Depth: 3 feet minimum from the panel face to any wall or obstruction. Width: If the panel is 24 inches wide, the space must be at least 54 inches wide (24″ + 30″). In a control room with a switchgear assembly: A minimum clearance of 3 feet in front. This guide breaks down the real relay room design standards used across utilities and industrial facilities, including the IEC and IEEE frameworks engineers rely on, common compliance pitfalls, and the differences between substation and industrial protection rooms. Key Insight: Relay room standards. Here are some key NEC – 2023 codes and requirements related to electrical panels: The working space depth for panelboards up to 600V are mentioned in NEC 110. Clearance: Electrical panels must be installed in a readily accessible area with a minimum clearance of 30 inches (762 mm) wide. Working space is not required in back of assemblies such as dead-front switchboards or motor control centers where there are no renewable or adjustable parts such as fuses or switches on the back and where all connections are accessible from locations other than the back.
[PDF Version]