What is the minimum depth of working space required in front of an electrical panel operating at 120 volts?

The minimum depth of working space required in front of an electrical panel operating at 120 volts is established to ensure safety and accessibility for maintenance and operation. A depth of 3 feet—commonly used in the National Electrical Code (NEC) guidelines—provides enough room for an electrician to work safely without interference from other objects or the surrounding environment. This space allows for adequate maneuverability, essential tools access, and emergency measures, such as quickly shutting off power if necessary.

Maintaining a sufficient working space not only promotes safety but also ensures compliance with regulatory standards that aim to prevent accidents and injuries in electrical installations. The other depth options do not conform to the standard requirements established for typical residential and commercial setups involving 120-volt systems, which is why they do not meet the criteria for minimum working space in this context.