We care and we remember

Ermelo, 9 April 1987

At 18:30 on 9 April 1987, a methane gas explosion at the Tafelkop Shaft at Ermelo mine, east of Johannesburg, claimed the lives of 35 mine workers and injured 17 as a result of carbon monoxide poisoning. The explosion occurred about 350m below surface in the old section of the Gencor-owned coal mine, resulting in an inrush of carbon monoxide to the working places of the 9 West 1 South panel.

In the days leading up to the explosion, Ermelo had experienced severe thunderstorms and the mine’s management was concerned that this could trigger a methane gas explosion, which had already occurred at a neighbouring mine.

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

With the shaft 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 hour-long self-rescue devices. Half an hour after the explosion, surviving workers managed to walk out of the mine using self-rescuers.

The bodies of those who died were recovered by proto teams from Ermelo mine and other neighbouring mines. Some were found wearing their self-rescuers, however 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 prior implementation of these self-contained self-rescuers that supply oxygen.

These self-rescuers were an innovation at the time, with Ermelo mine 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 revealed that a build-up of methane in the 9 West 1 North panel, possibly due to the installation of the brattice, could have been ignited by lightning as the explosion had occurred during a thunderstorm.

Ermelo mine subsequently introduced belt-worn self-rescuers to supplement the self-rescuers available. The mine’s management realised that, while the first self-rescuers had saved lives following the methane explosion, under duress, mineworkers might have forgotten the training they had received on how to access and activate them.

After this tragedy, it became a requirement that all coal mines in South Africa have self-contained self-rescuers available and this concept spread worldwide. Ermelo mine also installed an electronic gas monitoring system in September 1987, although this was not yet a legal requirement.

The Leon Commission of Inquiry into Safety and Health in the Mining Industry 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 task team to advise on measures to be taken to mitigate the risk of methane ignitions, although the focus of its study was on methane ignitions in coal mines where methane gas is more prevalent.

The study, released in 1994, described a new method – the building of stone dust barriers – to limit coal dust and methane explosions in coal mines. Today, the South African coal mining industry has systems based on improved technologies to test and modify active suppression methods. Better detection technology and communications channels have improved mines’ capacity to manage the methane threat.

There has been innovation in managing and reducing the amount of methane gas in mines across South Africa using gas drainage systems and pathways. An important study revealing their effectiveness was done at Beatrix Gold Mine in 2011, where 55% of the total volume of methane gas from the general body of the air in the mine was released safely into the atmosphere, markedly reducing the risk of methane-related incidents.

The Minerals Council South Africa and its members are committed to ensuring that every mine worker returns home from work unharmed every day. Sharing experiences and lessons learned assists the industry in meeting this commitment now and into the future.