At Murray & Roberts Cementation, safety enjoys the top slot in the list of priorities. “As part of our concerted safety drive, we have now established the use of collision warning systems as a pre-requisite for all new operations,” Neil Lane, engineering services executive, says. “No project will be permitted to start without such a system in place.”
The solution selected is the Booyco Electronics Collision Warning System. This is a first for Murray & Roberts Cementation, reflecting the proactive stance the company has adopted towards safety issues, and it represents a significant investment in the interests of safety.
“Visibility underground always presents challenges,” Lane explains. “Both the machines themselves as well as the nature of the underground layout restrict visibility for machine operators and pedestrians. Collisions between vehicles as well as with pedestrians are a constant risk, so we looked for a solution to provide complete two-way communication between vehicles and pedestrians as well as from vehicle to vehicle. The answer was Booyco’s CWS 800 Plus which offers this vehicle-to-vehicle collision detection capability in addition to the traditional pedestrian alert.”
The CWS 800 Plus allows both detection of people in close proximity to vehicles and longer range vehicle-to-vehicle detection. Previously, two separate technology systems were required: close proximity, low frequency technology to detect people close to vehicles and a separate and alternate system for vehicle-to-vehicle detection. This technological configuration resulted in greater cost to the customer.
“The combination is a first in South Africa,” Lane continues. “The technology now incorporates both UHF RFID (Ultra High Frequency Radio Frequency Identification) and VLF (Very Low Frequency) capabilities. “VLF is the only reliable technology for collision warning underground, providing through-rock penetration so that pedestrians are alerted to oncoming vehicles even around rock walls and corners.”
Every pedestrian is fitted with a VLF tag which is tested before the miner goes underground. “His ID number is recorded, so at all times, there is an accurate determination of who is underground,” he says.
“An added advantage of the CWS 800 Plus is that its parameters can be adjusted from one to 12 metres for pedestrians using VLF and up to 50 metres for vehicle-to-vehicle alerts using UHF. A flashing light and buzzer warn the pedestrian of oncoming vehicles whereas a visible and audible alarm in the vehicle cab caution the operator to stop immediately.”
Lane explains that Murray & Roberts Cementation has established a five metre perimeter for its CWS units since the trackless machines used are slow moving with short stopping distances. “This provides 10 metres between vehicles which is an accepted industry standard,” he adds.
Other functionalities include remote activation of ventilation doors by vehicles which adds further to safety benefits. In addition to the inherent advantages of VLF technology, the system incorporates very intelligent IP to ensure that the UHF is reliable and accurate. A further advantage is that the system is not adversely affected by surrounding equipment or the presence of ore bodies.
“The system, which is simple to implement, is being rolled out in a phased approach to our contracts,” Lane says. “We have already installed units at Wessels Mine and Lonmin’s Pandora Mine and will shortly install units at Kroondal Shaft Banbanani, Anglo Coal Goedehoop and BHP’s Khutala. Extensive training is provided to all miners as well.
“I have little doubt that this collision warning system will eventually become a prerequisite in any mining operation.”
