Which class of materials is used for lightning protection of buildings not exceeding 75 feet?

The use of Class I materials for lightning protection of buildings not exceeding 75 feet is based on the standards set by the Lightning Protection Institute and industry practices. Class I materials are designed specifically to handle the high-energy events associated with lightning strikes. They provide optimal conductivity and durability, ensuring that any lightning energy is effectively intercepted and safely transmitted to the ground without causing damage to the structure or creating hazards.

Class I materials are typically composed of high-quality metals such as copper or aluminum, which are favored for their excellent electrical conductivity and resistance to corrosion. This is crucial in maintaining the longevity and efficacy of the lightning protection system, as these materials must withstand not only the direct impact of lightning but also environmental factors over time.

In contrast, the other classes of materials, while possibly having their own applications, do not meet the rigorous standards required for effective lightning protection at this building height. For instance, Class II materials may be suitable for different circumstances or applications, but they typically lack the precise specifications needed for higher protection standards associated with Class I. Hence, for structures under 75 feet, the reliance on Class I materials ensures both compliance with safety standards and effective lightning protection.