Modern Mining October 2020

the urgent need for best practice

with a view to install additional units for the rest of the operation next year.” Refuge chamber monitoring MineARC’s latest refuge chamber advancement is its GuardIAN Refuge Chamber Monitoring System, which provides information on variables such as the control system, gas readings and the sealing capac- ity of the chamber to a central location. The control room either views this information on a dashboard or the system can be configured to send alerts to the relevant departments. The GuardIAN system has now expanded to include site-wide environmental monitoring, person- nel tracking and navigational smart lighting. “Many sites are adopting this system as they are following the smart mining route,” says Van Niekerk. He refers to Mopani’s underground SOB/ Synchlonorium mine as one of the first sites globally to implement the technology. Since then, MineARC has installed GuardIAN at over 10 other sites across Africa, including in Zimbabwe and Ghana. 

locally and equips them to its own minimum stan- dards, although some components, such as the air scrubbing systems, are manufactured at its head- quarters in Australia. “Some clients have custom requirements, add-ons which don’t necessarily form part of the best-practice standard,” says Van Niekerk. “These include sites with no compressed-air lines. In such cases, we use positive pressure maintenance sys- tems to artificially create the positive pressure environment which would normally have been pro- vided by compressed-air.” A modular approach for SA Van Niekerk recalls that refuge chamber sales were initially met with “pushback” in South Africa as local mining operations are mostly shaft mines, posing the practical problem of transporting the units down the shafts as they are often too large to fit the mine cages. “The solution lay in modular construction: the refuge chambers are divided into sections small enough for the cage, and then moved into place and assembled underground. We have supplied three-piece units in South Africa and, in Ghana, we installed a refuge chamber in seven modular units due to an especially small cage.” He says MineARC’s mobile refuge chambers typically accommodate from four to 30 people while the largest installed permanent chamber on record caters for 600 persons. In Zimbabwe, the company even installed a unit in three sections at a mine with a working height of only 1,6 m. “We accommodated this low working height by manufacturing the chamber to a height of 1,575 m. The client is currently conducting studies on this unit

Key Takeaways  While legislation in South Africa requires emergency refuge chambers at underground mines, the safety guidelines are vague  The rest of Africa has a better understanding and acceptance of best prac- tice standards than South Africa  MineARC has assisted some African countries with the Western Australian, Turkish and US guidelines on emergency safe refuge systems  Local mining operations are mostly shaft mines, posing the practical prob- lem of transporting the units down the shafts  The refuge chambers are divided into sections small enough for the cage, and then moved into place and assembled underground

October 2020  MODERN MINING  27