At approximately 6:15 a.m., December 7, 1992, an explosion occurred on the 1 Left section of Southmountain Coal Co.  Inc.'s No. 3 Mine at Norton, Virginia.  Eight miners were killed, and another miner working in an outby area was injured.

MSHA investigators concluded that an open flame from a cigarette lighter found on the mine floor was the ignition source.  Persons were smoking in the mine, and the operator's smoking search program was not effective.  One cigarette pack containing nine unsmoked cigarettes was found on a victim located at the point of origin, and ten smoked cigarettes were found in his pockets.

The bleeder system of the pillared 1 Right off 1 Left, 2 Right off 1 Left, and 1 Left section was not examined or maintained to continuously move methane-air mixtures away from the active faces.  The condition of the mine roof in the bleeder entry had deteriorated to the point that the bleeder entry had not been examined for several weeks.  Methane, liberated mostly from the closely overlying Kelly Rider seam, accumulated in the pillared areas of the bleeder entry.

Ventilation controls, both permanent and temporary, on the active working section had been removed, or had not been maintained.  This action allowed the methane to migrate from the pillared area and bleeder entry to the No. 1 entry and in the No. 2 crosscut between No. 1 and No. 2 entries.  Other factors included the dip of the coalbed, the drop of the barometric pressure before the explosion, the possibility of water accumulations, and roof falls occurring within the pillared areas and bleeder entry.

The methane was ignited on the 1 Left section in the No. 2 crosscut between the No. 1 and No. 2 entries by an open flame from a butane cigarette lighter.

The methane explosion resulted in sufficient forces and flames to suspend and ignite coal dust in 1 Left.  The coal dust explosion continued to propagate the entire distance of the No. 1 West Main entries to the surface area of the mine.

Conditions and practices that contributed to the explosion include:

• Improperly conducted weekly examinations for the No. 3 Mine and the 001 section on November 21-30, 1992.  The certified examiner failed to examine the bleeder system in its entirety due to adverse roof conditions.
  
  
• An inadequately conducted smoking search program.  Smoking material was found with three of the victims, and a lunch container was found to contain two full packs of cigarettes and two cigarette lighters.
  
  
• Failure to conduct a thorough preshift examination on the 001 section between 9:30 p.m. and 10:30 p.m.  on December 6, 1992, for the oncoming midnight shift on the 1 Left 001 section.
  
  
• Improperly placed and maintained ventilation control devices.
  
  
• Failure to maintain the required incombustible content of the mine dust.
  
  
• Failure to follow the approved ventilation plan in the bleeder system inby No. 1 Left 001 section.
  
  
• Failure to provide the necessary volume and velocity of air in the 1 Left 001 section.
  
  
• Failure to conduct weekly examinations of the ventilation system at least every seven days.

Source:
	Historical Summary of Mine Disasters in the United States - Volume II