Journeyman Electrician Practice Exam

What must electrical equipment be marked to indicate when likely to require servicing while energized?

1. Electrical load capacity

2. Potential arc flash hazards

3. Service disconnecting means

4. Voltage ratings

The correct answer is: Potential arc flash hazards

Electrical equipment must be clearly marked to indicate potential arc flash hazards when there's a likelihood of requiring servicing while energized. This marking is crucial because it warns individuals working near or on the equipment about the risk of arc flash events, which can occur due to the presence of electrical energy. Arc flash incidents can lead to severe injuries or fatalities, so proper labeling is essential for safety. Understanding the potential for an arc flash helps electricians and maintenance personnel take necessary precautions, like using appropriate personal protective equipment (PPE) and employing safe work practices when working on energized equipment. While the other aspects like electrical load capacity, service disconnecting means, and voltage ratings are important for overall system safety and functionality, they do not specifically highlight the risks associated with working on energized equipment as effectively as arc flash hazard warnings do. Hence, the focus on marking potential arc flash hazards reflects best practices in maintaining electrical safety standards.