For structures exceeding 60 feet in height, what must be interconnected within the main roof level?

For structures exceeding 60 feet in height, it is essential that all grounded media be interconnected within the main roof level to ensure safety and effectiveness of the lightning protection system. This interconnection helps to provide a low-resistance path to ground for lightning currents, minimizing the potential for damage. Grounded media includes various components, such as down conductors, bonding conductors, and any equipment or structures that could become energized if struck by lightning. By ensuring that these elements are properly bonded and connected at the main roof level, the risk of hazardous electrical surges is greatly reduced.

This standard is based on the principles of lightning protection design, which focuses on providing a safe route for electrical discharge. Grounded media must work in harmony to prevent dangerous differences in potential that can arise if they are not properly connected. Ensuring that all grounded media are interconnected at that height is critical for the overall integrity of the lightning protection system and is in compliance with established safety standards and best practices.