What are the minimum requirements for a Class I copper main lightning conductor?

For a Class I copper main lightning conductor, the minimum requirements include a specific gauge of copper that ensures adequate conductivity and structural integrity during a lightning event. The correct choice states that the conductor must be 17 AWG, weigh 187 pounds per 1,000 feet, and provide a cross-sectional area of 57,400 circular mils.

The combination of these specifications is critical for the effectiveness of the lightning protection system. The gauge of 17 AWG dictates the conductor's ability to carry the lightning current without overheating or failing. The specified weight and circular mils provide verification that the conductor is capable of handling the potential energy from a lightning strike, ensuring that it can properly dissipate the energy away from the protected structure.

This choice correctly encompasses all essential dimensions and weight, emphasized in lightning protection standards, which prioritize both conductivity and durability. Therefore, the requirements outlined in this choice align with industry standards, making it the best option for ensuring optimal lightning protection.