extremely small or gaseous portions of emissions, known as ‘fine’ particulates. These fine particles, include toxic substances such as sulfur and are a more likely cause of death than the solid matter collected in the DPF – a major problem that cannot be solved with existing diesel-fuelled vehicles.

As the existing technology used to limit diesel emissions underground fails to prevent the most dangerous of particles entering the underground air, there is only one solution to eliminate 100% of diesel emissions.

That solution is the Voltra eCruiser. A paradigm shift for the mining industry, and one which is urgently required.

We’ve upgraded the traditional Toyota LandCruiser 79 Series to create the first suitable ‘fit for purpose’ mining vehicle for the industry. The Voltra conversion kit is fitted to existing vehicles to minimise the impact on fleet availability.

  1. 100% Battery Electric Drive – Zero emissions produced underground, and if powered from a renewable energy source, zero impact on the finite resource of fossil fuels.
  2. Elimination of complex automotive diesel mechanical systems, replaced with comparatively simple electric systems
  3. Designed for fast and easy deployment underground, key features enabling this are:
    • The battery pack – while relative low energy density compared to what is available, presents the lowest risk of fire – far less than the risk presented by traditional diesel powered vehicles
    • Based on the Toyota LandCruiser, the vehicle the industry is already familiar with
    • Remote monitoring to ensure issues are quickly identified and resolved, providing for the fastest possible design iterations and therefore the best ‘fit for purpose’ product
    •  Support to existing service providers to help develop the support expertise needed



By deploying the VOLTRA across an entire mining fleet, all carcinogenic emissions are removed from the underground environment, as well as reduced cost of mine environmental management, improved fleet utilisation, and improved safety. But the industry must show support the project to achieve the product refinement and cost reduction needed to implement it across the nation, and make a positive difference for environmental sustainability.



Efficiency. Innovation. Zero Emissions.