Which wiring methods are permitted for shunt circuit conductors of auxiliary fire alarm systems?

Which wiring methods are permitted for shunt circuit conductors of auxiliary fire alarm systems?

• A. Rigid metal conduit only
• B. Electrical metallic tubing only
• C. Rigid metal conduit or electrical metallic tubing
• D. Any approved wiring method

Answer: (C)

Shunt circuit conductors in auxiliary fire alarm systems must be protected in a metal raceway to ensure reliable signaling and protection against damage in life-safety applications. Rigid metal conduit and electrical metallic tubing both provide the necessary mechanical protection, grounding/bonding paths, and resistance to environmental damage that these circuits require. They are recognized metal raceways suitable for critical fire alarm wiring. Other wiring methods, such as nonmetallic or flexible raceways, may not meet the required protection and listing for shunt conductors, so they aren’t permitted. Saying any approved wiring method is allowed would be too broad for this specialized circuit, since not all approved methods provide the same level of protection and reliability.

Shunt circuit conductors in auxiliary fire alarm systems must be protected in a metal raceway to ensure reliable signaling and protection against damage in life-safety applications. Rigid metal conduit and electrical metallic tubing both provide the necessary mechanical protection, grounding/bonding paths, and resistance to environmental damage that these circuits require. They are recognized metal raceways suitable for critical fire alarm wiring. Other wiring methods, such as nonmetallic or flexible raceways, may not meet the required protection and listing for shunt conductors, so they aren’t permitted. Saying any approved wiring method is allowed would be too broad for this specialized circuit, since not all approved methods provide the same level of protection and reliability.