What is the first action a technician should take to prevent electrical hazards while servicing a PC?

Disconnecting the power before servicing a PC is crucial for preventing electrical hazards. When a technician begins to work on a computer, the first priority should always be ensuring that the device is completely powered off and disconnected from any electrical source. By doing so, the technician eliminates the risk of electrical shock and the potential for damaging the computer's components due to accidental short circuits.

While the other safety measures, such as wearing an ESD strap, using insulated tools, and placing components on an ESD mat, are important for protecting against electrostatic discharge and other potential hazards, they do not address the immediate risk of electrical shock from power flowing through the system. Ensuring that the device is powered off is the foundational step that enables the technician to safely implement those other safety practices. Without this initial step, all other precautions may still leave the technician vulnerable to serious injury.