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    1. Identify electrical hazards, including:
      • damaged insulation
      • overheating of cables
      • damp conditions.

Damaged Insulation:
In a circuit, insulation is the plastic sheath that covers wires. If you have damaged insulation, it means that metal wires inside the cable are exposed.
If a person touches the exposed wires, they could be electrically shocked, which may lead to death.

Overheating of cables:
When a very high current is run through a cable, there is a  risk of overheating the wire due to too much energy. This overheating could lead to electrical fires.

Damp conditions:
Since water is a conductor, during damp situations such as inside a bathroom, electricity from the electrical appliance may electrocute nearby people through the conductive water. Even skin, if wet, will electrocute the person if they touch a socket.

  1. Demonstrate understanding of the use of circuit-breakers.

A circuit breaker is a safety device that forces a circuit to open (switch off) when an extremely high level of current flows through the circuit.

  • Electricity flows in the circuit breaker through the metal contacts.
  • If an extremely high current flows through the circuit breaker, the electromagnet gets stronger and pulls the iron catch towards it.
  • This causes spring to pull the metal contacts apart, causing the circuit to open/break.


  1. Demonstrate understanding of the use of fuses.

Fuses protect components in a circuit from overheating by breaking circuit. A high level of current flowing through the circuit causes the wires inside the circuit to heat up. The fuse, a metal wire with a low melting point, will melt and cause the circuit to break. fuse



Notes submitted by Lintha

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One thought on “P12.6 – Dangers of Electricity

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