For a typical residential panel operating at 120/240 volts, the required depth of the clear space is 36 inches, measured outward from the face of the enclosure. This 3-foot depth is the minimum horizontal distance necessary for a person to stand and work safely. Electrical clearances are the minimum separation distances the National Electrical Code (NEC) requires between wiring, panels, overhead conductors. NEC Article 314 establishes requirements for the installation and use of electrical boxes, conduit bodies, fittings, and handhole enclosures. The rules are all about safety, and there are basically two ideas. Working space: The front clearance, side clearance, and height clearance requirements for electrical equipment that provide a safe area for maintenance, inspections, and other work.
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