Which of the following material forms may be used for air terminals?

Air terminals, commonly referred to as lightning rods, can be constructed from a variety of materials including copper, aluminum, and zinc. Each of these materials has properties that make them suitable for use in lightning protection systems.

Copper is well-known for its high electrical conductivity and resistance to corrosion, making it a reliable choice for air terminals. Aluminum, while slightly less conductive than copper, is lightweight and also resistant to corrosion. Zinc can serve as a protective coating for other metals in the system, and may be also used in certain applications due to its conductivity and corrosion resistance.

The flexibility to use different materials allows for various design and environmental considerations, ensuring that the lightning protection system can be optimized for specific locations and conditions. This diversity in material choice is crucial to accommodate different installation needs and can enhance the overall effectiveness of the lightning protection system. Therefore, embracing all these materials for air terminals reflects both the practical and performance advantages they can offer in lightning protection applications.