P12.6 – Dangers of Electricity

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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.

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.

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