Ermelo, 9 April 1987

At 18:30 on 9 April 1987, a methane gas explosion at the Tafelkop Shaft at Ermelo Mines, east of Johannesburg, claimed the lives of 34 mine workers and injured 17. One mineworker passed away a week later in hospital, bringing the total number of deceased to 35. The explosion occurred about 350m below the ground in the old section of the Gencor-owned mine, resulting in an inrush of carbon monoxide into the working places of the 9 West 1 South panel.

In days leading to the explosion, Ermelo had experienced severe thunderstorms and the mine’s management was concerned that this could trigger a methane gas explosion, as was the case at another nearby mine.

On the morning of 9 April, the mine’s management instructed its shift bosses to conduct safety inspections. At about 18:25, a shift boss noticed that an old mined out section had been sealed off with brattice in order to allow for ventilation into the new section. Puzzled by this, he moved away from the area to phone the surface, to alert his superiors. Five minutes later, a methane gas explosion ripped through the old section of the shaft, flinging the shift boss to the ground.

While the shaft was in complete darkness, he managed to find his way to the surface three-and-a half hours later, making use of four of the five long duration (60 minutes) self-rescue devices he had managed to grab from a cubicle in a through roadway. A total of 34 mineworkers who were in the direct line of the explosion succumbed to carbon monoxide poisoning. About 30 minutes after the explosion, surviving workers managed to walk out of the mine, using the self-rescuers.

The deceased were recovered by proto teams from Ermelo mines and neighbouring mines within 10 hours of the explosion. Some were found wearing the self-rescuers but the oxygen supply had not been opened. It is believed that the loss of life would have been worse, had it not been for the mine’s implementation of these self-contained self-rescuers that supply oxygen.

These self-rescuers were an innovation at that time with Ermelo Mines being the first to install them throughout its underground operations in 1986. The mine also provided training and staged mock evacuations.

Investigations by the mine, the government and research institutions into the explosion revealed that a build-up of methane in the 9 West 1 North panel could have been ignited by lightning as the explosion had occurred during a thunderstorm. Another theory was that the installation of the new brattice had been the reason for the methane build up and the subsequent explosion.

In order to prevent future methane gas explosions, fire patrol parties at the mine extended the monitoring of methane, carbon monoxide and carbon dioxide to off-shift periods. All worked out areas which were being ventilated from main intake airways were sealed off with explosion resistant seals.

Ermelo Mines subsequently introduced belt-worn self-rescuers to supplement the Ocenco self-rescuers. The mine’s management realised that, while the Ocenco self-rescuers had saved lives following the methane explosion, under stress, mineworkers might have forgotten the training they had received on how to activate these devices while accessing the cache might have been difficult.

From this incident it became a requirement that all coal mines in South Africa install self-contained self-rescuers and this concept spread worldwide. Ermelo Mines then installed an electronic gas monitoring system in September 1987, despite this not yet being a legal requirement.

The Leon Commission of Inquiry of 1993 led to the establishment of the Mine Health and Safety Council (MHSC). The MHSC highlighted methane gas explosions as a key area of concern in mine safety and health. The Mining Regulation Advisory Committee, under the auspices of the MHSC, appointed a tripartite task team to advise on measures to be taken in mitigating the risk of methane ignitions, although the focus of their study was on methane ignitions in coal mines where methane gas is more prevalent.

Recent innovations in dealing with methane gas include Anglo American Thermal launching a R9 million methane gas flaring project in 2010 at its New Denmark Colliery near Standerton. The project entailed using the flare to safely burn off methane.

The coal sector has made tremendous strides in terms of occupational safety and health.

The Minerals Council and its members are committed to ensuring that every mine worker returns from work unharmed every day. Through the lessons learnt from tragedies such as the one at the coal mine in Ermelo, the industry strives to avoid incidents of any kind, which result in a tragedy that affects many people.

Useful links