A cable type suitable for running in air ducts and spaces between the floor and ceiling, with a fire coating that must comply with building codes, is which of the following?

A cable type suitable for running in air ducts and spaces between the floor and ceiling, with a fire coating that must comply with building codes, is which of the following?

• A. riser cable
• B. NM cable
• C. Coaxial cable
• D. Armored cable

Answer: (A)

Cables that run through air ducts and the space between floors must have a fire-rated jacket to meet building codes, because those paths can spread flame quickly. Cables designed for vertical runs between stories—riser-rated cables—are specifically built for that purpose. They are tested and rated to limit fire spread in shafts and between floors, aligning with code requirements for fire resistance in these exact locations. That’s why riser-rated cable is the best choice. NM cable isn’t permitted in ducts or vertical shafts in many codes because its jacket can ignite and emit more smoke. Coaxial cable serves signal purposes and isn’t chosen for building-wide fire-rated installations in ducts. Armored cable offers physical protection, but without a proven fire-rating appropriate for ducts and risers, it doesn’t guarantee the required code compliance.

Cables that run through air ducts and the space between floors must have a fire-rated jacket to meet building codes, because those paths can spread flame quickly. Cables designed for vertical runs between stories—riser-rated cables—are specifically built for that purpose. They are tested and rated to limit fire spread in shafts and between floors, aligning with code requirements for fire resistance in these exact locations.

That’s why riser-rated cable is the best choice. NM cable isn’t permitted in ducts or vertical shafts in many codes because its jacket can ignite and emit more smoke. Coaxial cable serves signal purposes and isn’t chosen for building-wide fire-rated installations in ducts. Armored cable offers physical protection, but without a proven fire-rating appropriate for ducts and risers, it doesn’t guarantee the required code compliance.