On-line version ISSN 2411-9717
J. S. Afr. Inst. Min. Metall. vol.110 n.1 Johannesburg Jan. 2010
New technology for real-time in-stope safety management
D. Vogt; A. V-Z. Brink; P.C. Schutte
CSIR Centre for Mining Innovation
South African underground hard rock mines are typically managed using measurements made daily, weekly or even monthly of key parameters such as face advance, readiness to blast, blast success, temperature or dust levels. Safety and health can be greatly improved if a real-time measurement system can inform decision making.
To enable this vision of widespread sensing, communication and decision support, CSIR has developed an open standard architecture for communication of sensor data, and a reference implementation using that standard. The standard is called AziSA, which means 'to inform' in isiZulu. AziSA provides an architecture that allows for connection of any type of sensor and that is particularly suited to wireless sensing.
On the safety side, the CSIR is developing a suite of sensors specifically around the risk of rockfalls. Sensors such as an electronic replacement for the barring tool, or a thermal sensor that can detect loose rock, can already be used to identify potential hazards in the hangingwall. When these sensors are combined with location and time information in a single database, it becomes possible to build maps of risk and to extrapolate risk into unmined areas. It is also easy to confirm that routine safety procedures like barring are actually taking place.
In the future, it is proposed that entry inspections will be made using remote techniques that will not place an individual miner at risk. While miners will still be required to bar or place support, they will do so with a clear idea of which portions of the hangingwall are safe, and which present risk.
On the health side, if a network such as AziSA is deployed in the stope, it becomes much easier to monitor the condition of individual miners. The work strain experienced by miners can be monitored through heart-rate sensors, and their core body temperature can be monitored using various novel techniques discussed in the paper. Additional sensors can be added to quantify worker exposure to hazards such as noise or dust.
Individual sensors allow for people who are at an unacceptably high risk of developing heat disorders to be treated timeously, and they also allow for team management based on objective measures. Over a longer period, position sensing and environment monitors, or personal dosimetry, provide a powerful management tool to prevent workers from being overexposed to hazards, and to confirm that management instructions are being followed.
Cost-effective sensing in the stope is a major challenge, but one that can be overcome through technology like that used in AziSA. Sensing provides opportunities both to make immediate interventions when workers are exposed to unacceptable risk, and to manage the long-term exposure of workers to hazard.
“Full text available only in PDF format”
1. Ackoff, R.L. From Data to Wisdom, Journal of Applied Systems Analysis, vol. 16, 1989. pp. 3-9. [ Links ]
3. Blackburn, M.R., Everett, H.R., and Laird, R.T. After Action Report to the Joint Program Office: Center for the Robotic Assisted Search and Rescue (CRASAR) Related Efforts at the World Trade Center, Technical document 3141, Space and Naval Warfare Systems Center, San Diego. 2002. [ Links ]
4. Brink, A.v.Z., Roberts, M.K.C., and Spottiswoode, S.M. Further assessment of seismic hazard/risk in the Bushveld Complex platinum mines and the implication for regional and local support design, SIMRAC Report GAP 821, Department of Mineral and Energy Affairs, South Africa. 2002. [ Links ]
5. Brink, V.-Z. and Roberts, M. K. C. Early Warning and/or Continuous Risk Assessment of Rockfalls in Deep South African Mines, 4th International Seminar on Deep and High Stress Mining, Perth, Australia, 7-9 November 2007. [ Links ]
6. Ferreira, G. An implementation of ultrasonic time-of-flight based localization, 2nd International Conference on Wireless Communication in Underground and Confined Areas, Val-d'Or, Quebec, 25-27 August, 2008. [ Links ]
9. Kinney, P. ZigBee Technology: Wireless Control that Simply Works, IEEE Communications Design Conference, Oct 2003. [ Links ]
10. Moran, D.S., Shitzer, A., and Pandolf, K.B. A physiological strain index to evaluate heat stress. American Journal of Physiology, vol. 275, R129-R134. [ Links ]
11. Oldroyd, D.C. A feasibility study of thermal imaging equipment to identify potential rockfalls, SIM 040202, Department of Mineral and Energy Affairs, South Africa, 2006. [ Links ]
12. Schutte, P.C. and Franz, R.M. The influence of heat stress on human performance and cognitive ability. DEEPMiNE Research Report No. 20000231. May 2000. [ Links ]
13. Stewart, R., Donovan, S.J., Haarhoff, J., and Vogt, D. AziSA: an architecture for underground measurement and control networks, 2nd International Conference on Wireless Communication in Underground and Confined Areas, Val-d'Or, Quebec, 25-27 August, 2008. [ Links ]
14. Stopforth, R., Holtzhausen, S., Bright, G., Tlale, N.S., and Kumile, C.M. Robots for Search and Rescue Purposes in Urban and Underwater Environments-a survey and comparison, 15th International Conference on Mechatronics and Machine Vision in Practice, 2-4 December 2008, Auckland, New Zealand, 2008. pp. 476-480. [ Links ]
15. Strydom, N.B. The need for acclimatizing labourers for underground work. Journal of the Mine Ventilation Society of South Africa, vol. 19, 1966. pp. 124-126. [ Links ]
16. Vogt, D., Brink, A.V-Z., Stewart, R., Donovan, S., Haarhoff, J., and Ferreira, G. AziSA: improving mining decisions with real time data. Third International Platinum Conference 'Platinum in Transformation', The Southern African Institute of Mining and Metallurgy, 2008. [ Links ]