Flooring Radiant Panel
This test method is used to assess the critical radiant flux of flooring systems or cellulose insulation materials exposed to both a radiant heat source and a flame, within a test chamber, both in the USA (ASTM E 648, ASTM E 970, NFPA 253) and Europe (ISO/EN 9239), where the European Union made the test method one of the requirements for fire test approval of floorings. The test equipment is also similar to the one used to assess flammability of thermal/acoustic insulation materials in aircraft by the Federal Aviation Administration. Test Equipment dimensions are slightly different for ASTM E 648 and ISO 9239.
The radiant heat is applied by means of a propane gas-fueled panel, inclined at 30E, and directed at a horizontally mounted floor covering system specimen. The radiant panel generates a radiant energy flux distribution in the nominal range of 1.0 W/cm2 (at 150 mm) to 0.1 W/cm2 (at 900 mm).
In the critical radiant flux test, a pilot burner is used and the distance burned until flame-out is reached is converted, by calibration, into an equivalent critical radiant flux, in W/cm2. Traditionally, tests are conducted to give a maximum critical radiant heat flux of 1.1 W/cm2, but the tests can optionally be conducted with higher radiant heat input, to obtain critical radiant heat fluxes of up to 2.5 W/cm2.
In the FAA test, a different pilot burner is used: a small venturi torch with an axially symmetric burner tip and a propane supply tube (0.15 mm, 0.006 in. diameter, 71 mm, 2 7/8 in. long). An incident heat flux of 1.5 BTU/ft2/s (1.8 W/cm2) is then obtained at the FAA “zero” position of 51 mm (2 in.).
In the FAA test, the pilot burner flame is applied for 15 s (at a 27 E angle and at a distance of 12 mm, 0.5 in., above the sample) at the “zero” position. The test method assesses flame propagation away from the point of ignition, flame time, after-flame time, and shrinkage or melting of the specimen.
The normal radiant panel is a gas-fired panel (required for the ASTM, NFPA and ISO/EN tests), but for the FAA test an electrical panel can be supplied as an alternative.
- Optional measurements for the critical radiant flux test include smoke obscuration (requiring additional instrumentation in the exhaust duct, available from FTT), and flame spread rate. Data acquisition and control software is available for use with this instrument.