What kind of electrical hazards does a residual current device (RCD) protect against?

A residual current device (RCD) is specifically designed to protect against electric shock and fire hazards that can occur due to earth faults. It monitors the flow of electrical current in a circuit, detecting any imbalance between the live and neutral wires, which often indicates that current is leaking to earth. This leakage can happen if a person comes into contact with a live part or if there is faulty insulation.

When an imbalance is detected, the RCD quickly disconnects the circuit, significantly reducing the risk of serious electric shock to individuals and preventing potential electrical fires that could arise from such faults.

While electrical burns, overcurrent, overvoltage, and short circuits are all important considerations in electrical safety, they are not within the primary scope of protection provided by an RCD. RCDs are focused on detecting and interrupting earth fault currents, which makes option B the most accurate representation of the hazards addressed by these devices.