Moving machinery is the second highest cause of fatalities in South African mines after falls of ground, making the implementation of effective proximity detection systems (PDS) a crucial step, but there are still perceived grey areas in mine safety regulations.

According to Anton Lourens, managing director of leading PDS supplier Booyco Electronics, the Department of Mineral Resources has laid the groundwork for the wider application of PDS through the February 2015 amendment to Chapter 8 of the Mines Health and Safety Act (MHSA). It is now required that PDS be installed on all mobile equipment on mines.

“Mines are required to assess significant risk in terms of moving machinery and people; and based on that assessment an action plan needs to be in place to mitigate that risk,” Lourens says. “But there is still some uncertainty about exactly what mines must do, as the legislation has changed in the last decade from being very prescriptive to now being more reliant on the ‘reasonable man’ test. The law does not say exactly what activity must be carried out; rather, it says that the mine must mitigate the risk.”

He says there was also confusion on the issue of intervention. The Act deals with four industry categories: underground electric machines (where the law is clear that these must have an intervention system); underground diesel equipment (where only a warning system is required by law for now); surface diesel machines (which also legally require a warning system for now); and mining plant like refineries and smelters (where PDS requirements are not clearly defined).

“The revised MHSA allows for intervention systems on diesel machines underground and on surface, but is currently excluded from the promulgation so that’s where the confusion comes in,” Lourens says. “Underground electrical machines must have intervention systems while underground diesel machines don’t have to; it does appear that the requirement will be enforced, but not right now.”

Lourens says PDS technology is still being developed to fully cater for all the requirements of the revised law; hence the staged implementation of the various requirements. A global initiative by large mining companies – the Earth Moving Equipment Safety Round Table – was facilitating collaboration between stakeholders to help advance the technology.