The NESC covers utility generation, transmission, and distribution systems up to the service point, which is often a watthour meter. The National Electrical Code then covers premises wiring beyond the service point, within buildings and similar structures.
The NESC is used throughout the U.S. and in over 100 countries. It is updated every five years to reflect changes in the electrical and communications industries. The new 2007 edition has been updated in many ways, including:
• Grounding of metal poles and structures
• Clearances between electric transmission lines
• Multiplex cable attachment to neutral brackets
• Loading due to extreme wind and freezing rain
• Equipment bonding
• Electric-arc exposure analysis
• Antenna radiation exposure limits
