Monongah mining disaster
Date: December 6, 1907
Location: Monongah, West Virginia, U.S.
Coordinates: 39°27'37"N 80°12'49"W
Cause: Coal mine disaster
Casualties: 362 killed
The
Monongah mining disaster was a coal mine explosion on December 6, 1907, at Fairmont Coal Company's Nos. 6 and 8 mines in Monongah, West Virginia, which killed 362 miners. It has been described as "the worst mining disaster in American history" and was one of the contributing events that led to the creation of the United States Bureau of Mines.
The disaster

Rescuers going into the mouth of the No. 6 mine, newspaper photo.
On Friday, December 6, 1907, there were officially 420 men in the two mines, although the actual number was much higher as officially registered workers often took their children and other relatives into the mine to help. At 10:28 AM, an explosion occurred in one section of the mine, followed by a larger explosion in another area, instantly killing most of those inside. The blast caused considerable damage to both the mine and the surface. The ventilation systems, necessary to keep fresh air supplied to the mine, were destroyed, along with many railcars and other equipment. The entrance and ventilation fan of No. 8 mine were destroyed, "but did little damage to No. 6 slope."
Inside the mine the timbers supporting the roof were blown down, which caused further problems as the roof collapsed. An official cause of the explosion was not determined, but investigators and representatives from both the Fairmont Coal Company and the Federal Geological Survey put forth theories that an electrical spark or one of the miners' open flame lamps ignited coal dust or methane gas.
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