Which of the following is not a good option for cable used in under carpet installations?

• A. Optical fiber cable
• B. Coaxial cable
• C. Armored cable
• D. Low-smoke zero-halogen cable

Answer: (B)

Under-carpet runs need cables that are thin, flexible, and unlikely to be damaged by foot traffic or furniture. Coaxial cable is relatively bulky and stiff, with a larger bend radius, so it doesn’t lay smoothly under carpet and is more prone to kinking, crushing, or snagging. That makes it a poor choice for under-carpet installations. In contrast, optical fiber is very small and flexible, and carries signals without electrical current, making routing under carpet safer and easier. Low-smoke zero-halogen cable adds fire-safety benefits in occupied spaces, and armored cable provides extra protection where needed, though it’s heavier and less flexible. The key reason coaxial isn’t favorable here is its bulk and rigidity, which aren’t well suited to a concealed, under-carpet route.