The automation of the "making safe" process in South African hard-rock underground mine

Abstract

In South African hard-rock mines, best practice dictates that the hanging-walls be inspected after blasting. This process is known as ‘making safe’ and although intended to save lives, it is laborious and subjective. Pressure is placed on the barrer (inspector) to conduct the test quickly and efficiently as daily operations can only continue after the area has been declared safe. The process involves the barrer tapping the potentially loose rock mass with a sounding bar, listening to and assessing the generated acoustics, and deciding whether it is intact or loose. For a loose rock mass, the barrer would either bar it down or support it. For the purposes of this report, only the ‘making safe’ process is considered. It is highly dangerous and limits the critical decision making to the experienced barrer. Fatality rates due to falls of ground (FOG) can be reduced by implementing a simple tool that will give consistent results in the ‘making safe’ exercise.