What minimum clearance is required in front of a switchboard installed in one line?

The minimum clearance required in front of a switchboard is specified to ensure safety and accessibility for maintenance, operation, and emergency response. A clearance of at least 5 feet is mandated in front of electrical equipment, including switchboards, to allow for adequate space for personnel to work safely and to prevent any potential hazards. This distance helps to safeguard against electrical shock and provides room for equipment, such as ladders or tools, that may be necessary during maintenance activities.

The 5-foot requirement is in accordance with safety standards and building codes, which strive to ensure that the work environment remains secure for workers. By maintaining this clearance, technicians and electricians can perform their tasks without the risk of coming too close to live components or equipment. Furthermore, it aligns with industry best practices that prioritize worker safety in electrical installations and maintenance.

The other options for minimum clearances are either above or below this standard, which could lead to a higher risk of accidents or difficulties in accessing the switchboard during necessary inspections or repairs. Thus, the choice of 5 feet is not just a regulatory requirement but also reflects an understanding of practical safety needs in electrical work environments.