Mine Emergency Preparedness Training

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Mine Emergency Preparedness Training
Mine Recovery
2
Introduction
The main objective of recovery work is to put
the mine or affected area of the mine back in
operation as soon as conditions permit after a
mine disaster.
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Assessing Conditions

• Initial assessment of underground conditions.
• How much rehabilitation work is needed to recover
  the affected area.
• The extent of damage to the ventilation system.
• Checking gas conditions and roof and rib
  conditions.
• Checking the condition of track, waterlines,
  power lines, and phone lines.

4
Re-establishing ventilation after a fire or
explosion

• Reestablishing ventilation and bring fresh air to
  an area damaged by fire or explosion.
• Note no ventilation changes should be made
  without the consent of the Command Center.

5
Unsealing a fire area

• Planning
• Step-by-step plan.
• Communications
• Records

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When to unseal

• The extent and intensity of the fire at the time
  of sealing
• The characteristics of the burning material and
  the surrounding strata
• The tightness of the seals
• The effect of barometric pressure on the enclosed
  area
• The effect of temperature on the enclosed area
• The location of the fire area with respect to
  ventilation
• The gas conditions as indicated by analysis of
  air samples taken behind the seals. Usually the
  gases analyzed oxygen, carbon dioxide, carbon
  monoxide, methane, hydrogen, and nitrogen.

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Preconditions for opening a sealed fire area

• Oxygen content behind seal low enough to make an
  explosion impossible
• Carbon monoxide not present behind seal.
• Area behind seal has had sufficient cooling time.

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Preparations for opening a sealed fire area

• Adjust ventilation so toxic/explosive gases
  released from the sealed area are directed into
  main returns.
• An observer should be stationed at the main
  fan(s) to warn the rescue team of any fan
  malfunctions.
• An observer should be stationed in the main
  returns to monitor gas levels.
• Cut off all electrical power.
• Rock dust all entries and crosscuts leading to
  and from the sealed area.
• Withdraw all unnecessary people from the mine.

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Methods of Unsealing Fire Areas

• There two basic methods that can we used for
  unsealing a fire area progressive ventilation
  and direct ventilation.
• Progressive ventilation is the reventilation of a
  sealed area in successive blocks by means of air
  locks.
• Direct ventilation is the reventilation of the
  entire sealed area at once.

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Recovery by By Progressive Ventilation

• Air locking operations should never be undertaken
  until the oxygen content of the air behind the
  seals has been reduced to at least two Percent.
• The first step in progressive ventilation is to
  build a stopping at one of the seals on the
  intake side of the fire area to create an air
  lock.
• The distance between air locks is usually between
  200 and 500 feet. It depends on the conditions
  encountered and the amount of construction work
  that is needed to prepare an area for
  re-ventilation

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Air Lock

• An air lock is made by building two stoppings 10
  to 15 feet apart.
• Each stopping should have a door or flap in it so
  that teams can enter and exit the sealed area.
• One opening in an air lock must be closed while
  the other is open to prevent mixing of the two
  atmospheres.

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Entering Sealed Area
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Fire
Air Flow Stopping opened for return air
SEALED
AIR LOCK
Sealed Area and First Air Lock
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Reventilation
Fire
Air Flow Stopping opened Reventilation of
area Remainder of Stoppings Opened
SEALED
AIR LOCK
AIR LOCK
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Recovery by Direct Ventilation

• The affected area is recovered and re-ventilated
  as a whole rather than by successive blocks.
• As a result, recovery is accomplished more
  quickly than with progressive ventilation, but
  gas conditions are less controlled.
• Before using direct ventilation, there should be
  conclusive evidence that the fire has been
  extinguished.

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Preventing a Buildup of Gases and Smoke in the
Fan House
Exhausting fans should be made to prevent the
buildup of explosive gases and smoke in the fan
house.
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Reventilation After an Explosion

• Areas of Concern
• The concentrations of explosive gases. Are they
  below, within, or above the explosive ranges.
• The percent of oxygen present. Will it support
  life? Is it low enough to prevent another
  explosion?
• Are possible sources of ignition being
  considered and eliminated-electrical power,
  battery-powered equipment, possible fires and hot
  spots, sparks from tools and team equipment.
• While exploring and preparing an area for
  re-ventilation, teams should be on the alert for
  and eliminate any possible sources of ignition.

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Monitoring

• During reventilation work, an observer should be
  stationed at the main fan to ensure it is
  operating correctly and to warn the team in case
  of any malfunction.
• Also, someone should be monitoring gas levels at
  the main returns.
• Changing roof conditions shall be monitored
  continuously.

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Clearing and Rehabilitating the Affected Area

• Roof and rib control.

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Pumping Water

• There are two ways of accomplishing this
• Advance fresh air to the area and then pump.
• If the area needs cleared before they advance
  fresh air, if gas conditions permit, they can use
  non-conducting suction lines with a pump set up
  in fresh air to pump water.
• Careful analysis should be made of the gas
  conditions in the area being pumped.
• Water soluble gases will be pumped out along with
  the water.
• When advancing into an area that has been
  inundated with water, pay attention to roof and
  rib conditions.

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Loading Out Falls and Hot Debris

• Many times the most practical means of dealing
  with debris found during recovery operations is
  to load it onto shuttle cars and/or mine cars and
  haul it from the mine.
• The material should be wet down before and during
  loading operations.
• In situations in which large areas of heated roof
  rock have fallen, water lances can be driven into
  the debris to aid in cooling.

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Water lance
Water Hose
10 foot length of pipe welded closed at the ends.
With holes cut along its length