TECHNOLOGY
“ In terms of Section 21 of the Mine Health and Safety Act ( MHSA ), the equipment supplied by OEMs must be fit-for-purpose ,” he adds . “ If that equipment does not comply with the regulations , then the OEM can face both civil and criminal prosecution ; as the PDS supplier to the OEM , we would also bear responsibility .”
For this reason , it is demonstrably in the best interests of PDS suppliers to ensure that they offer the technology bestsuited to the application . After significant research and risk analysis to determine what the best fit-for-purpose technology for surface , Booyco decided to use GPS technology for vehicleto-vehicle detection , and very low frequency ( VLF ) technology for pedestrian detection . “ It delivers specific warning , controlled slowdown , or stopping zone alerts around a vehicle when detecting pedestrians or other vehicles ,” says Lourens .
However , the promulgation of the PDS legislation , and the looming implementation deadline of mid-2019 , has also resulted in an explosion in the number of PDS suppliers out there , including some fly-by-night operators that spring up just long enough to sell a few systems before disappearing , leaving the buyers without support or recourse , should anything go wrong .
“ Ten years ago , we were one of three PDS suppliers in South Africa ,” says Lourens . “ Today , there are over 40 operating in the market .”
And of these 40-plus PDS suppliers , only 28 are currently accredited , although this is a number that can change at any time . And while identifying and implementing the correct PDS technology for a particular operation is obviously the first – and most important – step . The fact that this technology will have a direct impact on site safety means that proper maintenance and support is just as important for the long term , which makes choosing a suitable supplier vitally important .
Risk assessment and implementation
Over the past year , the Mine Health and Safety Council ( MHSC ) has put together a committee that is driving PDS implementation , including risk assessment . The MHSC has also adopted the best practice guidelines laid out by EMESRT , which contain a variety of different scenarios for dealing with interactions between pedestrians , equipment and the environment ( see Figure 3 ). They have also put in place appropriate models based on these different scenarios that mines can follow to achieve a risk assessment that is acceptable to the DMR .
According to Lourens , the work that EMESRT has done on standardising the functional requirements of PDS technology has also done a lot to align the industry . “ Before the standard , any PDS supplier or OEM could supply a mine with the technology that they believed was best for the application , and there was no real alignment and no real practical way to measure function and performance . Now , companies need to supply technology that complies with these functional requirements if they want to be accredited PDS suppliers , and this is something that is measurable , and therefore enforceable .”
Once a mine has completed their base risk assessment and identified their significant risks , then PDS suppliers such as Booyco can assist the mines in determining how technology can be best used to mitigate the site ’ s specific risks . “ It ’ s an involved process , but given the significant capital costs of installing PDS technology , ensuring that you are only installing it where it is needed and will have the greatest effect can result in significant cost savings , versus placing it on all equipment , or on the wrong equipment and then needing to replace it ,” he says .
When it comes to the timeline for the three levels of control that specifically affect PDS technology , a lot is dependent on the level
EMESRT EMESRT
Figure 1 : EMESRT 9-step hierarchical type model based around design , operate and react .
Figure 2 : Unwanted event surface scenarios .
“ When it comes to the timeline for the three levels of control that specifically affect PDS technology , a lot is dependent on the level of complexity required for each one .”
of complexity required for each one . Level 7 is a basic warning , letting the operator know that there ' s a person , vehicle or piece of infrastructure within a specific distance of the vehicle . Level 8 is an advisory system that will suggest a course of action to the operator , such as to slow down or stop . And level 9 is an intervention , which will actually take control of the vehicle and cause it to slow down or stop .
While the basic warning level of technology is already operational – with varying degrees of success – Lourens says that the complexity of the algorithms required for the advisory and intervention levels of control will take significantly longer to finalise , although he is confident that this will be addressed in time for the deadline .
“ The problem is that the computational and processing power required for these control levels , as
18 _ QUARRY SA | JANUARY / FEBRUARY 2018