Electrical Dangers in Underground Mines

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Electrical Dangers in Underground Mines

• Chris Faast

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Contents

• Introduction
• Power in the mining industry
• Dangers of electricity
• Causes of accidents
• Electrical safety tips
• Conclusion

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Introduction

• Adverse conditions encountered in underground
  mines are only made more dangerous with the
  addition of electricity
• Workers must be aware of the dangers that exist
• Training and safety advice should be given on a
  regular basis to protect all personnel

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Power in the mining industry

• Electricity used in thousands of applications
• Typical mine uses 35MW, in generators,
  transformers, switchgear and motors
• Voltage variation must be prevented
• Antamina mine, USA, uses 120MW powering around
  3000 AC motors

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Dangers of electricity

• Shock or electrocution
• 0.015 0.020 A, unable to let go of circuit
• 0.1 A causes death
• 240V may be just as lethal as 600V
• Possible to be shocked multiple times without
  effect. This is because the heart most vulnerable
  to shock inbetween heart beats.

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Dangers of electricity
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Dangers of electricity

• Switching components of an electrical system
  should be enclosed
• This prevents contact with metal particles that
  can cause injury, expelled under normal operation
• Short circuits may occur when working on
  equipment is due care not taken. Tools can make
  inadvertent contact.

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Causes of accidents

• Lack of training only allow qualified
  electricians to work on circuits
• Not turning power off planning is required to
  make set downtime for equipment to be worked on
• Rushing work time and care must be taken around
  electricity
• Misunderstanding electricity follow guidelines
• Energizing equipment qualified person must
  follow regulations when carrying out tests
• Not ensuring the circuit if OFF - circuit should
  be tested
• Leaving load on the circuit when restarting

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Electrical safety tips

• Treat electricity with respect and pay attention
  when working around it
• Report faulty equipment
• Wear appropriate personal protective equipment
• Carry out inspections of tools and power cords

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Electrical safety tips

• Ensure electrical equipment is grounded
• Do not knot cords, or allow vehicles to run over
  them
• Do not throw water on electrical fires
• Keep work area clean and free of rubbish allowing
  switches to be accessed quickly if necessary

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Conclusion

• Electrical accidents do happen
• Simple accidents can have devastating effects
• Employers must provide safety training and
  protect their workers through appropriate
  procedure