Additionally, the duct and all field-applied joints shall maintain their structural integrity without developing any through openings. The fire exposure consisted of a square steel pan 1 ft x 1 ft x 8 in. At the start of the test the liquid surface was 12 in. The pan itself was positioned directly below the central axis of the duct. The following observations were noted during the fire test of the 12 in.
All distances are approximate.
Burning to approx. No Flaming or structural failure. The manufacturer shall make every reasonable effort to supply all necessary instructions and other assistance to the installer to ensure proper installation. Printed application instructions shall be provided by the manufacturer to demonstrate proper installation procedures. In some cases, a continued program of inspection shall be necessary to assess the application or changes within the application techniques.