Except as required by Sections 602.2.1.1 through 602.2.1.5, materials within plenums shall be noncombustible or shall be listed and labeled as having a flame spread index of not more than 25 and a smoke-developed index of not more than 50 when tested in accordance with ASTM E 84 or UL 723.
4. This section shall not apply to smoke detectors.
5. Combustible materials fully enclosed within one of the following:
5.1. Continuous noncombustible raceways or enclosures.
5.2. Approved gypsum board assemblies.
6. Materials in Group H, Division 5 fabrication areas and the areas above and below the fabrication area that share a common air recirculation path with the fabrication area.
The foam plastic insulation shall exhibit a flame spread index of 25 or less and a smoke-developed index of 50 or less when tested in accordance with ASTM E 84 or UL 723 at the thickness and density intended for use and shall meet the acceptance criteria of Section 803.1.2 of the Florida Building Code, Building when tested in accordance with NFPA 286.
The foam plastic insulation shall be approved based on tests conducted in accordance with Section 2603.10 of the Florida Building Code, Building.