In June 2012, UL learned of compatibility issues when Classified Fire-Resistive Cables were installed in systems where zinc was used as in interior coating in steel conduits, raceways and other system components. At the high temperatures the zinc coating vaporizes and interacts with the copper conductor creating a brass alloy. Brass melts at a lower temperature which compromises the integrity of the electrical system causing pre-mature failure.
April 6, 2022
UL2196: The Next Generation Fire Resistive Cables and Phenolic Conduit
In June 2012, UL learned of compatibility issues when Classified Fire-Resistive Cables were installed in systems where zinc was used as in interior coating in steel conduits, raceways and other system components. At the high temperatures the zinc coating vaporizes and interacts with the copper conductor creating a brass alloy. Brass melts at a lower temperature which compromises the integrity of the electrical system causing pre-mature failure.