An automatic combination of fire detection and suppression system can not only control a fire in an operation, but can also extinguish fires well before the fire department can arrive on scene. This could be achieved with less or none human intervention.
High quality automatic fire suppression solutions should be an integral part of fire detection and suppression solutions in line with Mining Regulations in all countries, in South Africa, the Mine Health and Safety Act cite fire as a principal hazard. Mine regulations stipulate that workers are not exposed to health and safety risks. Hence, the need for detecting and suppressing fire from the onset.
The primary approach fall sort
Potential sources of combustion in mines include gas (naturally occurring and introduced), diesel or petrol, engine coolant, lubricants, hydraulic fluid, sulphide dust, and other carboniferous material such as rubbish and waste. The primary approach undertaken to control and extinguish fire from such sources usually is water, foam, chemicals, rock dust or sand directly applied to contain or extinguish the fire. However, this method is only effective when extinguishing material is placed directly on the fire. In addition, the method is limited to only the very early stages of fire and places miners in close proximity with fire.
Why Automatic fire suppression essential
The time between the onset of fire and when it is detected and suppressed is critical since fires may intensify. Success of countering such risks with the primary approach would rely on the outcome of various factors.
To this end, adding automatic fire suppression systems and equipment in their operations mitigate potential fire risks from the onset of a fire, says Ronald S. Conti and colleagues (Linda L. Chasko, Charles P. Lazzara, Ph.D., and Gary Braselton), in their research project An Underground Coal Mine Fire Preparedness and Response Checklist: The Instrument. The authors point out that, in developing the control measures to manage the risks of fire or explosion, one of the key areas to be considered is the arrangement for the prevention of fires including early detection and suppression.
“An automatic combination of fire detection and suppression system can not only control a fire in an operation, but can also extinguish fires well before the fire department can arrive on scene. This could be achieved with less or none human intervention.”
This view is also emphasised by IEC 61508, an international standard consisting methods on how to apply, design, deploy and maintain automatic protection systems called safety-related systems. According to the standard, “not only must equipment operate correctly in response to its inputs, but it must be able to detect potentially dangerous conditions and activate corrective mechanisms to prevent fires, explosions or other hazardous events from arising.”
Moreover, the standards further indicate that, as far as reasonably practicable, fire suppression systems should be installed on all plant operating in underground mines. “Automatic fire suppression is especially important for unattended, automated or remote control equipment where personnel are not present to detect a fire, to activate a fire suppression system or to initiate fire-fighting operations.”
In mining operations, fires can result in serious injuries or death to workers, as well substantial damage to property and significant business disruption. Therefore, it is recommended that smoke and fire sensors be used, whenever possible as part of a mine atmospheric monitoring system, as they would give greater flexibility for setting alarm for fire detection at low smoke levels.