New York State Master Electrician Practice Exam

When must exposed live parts of electrical equipment be guarded against contact?

1. When operating at 25 Volts or more

2. When operating at 35 Volts or more

3. When operating at 50 Volts or more

4. When operating at 75 Volts or more

The correct answer is: When operating at 50 Volts or more

Exposed live parts of electrical equipment must be guarded against contact when operating at 50 Volts or more due to safety standards and regulations intended to protect individuals from electric shock. The reasoning behind this threshold is that at or above 50 Volts, the potential for causing bodily harm increases significantly, and protective measures become necessary to ensure safety in environments where untrained personnel may be present or where contact may occur accidentally. Guarding exposed live parts can include enclosures, barriers, or insulation, which provide a physical separation between individuals and the electrically energized components. Regulations, such as those outlined by the National Electrical Code (NEC), underscore this requirement to minimize the risk of electrical accidents, emphasizing the importance of adhering to industry standards for safety practices in electrical installations.