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Mine Rescue and Survival Interim Report (1969) / Chapter Skim
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Communications Subsystem
Pages 6-8

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From page 6...
... For the portable chamber, two types of bulkheads are being considered, rigid metal and inflatable. For metal bulkheads, trade-off studies are being conducted of aluminum versus steel, type of stiffening, weight versus size, weight versus pressure, and convex versus flat configuration.
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From page 7...
... Seismic Communications The requirements for a seismic system, as for an electromagnetic system, are that it be capable of rapid deployment, that it have sufficient sensitivity to detect the miner-generated signals at distances comparable to the dimensions of the area of possible entrapment, and that it be capable of locating the miners with sufficient accuracy that they can be reached by holes drilled from the surface or that fairly exact direction can be given to rescue teams. Although generally desirable, the ability to establish twoway communication between the miners and the surface is of secondary importance.
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From page 8...
... When ready to communicate, a series of hammer blows on the ground surface will tell the miners that they have been located and that they should stop sending their location signal and start sending the prearraged coded messages regarding their condition. With this system it would be possible to determine the number of miners trapped, their physical condition, the condition of the air in their vicinity, and perhaps an estimate of their survival time to provide the rescue team guidance on priorities with which they should explore various areas of the mine.
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Key Terms

  • refuge chamber
  • electromagnetic communications
  • coded messages
  • weight versus
  • voice transmission

  • trapped individuals
  • hammer blows
  • mine radio
  • keyed code
  • irregular topography

  • sufficient accuracy
  • surface searchers
  • rescue teams
  • seismic communications
  • ground surface

  • beacon underground
  • location accuracy
  • distances comparable
  • messages based
  • signal location

  • miner below
  • team guidance
  • audio oscillator
  • stop sending
  • rapid deployment

  • transmitting downward
  • below ground
  • sufficient sensitivity
  • convex versus
  • operational amplifier


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