When designing a fiber backbone using cable with an armored sheath, a major consideration that you must address is:

The type of metal (steel vs. aluminum) has minor implications but is not the primary design consideration; bonding and grounding apply regardless of which metal is used.

Sheath strength is a mechanical consideration for installation, not the major electrical safety concern that must be addressed in the backbone design.

Aluminum content is not a primary design variable; the grounding requirement applies to any conductive sheath material.

Rust is a long-term durability concern for outdoor steel sheaths but is secondary to the immediate safety and code requirement of bonding and grounding.

The metallic armor in an armored fiber cable creates a conductive path that, if left unbonded or ungrounded, can accumulate dangerous voltages from induced currents, lightning, or faults in nearby electrical systems. NEC Article 770 and related standards require that metallic cable sheaths be bonded to the grounding electrode system at each end to ensure safety and code compliance. Failure to address bonding and grounding is the most critical design consideration when specifying armored fiber for a backbone.