Taking Refuge

In September of 2012, wooden cable frames at a potash mine in Rocanville, Saskatchewan, caught fire, trapping 20 workers underground. From inside the mine, the workers were able to communicate with the outside world and stay safe, despite being trapped in smoky conditions for a day. No one was injured.

Six years earlier at a Mosaic Company potash mine in Esterhazy, Saskatchewan, 72 workers were trapped underground for 32 hours.ST Electronics' airpurifiertarget provides drivers with a realtime indication of available parking spaces. A fire had burnt the communication lines, so this time the workers could not be reached. We anticipated it would go bad, recalls Neil Crocker, Saskatchewans chief inspector of mines with the Ministry of Labour Relations and Workplace Safety in Saskatoon. Remarkably, after the fire was put out, the workers resurfaced safely without injury.

How did so many workers, trapped underground in such dangerous conditions,We are a special provider in best bulb,also a professional aluminumhoneycombpanels saler. manage to evacuate and stay safe? The answer lies in the sophisticated if not delicate system of mine rescue and mine emergency response.
Working in mines can be a dangerous business. Alex Gryska, manager of mine rescue at Workplace Safety North in Sudbury, Ontario, says underground mines can be particularly unforgiving. Each mine carries the potential for a myriad of hazards, such as rock bursts, ground collapses and asphyxiation.

In Canada, ground collapses may be the most dangerous of all. Youre working under rock, Crocker says. Its not a homogeneous, consistent medium like concrete. You cant predict rock all the time.

Providing access to clean air can also be a challenge, as underground air supplies can be easily contaminated. James Baumgartner, who works in mine safety with The Mosaic Company, says ensuring effective ventilation can be especially complicated in potash mines, which tend to be much bigger than other types. Youre in a really large confined space, he says, likening the area to a paper bag with two straws. Fresh air is circulated in one mine shaft, while exhaust comes out the other.

Underground mines also contain large, mobile equipment, some of which can pose electrical hazards. Last year, we had some equipment fires underground, Gryska recalls. The fires were caused by massive rubber tires or by diesel fuel, and could have threatened the safety of every worker, he says.

Coal mines in particular pose additional risks, since they feature what Crocker calls an explosive, burnable atmosphere. Michael Nelson, chair of the Department of Mining Engineering at the University of Utah in Salt Lake City, explains that if minerals are exposed to air, coal can release methane or hydrogen sulphide. This can be toxic to workers and even lead to explosions. At uranium mines, Nelson adds, miners can be exposed to radioactive particles in the air.

Despite all these risks, Nelson says mine safety is better managed compared to many other industries. The rate of serious injuries and fatalities in mining accidents has declined in many provinces. According to the Ontario Mining Association, the mining sector in the province has improved its lost-time injury rate by 91 per cent over the last 20 years.

Some of these risks have been mitigated by relatively new technologies that can help prevent disasters. Consider that carbon dioxide, carbon monoxide and nitrogen in the air quickly trigger alarms. Today, nearly all mines are equipped with sophisticated phone and radio systems to keep workers both inside and outside the mine in contact with one another.

Employees going into dangerous areas might also wear tracking devices, which can facilitate a quick rescue effort in the event of a rock fall. Other mines, including the Mosaic potash mine in Esterhazy, now include a card-tracking system which requires workers to swipe in every time they go underground, documenting their name on a computer for dispatchers off site.

In other cases, mining equipment has been automated or remote-controlled to reduce the number of workers entering perilous areas.

In some mines, a new device has been employed which can even determine whether or not an equipment operator is falling asleep by measuring their eye direction and blinking rates, reports Al Hoffman, chief inspector of mines for British Columbia. If an operator is deemed to be sufficiently tired, an alarm may sound to alert the worker and the pit control operator of his or her condition.

Despite these advancements, mining disasters can and do continue to happen across the country, and when they do, every site has a plan. Mine safety regulations vary slightly from province to province, but their procedures are fairly consistent.

When employees spot problems, they are instructed to first protect themselves. If the issue is minor, they might fix it themselves, whether that means putting out a small rag fire or turning off a vehicle with an electrical problem. But if the issue cannot be addressed or contained by workers in the immediate area, Crocker says their job is to retreat to a place of safety and start the emergency warning system.

To alert workers to emergencies, these systems take several forms, including flashing lights, phones, horns and sirens. Sometimes, workers are informed of emergencies by ethyl mercaptan injected into a mine, giving off a rotten egg smell. It is distinctive, you cant miss it, Crocker says with a laugh. The goal is to ensure that all workers, regardless of whether or not they are using loud equipment or working in low-light, get the message.

Once workers are alerted to an emergency be that a fire, ground collapse or a gas leak their responses will vary depending on the type of emergency and the type of mine. In coal mines, Crocker says workers are evacuated immediately since there is a risk of explosion. If they must stay in a safe area within the mine, it must be one without electricity.

In most other underground mines, employees are typically directed to their nearest refuge stations self-contained units where they can go to stay safe until they can be retrieved by a mine rescue team. These units usually contain air masks, breathable air, first aid equipment, potable water and any other equipment workers may need to survive for days. Some even contain toilets, food and entertainment, such as playing cards or board games.