<a href="//commons.wikimedia.org/wiki/Bus_Duct" title="Bus Duct">Bus Duct</a> interior and exterior views. This Westinghouse bus duct section was used in a successful 2 hour <a href="//commons.wikimedia.org/wiki/Fire_test" title="Fire test">fire test</a> for a <a href="//commons.wikimedia.org/wiki/Firestop" title="Firestop">firestop</a> system. The interior firestop that was provided by the bus duct manufacturer was replaced with an 8" thickness of <a href="//commons.wikimedia.org/wiki/Mortar_(firestop)" title="Mortar (firestop)">firestop mortar</a> because of shrinkage of the material shown here and its insufficient thickness to enable a T rating of the assembly.
<a href="//commons.wikimedia.org/wiki/User:Achim_Hering" title="User:Achim Hering">Achim Hering</a>
2007-08-27
<span class="int-own-work" lang="en">Own work</span>